Field Geologists' Manual 4th Ed

FIELD GEOLOGISTS’ MANUAL MONOGRAPH SERIES ii COOPERATING ORGANISATIONS vii CONTENTS xi FOREWORD TO THE FIRST EDI...

Author: D.A. Berkman

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FIELD GEOLOGISTS’ MANUAL

MONOGRAPH SERIES

ii

COOPERATING ORGANISATIONS

vii

CONTENTS

xi

FOREWORD TO THE FIRST EDITION

v

FOREWORD TO THE FOURTH EDITION

v

PREFACE TO THE FIRST EDITION

ix

PREFACE TO THE FOURTH EDITION

x

1.

ETHICS AND REPORTING

1

2.

MINERAL AND ROCK INFORMATION

21

3.

GEOCHEMISTRY

61

4.

MINING AND ECONOMIC GEOLOGY

77

5.

GEOLOGICAL MAPPING

165

6.

GEOMETRIC AND SURVEYING DATA

271

7.

ENGINEERING GEOLOGY

289

8.

HYDROGEOLOGY

317

9.

GEOPHYSICS

337

10.

DRILLING

357

11.

MISCELLANEOUS

363

12.

MATHEMATICAL TABLES AND CONVERSION FACTORS

373

INDEX

391

MONOGRAPH SERIES 1.

• Detrital Heavy Minerals in Natural Accumulates

George Baker

1962

2.

• Research in Chemical and Extraction Metallurgy

Ed: J T Woodcock A E Jenkins and G M Willis

1967

3.

• Broken Hill Mines - 1968

Ed: M Kadmanovich and J T Woodcock

1968

4.

• Economic Geology of New Zealand

Ed: G J Williams

1974

5.

• Economic Geology of Australia and Papua New Guinea - 1. Metals

Ed: C L Knight

1975

6.

• Economic Geology of Australia and Papua New Guinea - 2. Coal

Ed: D M Traves and D King

1975

7.

• Economic Geology of Australia and Papua New Guinea - 3. Petroleum

Ed: R B Leslie H J Evans and C L Knight

1976

8.

• Economic Geology of Australia and Papua New Guinea - 4.

Ed: C L Knight

1976

Field Geologists’ Manual 1st Edition 2nd Edition 3rd Edition 4th Edition

Ed: D A Berkman and W Ryall Ed: D A Berkman Ed: D A Berkman Ed: D A Berkman

1976

• Mining and Metallurgical Practices in Australasia

Ed: J T Woodcock

1980

Ed: J T Woodcock

1984

• Australasian Coal Mining Practice 1st Edition 2nd Edition

Ed: C H Martin Ed: C H Martin and A J Hargraves

1986 1993

13.

• Mineral Deposits of New Zealand

Ed: Dr D Kear

1989

14.

Geology of the Mineral Deposits of Australia and Papua New Guinea

Ed: F E Hughes

1990

15.

The Rocks Speak

H King

1989

16.

• Hidden Gold - The Central Norseman Story

J D Campbell

1990

17.

• Geological Aspects of the Discovery of Some Important

K R Glasson and J H Rattigan

1990

Industrial Minerals and Rocks 9.

10.

1982 1989 2001

(the Sir Maurice Mawby Memorial Volume) 11.

• Victoria’s Brown Coal - A Huge Fortune in Chancery

(the Sir Willis Connolly Memorial Volume) 12.

Mineral Deposits in Australia 18.

• Down Under - Mineral Heritage in Australasia

Sir Arvi Parbo

1992

19.

Australasian Mining and Metallurgy (the Sir Maurice Mawby Memorial Volume, 2nd edition)

Ed: J T Woodcock and K Hamilton

1993

20.

Cost Estimation Handbook for the Australian Mining Industry

Ed: M Noakes and T Lanz

1993

21.

History of Coal Mining in Australia (the Con Martin Memorial Volume)

Ed: A J Hargraves, R J Kininmonth, C H Martin and S M C Saywell

1993

22.

Geology of Australian and Papua New Guinean Mineral Deposits

Ed: D A Berkman and D H Mackenzie

1998

Copies of all books currently in print can be obtained from The Institute office - Tel (03) 9662 3166 Key: • = Out of print

FIELD GEOLOGISTS’ MANUAL Compiled by D A BERKMAN

FOURTH EDITION — 2001

INCORPORATED BY ROYAL CHARTER 1955

Monograph No. 9

Published by THE AUSTRALASIAN INSTITUTE OF MINING AND METALLURGY Level 3, 15-31 Pelham Street, Carlton, Victoria, Australia 3005 2001 N

© Copyright by

THE AUSTRALASIAN INSTITUTE OF MINING AND METALLURGY

First Edition 1976 Reprinted 1978 Second Edition 1982 Reprinted 1987 Third Edition 1989 Revised and Reprinted 1995 Fourth Edition 2001

The Institute is not responsible, as a body, for the facts and opinions advanced in any of its publications

National Library of Australia Card No. ISBN 1 875776 850

Desktop published by Tatiana Feldman for The Australasian Institute of Mining and Metallurgy Printed in Australia by RossCo Print, Preston, Victoria, Australia 3072

Foreword to First Edition It is often stated that the strength of The Institute lies in its branches and this is so because within the branches most of the technical discussions and developments take place. During the minerals boom of the 1960s there was intense field geological activity with significant deposits of bauxite, coal, copper, petroleum, manganese, nickel, titanium, uranium, etc, being discovered and/or confirmed. Members of the Sydney Branch, one of the largest of The Institute branches, ranging through Australasia and beyond, were no less active in the exploration field than other Institute members during this time, and participated in these experiences and developments in techniques. Now, in the 1970s, as exploration proceeds at a slower pace, the vigorous Sydney Branch has recognised the need to consolidate these techniques into this comprehensive Field Geologists' Manual. It is of significance that the subject of the first pages of the manual, the Code of Ethics, was first drafted by the Sydney Branch for The Institute in the early 1960s. The Field Geologists' Manual is written and compiled particularly for Australasian use and provides a needed and valuable guide for the Australian field geologist. But in its wide coverage, in its broad references and in the widespread experience of Mr D A Berkman and his colleagues who assembled the material, the Manual should find wide use in field geology throughout the world. The work is a tribute to their expertise and to their desire to share this with their fellow geologists. C H MARTIN, President, June 1976

Foreword to the Fourth Edition Encouraged by his peers to make the wealth of data he had assembled for field work available to his fellow professionals, Don Berkman edited the Field Geologists’ Manual which was first published by The AusIMM in 1976. Achieving the status of a ‘reservoir of inexhaustible knowledge’, it was affectionately dubbed the ‘Junior Woodchuck Guidebook’ by a generation familiar with that Walt Disney icon. As knowledge continues to expand, so this fourth edition has been edited, upgraded and enlarged by a team of experts under the continuing leadership of Don Berkman. They continue The Institute’s proud tradition of advancing the interests of its professions by facilitating the exchange of information. May the Field Geologists’ Manual continue to be both a useful manual to all our members and an inspiration to new generations of professionals. R D ELVISH, President, September 2001

v

Cooperating Organisations Aberfoyle Limited Alcoa of Australia Limited Allied Eneabba Limited Amoco Minerals Australia Company Anaconda Australia Inc. Aquitaine Australia Minerals Pty. Ltd. The Australasian Institute of Mining and Metallurgy, Head Office The Australasian Institute of Mining and Metallurgy, New Zealand Branch The Australasian Institute of Mining and Metallurgy, Sydney Branch Australian Anglo American Limited Australian Oil & Gas Corporation Limited The Broken Hill Proprietary Company Limited Bureau de Recherches Geologiques et Minieres Bureau of Mineral Resources, Geology and Geophysics Carpentaria Exploration Company Pty. Ltd. Central Pacific Minerals N L Cliffs Western Australian Mining Co Pty. Ltd. Comalco Limited Consolidated Rutile Limited CRA Exploration Pty. Limited CSR Limited CSIRO Minerals Research Laboratories Department of Mines, South Australia Department of Mines, Tasmania Department of Natural Resources, Queensland The Electrolytic Refining and Smelting Company of Australia Limited Electrolytic Zinc Company of Australasia Limited Esso Australia Ltd. Geological Survey of New South Wales Geological Survey of Papua New Guinea Geological Survey of Queensland Geological Survey of Western Australia Geopeko Limited Goldsworthy Mining Limited Gold Producers Association Limited Greenbushes Tin Ltd. Hamersley Exploration Pty. Limited ICI Australia Limited International Nickel Australia Limited

James Cook University of North Queensland Jododex Australia Pty. Ltd. Joint Coal Board Kathleen Investments (Australia) Limited Kennecott Explorations (Australia) Ltd. Macquarie University Metals Exploration Limited Mineral Deposits Limited Minerals Mining and Metallurgy Limited Mines Administration Pty. Limited Mines Branch, Department of Northern Australia Mines Department, Victoria Mines Exploration Proprietary Limited Mobil Energy Minerals Australia Inc. Mount Isa Mines Limited Mount Newman Mining Co. Pty. Limited Nabalco Pty. Limited Newmont Holdings Pty. Ltd. New Zealand Geological Survey Noranda Australia Limited North Broken Hill Limited Occidental Minerals Corporation of Australia Pacminex Pty. Ltd. Peko-Wallsend Ltd. Placer Exploration Limited Poseidon Limited Project Mining Corporation Limited Renison Goldfields Consolidated Limited Savage River Mines Seltrust Holdings Limited Standards Australia International Limited Swiss Aluminium Mining Australia Pty. Ltd. Tennant Trading (Australia) Pty. Limited Umal Consolidated Limited Union Corporation (Australia) Pty. Ltd. Union Miniere Development and Mining Corporation Ltd. United States Steel International, Inc. The University of Adelaide The University of Melbourne The University of New England The University of New South Wales

vii

The University of Queensland The University of Sydney The University of Tasmania The University of Western Australia Utah Development Company Water Conservation and Irrigation Commission of NSW

Waipipi Iron Sands Limited Watts, Griffis and McOuat (Aust.) Pty. Ltd. Western Australian Institute of Technology Western Mining Corporation Limited Woodsreef Mines Limited

viii

Preface to the First Edition This manual is intended to provide, in one volume, a broad selection of basic material which may be required by a geologist during the course of his work. It is an attempt, with some personal bias, to abstract those critical parts of a reference library (to which all geologists require reasonable access) which may be of use during short term field projects. Obviously a geologist on a major and long term field investigation should have access to a number of textbooks to supplement the minimal data supplied here, and be provided with specific detailed material relating to the particular enquiry. Specialists may find that their individual area of knowledge has been only briefly covered, but as far as possible classifications which are widely accepted have been used—and these are often the simplest. This is not intended to be another textbook or recipe book, as in many cases the preliminary steps are not explained, and a standard of training or scholarship is assumed. The sources of individual sections (shown as footnotes), and several bibliographies, have been added for further reference. In some instances established or most suitable procedures are included where these are not readily available or not usually known. For topics in which employers or individuals have a standardised routine (e.g. the description of outcrops), only categories of information which should be recorded have been listed. The first draft of the manual was compiled over a period of five years, with considerable help in areas of specialised knowledge from the staff of the Bureau of Mineral Resources (for geological mapping, geophysics), the Geological Survey of New South Wales (for engineering geology, geohydrology) and Tennant Trading (Aust.) Pty. Ltd. (for commercial factors for common ores). With financial support from the Sydney Branch of The Institute, 65 copies of the first draft were produced, and circulated to the major Australian geological organisations in order to obtain an indication of the likely demand for the manual, and the type of information which should be included. The concept was generally favourably received, and a wide variety of alternative and additional information was contributed. Aid from those organisations which offered further material is acknowledged opposite as a list of cooperating organisations. The final draft, incorporating most of these suggestions, was composed with the advice of K R Glasson, M J Lawrence, and K G Mosher of the Sydney Branch Committee of The Institute. The volume was prepared for printing by W R Ryall, and edited by him with my assistance, based on advice readily provided by The Institute Honorary Editor, J T Woodcock. I am obliged to the Council and Sydney Branch Committee of The Institute, and to the CSIRO Minerals Research Laboratories, for the financial support which made possible the publication of the manual. I am particularly grateful to my employer, Australian Oil and Gas Corporation Limited, for encouragement and aid with this project from its inception. D A BERKMAN Compiler 1976

ix

Preface to the Fourth Edition The first edition of the Field Geologists’ Manual was prepared between 1971 and 1976. It was based on a collection of reference material the compiler used while supervising a group of multinational geologists for an emerging mineral exploration company. The collection was originally intended to be the nucleus of an in-house reference manual, but that proposal disappeared, like so many other projects, with the collapse of the ‘Poseidon’ nickel boom in 1972. The collection of reference material grew, with the active encouragement of Mr David McGarry and the Committee of the Sydney Branch of The Institute, into the 1st (1976) edition of this Manual. This edition was reprinted, as were the 2nd (1982) and 3rd (1990) editions. This 4th edition marks the 25th birthday of the Manual. It was prepared to maintain the Manual’s value as a comprehensive reference for field geoscience work. For this review the utility of each section of the Manual was assessed by Hugh Rutter and the staff of the Flagstaff GeoConsultants group. Many areas for revision were identified. However, many of the data, formulae and tables of the original (1976) Manual were retained after upgrading. This process of retaining basic information while adding new material is the cause of the growth of the Manual, from 295 pages in 1976 to about 400 pages in 2001. The revision was supported by Dr Neil Williams, the Director of the Australian Geological Survey Organisation (AGSO), who encouraged input from AGSO specialists, with their contributions channelled through Ms Louise Mitchell. Practically every stage in Section 2 ‘Minerals and Rock Information’ and Section 5 ‘Geological Mapping’ was reviewed by an AGSO officer, and revised where necessary. As part of this process the Geological Time Scale (Section 5.5) was updated under the direction of Dr G C Chaproniere, and the Abridged Guide to Stratigraphic Nomenclature in Australia (Section 5.7) was revised by Albert Brakel. A new section on Regolith Terminology was provided by Dr Graham Taylor of the CRC LME at the University of Canberra. Part 4.3 ‘Commercial Factors for Common Ores’ was completely revised, with assistance from Dr Ian Lambert and other AGSO geoscientists, and from consulting metallurgist Jim Woodcock. Flagstaff and other specialists added new information in this and earlier sections, on kimberlite and diamonds. Section 7 ‘Engineering Geology’ was updated by Robert L Smith, geotechnical engineer at the Perth office of Gutteridge Haskins and Davey Pty. Ltd., and Section 8 ‘Hydrogeology’ was modernised by Rob Ellis of the Queensland Department of Natural Resources. Flagstaff GeoConsultants revised the material in Section 9 ‘Geophysics’. Many other people have helped with this edition – far too many to thank individually on this page. Their assistance is much appreciated, and each individual’s assistance is acknowledged in a footnote to their contribution. The Institute’s Publications Committee suggested, early in the revision process, that information could be provided on computer applications and information technology in geoscience. This was not achieved, but the Manual has been provided in CD format. D A BERKMAN Compiler 2001

x

Contents v v ix x

FOREWORD TO THE FIRST EDITION FOREWORD TO THE FOURTH EDITION PREFACE TO THE FIRST EDITION PREFACE TO THE FOURTH EDITION

1. ETHICS AND REPORTING 1.1.1. 1.1.2. 1.2. 1.3. 1.4.1. 1.4.2. 1.5. 1.6.

Code of ethics Code for consultants Requirements for mining company reports to Australian stock exchanges Imperial and international paper sizes List of abbreviations Abbreviations used in petroleum exploration logs and scout reports Symbols for correcting proofs Selected bibliography on writing geological reports

1 4 6 8 9 13 17 19

2. MINERAL AND ROCK INFORMATION 2.1. 2.2.1. 2.2.2. 2.3.1. 2.3.2. 2.3.3. 2.3.4. 2.3.5. 2.4.1. 2.4.2. 2.5.1. 2.5.2. 2.5.3.

Mineral index List of common minerals in order of density Description of heavy liquids Classification of plutonic rocks - I.U.G.S. field system Classification of volcanic rocks - I.U.G.S. system Broad classification of igneous rocks by colour and grain size Classification of pyroclastic rocks - I.U.G.S. system Diamond indicator minerals Metamorphic facies diagram Summary of metamorphic rocks Classification of arenites and terrigenous sediments Classification of carbonate sediments Roundness and sphericity, relative resistance to abrasive rounding, and particle size terminology for sedimentary and pyroclastic particles 2.5.4. Bedding thickness terminology 2.5.5. A genetic classification of sedimentary structures 2.6. Diagrams representing various percentages of grains 2.7. Regolith terminology

21 37 40 42 43 43 44 45 48 49 51 52 53 55 55 56 57

3. GEOCHEMISTRY 3.1.1. 3.1.2. 3.1.3. 3.2. 3.3. 3.4. 3.5. 3.6. 3.7. 3.8.

Periodic table of the elements Alphabetical list of natural elements and common values Conversion factors, elements to compounds Average abundance of selected minor elements in the earth's crust Range of abundance of trace elements in soils Geochemical signature of mineral deposit types Approximate lower detection limits, in ppm, for the common geochemical analytical methods General notes for geochemical sampling Glossary of statistical terms and symbols Probability × 3 cycle log paper

xi

61 62 63 64 65 66 68 70 72 76

4. MINING AND ECONOMIC GEOLOGY 4.1.1. 4.1.2. 4.2. 4.3. 4.4.1. 4.4.2. 4.5.

Guidelines for environmental care in mineral exploration Guidelines for the preparation of an environmental impact statement Field chemical tests for common elements and mineral classes Commercial factors for common ores General preferred sample mass nomogram Graphs of particle size and preferred sample mass for gold assays Australasian code for reporting of Mineral Resources and Ore Reserves (the ‘JORC Code’) 4.6. Standard classification system for Australian hard coal 4.7.1. Summary of compound interest formulae 4.7.2. Table of compound interest factors 4.8. Ingredients, methods and stages in mineral exploration 4.9. Background data for a mine evaluation 4.10 Selected bibliography

77 80 83 90 122 123 125 140 142 144 162 163 164

5. GEOLOGICAL MAPPING 5.1. 5.2. 5.3.1. 5.3.2. 5.4.1. 5.4.2. 5.4.3. 5.4.4. 5.5. 5.6.1. 5.6.2. 5.6.3. 5.7. 5.8. 5.9. 5.10. 5.11. 5.12.

Index to Australian, New Zealand, and Papua New Guinea 1:250 000 scale maps showing magnetic declination Suppliers of geological and topographic maps and air photographs Lengths of degrees of the parallel and meridian, and conversion to the geocentric datum of Australia Conversion of the area of a one minute square to square kilometres and square miles Fractional scales and Imperial system equivalents Fractional scales and unit plan areas Nomogram for estimating area Nomogram for estimating true width Geological time scale Standard mapping symbols – AGSO system Graphic representation of coal seams Australian standard colour scheme and stratigraphic symbols for geological maps—Facing page Abridged guide to lithostratigraphic nomenclature in Australia Check lists for recording outcrop information Classification of faults Classification of folds by dip isogons and by hinge surface Graph showing angle of true dip or slope, vertical exaggeration, and exaggerated dip Selected bibliography

165 169 171 173 175 176 178 179 180 192 253 254 255 265 266 267 269 269

6. GEOMETRIC AND SURVEYING DATA 6.1. 6.2.1. 6.2.2. 6.3. 6.4. 6.5. 6.6.1. 6.6.2. 6.7.

Formulae for solution of triangles Formulae for area, perimeter, etc of planar figures Formulae for surface area, volume etc of solids Apparent dip in a direction not perpendicular to the strike Table of slope angles, gradients, and per cent grade Field grid spacing and elevation conversion table Stadia formula and method of checking a theodolite Stadia tables Airphoto scale nomogram and formula

xii

271 272 274 276 277 278 280 281 282

6.8. 6.9. 6.10.

Determination of the line of intersection of two planes (tangent vector method) Graphical solution of the three point problem Orthographic and Wulff (equal angle) stereonets, Schmidt (equal area) stereonet and contouring device

283 283 284

7. ENGINEERING GEOLOGY 7.1.1. 7.1.2. 7.2.1. 7.2.2. 7.3.1. 7.3.2. 7.3.3. 7.3.4. 7.3.5. 7.3.6 7.4.1. 7.4.2. 7.5.1. 7.5.2. 7.5.3. 7.5.4. 7.5.5. 7.6. 7.7.1. 7.7.2.

Field geotechnical testing methods Laboratory geotechnical testing methods Physical properties for unweathered rocks Static mechanical properties of unweathered rocks Recommended order of description of rock properties Rock weathering classification Rock strength classes Bulking factors for expansion of common rock materials Discontinuity spacing Aperture of discontinuity surfaces Common defects in rock mass Classification of landslides Order of description of soils Description, identification and classification of soils Calcareous sedimentary rock nomenclature Consistency of soils Soil moisture content Dynamic penetration test Hydraulic conductivity (permeability) Summary of arithmetic mean of hydraulic properties for all rock types

289 290 291 293 294 294 294 295 296 296 297 300 305 306 308 309 309 310 313 314

8. HYDROGEOLOGY 8.1.1. 8.1.2. 8.2.1. 8.2.2. 8.2.3. 8.2.4. 8.2.5. 8.2.6. 8.2.7. 8.2.8. 8.2.9. 8.2.10. 8.3.1. 8.3.2. 8.3.3. 8.3.4.

The International Association of Hydrogeologists Australasian hydrogeology authorities Approximate water supply requirements for homes and farms Windmill pumping capacity Volumes corresponding to standard pipe sizes Graph showing flow from various diameter pipes Factors for calculating volume of partially filled horizontal circular tanks Conversion factors for units of pressure Conversion factors for pumping test units Circular orifice meter discharge table Rectangular and V-notch weir board discharge table Pressure corresponding to head of water Notes on water sampling Guidelines for characteristics of drinking water Recommended stock water quality Recommended irrigation water quality

317 317 319 320 321 322 323 323 324 326 327 328 328 331 332 334

9. GEOPHYSICS 9.1. 9.2. 9.3. 9.4.

Physical properties and conversion factors Gravity surveying methods and tables Magnetic survey methods and tables Electromagnetic, resistivity and induced polarisation survey methods and tables

xiii

337 338 341 342

9.5. 9.6. 9.7. 9.8. 9.9.

Radiometric surveys and tables Seismic survey methods and data Down-hole survey methods Airborne survey methods Earthquake magnitude and intensity

349 352 353 353 354

10. DRILLING 10.1. 10.2.1. 10.2.2. 10.3. 10.4.

Nominal core and hole diameters, and volumes per foot and per metre length Calculation of drillhole elevations and coordinates from down-hole surveys Estimation of hole dip from acid tube surveys Determination of true width from oblique drillhole intersection Check lists for drillhole logging

357 359 360 361 362

11. MISCELLANEOUS 11.1. 11.2. 11.3. 11.4.1. 11.4.2. 11.5.1. 11.5.2. 11.6.

Addresses of Australasian Geological Surveys and Universities with geoscience departments Safety precautions on entering old workings Radio alphabet Time of beginning and end of daylight for the southern hemisphere Seventy year letter calendar Graph paper, millimetre ruling Triangular graph paper Occupational health and safety

363 364 366 367 368 370 371 372

12. MATHEMATICAL TABLES AND CONVERSION FACTORS 12.1. 12.2. 12.3.1. 12.3.2. 12.3.3. 12.4.

Trigonometric functions The International System of units (SI) Recommended practice for metric conversion Conversion factors, Imperial and International systems Conversion factors for foreign, rare and obsolete weights and measures Comparison table of USA, Tyler, Canadian, British, French and German standard sieve series

INDEX

373 375 376 384 388 389 391

xiv

1. ETHICS AND REPORTING 1.1.1. CODE OF ETHICS1

PREAMBLE The Australasian Institute of Mining and Metallurgy (The Institute), founded in 1893 and incorporated by Royal Charter in 1955, includes under its Charter and Bye-Laws an assemblage of scientists, engineers and technologists who are concerned in various ways with the discovery, extraction and utilisation of minerals, metals and energy sources. The membership includes geologists and other geoscientists, mining engineers and metallurgists, other engineers and other scientists and technologists; also other professional and paraprofessional groups who are engaged in or associated with the industries; also students who are preparing for careers in the industries. The grades of membership include Fellows, Members and Company Members, who are Corporate Members, and Affiliates, Graduates and Students (NB: Affiliate grade eliminated in 1994). All members of The Institute are required under Bye-Law 30 to comply with the Code of Ethics and with the Code for Consultants when practising as such.

industries, and with the rules, regulations and practices as established and promulgated by the Australian or New Zealand stock exchanges with respect to the official listing requirements for mining and/or other companies.

INTERPRETATIONS CLAUSE 1:

The responsibility of members for the welfare, health and safety of the community shall at all times come before their responsibility to the profession, to sectional or private interests, or to other members. The principle here is that the interests of the community have priority over the interests of others. It follows that a member: a.

CODE OF ETHICS 1.

The responsibility of members for the welfare, health and safety of the community shall at all times come before their responsibility to the profession, to sectional or private interests, or to other members.

2.

Members shall act so as to uphold and enhance the honor, integrity and dignity of the profession.

3.

Members shall perform work only in their areas of competence.

4.

Members shall build their professional reputation on merit and shall not compete unfairly.

5.

Members shall apply their skill and knowledge in the interests of their employer or client for whom they shall act, in professional matters, as faithful agents or trustees.

6.

Members shall give evidence, express opinions or make statements in an objective and truthful manner and on the basis of adequate knowledge.

7.

Members shall continue their professional development throughout their careers and shall actively assist and encourage those under their direction to advance their knowledge and experience.

8.

Members shall comply with all laws and government regulations relating to the mineral

1.

From The AusIMM, 2001. http://www.ausimm.com/codes/ethics/ethics.asp

Field Geologists’ Manual

b.

c. d.

e.

shall avoid assignments that may create a conflict between the interests of his client or employer and the public interest; shall work in conformity with acceptable technological standards and not in such a manner as to jeopardise the public welfare, health or safety; shall endeavour at all times to maintain technological services essential to public welfare; shall in the course of his professional life endeavour to promote the well-being of the community. If his judgement is over-ruled in this matter he should inform his client or employer of the possible consequences (and, if appropriate, notify the proper authority of the situation); shall, if they consider that by so doing they can constructively advance the well-being of the community, contribute to public discussion on scientific and technological matters in their area of competence.

CLAUSE 2:

Members shall act so as to uphold and enhance the honor, integrity and dignity of the profession. The principle here is that the profession should endeavour by its behaviour to merit the highest esteem of the community. It follows that a member: a.

shall not involve himself with any business or professional practice which he knows to be of fraudulent or dishonest nature;

1

ETHICS AND REPORTING

b.

c.

shall not use association with other persons, corporations or partnerships to conceal unethical acts; shall not continue in partnership with, nor act in professional matters with any person who has been removed from membership of The Institute because of unprofessional conduct.

this respect it is immaterial whether or not the member is aware that others may have been requested to submit proposals, including fee proposals, for the same work; d.

shall promote the principle of engagement upon the basis of merit. He shall uphold the principle of adequate and appropriate remuneration for professional staff and shall give due consideration to terms of employment which have the approval of the profession’s appropriate association;

e.

shall not attempt to supplant another, employed or consulting, who has been appointed;

f.

in the practice of consulting, shall not undertake professional work on a basis which involves a speculative fee or remuneration which is conditional on implementation of the work. This does not preclude competitions conducted within Australia or New Zealand provided that such competitions are conducted in accordance with conditions approved by The Institute;

g.

shall neither falsify nor misrepresent his or his associate’s qualifications, experience and prior responsibility;

h.

shall neither maliciously nor carelessly do anything to injure, directly or indirectly, the reputation, prospects or business of others;

i.

shall not use the advantages of a privileged position to compete unfairly with others;

j.

shall exercise due restraint in explaining his own work and shall refrain from unfair criticism of the work of another;

k.

shall give proper credit for professional work to those to whom credit is due and acknowledge the contribution of subordinates and others;

l.

may properly use circumspect advertising (which includes direct approaches to prospective clients by any means) to announce his practice and availability. The medium or other form of communication used and the content of the announcement shall be dignified, becoming to a professional person and free from any matter that could bring disrepute on the profession. Information given must be truthful, factual and free from ostentatious or laudatory expressions or implications.

CLAUSE 3:

Members shall perform work only in their areas of competence. To this end The Institute has determined that: a.

a member shall inform his employer or client, and make appropriate recommendations on obtaining further advice, if an assignment requires qualifications and experience outside his field of competence; and

b.

in the practice of consulting a member shall not describe himself, nor permit himself to be described, nor act as a consultant unless he is a Corporate Member, occupies a position of professional independence, is prepared to design and supervise works or act as an unbiased and independent adviser, and conduct his practice in strict compliance with the conditions approved by the Council of The Institute.

CLAUSE 4:

Members shall build their professional reputation on merit and shall not compete unfairly. The principle here is that members shall not act improperly in a professional sense to gain a benefit. It follows that a member: a.

shall only approach prospective clients or employers with due regard to his professional independence and to this Code of Ethics;

b.

shall neither pay nor offer directly or indirectly inducements to secure work;

c.

shall promote the principle of selection of consultants by clients upon the basis of merit, and shall not compete with other consultants on the basis of fees alone. It shall not be a breach of the Code of Ethics for a member, upon an inquiry made in that behalf by a client or prospective client, to provide information as to the basis upon which he usually charges fees for particular types of work. Also it shall not be a breach of the Code of Ethics for a member to submit a proposal for the carrying out of work which proposal includes, in addition to a technical proposal and an indication of the resources which the member can provide, information as to the basis upon which fees will be charged or as to the amount of the fees for the work which is proposed to be done. In

2

CLAUSE 5:

Members shall apply their skill and knowledge in the interests of their employer or client for whom they shall act, in professional matters, as faithful agents or trustees. It follows that a member: a.

shall at all times avoid all known or potential

Field Geologists’ Manual

ETHICS AND REPORTING

conflicts of interest. He should keep his employer or client fully informed on all matters, including financial interests, which could lead to such a conflict. In no circumstances should he participate in any decision which could involve him in conflict of interest; b.

shall, when acting as administrator of a contract, be impartial as between the parties in the interpretation of the contract. This requirement of impartiality shall not diminish his duty to apply his skill and knowledge in the interests of the employer or client;

c.

shall not accept compensation, financial or otherwise, from more than one party for services on the same project, unless the circumstances are fully disclosed to, and agreed to by all interested parties;

d.

shall neither solicit nor accept financial or other valuable considerations, including free designs, from material or equipment suppliers for specifying their products;

e.

shall neither solicit nor accept gratuities, directly or indirectly, from contractors, their agents, or other parties dealing with his client or employer in connection with work for which he is responsible;

f.

shall advise his client or employer when as a result of his studies he believes that a project will not be viable;

g.

shall neither disclose nor use confidential information gained in the course of his employment without express permission.

taken to affect his judgement in a technical matter about which he is making a statement or giving evidence. CLAUSE 7: Members shall continue their professional development throughout their careers and shall actively assist and encourage those under their direction to advance their knowledge and experience. The principle here is that members shall strive to widen their knowledge and improve their skill in order to achieve a continuing improvement of the profession. It follows therefore that a member: a.

shall encourage his professional employees and subordinates to further their education, and

b.

shall take a positive interest in, and encourage his fellows actively to support The Institute and other professional organisations which further the general interests of the profession.

CLAUSE 8:

Members shall comply with all laws and government regulations relating to the mineral industries, and with the rules, regulations and practices as established and promulgated by the Australian or New Zealand stock exchanges with respect to the official listing requirements for mining and/or other companies. It follows that a member: a.

shall inform himself of the laws and regulations relating to the mineral industries in Australia and the States and Territories, and in New Zealand and other countries where he may be engaged as an employee or consultant;

b.

shall observe the requirements of stock exchanges in respect to reports on mineral exploration and assessment issued by listed companies. In the particular case of the Australian Associated Stock Exchanges he shall meet the requirement of a ‘competent person’ in that he shall be a Corporate Member of The Institute and shall have a minimum of five years’ experience in the field of activity on which he is reporting.

CLAUSE 6:

Members shall give evidence, express opinions or make statements in an objective and truthful manner and on the basis of adequate knowledge. It follows that: a.

a member’s professional reports, statements or testimony before any tribunal shall be objective and accurate. He shall express an opinion only on the basis of adequate knowledge and technical competence in the area, but this shall not preclude a considered speculation based intuitively on experience and wide relevant knowledge;

b.

a member shall reveal the existence of any interest, pecuniary or otherwise, that could be

Field Geologists’ Manual

3

ETHICS AND REPORTING

1.1.2. CODE FOR CONSULTANTS PREAMBLE The Australasian Institute of Mining and Metallurgy, founded in 1893 and incorporated by Royal Charter in 1955, includes under its Charter and Bye-laws an assemblage of scientists, geoscientists, engineers, technologists and other professional non-technical and para-professional groups who are concerned in various ways with the discovery, extraction and utilisation of minerals, metals and energy sources; also students who are preparing for careers in the Minerals Industry. All members of The Institute are required under Bye-laws of The Institute to comply with the Code of Ethics and with the Code for Consultants when practising as such.

they shall act as agent and trustee. However, in the interpretation of contract documents, the consultant shall maintain an attitude of scrupulous impartiality as between client and contractor and shall, as far as possible, ensure that each party to the contract shall discharge the duties and enjoy the rights set down in the contract agreement. FAVOURS

1.04

CODE FOR CONSULTANTS ETHICS

1.01

The professional attitude of consultants to their work and the client is regulated by the Charter, Bye-laws, and Code of Ethics of The Institute.

DEFINITION OF CONSULTANT

1.02

1.05

1.

4

A consultant acts for and is remunerated solely by the client, with whom the relationship is that of a professional adviser and not that of an employee. In the preparation of reports, plans, specifications, and contract documents, and in the supervision of construction work, consultants shall assiduously watch and conserve the interests of the client, for whom

From The Australasian Institute of Mining and Metallurgy Bye-laws, 1995. The AusIMM Bulletin, 6:9-10.

Should the consultant be entitled to receive either directly or indirectly any royalty, commission, or the like on any patented, protected or copyright article or process used in connection with work which is being carried out for a client, the consultant shall, prior to the use of such article or process, inform the client in writing of such entitlement.

BUSINESS INTERESTS

1.06

A consultant, when practising in that capacity, shall not deal on behalf of a client with any company, firm or business of which the consultant is a director or member or in which the consultant has any significant financial interest, without first disclosing the details of the fact in writing to the client.

1.07

Consultants may properly use circumspect advertising (which includes direct approaches to prospective clients by any means) to announce their practice and availability. The medium or other form of communication used and the content of the announcement shall be dignified, becoming to a professional person and free from any matter that could bring disrepute on the profession. Information given must be truthful, factual and free from ostentatious or laudatory expressions or implications.

RELATION TO CLIENT

1.03

The consultant shall not accept any commission, substantial service, or favour from any person who has offered or contracted to supply any material, equipment or services for, or who has engaged to execute any work in connection with, any works or undertakings designed or supervised by the consultant.

ROYALTIES

A consultant is a person who possesses the necessary qualifications and professional independence to advise on matters within a specific professional field. For the purpose of providing consulting services, the consultant shall, as necessary, maintain an office and employ staff. In all professional matters, consultants shall maintain a strictly fiduciary relationship to any client whom they may advise, and while so doing, shall not, without so informing his client, be directly or indirectly connected with any undertaking in any manner which may influence their professional judgement, or the interest of the client. Consultants shall not engage in any conduct, nor act in any capacity, nor hold any appointment, which prejudices their position as a consultant as defined above.

1

CONTINUANCE OF PARTNERSHIP

1.08

No member shall continue in partnership with, nor act in association or conjunction with, any member who has been removed from membership of The Institute under the terms and conditions expressed in the Bye-laws.

Field Geologists’ Manual

ETHICS AND REPORTING

CONSULTANTS GENERALLY

c.

Consultants shall not knowingly accept professional work in connection with which another member has been appointed to act, except in collaboration with such other member, unless he be formally notified by the client that they are required to act, and that the other member has been appropriately notified, and

A consultant having any interest or bias in the subject matter or of any matter referred to in a report prepared by the consultant, shall make a clear and complete disclosure of such interests and bias in the report.

d.

Consultants shall not conduct themselves in a manner or act in any capacity nor hold any appointment which, in the opinion of the Council, prejudices their status as a consultant or the interests of The Institute.

A consultant who is an employee should draw the employer’s attention to these rulings in relation to any report for publication that they may be called upon to compose or sign. In any case of difficulty, the consultant concerned should notify The Institute.

e.

If a report is translated, consultants should ensure that the translation accurately expresses the original meaning of Government and stock exchange regulations.

1.09 a.

b.

c.

Members who are directors or responsible officers of companies carrying on a practice as consultants should endeavour to ensure at all times that the professional practice of the company conforms to the spirit of The Institute’s Charter, Bye-laws and Code of Ethics.

GOVERNMENT AND STOCK EXCHANGE REGULATIONS

1.11

Consultants shall comply with the laws and regulations relating to the mineral industries in Australia and in the States and Territories, and in New Zealand and other countries where they may be engaged.

1.12

Consultants shall comply with the requirements of stock exchanges in respect to reports on mineral exploration and assessment issued by listed companies. In the particular case of the Australian Associated Stock Exchanges the consultant shall meet the requirement of a ‘competent person’ in that they shall be Corporate Members of The Institute and shall have a minimum of the five years’ experience in the field of activity on which they are reporting.

REPORTS FOR PUBLICATION IN CONNECTION WITH COMMERCIAL UNDERTAKINGS

1.10 a.

All consultants shall do their utmost to ensure that their reports, whenever published, whether in full or in summarised form, are signed and dated prior to publication, provided that, in the case of a partnership, they may use the firm’s signature.

b.

No consultant shall submit a report on a mining property or a metallurgical process for the purpose of appraisal without stating explicitly the evidence upon which the report is made and to what extent the report is founded on their personal observations or those of their trusted assistants. In any case of a mining property no consultant shall attach their signature to such an appraisal report without having inspected the property unless there are compelling reasons to the contrary which must be stated and justified in the report.

Field Geologists’ Manual

INTERPRETATION

1.13

Where in this Code the singular occurs it shall be understood to include the plural, and where the plural occurs, it shall be understood to include the singular, without in either case altering the meaning of the context.

5

ETHICS AND REPORTING

1.2. REQUIREMENTS FOR MINING COMPANY REPORTS TO 1 AUSTRALIAN STOCK EXCHANGES EXPLANATORY NOTE This chapter sets out some of the disclosure requirements that mining entities and others must satisfy. A mining entity includes a mining producing entity and a mining exploration entity. Where indicated, other entities must comply with requirements in this chapter. Usually the disclosure is required from an entity which has, or whose child entity has, acquired an interest in a mining tenement. Information for release to the market must be given to ASX’s company announcements office.

WHEN TO REPORT MINING PRODUCING ENTITIES AND OTHERS

1.2.1 A mining producing entity, and any other entity that ASX asks, must complete a report (consolidated if applicable) concerning each quarter of its financial year and give it to ASX. It must do so no later than 1 month after the end of the quarter. The report must include each of the following. (i)

Details of the mining production and development activities of the entity or group relating to mining and related operations, and a summary of the expenditure incurred on those activities. If there has been no production or development activity, that fact must be stated.

(ii) A summary of the exploration activities (including geophysical surveys) of the entity or group, and a summary of the expenditure incurred on those activities. If there has been no exploration activity, that fact must be stated. MINING EXPLORATION ENTITIES AND OTHERS

1.2.2 A mining exploration entity, and an entity which has or whose child entity has acquired an interest in a mining tenement, must complete a report (consolidated if applicable) concerning each quarter of its financial year and give it to ASX. It must do so no later than 1 month after the end of the quarter. The report must include each of the following. (i)

1.

6

Details of the exploration activities of the entity or group (including geophysical

From Australian Stock Exchange Listing Rules, September, 1999, Chapter 5 (Additional reporting on mining and exploration activities).

surveys), and a summary of the expenditure incurred on those activities. If there has been no exploration activity, that fact must be stated. (ii) Details of the mining production and development activities of the entity or group relating to mining, mining exploration and related operations, and a summary of the expenditure incurred on those activities. If there has been no production or development activity, that fact must be stated. (iii) If ASX asks, the mining exploration entity, or entity which has or whose subsidiary has acquired an interest in a mining tenement, must include each of the following items in each quarterly report. (a) The location of mining tenements held. (b) The location of mining tenements disposed of during the quarter. (c) Beneficial percentage interests in farm-in or farm-out agreements acquired or disposed of during the quarter. MINING EXPLORATION ENTITY TO COMPLETE APPENDIX 5B (QUARTERLY REPORT)

1.2.3 A mining exploration entity must also complete Appendix 5B and give it to ASX. It must do so immediately the information is available, and in any event within 1 month after the end of each quarter of its financial year.

REQUIREMENTS FOR REPORTS REPORTS TO COMPLY WITH APPENDIX 5A (THE JORC CODE)

1.2.4 A report prepared by a mining entity, or an entity which has or whose child entity has an interest in a mining tenement, must be prepared in accordance with Appendix 5A if the report includes a statement relating to any of the following. (a) Exploration results. (b) Mineral resources or ore reserves. (i) However, an entity need not comply with Appendix 5A to the extent that if rule 1.2.8 allows a report to be based on information compiled by a recognised mining professional, the

Field Geologists’ Manual

ETHICS AND REPORTING

report need not be prepared by or under the direction of and signed by a competent person. The requirements of Appendix 5A applying to a competent person apply to the recognised mining professional1. CONTENT OF REPORTS

1.2.5 During the exploration stage, a report in the field of minera1 exploration must include the following information. (1) The type and method of sampling. (2) The distribution, dimensions, assay results and relative location of all relevant samples.

(4) The flow rate. (5) The choke size used during testing. (6) Any other relevant basic data. COMPETENT PERSON OR RECOGNISED MINING PROFESSIONAL TO COMPILE INFORMATION ABOUT MINERALS

1.2.8 A report relating to an entity’s mineral resources or ore reserves, must be based on information compiled by a competent person. However, if the resource or reserve is not located in Australia, the report may be based on information compiled by a recognised mining professional. (i)

(3) Any other relevant basic data. (i) If true dimensions (particularly width of mineralisation) are not stated in the report, an appropriate qualification must be included. 1.2.6 Assay results must be reported using one of the following methods. The method used must be the most suitable according to the entity’s geologist or mining engineer and must be stated. Method 1 All assay results, with sample widths or size in the case of bulk samples. Method 2 The weighted average grade of the mineralised zone, indicating clearly how the grade was calculated. When high values are recorded, they must be given in context, with full supporting data. 1.2.7 During the prehydrocarbon reserve stage, a report, statement or assessment on hydrocarbon exploration must include the following information. (1) The depth of the zone tested. (2) The age and, if appropriate, the rock type and formation name of the zone tested. (3) Any liquids recovered.

(ii) If the report is based on information compiled by a recognised mining professional, it must include each of the following statements. (a)

A statement by the recognised mining professional that the report complies with Appendix 5A (except paragraph 9).

(b)

A statement by the entity that the person is a recognised mining professional and the basis on which each of the requirements for a recognised mining professional are met.

PERSON COMPILING INFORMATION ABOUT HYDROCARBONS

1.2.9 A report relating to an entity’s hydrocarbon reserves must be based on information compiled by a person who has a degree (or equivalent) in geology, geophysics, petroleum engineering or a related discipline; is practising or teaching geology, geophysics or petroleum engineering; and has practised or taught one of them for at least 5 years. (i)

1.

A recognised mining professional is a person who has each of the following:

The report must either state that it is based on the information, or be accompanied by a statement to that effect signed in the same manner as the report.

The report must either state that it is based on the information, or be accompanied by a statement to that effect signed in the same manner as the report.

(1) A degree or an overseas equivalent in geology, mining engineering or a related discipline relevant to the estimation of the type of mineral resource or ore reserve referred to in the report.

PERSON COMPILING INFORMATION TO BE IDENTIFIED

(2) At least five years experience in the estimation, assessment and evaluation of the type of mineral resource or ore reserve referred to in the report.

1.2.10 If the person referred to in rules 1.2.8 and 1.2.9 who compiles the information is a full time employee of the entity, the report or attached statement must say so and name the person.

(3) Membership of a recognised overseas professional body that has agreed to sanction the person if the person does not comply with Appendix 5A.

1.2.11 The person referred to in rules 1.2.8 and 1.2.9 who compiles the information must consent in

Field Geologists’ Manual

7

ETHICS AND REPORTING

writing to the inclusion in the report of the matters based on the information in the form and context in which it appears. The report or attached statement must state that the person consents, contain the name of the person and, if the person is not a full time employee of the entity, the name of the person’s firm or company.

1.2.14 A report relating to the pre-hydrocarbon reserve stage must not use the word ‘reserves’ in isolation. 1.2.15 A report relating to the results of exploratory investigations which have reached the stage where a hydrocarbon reserve can be estimated must use the expressions for categories of hydrocarbon reserves in the listing rules.

PROGRESS REPORT ON GEOPHYSICAL SURVEY

1.2.12 A report on the progress of any geophysical survey must include the name, nature and status of the survey, and the permit under which the survey is being conducted. HYDROCARBON REPORTS

1.2.13 Probable hydrocarbon reserves must only be reported in conjunction with proved hydrocarbon reserves. Possible hydrocarbon reserves must only be reported in conjunction with proved hydrocarbon reserves and probable hydrocarbon reserves.

TERMS OF A MINING TENEMENT JOINT VENTURE

1.2.16 An entity must not enter a joint venture agreement to investigate or explore a mining tenement, unless the agreement provides that if the entity requires it the operator will give the entity all the information the entity requires to comply with the Listing Rules; and that the information may be given to ASX for release to the market if necessary for the entity to comply with the listing rules.

1.3. IMPERIAL AND INTERNATIONAL PAPER SIZES Most Australasian countries now use the standard paper sizes recommended by the International Organization for Standardization (ISO), which are described in Australian Standard 1612. Some Imperial sizes, used in historic documents, are also shown below. There are three ISO size series, A, B and C, in which the ratio of one side to the other is 1: 2, i.e. 1:1.414 after trimming. The A series is based on the A0 size of

1189 by 841 millimetres of area one square metre, the basis of the B series is B0, of 1414 by 1000 millimetres, and the basic C size is C0, of 1297 by 917 millimetres. Each of the sizes in a series is exactly half the area of the next highest member, ie A4 is exactly half the area of A3, and is produced by a single fold. A0 is the largest sheet that will fit in a flat or ‘Vertiplan’ plan filing cabinet without folding.

Imperial paper and plan sizes

Imperial paper and plan sizes

Size

Size

inches

mm

Crown octavo

718 × 434

181 × 121

Demy octavo

834 × 538

222 × 137

Imperial

Foolscap quarto

818 × 612

206 × 165

Double Demy

241 × 152

Double Elephant

Royal octavo

91

2

×6

Princess

inches

mm

28 × 21 1 2

711 × 546

30 × 22

762 × 559

35 × 22 1 2

889 × 572

40 × 27

1016 × 686

Crown quarto

912 × 714

241 × 184

Quad Crown

40 × 30

1016 × 762

Demy quarto

10 3 4 × 8 1 2

273 × 216

Double Princess

44 × 28

1118 × 711

Foolscap folio

13 1 8 × 8 1 4

333 × 210

Quad Demy

44 × 32 1 2

1118 × 826

Brief

13 1 8 × 18 1 2

333 × 470

Antiquarian

53 × 21

1346 × 533

Demy

23 × 18 1 2

584 × 470

Eight Crown

57 1 2 × 41 3 4

1461× 1060

8

Field Geologists’ Manual

ETHICS AND REPORTING

International paper sizes, A series A series A0

mm

inches

841 × 1189

46.81 × 33.11

International paper sizes, C series C series

mm 1297 × 917

C0

A1

594 × 841

33.11 × 23.39

C1

917 × 648

A2

420 × 594

23.39 × 16.54

C2

648 × 458

A3

297 × 420

16.54 × 11.69

C3

458 × 324

A4

210 × 297

8.27 × 11.69

C4

324 × 229

International paper sizes, B series

C5

229 × 162

C6

162 × 114

mm

inches

C7

114 × 81

B0

1000 × 1414

39.37 × 55.67

C8

81 × 57

B1

707 × 1000

27.83 × 39.37

B2

500 × 707

19.68 × 27.83

B series

B3

353 × 500

13.90 × 19.68

B4

250 × 353

9.84 × 13.90

B5

176 × 250

6.93 × 9.84

If a plan is needed intermediate between the A series listed above, one of the B or C sizes may be used.

1.4.1. LIST OF ABBREVIATIONS about

c or ca.

absolute

andalusite

andal.

Australian

abs.

andesite

ad.

abundant

A.

angular

ang.

actinolite

act.

angstrom

agglomerate

aggl.

anhydrous

aggregate

aggr.

ante meridiem

a.m.

average

aph.

azurite

ap.

band (s)

bd(s)

banded

bnd.

alkaline

alk.

aphyric

altered

alt.

aplite

alternating

approximately

current

a.c.

amorphous

amor.

ampere

A

April aqueous

and

amyg. not abbreviated

Australian Standard

AS

ampere hour

Ah

Field Geologists’ Manual

az.

banded iron formation (s)

BIF (s) ba. bas.

atomic

(aloidal)

av.

basalt

at.wt

amygdule

aq.

ASS

atm.

atomic weight

Aug.

Apr.

Specification

barite

atmospheric (ic)

amphib.

approx.

Standard

ark.

at.%

amphibole (ite)

anhyd

AS

Australian

arkose (ic)

atomic per cent August

A

Standard

at.

atomic absorption spectrometer

bauxite bedded

AAS

bentonite

bx. bdd bent.

atomic per cent

at.%

biotite

bio.

atomic weight

at.wt

bituminous

bit.

August

Aug.

black

blk

arenaceous

aren.

argillaceous

argill.

blue

bl.

boiling point

b.p.

borax

bo.

9

ETHICS AND REPORTING

bornite

bn.

common

com.

bottom

bot.

compact

cpt

degree (angle)

bldr (s)

compare

cf.

degree absolute

boulder (s) breccia brecciated

brec. brectd

Brinnell hardness number British Standard

BHN BS

British Standard

composition concentrate (s)

conct. (s)

db ° °K

(Kelvin) degree (Celsius)

conc.

concentration

concn.

density

conchoidal

conch.

diameter

dia.

concretion

conc.

dilute

dil.

BSS

conglomerate

broken

bkn

consolidated

brown

br.

constant

cgl. consol. const.

contaminant

dense

°C

concentrated

Specification

calcareous,

comp.

decibel

d. D

dimorphous

dimorph.

diopside

diop.

direct current

d.c.

distilled

dist.

calcite

calc.

(ated)

contm.

distributed

dist.

calculated

calc.

contorted

conttd

distribution

distn

cal

corrected

corr.

cal.val.

cosecant

cosec

calorie calorific value candela carbonaceous

cd carb.

dolomite

dol.

east

E

cosine

cos

east north east

ENE

cotangent

cot

effervesce (s)

effer.

electromotive

Celsius

C

coulomb

C

cement

cmt

covellite

cv.

force

centimetre

cm

cream

cm.

electron volt

eV

cren.

epidote

ep.

crit.

equation

eqn

centimetre per second

crenulation (ed) cm/s

critical

centipoise

cp

cryptocrystalline

centistokes

cst

crystal

centre line

C/L

crystallized (-ine)

cryst.

centre of gravity

c.g.

cubic centimetre

cm3

centrifugal force

c.f.

cubic centimetre

chalcocite

ct.

per second

chalcopyrite

cp.

cubic metre

chemical

chem.

cryptocryst. xal

cht.

minute

chlorite (ic)

chl.

cubic metre per

equigrannular

evaporation

3

farad

m3

February

cm /s

feldspar m3/min

ferruginous fibrous

3

cl.

hour

m /h

Figure (s)

clayey

cly

cubic millimetre

mm3

fine

clsh.

claystone

clst.

cleavage

cl

coarse cobble coefficient colluvial colour

10

cse cbl. coeff. colluv. col.

current density

dacite (ic) dark day

equiv.wt evapn expt. F Feb. fs. ferr. fib. Fig. (s) f.

c.d.

fissile

Hz

foliation (ed)

fol.

dac.

foraminifera

foram.

cycle per second (frequency)

equiv.

equivalent weight

clay clayshale

eq.

equivalent

experiment (al)

cubic metre per

chert

e.m.f.

flint

dk not abbreviated

formation

fss flt

fm.

fossil (iferous)

foss.

debris

deb.

fracture

fract.

December

Dec

fragment (al)

frag.

Field Geologists’ Manual

ETHICS AND REPORTING

freezing point

f.p.

hour

frequency

Hz

hydrogen ion

friable

fri.

exponent

frosted

fstd

igneous

ign.

litre

gabbro

gab.

ignimbrite

igm.

litre per second

galena

gl.

pH

limestone

lst.

lineation

lin.

liquid

liq.

ilmenite

im.

including

incl.

gt

inclusion

incls.

not abbreviated

indurated

ind.

magnetite

mt.

inferior

inf.

malachite

mal. Mar.

garnet general (ly) glauconite (ic)

gen.

longitude

L L/s

galv.

galvanized gas

h

LOI

low pressure

L.P.

glauc.

inorganic

inorg.

March

gneiss

gns

insoluble

insol.

marl

gossan

gsn

interbedded

gr.

International

grain (ed) gram gram molecule

g g mol.

System Units intraformational

intb. Sl intf.

mar.

massive

mass.

material

mat.

matrix maximum

granite

grt.

Isometric

Iso

granitoid

grtd

island (s)

I. (s.)

granodiorite

gdi.

January

Jan.

megahertz

granofels

gfels

jointing

jtng

granular

grnl.

joule

graphite (ic)

long.

loss on ignition

May medium

mtx max. not abbreviated m. or med. MHz

megohm

MQ

J

melanocratic

mel.

graph.

July

July

melting point

gravel

gr.

June

June

metabasalt

gray

gy

junior

jr.

metamorphic (s)

met. (s)

gn

kaolin

kaol.

metasediment (s)

metased. (s)

green greywacke

gw.

kilogram

kg

metre

gypsum

gyp.

kilojoule

kJ

metre per second

hard

hd

kilometre

km

hardness (Mohs)

H

kilometre per

heavy

hvy

hectare

ha

kilometre per

ht

hour

height hematite henry Hertz heterogeneous

hem. H Hz hetg.

second

km/s

mic.

migmatite (ic)

mig.

milliampere millibar

km/h

milligram

mg

kPa

millilitre

mL

kilovolt

kV

millimetre

mm

kilovolt ampere kilowatt

kVA

million

kW

electron volt

kWh

millisecond

kilpowatt hour

high pressure

H.P.

laminated

high tension

H.T.

laminae

high voltage

H.V.

lamination

homogeneous

homg.

large

lge

horizontal

horiz.

latitude

lat.

minute (angle)

hbl. hflsd

Field Geologists’ Manual

mA mbar

kilopascal

Hex

hornfelsed

m m/s

micaceous

Hexagonal

hornblende

m.p. metabas.

leucocratic light

lam.

leuc. l.

MeV ms

millivolt

mV

milliwatt

mW

mineral

min.

minute (time)

min

molar mole (amount of substance)

M mol

11

ETHICS AND REPORTING

molecule weight

mol.wt

molecular, molecular

mol.

molecules per litre Monoclinic month

plagioclase

plag.

porphyry (itic)

porph.

post meridiem

p.m.

potassium mol./L

feldspar

Mon

potential

not abbreviated

September

Sep.

sediments (s)

sed. (s)

segregated (ions)

seg. (s)

sericite (ic) Kfs

ser.

serpentine (ite)

serp.

shale

sh. shy

difference

p.d.

shaly

motor vessel

m.v.

power factor

P.F.

sht.

mottled

mot.

precipitate

ppt.

siderite

py., shattered

siemens

S

px.

siliceous

sil.

siltstone

slst.

mudstone

mudst.

pyritic (ic)

muscovite (ic)

musc.

pyroxene

mylonite (ic)

mylon.

pyrrhotite

po.

N

qualitative

qual.

quantitative

quant.

Newton nominally north north east north north west

nom. N NE

qtz. qtzte

sid.

sine

sin

slightly

sl.

soft

s.

soluble

sol. soln

radian

rad

solution

radioactive

RA

south

No.

radius

rad.

south east

observed

obs.

rare

October

Oct.

rare earth

oolith

ool.

rare earth oxide

REO

sphalerite

sp.

organic

org.

reconnaissance

reconn.

spherulite

sph.

November number

orthoclase Orthorhombic outcrop page, pages part parts per million

NNW

quartz quartzite

velocity

Nov.

or. Orth

R.

south south west

SSW

RE

specific gravity

sp. gr.

reg.

square

sq.

relative humidity

r.h.

square millimetre

mmZ

o/c

residue

res.

square kilometre

km2

p., pp.

residual

res.

standard error

S.E.

pt

retrograde

ret.

standard

ppm

revolution

rev.

deviation

pascal

Pa

patent

Pat.

pebble (s)

regular

S SE

pbl

revolutions per minute

S.D.

streak rev./min

strk

subordinate

subord.

Rhombohedral

Rho

sulphide

pebbly

pbly

rhyolite

rhy.

system

sys

pegmatite (ic)

peg.

rontgen

r

tabular

tab.

rd.

tangent

tan

per cent in tables

round (ed)

and in the

sand

sd

tesla

experimental

sandstone

ss.

temperature

section of chemical papers

%

per cent in text

not abbreviated

phenocryst (s)

phen.

phosphate (ic)

ph.

phyllite pink

12

phyll. pk

sulph.

T temp.

sandy

sdy

Tetragonal

Tet

saturated

sat.

thin-bedded

tbdd

schist (ose)

sch.

tonne

t

secant

sec

tonne per year

t/yr

secondary

sec.

tonne per day

t/day

second (time)

s

tonne per hour

second (angle)

”

tonne per month

t/h t/month

Field Geologists’ Manual

ETHICS AND REPORTING

trace

tr.

very

v

week

wk wt

west

W

Tric

variable

tuffaceous

tuff.

volcanic (s)

vacuum

vac.

volt

vapour density

v.d.

volume

vapour pressure

v.p.

watt

variety

var.

watt hour

Wh

xenolith (s)

velocity

vel.

weathered

wd

year

yr

yellow

y.

versus

v.

vertical

vert.

weathering weber

var.

weight

Triclinic

volc. (s) V

west north west

vol.

white

W

with

wing.

WNW wh c xens (s)

Wb

Fowler, H W and Fowler, F G (Eds), 1964. The Concise Oxford Dictionary of Current English, 1558 pp (Clarendon: Oxford) provides a list of abbreviations in the forepapers (pp xiv-xvi), and describes the method of abbreviating words, with a further list of abbreviations in Appendix 1 (pp 1525-1540).

1.4.2. ABBREVIATIONS USED IN PETROLEUM EXPLORATION LOGS 1 AND SCOUT REPORTS

A/

acidified with

abd, abnd

abandoned

ac

acres

AS

after shot

pressure shut in bl bld

black bailed

bldg drk

building derrick

bldg rds

building roads

bbl

barrel

b/d

barrels per day

blk

black

barrels

blr

bailer

BCPD

unit BW

barrels water

BWPD

barrels water per

BWPH

barrels water per

day

B/H

bailers per hour

day

BO

barrels oil

C

BOP

blow-out

CBL

cement bond log

preventer

CCL

casing collar log

barrels oil per day

C&P

cellar and pits contract depth

barrels condensate per hour barrels fluid per

BOPD

back pressure

CD

BPD

barrels per day

CFG

BHC

bottom-hole

BPH

barrels per hour

BPWPD

barrels per well

BHP

bottom-hole

BHPF

bottom-hole

choke pressure pressure flowing BHPSI

BP

hour

hour

1.

bottom British thermal

condensate per BCPH

BFPH

btm B.T.U.

per day brkn

centre

cubic feet gas

CFGPD

cubic feet gas per

CGS

centimetre-grams-

day

broken

second

BS

basic sediment

system

BS&W

basic sediment

bottom-hole

chk

choke

and water

Further abbreviations are available from Association of Desk and Derrick Clubs, 1973. D and D Standard Oil Abbreviator, 2nd ed (Penne Will Books, Tulsa, Ok).

Field Geologists’ Manual

13

ETHICS AND REPORTING

circ

circulate or

CI

chloride ion

FDC

circulation clng CO comp

FIH

cleaning

fl/

clean out

fld

completed,

fluor flur

formation density

KO

kicked off

compensated log

KB

Kelly bushing

fluid in hole

LL

laterolog

field

loc

located or

fluorescence

completion

fm

formation

condensate

fos

fossils,

congl

conglomerate

contr

contractor

corr

corner corrected

FP fr E/L GA

CP

casing pressure

gal(s)

CPSI

casing pressure

G&O

shut in crd

cored

crg

coring

G&OCM GC

limestone lease massive

flowing pressure

MCF

thousand cubic

from east line gallons acid

feet MCFGPD

gallon, gallons

thousand cubic feet gas per day

gas and oil

md

gas and oil cut

mi

miles

mud

MI

moving in

gas cut

coarse

GCM

gas cut mud

Centre Section

GCR

gas condensate ratio

CT

cable tools

ggd

gauged

ctg

cuttmg

gge

gauge

dry and

GO

gas odour

abandoned

G/O

gas and ofl

DC

drill collar

GOR

gas-oil ratio

DD

drilling (drilled) deeper

LS, ls lse mass

CSL

D&A

location

fossiliferous

crse

Line

lime

flowed or flowing

cond

cor

li

MICT

millidarcies

moving in cable tools

mil

million

MIM

moving in

MIR

moving in rig

materials MIRT

moving in rotary

MIST

moving in

tools

gr

gray, ground

Gran W

granite wash

MIT

moving in tools

standard tools moving out

DF

derrick floor

grav

gravity

MO

dk

dark

grd

ground

nat

natural

drilled out

grn

green

NL

north line

dol, dolo

dolomite

hd

hard

NS

DP

drill pipe

HFO

hole full oil

D/P

drill plug

HFW

hole full water

drk

derrick

HGOR

drld

drilled

hr(s)

DO

drlg

drilling

DST

drill-stem test

EL elec log, E log elev E of W/L est f

14

h IES

east line electric log elevation

incl

east of west line estimate or

interst

O&GCM

heavy oil hour(s) heavy

igneous

no show oil and gas oil and gas cut mud

O&SW OAW

induction electrical survey

ig

O&G

oil and salt water old abandoned well

OC OCM

oil cut oil cut mud

inclusion,

OF

including

OH

open flow open hole

interstitial

OIH

oil in hole

estimated

IP

initial production

OO

odour oil

fine

Jts

lomts

Ool

oolitic

Field Geologists’ Manual

ETHICS AND REPORTING

op

opaque

R, Rge

O sd

oil sand

rec

recovered

OTD

old total depth

refl

reflection

Sl

OWDD

oil well drilled

refr

refraction

SL

deeper

rmg

reaming

OWPB

old well plugged

rng

runnjng

back

RP

rock pressure

OWWO

oil well worked

RT

rotary table

SO&G

show oil and gas

rigging up cable

SO&W

show oil and

SP

self-potential

over ox

RUCT

oxidized

P

pump

P&A

range

SITP

pressure

SLM

plugged and

rigging up

slight south line steel-line measurement

SO, S/O

tools RUM

shut-in tubing

show oil

water

machine

(electric log)

abandoned

RUP

rigging up pump

spd

spudded

PB

plugged back

RUR

rigging up rotary

squ

squeezed or

PBTD

plugged back

RUST

total depth PD

per day

per

permeability

perf perf csg

rigging up standard tools

sat

saturated or

S/T stds

SC

show condensate

perforated casing

Sd

sand

permeability

SD

shut down

pk

pink

pkr

packer

PL

pipeline

pld

pulled

SDO

shut down for orders

SD rep

shut down for

stn strks sul sul wtr

sand slight show oil sample tops stands stain, stained streaks sulphur sulphur water

sur

survey

repairs

surf

surface

sand showing oil

SW

southwest, salt

S/W

salt water

PLO

pipe-line oil

POL

petroleum-oils-

sdy

sandy

lube

SF

southeast

POOH

Sd SO

SSO

saturation

perforated

perm

squeeze ss

water

pulling out of

Sec

section

swbd

swabbed

hole

sed

sediment

swbg

swabbing

putting on pump

seis

seismograph

SWS

sidewall samples

por

porosity, porous

SG, S/G

ppm

parts per million

SG&C

POP

psi psia

pounds per square

psig

sh

pounds per square

SI

sacks

T

township

SIBHP

shale shut in shut-in

pounds per square

bottom-hole

inch, gauge

pressure

pt PVT

sx

condensate

inch inch, absolute

show gas show gas and

part

SICP

pressure-volume-

qtz qtze

Field Geologists’ Manual

shut-in casing pressure

temperature

Sip

shut-in pressure

quartz

SIS

stopped in sand

quartzite

T/ tbg tbg chk TD temp TP T/Pay TPSI

top tubing tubing choke total depth temporary tubing pressure top pay tubing pressure shut in

T/sd tstg

top sand testing

15

ETHICS AND REPORTING

Twp Twst

township town site

Unconf

unconformity

UR

underreaming

Vis

viscosity

W

W/L

wildcat

W/C

water cushion

wh

white

WI

washing in

WL

water loss

WL

water line

waiting on

WO

waiting on waiting on

Wt

weight

cement to set

WP

working pressure

WOCT WO/O WOR WORT WOST

(cc/min)

16

WOW

WOC, WOCS

water

WC

water load

waiting on cable

weather

Wpstk

tools

wtg

waiting on orders

wtr

waiting on rig waiting on rotary

WW Xin, Xln

whipstock waiting water wash water crystalline

tools

Y

yellow

waiting on

Z

zone

standard tools WOT

waiting on tools

Field Geologists’ Manual

ETHICS AND REPORTING

1.5. SYMBOLS FOR CORRECTING PROOFS

Field Geologists’ Manual

1

17

1.

18

** Amount of space may be indicated.

* Words printed in italics in column below are instructions and not part of the marks.

From Anon., 1988. Style Manual for Authors, Editors and Printers, 4th ed, pp 284-287 (Australian Government Publishing Service: Canberra), by permission.

ETHICS AND REPORTING

Field Geologists’ Manual

ETHICS AND REPORTING

1.6. SELECTED BIBLIOGRAPHY ON WRITING GEOLOGICAL REPORTS Anon, 1995. Style Manual for Authors, Editors and Printers, 5th ed (Australian Government Publishing Service: Canberra). Bates, R L and Jackson, J A (Eds), 1987. Glossary of Geology, 3rd ed (American Geological Institute: Alexandria, VA). Brown, L (Ed), 1993. The New Shorter Oxford English Dictionary, 2 vols (Clarendon Press: Oxford). Cochran, W, Fenner, P and Hill, M (Eds), 1984. Geowriting: A Guide to Writing, Editing and Printing in Earth Science, 4th ed (American Geological Institute: Alexandria, VA). Delbridge, A and Bernard, J R L (Eds), 1992. The Macquarie Concise Dictionary (Macquarie University: Sydney). Druce, E C and Jensen, A R, 1980. BMR Speaker’s Handbook (Australian Government Publishing Service: Canberra). Fowler, H W, 1983. A Dictionary of Modern English Usage, 2nd ed, rev. Sir Ernest Gowers (Oxford University Press: Oxford). Glover, J E, 1992. Style: An Introduction to Writing for Geologists, AIG Handbook 1 (Australian Institute of Geoscientists: Sydney).

Field Geologists’ Manual

Gowers, E, 1986. The Complete Plain Words, 3rd ed, rev. S Greenbaum and J Whitcut (Her Majesty’s Stationery Office: London). Hansen, W R, 1991. Suggestions to Authors of the Reports of the United States Geological Survey, 7th ed (US Government Printing Office: Washington, DC). Kirkpatrick, B (Ed), 1987. Roget’s Thesaurus of English Words and Phrases (Longman: London). Mathison, C I, 1995. Preparation of Geological Reports, Theses and Publications, AIG Handbook 3 (Australian Institute of Geoscientists: Sydney). McKinstry, H E, 1948. Mining Geology (Prentice Hall: New York). O’Connor, T, 1993. Hold the Front Page (Queensland Newspapers: Brisbane). Readers Digest, 1991. Word Finder - A Dictionary of Synonyms and Antonyms (Readers Digest: Sydney). Strunk, W and White, E B, 1979. The Elements of Style, 3rd ed (McMillan: New York). US Bureau of Mines and US Geological Survey, 1997. Dictionary of Mining, Mineral and Related Terms (Engineering and Mining Journal: Chicago, IL).

19

2. MINERAL AND ROCK INFORMATION 2.1. MINERAL INDEX Name

Composition

Xal.Sys.

H

Ag2S . . . . . . . . . . . . NaFe(SiO3)2 Ca2(Mg,Fe)5(Si8O22) (OH)2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MnS . . . . . . . . . . . . Na(AlSi3O8)

Alexandrite Allanite Allemontite Allophane Almandite Altaite Alumstone Alunite Amazonstone Amblygonite Amethyst Amosite Amphibole Group

. . . . . . . . . . . . . . (Ce,Ca,Y) (Al,Fe)3(SiO4)3(OH) AsSb Al2O3.SiO2.nH2O Fe3Al2(SiO4)3 PbTe . . . . . . . . . . . . . . K Al3(SO4)2(OH)6 . . . . . . . . . . . . . . (Li,Na)AlPO4(F,OH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . Mon Hex Amor Iso Iso . . . Rho . . . Tric . . . . . . . . .

Analcime Anatase Anauxite Andalusite

Na (AlSi2O6).H2O TiO2 Al2SiO5

Iso Tet Mon Orth

2.27 3.9 2.6 3.16-3.20

5-5½ 5½-6 2 7½

Andesine Andradite Anglesite

Ab70An30-Ab50An50 Ca3Fe2(SiO4)3 PbSO4

Tric Iso Orth

2.69 3.75 6.2-6.4

6 7 3

Anhydrite Ankerite Annabergite

CaSO4 Ca (Fe, Mg, Mn) (CO3)2 (Ni, CO)3(AsO4)2.8H2O

Orth Rho Mon

2.89-2.98 2.95-3 3.0

3-3½ 3½ 2½-3

Anorthite

CaAl2Si2O8

Tric

2.76

6

Anorthoclase Anthophyllite

(Na,K) AlSi3O8 (Mg,Fe)7(Si8O22) (OH)2

Tric Orth

2.58 2.85-3.2

6 5½-6

Antigorite Antimony Antlerite

. . . . . . . . Sb Cu3SO4(OH)4

. . . . Rho Orth

. . . . 6.7 3.9

Field Geologists’ Manual

. .

. .

. .

. . . . . . . .

. .

Mon . . Mon Mon . . . . . . Iso . . Tric

D

Acanthite Achroite Acmite Actinolite Adularia Aegirine Agate Alabandite Alabaster Albite

7.2-7.3 . . . . . . . 3.40-3.55 3.0-3.2 . . . . . . . . . . . . . . . . . . . . . 4.0 . . . . . . . 2.62 .

. . . . . 3.5-4.2 5.8-6.2 1.85-1.89 4.25 8.16 . . . . . . 2.6-2.8 . . . . . . 3.0-3.1 . . . . . . . . . . . . . . . . . .

2-2½ . 6-6½ 5-6 . . . 3½-4 . 6 . 5½-6 3-4 3 7 3 . 4 . 6 . . .

. . 3 3½-4

Remarks Low temp. Ag2S, 87% Ag Colourless tourmaline A pyroxene Tremolite with >2% Fe Clear orthoclase Impure acmite Banded chalcedony Black Massive f.gr. gypsum Na rich plagioclase, Ab100 to Ab90 An10 Gem chrysoberyl About 28% REO One cleavage Claylike mineral A red garnet Tin-white, rare Alunite 11.4% K2O, 37% Al2O3 Green microcline About 10% Li2O, 48% P2O5 Purple quartz Anthophyllite asbestos See Actinolite, Anthophyllite, Arfvedsonite, Cummingtonite, Glaucophane, Hornblende, Riebeckite, Tremolite A zeolite Low temp. TiO2 Si-rich kaolinite Often as square prisms. 63% Al2O3 A plagioclase feldspar Calcium-iron garnet Secondary, often banded. 68% Pb 41% CaO Dolomite with Fe>Mg Nickel bloom. 29% Ni, 25% As Ca-rich plagioclase, An100 to An90 Ab10 Like orthoclase, with Na>K Clove brown amphibole var. of asbestos Platy serpentine Cl (0001) Secondary Cu mineral of arid regions

21

MINERAL AND ROCK INFORMATION

Name

Composition

Xal.Sys.

D

H

Remarks

Apatite Apophyllite Aquamarine Aragonite Arfvedsonite Argentite Arsenic Arsenopyrite Asbestos

Ca5(PO4,CO3)3(F, OH, Cl) KCa4Si8O20(F,OH).8H2O . . . . . . . . . . . . . . CaCO3 Na2–3(Fe,Mg,Al)5Si8O22 (OH)2 Ag2S As FeAsS . . . . . . . . . . . . . .

Hex 3.15-3.20 Tet 2.3-2.4 . . . . . . . . . Orth 2.95 Mon 3.45 Iso 7.3 Rho 5.7 Mon 5.9-6.2 . . . . . . . . .

5 4½-5 . 3½-4 6 2-2½ 3½ 5½-6 .

Asbolite Atacamite Augite

Amor Orth Mon

2.9-4.3 3.75-3.77 3.2-3.4

3-3½ 5-6

Aurichalcite Autunite

Cobaltian wad Cu2Cl(OH)3 (Ca,Na)(Mg,Fe2+,Fe3+, Al)(Si,Al)2O6 (Zn,Cu)5(CO3)2(OH)2 Ca(UO2)2(PO4)2.10-12H2O

Mon Tet

3.2-3.7 3.1-3.2

2 2-2½

Awaruite Axinite Azurite

FeNi2 (Ca,Mn,Fe)3Al2BSi4O15(OH) Cu3(CO3)2(OH)2

Iso Tric Mon B

8 3.27-3.35 3.77

4-5 6½-7 3½-4

Baddeleyite Balas ruby Barite Barytes Bastnaesite Bauxite

Mon 5.5-6 6.5 (Zr,Hf)O2 . . . . . . . . . . . . . . . . . . . . . . . . BaSO4 Orth 4.5 3-3½ . . . . . . . . . . . . . . . . . . . . . . . . (Ce,La)(CO3)(F,OH) Hex 4.9-5.2 4-4½ . . . . . . . . . . . . . . . . . . . . . . . .

Beidellite Bentonite Beryl Biotite

2.6 1½ . . . . . . 2.75-2.8 7½-8 2.8-3.2 2½-3

Bismite Bismuth Bismuthinite Bismutite

Al8(Si4O10)3(OH)12.12H2O Orth? . . . . . . . . . . . . . . . . . . Be3Al2(Si6O18) Hex K(Mg,Fe2+)3(Al, Fe3+) Mon Si3O10(OH)2 Bi2O3 Mon Bi Rho Bi2S3 Orth (BiO2)CO3 Tet

Minor Zr source Red gem spinel Cl (00l), (110). 65.7% BaO Barite 75% REO A mixture of aluminium hydroxides Al-rich montmorillonite Largely montmorillonitc 14% BeO Common black mica

8 9.8 6.75-6.81 6.1-7.7

72% Bi Cl (0001) Cl (010). 81% Bi 75% Bi

Black Jack Blende Bloodstone Blue vitriol Boehmite Boracite Borax Bornite

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AlO(OH) Mg3B7O13Cl Na2B4O7.10H2O Cu5FeS4

. . . . . . . . . . . . . . . . . . . . 3.01-3.06 2.9-3.0 7 1.7 2-2½ 5.06-5.08 3

Boulangerite Bournonite

Pb5Sb4S11 PbCuSbS3

22

. . . .

. . . .

. . . .

. . . .

. . . .

. . . .

. . . . . . . . Orth Orth Mon Iso Orth Orth

. . . .

. . . .

6-6.3 5.8-5.9

4½ 2-2½ 2 2½-3 ½ . . . .

2½-3 2½-3

38-42% P2O5 Secondary, in basic lavas Pale greenish-blue transparent beryl Cl (010), (110). 56% CaO Na amphibole Sectile, 87% Ag Cl (0001) Pseudo-orth. 46% As See Amosite, Anthophyllite, Chrysotile, Crocidolite, Tremolite To 15% Co Cl (010). 59% Cu Common pyroxene 14-23% Cu, 36-47% Zn Yellow-green, fluorescent, 67% U3O8 Magnetic Crystal angles acute Always blue. 55% Cu

Sphalerite Sphalerite Heliotrope Chalcanthite In bauxite. 85% Al2O3 62% B2O3 Cl (100). 36.5% B2O3 Purple-blue tarnish. 63.3% Cu 55% Pb, 25% Sb Easily fusible. 13% Cu, 42% Pb, 25% Sb

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

Name

Composition

Xal.Sys.

D

H

Remarks

Brannerite

(U,Ca,Ce)(Ti,Fe)2O6

?

4.5-5.4

4½

30-50% U3O8

Braunite

3Mn2O3.MnSiO3

Tet

4.8

6-6½

64% Mn

Bravoite

(Ni,Fe)S2

Brazilian emerald

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Green tourmaline

Brittle mica

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

See Chloritoid, Margarite,

Brochantite

Cu4(OH)6SO4

Mon

3.9

3½-4

Green. 56% Cu

Bromyrite

Ag(Br,Cl) with Br>Cl

Iso

6-6.5

2½

Sectile. 57-65% Ag

Bronzite

(Mg,Fe)SiO3

Orth

3.1-3.3

5½

Enstatite with 5-13% FeO

Brookite

TiO2

Orth

3.9-4.1

5½-6

Adamantine lustre

Brucite

Mg(OH)2

Rho

2.39

2½

Cl (0001). 69% MgO

Bytownite

Ab30An70-Ab10An90

Tric C

2.74

6

A plagioclase feldspar

Cairngorm

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Smoky to black quartz

Calamine

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Hemimorphite

Calaverite

AuTe2

Mon

9.35

2½

Easily fusible. 42% Au

Calcite

CaCO3

Rho

2.72

3

Fluorescent, Cl (1011), 56% CaO

Californite

. .

Calomel

Hg2Cl2

Tet

7.2

1½

85% Hg

Cancrinite

(Na2,Ca)4(AlSiO4)6CO3. nH2O

Hex

2.45

5-6

A feldspathoid

Capillary pyrites

. .

Carnallite

KMgCl3.6H2O

Carnelian

. .

Carnotite

K2(UO2)2(VO4)2.3H2O

Orth

4.1

Soft

50% U3O8, 20% V2O5

Cassiterite

SnO2

Tet

6.8-7.1

6-7

Lustre adamantine. 78.6% Sn

Iso

4.66

5½-6

Steel gray. 24% Ni

Ottrelite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Orth . .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

1.6 . .

. .

. .

. .

. .

. . 1

. .

. .

. .

. .

Gem idocrase

Millerite Deliquescent. 16.8% K2O, 14.6% MgO Red chalcedony

Cat's-eye

. .

Celestite

SrSO4

Orth

3.95-3.97

3-3½

Gem var. of chrysoberyl or quartz 56% SrO

Celsian

BaAl2Si2O8

Mon

3.37

6

Feldspar with 41% BaO

Cerargyrite

Ag(Cl,Br) with Cl>Br

Iso

5.5-6

2½

Perfectly sectile. 65-75% Ag

Cerussite

PbCO3

Orth

6.55

3-3½

Effer. in HNO3. 77% Pb

Cervantite

Sb2O4

Orth?

4.0-5.0

4-5

After stibnite. 79% Sb

Chabazite

Ca(Al2Si4O12).6H2O

Rho

2.05-2.15

4-5

Cube-like zeolite crystals

Chalcanthite

CuSO4.5H2O

Tric

2.12-2.30

2½

Soluble in water. 35% Cu

Chalcocite

Cu2S

Orth

5.5-5.8

2½-3

Imperfectly sectile. 79.8% Cu

Chalcopyrite

CuFeS2

Tet

4.1-4.3

3½-4

Brittle, yellow. 3l-34.5% Cu

Chalcotrichite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Fibrous cuprite

Chalk

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Fine grained calcite

Chalybite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Siderite

Chert

SiO2

Chessylite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Azurite

Chiastolite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Andalusite with dark cruciform inclusions

Chloanthite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Nickel skutterudite, 3.5-6.5% Co 14.5-21.5% Ni , 71.5-73.5% As

Chlorargyrite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

AgCl, 75% Ag, member of cerargyrite series

Chalcedony

Field Geologists’ Manual

2.6-2.64

2.65

Cryptocryst. quartz

7

Cryptocryst. quartz

23

MINERAL AND ROCK INFORMATION

Name

Composition 2+

Xal.Sys.

3+

D

H

Remarks

Chlorite

(Mg,Fe ,Fe )6 ALSi3O10(OH)8

Mon

2.6-2.9

2-2½

Differentiated by chem. analyses and optical properties into Clinochlore, Penninite and Prochlorite

Chloritoid

Fe2Al4Si2O10(OH)4

Mon

3.5

6-7

Brittle mica

Chondrodite

(Mg,Fe)3SiO4(OH,F)2

Mon

3.1-3.2

6-6½

Similar species are Clinohumite, Humite, Norbergite

Chromite

(Fe,Mg)O.(Fe,Al,Cr)2O3

Iso

4.3-4.6

5½

Lustre submetallic, dark brown streak. 43-68% Cr2O3

Chrysoberyl

BeAl2O4

Orth

3.65-3.8

8½

Crystals tabular. 19.8% BeO

Chrysocolla

Cu2H2(Si2O5)(OH)4

?

2.0-2.4

2-4

Chrysolite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Olivine

Chrysoprase

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Green chalcedony

Chrysotile

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Serpentine asbestos

Rho

8.10

2½

Bluish green. 36% Cu

Cinnabar

HgS

Cinnamon stone

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Grossularite

Red streak. 86% Hg

Citrine

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Pale yellow quartz

Clay

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

See Kaolin, Montmorillonite, Illite

Cleavelandite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

White, platy albite

Cliachite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Very fine grained to colloidal Al hydroxides in bauxite

Clinochlore

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Chlorite variety

Clinoclase

Cu3(AsO4)(OH)3

Mon

4.38

2½-3

Sec. mineral

Clinoenstatite

(Mg,Fe) SiO3

Mon

3.19

6

Monoclinic form of enstatite

Clinoferrosilite

(Fe,Mg) SiO3

Mon

3.6

6

A pyroxene

Clinohumite

Mg9Si4O16(F, OH)2

Mon

3.1-3.2

6

Chondrodite group

Clinozoisite

Ca2Al3Si3O12(OH)

Mon

3.25-3.37

6-6½

Crystals striated

Cobaltite

CoAsS

Iso

6.33

5½

In pyritohedrons. 29-35% Co, 43-45% As

Coffinite

U(SiO4)1-x(OH)4x

Tet

7.2

Cogwheel ore

. .

Colemanite

Ca2B6O11.5H2O

Collophane

. .

Columbite

(Fe,Mn)(Nb,Ta)2O6 with Nb>Ta

Common salt

. .

Copper

Cu

Copper glance

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Chalcocite

Copper nickel

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Niccolite

Copper pyrites

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Chalcopyrite

Cordierite

(Mg,Fe)2Al4Si5O18

Orth

2.60-2.66

7-7½

In m. to high grade metamorphics

Corundum

Al2O3

Rho

4.02

9

Rhomb. parting 52.9% Al

Cotton-balls

. .

Covellite

CuS

Cristobalite

SiO2

24

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Mon . .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. . Hex

. .

. .

. .

. .

. .

8.9

. .

. .

. .

Bournonite

. . 6 . . 2½-3

. .

4.6-4.76 2.30

Black U mineral of sed/sandst. deps.

4-4½

5.2-6.7

Iso

. .

. .

2.42

Orth . .

. .

. .

. . 1½-2

Cl (010) perfect. 50.9% B2O3 Massive apatite of rock phosphate deposits Lustre submetallic. 31-79% Nb2O5, max 52% Ta2O5 (with Nb = Ta) Halite Malleable

Ulexite Blue. 66.4% Cu High temp. quartz, in volcanic rocks (> 1470°C)

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

Name

Composition . .

. .

. .

. .

Xal.Sys. . .

. .

. .

D

H

3.2-3.3

Remarks

Crocidolite

. .

Crocoite

PbCrO4

Mon

5.9-6.1

2½-3

Blue asbestos variety of riebeckite Orange-red streak. 23% Cr2O3, 64% Pb

Cryolite

Na3AlF6

Mon

2.95-3.00

2½

White. 54.4% F

Cubanite

CuFe2S3

Orth

4.03-4.18

3½

23% Cu

Cummingtonite

(Fe,Mg)7(Si8O22)(OH)2

Mon

3.1-3.6

6

An amphibole

Cuprite

Cu2O

3½-4

Brownish red streak. 88.8% Cu

Cyanite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Kyanite

Cymophane

. .

. .

. .

. .

. .

. .

. .

. . . . D

. .

. .

. .

Chrysoberyl

Danaite

(Fe,Co)AsS

Mon

5.9-6.2

5½-6

Cobaltian arsenopyrite, to 12% Co

Danburite

CaB2(SiO4)2

Orth

2.97-3.02

7

In crystals. 28.4% B2O3

Datolite

CaB(SiO4)(OH)

Mon

2.8-3.0

5-5½

Usually in crystals. 21.8% B2O3

Davidite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Th brannerite. To 9% U3O8

Demantoid

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Green gem andradite

Diallage

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Diopside with (100) parting

Diamond

C

Iso

3.5

10

Adamantine lustre, fluorescent

Diaspore

AlO(OH)

Orth

3.35-3.45

6½-7

85% Al2O3

Diatomite

. .

. .

. .

. .

. .

. .

. .

. .

0.4-0.6

2

Siliceous tests of diatoms

Dichroite

. .

. .

. .

. .

. .

. .

. .

. .

Dickite

Al2Si2O5(OH)4

Mon

Digenite

Cu9S5

Diopside

CaMg(SiO3)2

Dioptase

CuSiO2(OH)2

Disthene

. .

Dolomite

CaMg(CO3)2

Iso

6.0

(2.2)

. .

. .

. .

. .

. .

. .

. .

Cordierite

2.6

2-2½

Kaolin group clay mineral

Iso

5.6

2½-3

With chalcocite. 75-79% Cu

Mon

3.2-3.3

5-6

A pyroxene

Rho

3.3

5

Emerald green

. . 3½-4

Kyanite

. .

Rho

Dry-bone ore

. .

Dumortierite

(Al,Fe)7O3(BO3) (SiO4)3

. .

. .

. .

. .

. .

. .

(5½-6½) . .

. .

. .

. .

. .

. .

2.85

. .

Orth

. .

. .

. .

Cl (1011). 30.4% CaO, 21.7% MgO, 54.3% CaCO3

. .

Smithsonite

3.26-3.36

7

Radiating fibrous Pale iron-free hornblende

E Edenite

Ca2NaMg5(AlSi7O22) (OH)2

Mon

3.0

6

Electrum

Au,Ag

Iso

13.5-17.5

3

Natural Au-Ag alloy with >20% Ag

Eleolite

. .

. .

Nepheline

Embolite

Ag(Cl,Br) with Cl = Br

1-1½

Intermediate between cerargyrite and bromyrite

Emerald

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Green gem beryl

Emery

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Corundum with magnetite

Enargite

Cu3AsS4

Endlichite

. .

Enstatite

MgSiO3

Orth

3.2-3.5

5½

A pyroxene

Epidote

Ca2(Al,Fe) 3Si3O12 (OH)

Mon

3.35-3.45

6-7

Cl (001)

Epsomite

MgSO4.7H2O

Orth

1.75

2-2½

Bitter taste. 16.3% MgO

Epsom salt

. .

. .

Epsomite

Erythrite

Co3(AsO4)2.8H2O

Essonite

. .

Field Geologists’ Manual

. .

. .

. . . .

. .

. .

. .

. .

. .

. .

Iso

. . . .

. .

. . . .

. .

. .

. .

. .

. .

. .

. .

. .

Mon . .

. .

. .

. .

. .

5.6

Orth . .

. .

. .

4.43-4.45 . .

. .

. .

. .

. .

. .

2.95 . .

. .

. .

3

Cl (110). 48.3% Cu, 19.1% As

. .

Arsenical vanadinite, As replacing V

1½-2½

Pink cobalt bloom. 37% Co

. .

Grossularite

25

MINERAL AND ROCK INFORMATION

Name

Composition

Xal.Sys.

D

Euclase

BeAlSiO4(OH)

Mon

3.1

Eucryptite

LiAlSiO4

Hex

2.67

Euxenite

AB2O6, A = Y, Ce, Ca, U, Th; B = Ti, Nb, Ta, Fe

Orth

5-5.9

H

Remarks

7½

Cl (010). 17% BeO

5½-6½

22-30% REO, max. 8% U3O8, 30-50% (Nb2O5+Ta2O5)

After spodumene, fluorescent

F Fahlore

. . . .

Fayalite

Fe2SiO4

. .

. .

. .

. .

Feather ore

. . . .

Feldspar Group

MAl(Al,Si)3O8, M = K, Na, Ca, Ba, Rb, Sr, Fe

Feldspathoid Group

. . . .

. .

. .

. .

. .

Orth . .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

4.14 . .

. .

Tetrahedrite 6½

. .

Iron olivine Jamesonite See Plagioclase, Potassium Feldspar, Celsian

. .

. .

. .

. .

. .

. .

See Cancrinite, Lazurite, Leucite, Nepheline, Petalite, Sodalite

Ferberite

FeWO4

Mon

7.5

5

Wolframite series, 76.3% WO3

Fergusonite

(RE,Fe)(Nb,Ta,Ti) O4

Tet

4.2-5.8

5½-6½

Max. 46% REO, 10% U3O8, 54% Nb2O5 39% Mo

Ferrimolybdite

Fe2(MoO4)3.8H2O?

Orth?

3

1½

Ferrosilite

FeSiO3

Orth

3.6

6

Fibrolite

. . . .

Flint

SiO2

Florencite

CeAl3(PO4)2(OH)6

Flos ferri

. .

Fluorite

CaF2

Formanite

. .

Forsterite

Mg2SiO4

Fowlerite

. .

Franklinite

(Fe2+, Zn, Mn2+) (Fe3+, Mn3+)2O4

Freibergite

. .

Fuchsite

K(Al,Cr)2(Al,CrSi3O10)(OH)2

Mon G

2.76-2.88

Gadolinite

Be2FeY2Si2O10

Mon

4.0-4.5

6½-7

Nom. 48% REO, 10% BeO

Gahnite

ZnAl2O4

Iso

4.55

7½-8

Zn spinel, green octahedrons

Galaxite

MnAl2O4

Iso

4.03

7½-8

Mn spinel

Galena

PbS

Iso

7.4-7.6

2½

Cl cubic. 86.6% Pb

Garnet Group

A3B2(SiO4)3 A = Ca, Mg, Fe2+, Mn2+;

Iso

3.5-4.3

6½-7½

See Almandite, Andradite, Grossularite, Pyrope, Spessartite, Uvarovite

. . . . . . . .

. .

. .

. .

. .

. .

. .

. .

. .

Hex

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Iso . .

. .

. .

. .

. .

. .

. .

7

3.6

5

. . . . . .

. .

. .

Cryptocryst. quartz Pale yellow Arborescent aragonite

4 . .

Cl octahedral, fluorescent, 48.9% F Fergusonite with Ta>Nb

6½ . .

5.15 . .

A pyroxene Fibrous sillimanite

2.65

3.2 . .

Iso . .

. .

3.18 . .

Orth . .

. .

Magnesian olivine Zinc-bearing rhodonite

6 . .

Dark brown streak, 5-19% Zn. Argentiferous tetrahedrite

2-2.5

B = Al, Fe3+, Mn3+, Cr.

Cr rich muscovite

Garnierite

(Ni,Mg)3Si2O5(OH)4?

Amor

2.2-2.8

2-3

Green. 25-30% Ni

Gaylussite

Na2Ca(CO3)2.5H2O

Mon

1.99

2-3

Easily fusible. 20% Na2O

Gedrite

. .

Geocronite

Pb5(Sb,As)2S8

Orth

6.3-6.5

2½

69% Pb, 8% Sb, 5% As

Gersdorffite

NiAsS

Iso

5.9

5½

35% Ni, 45% As

Geyserite

. .

Gibbsite

Al(OH)3

Mon

2.3-2.4

2½-3½

Glauberite

Na2Ca(SO4)2

Mon

2.70-2.85

2½-3

Glaucodot

. .

Glauconite

(K,Na)(Al, Fe3+, Mg)2 (Al,Si)4O10(OH)2

26

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. . Mon

. .

. .

. .

. .

. .

. . 2.3

. .

Al-rich anthophyllite

. .

Opal of hot spring deposits

. .

65.4% Al2O3 22% Na2O Danaite

2

Green sand mica of marine sediments

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

Name

Composition

Xal.Sys.

2+

D

H

Remarks

Glaucophane

Na2(Mg,Fe )3Al2Si8O22 (OH)2 Mon

3.0-3.2

6-6½

Na amphibole

Gmelinite

(Na2,Ca)Al2Si4O12.6H2O

Rho

2.04-2.17

4½

Var. of chabazite

Goethite

FeO(OH)

Orth

4.37

5-5½

Cl (010), 62% Fe

Gold

Au

Iso

15.0-19.3

2½-3

Yellow, soft

Goslarite

ZnSO4.7H2O

Orth

1.98

2-2½

Sol. in water. 22% Zn

Graphite

C

Hex

2.3

l-2

Black, platy

Grey copper

. .

Greenockite

CdS

Hex

4.9

3-3½

Grossularite

Ca3Al2(SiO4)3

Iso

3.53

6½

A garnet

Gummite

UO3.nH2O

3.9-6.4

2½-5

Field name for hydrous U oxides. 60-80% U3O8

Gypsum

CaSO4.2H2O

2.32

2

Cl (010), (100), (011). 32.5% CaO

. .

. .

. .

. .

. .

. .

. .

. .

Mon H

2.16

2½

53% Na2O equiv.

Halloysite

Al2Si2O5(OH).nH2O

Amor

2.0-2.2

1-2

Clay mineral

Harmotome

(Ba,K)(Al, Si)2Si6O16.6H2O

Mon

2.45

4½

A stilbite group zeolite

Hastingsite

(Na,Ca)2(Fe,Mg) 5Al2Si6O22 (OH)2

Mon

3.2

6

Hornblende series

Hausmannite

Mn3O4

Tet

4.84

5½

72% Mn

Hauynite

(Na,Ca)4–8Al6Si6O24. (SO4, S)1–2

Iso

2.4-2.5

5½-6

A feldspathoid

. .

Ni3S2

Hectorite

(Mg,Li)6Si8O20(OH)4

Hedenbergite

CaFe(Si2O6)

Heliotrope

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Mon Mon

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Hematite

Barite

4.6

5

Brassy yellow, to 73% Ni

2.5

1-1½

Li montmorillonite

3.55 . .

. .

Yellow-orange. 77.8% Cd

Iso

Heazlewoodite

. .

Tetrahedrite

. .

Heavy spar

. .

. .

NaCl

. .

. .

. .

Halite

. .

. .

. .

Haematite

. .

. .

. .

. .

5-6 . .

. .

End member of diopside series Green and red chalcedony

Helvite

(Mn,Fe,Zn)4Be3(SiO4)3S

Iso

3.16-3.36

6-6½

In pegmatites

Hematite

Fe2O3

Rho

5.26

5½-6 ½

Brownish red streak. 70% Fe

Hemimorphite

Zn4(Si2O7)(OH)2.H2O

Orth

3.4-3.5

4½-5

Cl (110). 54% Zn

Hercynite

FeAl2O4

Iso

4.39

7½-8

Iron spinel

Hessite

Ag2Te

Iso

8.4

2½-3

Grey

Heulandite

(Na,Ca)4-6Al6(Al,Si)4Si26 O72.24H2O

Mon

2.18-2.20

3½-4

A zeolite

Hiddenite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Green spodumene

Holmquistite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Lithium-bearing glaucophane

Hornblende

Ca2Na(Mg,Fe2+)4(Al, Fe3+,Ti)AlSi8O22(O,OH)2

Horn silver

. .

. .

. .

. .

. .

. .

Mon . .

. .

3.2 . .

. .

5-6 . .

. .

Huebnerite

MnWO4

Mon

7.0

5

Humite

Mg7(SiO4)3(F,OH)2

Orth

3.1-3.2

6

Hyacinth

. .

. .

. .

. .

. .

. .

. .

Hyalite

. .

. .

. .

. .

. .

. .

. .

Hyalophane

(K,Ba)Al(Al,Si)3O8

Hydromica

. .

Field Geologists’ Manual

. .

. .

. .

. .

. .

Cerargyrite Wolframite series. 76.6% WO3 Chondrodite group

. .

. .

. .

. .

. .

Brownish to red-orange zircon

. .

. .

. .

. .

. .

Globular, colourless opal

Mon . .

Common amphibole

. .

2.8 . .

. .

6 . .

. .

Ba-rich orthoclase Illite

27

MINERAL AND ROCK INFORMATION

Name

Composition

Xal.Sys.

D

H

Remarks

Hydrozincite

Zn5(CO3)2(OH)6

Mon

3.6-3.8

2-2½

Secondary mineral. 59% Zn

Hypersthene

(Mg,Fe)SiO3

Orth

3.4-3.5

5-6

A pyroxene

I Hex

1½

Ice

H2O

Iceland spar

. .

Iddingsite

H8Mg9Fe2Si3O14?

Orth

3.5-3.8

3

After olivine

Idocrase

Ca10(Mg,Fe)2Al4(SiO4)5 (Si2O7)2(OH)4

Tet

3.35-3.45

6½

Prismatic crystals

Illite

Hyd.Al, K, Ca, Mg silicate

. .

. .

. .

Ilmenite

FeTiO3

Ilmenorutile

(Ti,Nb,Fe)3O6

. .

. .

. .

0.917

. .

. .

3+

. .

. .

2Fe

. .

. .

Optically clear calcite

Mica-like clay mineral, about 38% Al2O3 Rho

2+

. .

(SiO4)2(OH)

Orth

4.7

5½-6

Slightly magnetic. 52.6% TiO2

5.1

6-6.5

Black, end member of struverite series

4.0

5½-6

Black or brown

Ilvaite

CaFe

Indicolite

. .

Iodobromite

Ag(Cl,Br,I)

Iso

5.7

1-1½

Iodyrite

AgI

Hex

5.7

1-1½

Iolite

. .

Iridium

Ir

Iso

22.7

6-7

Platinoid metal

Iridosmine

Ir, Os

Rho

19.3-21.1

6-7

Platinoid. Max. 77% Ir, max. 80% Os

Iron pyrites

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Dark blue tourmaline To about 15% I, 60% Ag Sectile. 45% Ag Cordierite (gem var.)

. .

Pyrite

. . 5.5-6.5

Hyacinth

. .

See nephrite and jadeite

J Jacinth

. .

Jacobite

MnFe2O4

. .

Jade

. .

Jadeite

Na(Al,Fe)Si2O6

Mon

3.3-3.5

6½-7

Jamesonite

Pb4FeSb6S14

Mon

5.5-6.0

2-3

Jargon

. .

. .

. .

. .

. .

. .

. .

. .

. . Iso

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Jarosite

KFe3(SO4)2(OH)6

Jasper

. .

Kainite

MgSO4.KCl.3H2O

Kalinite

. .

Kaliophilite

K(AlSiO4)

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Rho

. . . . 4.75 . .

. .

. .

. .

2.91-3.26

. . . . K Mon . .

. .

Hex

. .

3

. .

. .

. .

. .

2.1 . .

. .

3

2.61

6

A black magnetic spinel Green pyroxene jade 50.8% Pb, 29.5% Sb Clear, yellow or smoky zircon 6-9% K2O Red cryptocryst. quartz 19% K2O, 16% MgO Potash Alum Dimorph. with kalsilite. 30% K2O, 32% Al2O3

Kalsilite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

End member of nepheline series

Kaolin Group

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Family of clay minerals, see Anauxite, Dickite, Kaolinite, Nacrite, with 39.5% Al2O3

Kaolinite

Al2(Si2O5)(OH)4

Mon

2.6-2.65

2-2½

Kernite

Na2B4O7.4H2O

Mon

1.95

3

22.7% Na2O, 51% B2O3

Krennerite

AuTe2

Orth

8.62

2-3

Basal cleavage

Kunzite

. .

Kyanite

Al2SiO5

. .

. .

. .

. .

. .

. .

. . Tric

. .

. .

. .

. .

Earthy

Pink spodumene

3.56-3.66

5-7

Blue, Cl (100) perfect, bladed xals. Marked hardness anisotropy

L Labradorite

Ab50An50-Ab30An70

Tric

2.71

6

A plagioclase feldspar

Langbeinite

K2Mg2(SO4)3

Iso

2.83

2½-3½

22.7% K2O, or 42% K2SO4

28

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

Name

Composition . .

. .

. .

. .

Xal.Sys. . .

. .

. .

. .

D . .

. .

H . .

Remarks

Lapis lazuli

. .

Larsenite

PbZnSiO4

Orth

5.9

3

Impure lazurite Rare olivine A zeolite

Laumontite

(Ca,Na)Al2Si4O12.4H2O

Mon

2.28

4

Lawsonite

CaAl2(Si2O7)(OH)2.H2O

Orth

3.09

8

In gneisses and schists

Lazulite

(Mg,Fe3+)Al2(PO4)2(OH)2

Mon

3.0-3.1

5-5½

Blue gemstone

Lazurite

(Na,Ca)4(AlSiO4)3 (SO4,S,Cl)

Iso

2.4-2.45

5-5½

A feldspathoid

Lechatelierite

SiO2

Amor

2.2

6-7

Fused silica

Lepidocrocite

FeO(OH)

Orth

4.09

5

With goethite. 62% Fe

Lepidolite

K(Li,Al)3(Si,Al)4O10 (F,OH)2

Mon

2.8-3.0

2½-4

Lithium mica with about 5% Li2O

Iso?

2.45-2.50

5½-6

Leucite

K(AlSi2O6)

Leucoxene

FeTiO3 to TiO2

Libethenite

Cu2(PO4)(OH)

Orth

4

4

53% Cu, 29% P2O5

Limonite

FeO(OH).nH2O

Amor

3.6-4.0

5-5½

Field name for brown amorphous hydrous iron oxides, yellowish brown streak, about 60% Fe

Linarite

PbCu(SO4)(OH)2

Mon

5.3

2½

Deep blue. 15% Cu, 51% Pb

Linnaeite

Co3S4

Iso

4.8

4½-5 ½

58% Co, to 7% Ni

Lithia mica

. .

. .

. .

2+

. .

3.6-4.3

. .

. .

. .

2+

. .

. .

. .

. .

A feldspathoid Whitish, opaque ilmenite alteration products

. .

Lepidolite

Lithiophilite

Li(Mn , Fe )PO4

Orth

3.5

5

End member of triphylite series. 9.5% Li2O, 45% P2O5

Loellingite

FeAs2

Orth M

7.4-7.5

5-5½

72.8% As

Magnesiochromite

(Mg,Fe)(Cr,Al)2O4

Iso

4.2

5½

End member of chromite series, with 21% MgO, 79% Cr2O3

Magnesioferrite

(Mg,Fe)Fe2O4

Iso

4.5

5½-6 ½

A spinel. 20% MgO, 56% Fe for MgFe2O4

Magnesite

MgCO3

Rho

3.0-3.2

3½-5

Commonly massive, sticks to the tongue, 47.6% MgO

Magnetic pyrites

. .

Magnetite

(Fe,Mg)Fe2O4

Iso

5.18

6

Iron spinel, strongly magnetic, blk. streak. 72.4% Fe for Fe3O4

Malachite

Cu2CO3(OH)2

Mon

3.9-4.03

3½-4

Green. 57.3% Cu

Manganite

MnO(OH)

Orth

4.3

4

Prismatic crystals, dark brown streak. 62% Mn

Manganosite

MnO

Iso

5.0-5.4

5½

77% Mn

Manganotantalite

(Mn,Fe)(Ta,Nb)2O6

Orth

7.3

4½

Tantalite with Mn: Fe :: 3:1, 10% Mn, 84% (Nb2O5+Ta2O5)

Marcasite

FeS2

Orth

4.89

6-6½

White iron pyrites. 46.5% Fe

Margarite

CaAl2(Al2Si2O16)(OH)2

Mon

3.0-3.1

3½-5

A brittle mica

Marialite

3NaAlSi3O8.NaCl

Tet

2.7

5½-6

End member of scapolite series

Marmatite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Iron rich sphalerite, to 20% Fe

Martite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Hematite octahedrons after magnetite

Meerschaum

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Sepiolite

Meionite

3CaAl2Si2O8.CaCO3

Field Geologists’ Manual

. .

. .

. .

. .

. .

. .

. .

Tet

. .

. .

2.7

. .

. .

5½-6

Pyrrhotite

End member of scapolite series

29

MINERAL AND ROCK INFORMATION

Name

Composition

Xal.Sys.

D

H

Remarks

Melaconite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Tenorite

Melanite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Black andradite

Melanterite

FeSO4.7H2O

Mon

1.90

2

Melilite

(Na,Ca)2(Mg,Al)(Si,Al)2O7

Tet

2.9-3.1

5

Menaccanite

. .

Meneghinite

CuPb13Sb7S24

. .

. .

. .

. .

. .

. .

. .

. .

Orth

. .

. .

6.36

. . 2½

13.6

Green-blue Ilmenite Jamesonite family

Mercury

Hg

Miargyrite

AgSbS2

Mica Group

. .

Microcline

K(AlSi3O8)

Tric

2.54-2.57

6

Triclinic K feldspar

Microlite

(Na,Ca)2(Ta,Nb)2O6(O,OH,F)

Iso

6.33

5½

End member of pyrochlore series, 75-80% (Nb2O5+Ta2O5)

Microperthite

. .

Millerite

NiS

Rho

5.3-5.7

3-3½

Capillary crystals 64.7% Ni

Mimetite

Pb5Cl(AsO4)3

Hex

7.0-7.2

3½

Like pyromorphite. 69% Pb, 15% As

Minium

Pb3O4

Mispickel

. .

Molybdenite

MoS2

. .

. .

. . . .

Mon . .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Fluid, quicksilver

5.2-5.3 . .

. .

. .

. .

. .

. .

8.9-9.2 . .

. .

. .

. .

. .

. .

. .

Hex . .

. .

. .

. .

. .

. .

. .

. .

4.62-4.73 . .

. .

. .

2½ . .

. .

2½ . . 1-1½ . .

Cherry red streak. 36% Ag, 41% Sb See Biotite, Brittle Mica, Lepidolite, Muscovite, Phlogopite

Microcline and albite micro layers

90% Pb Arsenopyrite Platy. 60% Mo

Molybdite

. .

Monazite

(Ce,La,Y,Th)(PO4,SiO4)

Mon

5.0-5.3

5-5½

Ferrimolybdite Max. 30% ThO2, max. 65% REO

Monticellite

CaMgSiO4

Orth

3.2

5

Rare olivine

Montmorillonite

(Al,Mg)8(Si4O10)3(OH)10. 12H2O

Mon

2.5

1-1½

Clay mineral

Montmorillonite Group . .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Family of clay minerals with 39.5% Al2O3, see Beidellite, Hectorite, Montmorillonite, Nontronite and Saponite

Moonstone

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Opalescent albite or orthoclase

Morganite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Rose beryl

Mullite

Al6Si2O13

Orth

3.23

6-7

Formed by heating andalusite kyanite or sillimanite

Muscovite

KAl2(AlSi3O16)(OH)2

Mon N

2.76-3.1

2-2½

Common clear mica

Nacrite

Al2(Si2O5)(OH)4

Mon

2.6

2-2½

Kaolin group clay mineral

Nagyagite

Pb5Au(Te,Sb)4S5-8

Mon

7.4

1-1½

Rare

Natroalunite

. .

Natrolite

Na2(Al2Si3O10).2H2O

Mon

2.25

5-5½

A zeolite

Nepheline

(Na,K)AlSiO4

Hex

2.55-2.65

5½-6

A feldspathoid. 22% Na2O, 36% Al2O3

Nephrite

. .

Niccolite

NiAs

Nickel bloom

. .

Nickel iron

Ni,Fe

Iso

7.8-8.2

5

In meteorites, 5-15% Ni

Nickel skutterudite

(Ni,Co,Fe)As3

Iso

6.1-6.9

5½-6

2-6% Co, 12-20% Ni, 73-78% As

30

. .

. . . .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Hex . .

. .

. .

. .

. .

. .

. .

. .

. .

. .

7.78 . .

. .

. .

. . 5-5½

. .

. .

Alunite with Na>K

Jade-like var. of tremolite Copper-red. 43.9 % Ni Annabergite

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

Name

Composition

Xal.Sys.

D

H

Remarks

Orth Mon Orth Iso O

2.09-2.14 2.5 3.1-3.2 2.25-2.4

2 1-1½ 6 6

Saltpetre Montmorillonite group clay mineral Chondrodite group A feldspathoid

. . . . Tric

. . . . 2.65

Nitre Nontronite Norbergite Nosean (Noselite)

KNO3 Fe(AlSi)8O20(OH)4 Mg3(SiO4)(F,OH)2 Na8Al6Si6O24.(SO4)

Octahedrite Oligoclase Olivine Group

. . . . . . . . . . Ab90An10-Ab70An30 (Mg,Fe)2SiO4

Onyx Opal Orpiment Orthite Orthoclase Osmiridium Ottrelite

. . . . . . . . . . . . . . . . . . . . . . . . Amor 1.9-2.2 5-6 SiO2.nH2O Mon 3.49 1½-2 As2S3 . . . . . . . . . . . . . . . . . . . . . . . . Mon 2.57 6 K(AlSi3O8) . . . . . . . . . . . . . . . . . . . . . . . . 3.5 6-7 (Fe 2+,Mn)(Al,Fe3+)Si3O10.H2O Mon P

Palladium Paragonite Pargasite Patronite Peacock ore Pearceite Pectolite Penninite Pentlandite Periclase Peridot Perovskite Perthite

Pd Iso Mon NaAl2(AlSi3O10)(OH)2 Mon NaCa2Mg4Al3Si6O22(OH)2 Impure V sulphide . . . . . . . . . . . . . . . . . Mon (Ag,Cu)16As2S11 Tric NaCa2Si3O8(OH) . . . . . . . . . . . . . . . . . Iso (Fe,Ni)9S8 MgO Iso . . . . . . . . . . . . . . . . . Iso CaTiO3 . . . . . . . . . . . . . . . . .

Petalite Petzite Phenacite Phillipsite

Li(AlSi4O10) Ag3AuTe2 Be2SiO4 (K2,Na2,Ca)Al2Si4O12. 4.5 H2O K(Mg,Fe)3AlSi3O10(OH,F)2 Pb2Cl2CO3 Ca(UO2)4(PO4)2(OH)4.7H2O . . . . . . . . . . . . . . Mn2+ epidote (Ca,Mg,Fe)SiO3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . NaAlSi3O8 (albite-Ab100 An0) to CaAl2Si2O8 (anorthite-Ab0An100) Pb5Sb8S17 Pt alloy . . . . . . . . . . . . . .

Phlogopite Phosgenite Phosphuranylite Picotite Piedmontite Pigeonite Pinite Pitchblende Plagioclase Plagionite Platinum Pleonaste

Field Geologists’ Manual

. .

. .

. . 6

11.9 2.85 3-3.5 .

. . . . 6.15 2.7-2.8 . . . . . 4.6-5.3 3.6-3.9 . . . . . 4.03 . . . . .

Mon Iso? Rho Mon

4½-5 2 5½ . . 3 5 . . 3½-4 5.5-6 . . 5½ . .

2.4 8.7-9.0 2.97-3.00 2.2

6-6½ 2½-3 7½-8 4½-5

Mon 2.86 Tet 6.0-6.3 Tet . . . . . . . . . Mon 3.4 Mon 3.2-3.4 . . . . . . . . . . . . . . . . . . Tric 2.62-2.76

2½-3 3 2½ . 6½ 5-6 . . 6

Mon Iso . . . .

5.56 14-19 . . . .

2½ 4-4½ . .

Anatase A plagioclase feldspar (Forsterite-Fayalite series), also rarer members Larsenite, Monticellite, Tephroite. Layered chalcedony Conchoidal fracture Yellow. 61% As Allanite Common K feldspar Hex. iridosmine Mn chloritoid With platinum Na muscovite Greenish Na hornblende Vanadium ore (Peru) Bornite Var. of polybasite Crystals acicular Chlorite variety With pyrrhotite. 34-35% Ni Contact met. mineral Gem olivine 58% TiO2, variable REO Microcline and albite intergrowth A feldspathoid. 5% Li2O In pegmatites. 45.6% BeO Var. of stilbite Brown mica Easily fusible. 75% Pb Yellow secondary U mineral Cr spinel Reddish brown Pyroxene in basic volcanics Muscovite after other minerals Uraninite See Albite, Oligoclase, Andesine, Labradorite, Bytownite, Anorthite Jamesonite series Grains in placers Iron spinel

31

MINERAL AND ROCK INFORMATION

Name Plumbago Polianite Pollucite Polybasite Polycrase

Composition

Xal.Sys.

Polyhalite Potash alum Potassium feldspar Potash mica Powellite Prase Prehnite Prochlorite Proustite

Tric Iso . . . . . . . . Tet . . . . . . Orth . . . . . . Rho

2.78 1.75 . . . . . . . . . . . . 4.23 . . . . . . 2.8-2.95 . . . . . . 5.55

Psilomelane

. .

. .

. .

. .

. .

. .

. .

Purple copper ore Pyrargyrite

. . . . . . Ag3SbS3

. .

. .

. .

. .

Pyrite Pyrochlore

. .

. .

. .

. . . . Tet Iso Mon Orth

D

. . . . . . . . . . MnO2 (Cs,Na)2Al2Si4O12.H2O (Ag,Cu)16Sb2S11 AB2O6, A = Y, Ce, Ca, U,Th; B = Ti, Nb, Ta, Fe K2Ca2Mg(SO4)4.2H2O KAl(SO4)2.11H2O KAlSi3O8 . . . . . . . . . . CaMoO4 . . . . . . . . . . Ca2Al2(Si3O10)(OH)2 . . . . . . . . . . Ag3AsS3

. .

. . . . 5.0 2.9 6.0-6.2 4.7-5.9

. .

. .

H . . 6-6½ 6½ 2-3 5½-6 ½

. . . .

2½-3 2-2½ . . 3½-4 . 6-6½ . 2-2½

. .

. . . . Rho

. . . . 5.85

FeS2 (Na,Ca)2(Nb,Ta)2O6(OH,F)

Iso Iso

5.02 4.2-4.5

6-6½ 5

Pyrolusite Pyromorphite

MnO2 Pb5(PO4)3Cl

Tet Hex

4.75 6.5-7.1

1-2 3½-4

Pyrope Pyrophyllite Pyroxene Group

(Mg,Fe)3Al2(SiO4)3 AlSi2O5(OH) . . . . . . . . . .

Iso Mon . . . . . .

3.51 2.8-2.9 . . . .

Pyrrhotite (1) Pyrrhotite (2) Quartz

Fe7S8 Fe11S12 SiO2

Rammelsbergite Rasorite Realgar Red copper ore Red ochre Rhodochrosite Rhodolite Rhodonite Riebeckite

Orth? 7.1 5½-6 NiAs2 . . . . . . . . . . . . . . . . . . . . . . . . AsS Mon 3.48 1½-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rho 3.45-3.6 3½-4 MnCO3 ½ 3(Mg,Fe)O.Al2O3.3SiO2 Iso 3.84 7 Tric 3.58-3.70 5½-6 MnSiO3 Mon 3.44 4 Na2(Fe,Mg)5Si8O22(OH)2

Rock crystal Rock salt Roscoelite Rubellite

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mon 2.97 2½ K(V,Al,Mg)3Si3O10(OH)2 . . . . . . . . . . . . . . . . . . . . . . . .

32

. .

Mon Hex Rho R

4.58 4.65 2.65

. . 2½

7 1-2 . . 4 4 7

Remarks Graphite Crystalline pyrolusite Colourless > 42% Cs2O 74% Ag, 10% Sb, to 12% Cu 14-30% REO, max. 13% U3O8, max. 26% (Nb2O5+Ta2O5) Bitter taste. 15.6% K2O 6-10% K2O See Orthoclase, Microcline Muscovite Fluorescent. 48% Mo Dull green jasper Tabular crystals Chlorite variety Light ruby silver, red streak. 65.4% Ag, 15.2% As Field name for massive, hard manganese minerals. About 50% Mn Bornite Dark ruby silver, red streak. 22.3 % Sb, 59.9% Ag Crystals striated. 46.5% Fe Infusible. 3-6% REO, 56-73% Nb2O5 Sooty. 63.2% Mn Adamantine lustre. 49-76 % Pb, max. 8% As Dark red garnet Resembles talc See Aegerine, Augite, Diopside, Enstatite, Jadeite, Spodumene Magnetic, 59.5% Fe Nonmagnetic, 62% Fe 46.7% Si 28% Ni Kernite Red. 70% As Cuprite Hematite Pink. 49% Mn Pale red or purple garnet Pink. 42% Mn Amphibole, end member of glaucophane series Euhedral clear quartz Halite Vanadium mica Red or pink tourmaline

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

Name

Composition

Xal.Sys.

D

H

Remarks

Ruby

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Red gem corundum

Ruby copper

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Cuprite

Ruby silver

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Pyrargyrite or proustite

Rutile

TiO2

Saleeite

Mg(UO2)2(PO4)2.8H2O

Samarskite

(RE,U,Ca,Fe,Pb,Th)(Nb,Ta,Ti, Sn)2O6

Sanidine

. .

Saponite

(Mg,Al)6(Si,Al)8O20(OH)4

Sapphire

. .

. .

. .

. .

. .

. .

. .

Satin spar

. .

. .

. .

. .

. .

. .

. .

Scapolite

Marialite-meionite series

Tet

2.65-2.74

5-6

Metamorphic, fluorescent

Scheelite

CaWO4

Tet

5.9-6.1

4½-5

Fluorescent. 70-80% WO3

Schorlite

. .

Scolecite

Ca(Al2Si3O10)3H2O

Mon

2.16-2.4

5-5½

A zeolite Green to brown. About 32% As

Tet S

. .

. .

. .

. .

. .

. .

. .

. .

4.18-4.25

6-6½

Platy sec. U mineral, autunite series, fluorescent

. .

. .

. .

Orth . .

4.1-6.2 . .

Mon

. .

. .

. .

2.5

5-6 . . 1-1½

. .

. .

Blue gem corundum

. .

. .

. .

. .

. .

Fibrous gypsum

. .

. .

. .

. .

. .

FeAsO4.2H2O

Orth

3.1-3.3

3½-4

Mon

3.35

5½-6

Selenite

. .

. .

. .

. .

Montmorillonite group clay mineral

. .

(Fe,Mg)Al2(PO4)2(OH)2 . .

High temp. orthoclase

. .

Scorodite

. .

10-22% REO, 28-46% Nb2O5, 2-27% Ta2O5, 0-12% U3O8

. .

Scorzalite

. .

Adamantine lustre

. .

. .

. .

. .

. .

Common black tourmaline

End member of lazulite series Clear crystalline gypsum

Semseyite

Pb9Sb8S21

Mon

5.8

2½

Jamesonite series

Sepiolite

Mg4(Si2O5)3(OH)2.6H2O

Mon?

2.0

2-2½

Meerschaum, light, sec. With serpentine

Sericite

. .

Serpentine

(Mg,Fe)3Si2O5(OH)4

Mon

2.2

2-5

43% MgO

Siderite

FeCO3

Rho

3.83-3.88

3½-4

48.2% Fe

Siegenite

(Co,Ni)3S4

Iso

4.8

4½-5 ½

Linnaeite series. 29% Co, 29% Ni

Sillimanite

Al2SiO5

Orth

3.23

6-7

Cl (010) perfect. 63.2% Al2O3

Silver

Ag

Iso

10.5

2½-3

White, malleable

. .

. .

. .

. .

. .

. .

. .

. .

. .

?

64% U3O8

Skutterudite

(Co,Ni,Fe)As3

Iso

6.1-6.9

5

l1-21% Co, 73-79% As, 0-9% Ni

Smaltite

. .

Smithsonite

ZnCO3

Soapstone

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Rho . .

. .

4.35-4.40 . .

. .

Fine-grained muscovite

3.54

. .

. .

. .

Orth

. .

. .

. .

. .

. .

. .

. .

Mg(UO2)2Si2O7.6H2O . .

. .

. .

Sklodowskite

. .

. .

. .

Silver glance

. .

. .

. .

. . 5 . .

Argentite

Skutterudite variety. 13-24% Co, 63-71% As, 1-15% Ni 52% Zn Talc

Sodalite

Na4Al3Si3O12Cl

Iso

2.15-2.3

5½-6

A feldspathoid

Soda nitre

NaNO3

Rho

2.29

1-2

36.5% Na2O

Spathic iron

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Siderite

Specular iron

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Foliated hematite

Sperrylite

PtAs2

Iso

10.50

6-7

54% Pt

Spessartite

Mn3Al2(SiO4)3

Iso

4.18

7

Brown to red garnet

Sphalerite

(Zn,Fe)S

Iso

3.9-4.1

3½-4

38-67% Zn, max. 5% Cd Wedge-shaped xals. 40% TiO2

Sphene

CaTiO(SiO4)

Mon

3.40-3.55

5-5½

Spinel Group

(Mg,Fe,Zn,Mn)Al2O4

Iso

3.6-4.0

8

In octahedrons

Spodumene

LiAl(Si2O6)

Mon

3.15-3.20

6½-7

A pyroxene. 8% Li2O

Field Geologists’ Manual

33

MINERAL AND ROCK INFORMATION

Name Stannite

Composition

Xal.Sys.

Cu2FeSnS4

Tet

Staurolite

(Fe,Mg)2A2Si4O23(OH)

Steatite

. .

. .

. .

. .

. .

4.4

Orth . .

. .

. .

D 4

3.65-3.75 . .

. .

H

. .

7-7½ . .

Remarks Easily fusible. 29-31% Cu, 27% Sn, 12-14% Fe In cruciform twins. 56% Al2O3 Talc

Stephanite

Ag5SbS4

Orth

6.2-6.3

2-2½

68.5% Ag, 15.2% Sb

Sternbergite

AgFe2S3

Orth

4.1-4.2

1-1½

34% Ag, 35% Fe

Stibnite

Sb2S3

Orth

4.52-4.62

2

71.7% Sb

Stilbite

NaCa2Al5Si3O36.14H2O

Mon

2.1-2.2

3½-4

A zeolite

Stillwellite

(Ce,La,Ca)BSiO5

Rho

4.57

Stolzite

PbWO4

Tet

8.3-8.4

2½-3

45% Pb, 50% WO3

Stromeyerite

(Cu,Ag)S

Orth

6.2-6.3

2½-3

53% Ag, 31% Cu

Strontianite

SrCO3

Orth

3.7

3½-4

Efferv. in HCl. 90% SrO

Struverite

. .

Sulphur

S

Sunstone

. .

Sylvanite

(Au,Ag)Te2

Mon

8.0-8.2

1½-2

Cl (010) perfect. 25% Au, 15% Ag

Sylvite

KCl

Iso

1.99

2

Cl cubic perfect. 63% K2O

. .

. .

. .

. .

. .

. .

. .

. .

Orth . .

. .

. .

. .

. .

. .

. .

. .

58% REO, 11% B2O3

. .

2.05-2.09 . .

. .

. .

. . 1½-2½ . .

Ta rich ilmenorutile Burns with blue flame Brilliant translucent oligoclase

T Talc

Mg3(Si4O10)(OH)2

Mon

2.7-2.8

1

Greasy feel

Tantalite

(Fe,Mn)(Ta,Nb)2O6; with Ta>Nb

Orth

6.2-8.0

6-6½

52-86% Ta2O5, max. 31% Nb2O5 (with Ta = Nb)

Tapiolite

(Fe,Mn)(Ta,Nb)2O6

Tet

7.3-7.8

6

Dimorphous with tantalite

Tennantite

(Cu,Fe,Zn,Ag)12As4S13

Iso

4.6-5.1

3-4½

Max. 11% Fe, 9% Zn, 14% Ag, 4% Pb, 13% Bi, 1% Co, 30-53% Cu

Tenorite

CuO

Tric

5.8-6.4

3-4

Black. 79.9% Cu

Tephorite

Mn2(SiO4)

Orth

4.1

6

Rare olivine

Tetrahedrite

(Cu,Fe,Zn,Ag)12Sb4Sl3

Iso

4.6-5.1

3-4½

In tetrahedrons. Max. 45% Cu, 13% Fe, 8% Zn, 18% Ag, 17% Hg, 16% Pb, 4% Ni, 4% Co, 4% Bi

Thenardite

Na2SO4

Orth

2.68

2½

In saline lakes

Thomsonite

NaCa2Al5Si5O20.6H2O

Orth

2.3

5

A zeolite To 17% U3O8

Thorianite

ThO2

Iso

9.7

6½

Thorite

Th(SiO4)

Tet

5.3

5

Thulite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Pink-red zoisite

Tiger's-eye

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Yellow brown quartz after crocidolite

Tin

Sn

Tinstone

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Cassiterite

Titanic iron ore

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Ilmenite

Titanite

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Sphene

Topaz

Al2(SiO4)(F,OH)2

Orth

3.4-3.6

8

Cl (001) perfect

Torbernite

Cu(UO2)2(PO4)2.8-12H2O

Tet

3.22

2-2½

Green. 61% U3O8, 13.5-15% P2O5, 6-7% Cu

Tourmaline

XY3Al6(BO3)3(Si6O18)(OH)4 X = Na, Ca; Y = Al, Fe, Li, Mg

Rho

3.0-3.25

7-7½

Trigonal section

Tremolite

Ca2Mg5(Si8O22)(OH)2

Mon

3.0-3.3

5-6

Ca amphibole, short fibre asbestos

34

Tet

7.3

2

Usually hydrated

Very rare

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

Name Tridymite Triphylite Troilite Trona Troostite Tungstite Turgite Turquoise

Composition Xal.Sys. Orth SiO2 Li(Fe,Mn)PO4 Orth . . . . . . . . . . . . . . . . . . Na2CO3.NaHCO3.2H2O Mon . . . . . . . . . . . . . . . . . . WO3.nH2O Orth? 2Fe2O3.nH2O ? CuAl6(PO4)4(OH)8.5H2O Tric

D 2.26 3.42-3.56 . . . . . 2.13 . . . . . ? 4.2-4.6 2.6-2.8

H 7 4½-5 . 3 . 2½ 6½ 6

Tyuyamunite

Ca(UO2)2(VO4)2.5-8H2O

3.7-4.3

2

Orth

Vanadinite Variscite Verde antique

U NaCaB5O9.8H2O Tric 1.69 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UO2 to UO3 Iso 9.0-9.7 Ca(UO2)2Si2O7.6H2O Orth 3.81-3.90 Bi2O3.2UO3.3H2O Orth 6.36 Ca3Cr2(SiO4)3 Iso 3.45 V Pb5(VO4)3Cl Hex 6.7-7.1 Al(PO4).2H2O Orth 2.4-2.6 . . . . . . . . . . . . . . . . . . . . . . .

Vermiculite Vesuvianite Violarite Vivianite

. . . . . . . . . . . . . . . . Ni2Fe S4 Fe3(PO4)2.8H2O

Wad Wavellite Wernerite White iron pyrites White mica Willemite Witherite Wolframite Wollastonite Wood tin Wulfenite Wurtzite

Hyd. Mn oxides Al3(OH)3(PO4)2.5H2O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Zn2SiO4 BaCO3 (Fe,Mn)WO4 Ca(SiO3) . . . . . . . . . . PbMoO4 (Zn,Fe)S

Xenotime

YPO4

Yellow copper ore

. .

. .

. .

. .

. .

. .

. .

Zeolite Group

. .

. .

. .

. .

. .

. .

. .

Zinc blende Zincite

. . . . ZnO

. .

. .

. .

. .

. .

Ulexite Uralian emerald Uralite Uraninite Uranophane Uranosphaerite Uvarovite

Field Geologists’ Manual

. . . .

. . . .

. .

. . . . . . . . . . . .

. .

. .

Mon . . . . Iso Mon W Orth . . . . . . Rho Orth Mon Tric . . Tet Hex X Tet Y . . Z . .

2.4 . . . . . 4.8 2.58-2.68

1 . . 5½ 2-3 2-3 7½

7.7% Na2O, 43% B2O3 Green gem andradite Hornblende after pyroxene Pitchy lustre, nom. U3O8 63% U3O8 61% U3O8, 42% Bi2O3 Green garnet

3 3½-4½ .

19.4% V2O5, 68-73% Pb Green, massive. 43-45% P2O5 Variegated serpentine and white marble Altered biotite Idocrase 34-43% Ni, 15-18% Fe Cl (010) perfect. 28% P2O5

1½ . 4½-5½ 1½-2

2.33 3½-4 . . . . . . . . . . . . . . . . . . . . . . . . 3.9-4.2 5½ 4.3 3½ 7.0-7.5 5-5½ 2.8-2.9 5-5½ . . . . . . . . 6.5-7.5 3 4.0 4 4.4-5.1

Remarks In volcanic rocks (870-1470°C) 9.5% Li2O, 45% P2O5 Pyrrhotite Alkaline taste. 41% Na2O Manganiferous willemite Sec. mineral With goethite Blue-green. 5.5-7.8% Cu, 28-35% P2O5 Ca analogue of carnotite. About 56% U3O8, 20% V2O5

4-5

25-48% Mn 35% P2O5, 38% Al2O3 Scapolite Marcasite Muscovite Fluorescent, 58.5% Zn Efferv. in HCl. 77.7% BaO About 75% WO3 Cl (001), (100) Cassiterite Orange-red. 56% Pb, 26.6% Mo Max. 67% Zn, 8% Fe, 3.6% Cd 61.4% REO, 38.6% P2O5

. .

. .

. .

. .

Chalcopyrite

. .

. .

. .

. .

See Analcime, Chabazite, Heulandite, Natrolite, Stilbite. Sphalerite 80% Zn, orange-yellow streak

. . . . Hex

. . . . 5.68

. . 4-4½

35

MINERAL AND ROCK INFORMATION

Name Zinc spinel Zinkenite Zinnwaldite Zircon Zoisite

Composition . . . . . . . . . . Pb6Sb14S27 Fe, Li mica ZrSiO4 Ca2Al3Si3O12(OH)

Xal.Sys. . .

. .

. . . . Hex Mon Tet Orth

Reproduced by permission from: Gary, M, McAfee, R Jr, and Wolf, C L, 1972. Glossary of Geology (American Gelogical Institute: Washington, D C).

36

D . . . . 5.3 3 4.68 3.3

H . . 3-3½ 2.5-3 7½ 6

Remarks Gahnite Jamesonite series About 5% Li2O 67.2% ZrO2 Orth var. of clinozoisite

Hurlburt, C S, 1961. Dana's Manual of Mineralogy (Wiley: New York). Palache, C, Berman, H, and Frondel, C, 1944. Dana's System of Mineralogy, Vol 1, 7th ed II, 7th ed (Wiley: New York).

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

2.2.1. LIST OF COMMON MINERALS IN ORDER OF DENSITY Density 0.4-0.6 (2.2) 1.6 1.7 1.75 1.85-1.89 1.90 1.9-2.2 1.95 1.96 1.98 1.99 2.0 2.0-2.2 2.04-2.17 2-2.4 2.05-2.09 2.05-2.15 2.09-2.14 2.1 2.1-2.2 2.12-2.30 2.13 2.15-2.30 2.16 2.16-2.4 2.18-2.20 2.2

2.2-2.8 2.25 2.26 2.27 2.28 2.29 2.30 2.3

2.3-2.4 2.32 2.33 2.39 2.4

Mineral Name Diatomite Carnallite Borax Epsomite, Potash Alum Allophane Melanterite Opal Kernite Ulexite Goslarite Sylvite, Gaylussite Sepiolite Halloysite Gmelinite Chrysocolla Sulphur Chabazite Nitre Kainite Stilbite Chalcanthite Trona Sodalite Halite Scolecite Heulandite Lechatelierite, Phillipsite, Serpentine Garnierite Natrolite Tridymite Analcime Laumontite Soda Nitre Cristobalite Graphite, Glauconite, Thomsonite Gibbsite, Apophyllite Gypsum Wavellite Brucite Petalite, Vermiculite

Field Geologists’ Manual

Density 2.4-2.45 2.4-2.5 2.4-2.6 2.42 2.45 2.45-2.50 2.5

2.54-2.57 2.55-2.65 2.57 2.58 2.58-2.68 2.6 2.6-2.63 2.6-2.64 2.6-2.65 2.6-2.66 2.6-2.8 2.6-2.9 2.61 2.62 2.62-2.76 2.65 2.65-2.74 2.67 2.68 2.69 2.7 2.7-2.8 2.7-2.85 2.71 2.72 2.74 2.75-2.80 2.76 2.76-3.1 2.78 2.8 2.8-2.9 2.8-2.95

Mineral Name Lazurite Hauynite Variscite Colemanite Cancrinite, Harmotome Leucite Bentonite, Hectorite, Montmorillonite, Nontronite, Saponite Microcline Nepheline Orthoclase Anorthoclase Vivianite Nacrite Anauxite, Dickite, Beidellite Chalcedony Kaolinite Cordierite Turquoise, Alunite Penninite, Chlorite, Clinochlore Kaliophilite Albite Plagioclase Quartz, Flint, Oligoclase, Chert Scapolite Eucryptite Thenardite Andesine Marialite, Meionite Pectolite, Talc Glauberite Labradorite Calcite Bytownite Beryl Anorthite Muscovite Polyhalite Hyalophane Pyrophyllite, Wollastonite Prehnite

Density 2.8-3.0 2.8-3.2 2.83 2.85 2.85-3.2 2.85-3.45 2.86 2.89-2.98 2.9 2.9-3.0 2.9-3.1 2.9-4.3 2.91-3.26 2.95 2.95-3.0 2.97 2.97-3.0 2.97-3.02 3.0

3.0-3.1

3.01-3.06 3.0-3.2

3.0-3.25 3.0-3.3 3-3.5 3.09 3.1 3.1-3.2

3.1-3.3 3.1-3.6 3.15-3.20 3.16-3.20 3.16-3.36 3.18 3.19 3.2

Mineral Name Datolite, Lepidolite Biotite Langbeinite Dolomite, Paragonite Anthophyllite Amphibole Phlogopite Anhydrite Pollucite Boracite Melilite Asbolite Jarosite Aragonite, Erythrite Ankerite, Cryolite Roscoelite Phenacite Danburite Annabergite, Edenite, Ferrimolybdite, Zinnwaldite Amblygonite, Lazulite, Margarite Boehmite Actinolite, Glaucophane, Magnesite Tourmaline Tremolite Pargasite Lawsonite Euclase Autunite, Chondrodite, Clinohumite, Humite, Norbergite Scorodite, Bronzite Cummingtonite Apatite, Spodumene Andalusite Helvite Fluorite Clinoenstatite Hornblende, Monticellite, Forsterite, Hastingsite

37

MINERAL AND ROCK INFORMATION

Density 3.2-3.3 3.2-3.4 3.2-3.5 3.2-3.7 3.22 3.23 3.25-3.37 3.26-3.36 3.27-3.35 3.27-4.37 3.3 3.33-3.5 3.35 3.35-3.45 3.37 3.4 3.4-3.5 3.40-3.55 3.4-3.6 3.42-3.56 3.44 3.45 3.45-3.60 3.48 3.49 3.5 3.51 3.5-3.8 3.5-4.2 3.5-4.3 3.53 3.54 3.55 3.56-3.66 3.58-3.70 3.6 3.6-3.8 3.6-4.0 3.65-3.75 3.65-3.8 3.7 3.7-4.3 3.7-4.7

38

Mineral Name Crocidolite, Diopside Augite, Pigeonite Enstatite Aurichalcite Torbernite Sillimanite, Mullite Clinozoisite Dumortierite Axinite Olivine Dioptase, Zoisite Jadeite Scorzalite Diaspore, Epidote, Idocrase Celsian Piedmontite Hemimorphite, Hypersthene Acmite, Aegerine, Sphene Topaz Triphylite Riebeckite Arfvedsonite, Uvarovite Rhodochrosite Realgar Orpiment Chloritoid, Diamond, Ottrelite, Lithiophilite Pyrope Iddingsite Allanite Garnet Grossularite Sklodowskite Hedenbergite Kyanite Rhodonite Clinoferrosilite, Ferrosilite Hydrozincite Limonite, Spinel Staurolite Chrysoberyl Pyroxene, Strontianite Tyuyamunite Psilomelane

Density 3.75 3.75-3.77 3.77 3.81-3.90 3.83-3.88 3.84 3.90 3.9 3.9 3.9-4.0 3.9-4.03 3.9-4.1 3.9-4.2 3.9-6.4 3.95-3.97 4.0 4.0-4.5 4-5 4.02 4.03 4.03-4.18 4.09 4.1 4.1-4.2 4.1-4.3 4.1-6.2 4.14 4.18 4.18-4.25 4.2 4.2-4.5 4.2-4.6 4.2-5.8 4.23 4.25 4.3 4.3-4.6 4.35-4.40 4.37 4.38 4.39 4.4 4.4-5.1 4.43-4.45 4.5 4.5-5.4 4.52-4.62

Mineral Name Andradite Atacamite Azurite Uranophane Siderite Rhodolite Brochantite Anterlite Anatase Marmatite Malachite Brookite, Sphalerite Willemite Gummite Celestite Alabandite, Ilvaite, Libethenite, Wurtzite Gadolinite Cervantite Corundum Perovskite, Galaxite Cubanite Lepidocrocite Carnotite, Tephroite Sternbergite Chalcopyrite Samarskite Fayalite Spessartite Rutile Magnesiochromite Pyrochlore Turgite Fergusonite Powellite Almandite Manganite, Witherite Chromite Smithsonite Goethite Clinoclase Hercynite Stannite Xenotime Enargite Barite, Magnesioferrite Brannerite Stibnite

Density 4.55 4.57 4.58-4.65 4.6-4.76 4.6-5.0 4.6-5.1 4.62-4.73 4.66 4.68 4.7 4.7-5.9 4.75 4.8 4.84 4.89 4.9 4.9-5.2 5.0 5.0-5.3 5.0-5.4 5.0-5.9 5.02 5.06-5.08 5.1 5.15 5.18 5.2-5.3 5.2-6.7 5.26 5.3 5.3-5.7 5.5-6 5.5-5.8 5.55 5.56 5.6 5.68 5.7 5.8-5.9 5.8-6.4 5.85 5.9 5.9-6.1 5.9-6.2 6.0

Mineral Name Gahnite Stillwellite Pyrrhotite Covellite Pentlandite Tennantite, Tetrahedrite Molybdenite Bravoite Zircon Ilmenite Polycrase Pyrolusite Braunite, Linnaeite, Siegenite, Violarite Hausmannite Marcasite Greenockite Bastnaesite Polianite Monazite Manganosite Euxenite Pyrite Bornite Jacobsite Franklinite Magnetite Miargyrite Columbite Hematite Thorite, Linarite, Zinkenite Millerite Cerargyrite, Jamesonite Chalcocite Proustite Plagionite Embolite, Digenite Zincite Arsenic, Iodobromite, Iodyrite Bournonite Tenorite Pyrargyrite Gersdorffite, Larsenite Crocoite, Scheelite Arsenopyrite, Danaite Cuprite

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

Density 6.0-6.2 6.0-6.3 6.0-6.5 6.1-6.9 6.1-7.7 6.15 6.2-6.3 6.2-6.4 6.2-8.0 6.3-6.5 6.33 6.36 6.5-7.1 6.5-7.5 6.55 6.7 6.7-7.1 6.75-6.81 6.8-7.1

Mineral Name Polybasite Phosgenite, Boulangerite Bromyrite Smaltite, Skutterudite Bismutite Pearceite Stephanite, Stromeyerite Anglesite Tantalite Geocronite Cobaltite, Microlite Uranosphaerite, Menaghinite Pyromorphite Wulfenite Cerussite Antimony Vanadinite Bismuthinite Cassiterite

Field Geologists’ Manual

Density 7.0 7.0-7.2 7.0-7.5 7.1 7.2 7.2-7.3 7.3

7.4 7.5-7.5 7.4-7.6 7.5 7.7-8.1 7.78 7.8-8.2 8.0 8.0-8.2 8.10 8.16

Mineral Name Huebnerite Mimetite Wolframite Rammelsbergite Calomel Acanthite Argentite, Manganotantalite, Tin metal Nagyagite Loellingite Galena Ferberite Awaruite Niccolite Nickel iron Bismite Sylvanite Cinnabar Altaite

Density 8.3-8.4 8.4 8.62 8.7-9.0 8.9 8.9-9.2 9-9.7 9.35 9.7 9.8 10.5 11.9 13.5-17.5 13.6 14-19 15.0-19.3 19.3-21.1 22.7

Mineral Name Stolzite Hessite Krennerite Petzite Copper Minium Uraninite Calaverite Thorianite Bismuth Silver, Sperrylite Palladium Electrum Mercury Platinum Gold Iridosmine Iridium

39

40

2.89 @ 20°C

acetone, alcohol, NN-dimethylformamide

CHBr3

ex lab. stock

water washing air sparging, distillation

low

high

heat, sulphur

no

Maximum specific gravity

Miscible with

Composition

Preparation

Concentrated by

Toxicity hazard by contact

Toxicity hazard by vapour inhalation

Decomposed by

Acts on filter paper

Disadvantages

Bromoform

Name

no

metals, calcium ions

very low

very low

evaporation

ex lab. stock

aq. soln of lithium heteropolytungstates

water

2.95 @ 25°C 3.6 @ 87°C

LST heavy liquid

more viscous than TBE and LST

no

metals, calcium ions

very low

very low

evaporation

simple

aq. soln of 3Na2WO4.9WO3.H2O

water

3.1 @ 25°C

Sodium polytungstate

1. Revised by Dr K Henley of AMDEL Ltd, Thebarton, SA.

more viscous than bromoform

no

heat

high

low

water washing, air sparging, distillation

ex lab. stock, available in bulk

CHBr2.CHBr2

acetone, alcohol, NN-dimethylformamide

2.96 @ 20°C

Tetrabromoethane (TBE) (acetylene tetrabromide)

1

2.2.2. DESCRIPTION OF HEAVY LIQUIDS

deteriorates with use

yes

rubber, metal

low

very corrosive

evaporation

reasonably simple

aq. soln of mercuric potassium iodide

water

3.19

Thoulet solution

MINERAL AND ROCK INFORMATION

Field Geologists’ Manual

Field Geologists’ Manual

3.32 @ 20°C

acetone, alcohol, NN-dimethylformamide

CH2I2

ex lab. stock

water washing, air sparging, distillation

moderate

moderate

heat, sulphur

no

Maximum specific gravity

Miscible with

Composition

Preparation

Concentrated by

Toxicity hazard by contact

Toxicity hazard by vapour inhalation

Decomposed by

Acts on filter paper

Disadvantages

Di-iodomethane (methylene iodide)

Name

oily, rarely available

no

carbonate, lead, zinc, iron

low

low

evaporation

complex

aq. soln of cadmium borotungstate

water

3.55

Klein solution

hygroscopic

yes

metals

low

high

evaporation

reasonably simple

aq. soln of barium mercuric iodide

water with difficulty

3.59

Rohrbach solution

toxicity

no

moderate

high

evaporation

simple

aq. soln of thallium formate and malonate

water

4.28 @ 20°C 4.76 @ 90°C

Clerici solution

MINERAL AND ROCK INFORMATION

41

MINERAL AND ROCK INFORMATION

2.3.1. CLASSIFICATION OF PLUTONIC ROCKS - I.U.G.S. FIELD SYSTEM Minerals and mineral groups Q quartz A alkali feldspars (orthoclase, microcline, perthite, anorthoclase, albite An00-06) P plagioclase An06-100, scapolite F feldspathoids or foids (leucite and pseudoleucite; nepheline, sodalite, nosean, hauynite, cancrinite, analcime, etc.) M mafic and related minerals (micas, amphiboles, pyroxenes, olivines, opaque minerals, accessories (zircon, apatite, titanite, etc), epidote, allanite, garnets, melilites, monticellite, primary carbonates, etc.) Q + A + F = 100, or A + P + F = 100 Q

0- 90 volume % mafic minerals

quartzolite

90

1

Rocks with M less than 90 per cent are classified primarily according to their light-coloured constituents; rocks with M = 90-100 according to their mafic minerals. Rocks with M less than 90 per cent are classified and named according to their positions in the QAPF double triangle, the light-coloured constituents being calculated to the sum 100 (ie Q + A + F = 100 or, A + P + F = l00) Succession of minerals in rock names The Subcommission recommends that the minerals in composite rock names be arranged in the order of increasing amounts; ie a more abundant mineral falls closer to the root name of the rock than a less abundant mineral. Example: hornblende-biotite granodiorite contains more biotite than hornblende.

quartzrich granitoids 60

alkaliafeldspar granite

granite

monzonite 35 65

foid sye

nite

foid monzogabbro An>50

60 Q:5-20 add prefix quartz F:0-10 add prefix foid-bearing

monzodiorite An>50 monzogabbro An<50

foid monzodiorite An<50

foid monzosyenite

foidolites

e

syenite 10

granodiorite

alit

10

ton

alkalaifeldspar syenite A

ROCKS WITH M < 90%

anorthosite diorite An<50 gabbro An>50

90

P

foid diorite An<50 foid gabbro An>50 An = % anorthosite in plagioclase

F

GABBROIC ROCKS

1.

42

From Anon., 1973. Classification and nomenclature recommended by the I.U.G.S Subcommission on the Systematics of Igneous Rocks, Geotimes, October 1973, pp 26-30, by permission.

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

2.3.2. CLASSIFICATION OF VOLCANIC ROCKS – I.U.G.S. SYSTEM

1.

1

From Steickeisen, A, 1979. Classification and nomenclature of volcanic rocks, lamprophyres, carbonatites, and melitic rocks: recommendations and suggestions of the I.U.G.S. Subcommission on the Systematics of Igneous Rocks, Geology, 7: 331-335, by permission.

2.3.3. BROAD CLASSIFICATION OF IGNEOUS ROCKS BY COLOUR AND 1 GRAIN SIZE I.U.G.S. ANON. (1973) % Dark Minerals 0-35 Leucocratic 35-65 Mesocratic 65-90 Melanocratic 90 + Ultramafic

1.

Average grain diameter: < 1 mm - fine grained l-5 mm - medium grained 5-30 mm - coarse grained > 30 mm - pegmatitic

From Anon, 1973. Classification and nomenclature recommended by the I.U.G.S. Subcommission on the Systematics of Igneous Rocks, Geotimes, October 1973, 26-30, by permission.

Field Geologists’ Manual

43

MINERAL AND ROCK INFORMATION

2.3.4. CLASSIFICATION OF PYROCLASTIC ROCKS - I.U.G.S. SYSTEM

1

TABLE 1 Granulometric classification of pyroclasts and of unimodal, well-sorted pyroclastic deposits. Clast size (mm)

Pyroclast

Pyroclastic deposit Mainly unconsolidated: tephra

Mainly consolidated: pyroclastic rock

Bomb, block

Agglomerate, bed of blocks or bomb, block tephra

Agglomerate, pyroclastic breccia

Lapillus

Layer, bed of lapilli or lapilli tephra

Lapilli tuff

Coarse ash grain

Coarse ash

Coarse (ash) tuff

Fine ash grain (dust grain)

Fine ash (dust)

Fine (ash) tuff (dust tuff)

64 mm 2 mm l/16 mm Fig 1- Subdivision of tuffs and ashes according to their composition.

TABLE 2 Terms for mixed pyroclastic-epiclastic rocks. Pyroclastic*

Tuffites (mixed pyroclastic-epiclastic)

Epiclastic (volcanic and/or nonvolcanic)

Av. clast size (mm)

Agglomerate, agglutinate pyroclastic breccia

Tuffaceous conglomerate, tuffaceous breccia

Conglomerate, breccia

64

Tuffaceous sandstone

Sandstone

2

Tuffaceous siltstone

Siltstone

l/16

Tuffaceous mudstone, shale

Mudstone, shale

l/256

Lapilli tuff

coarse

(Ash) tuff

fine

100

75

25

0% by volume

Pyroclasts Volcanic + nonvolcanic epiclasts ( + minor amounts of biogenic, chemical sedimentary and authigenic constituents) * Terms according to Table 1.

1.

44

From Schmid, R, 1981. Descriptive nomenclature and classification of pyroclastic deposits and fragments: recommendations of the I.U.G.S. Subcommission on the Systematics of Igneous Rocks, Geology, 9, January 1981, 4 l-43, by permission.

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MINERAL AND ROCK INFORMATION

2.3.5. DIAMOND INDICATOR MINERALS (DIMs) DIMs derive from upper mantle rocks, mostly peridotite or eclogite. They can be transported to the earth’s surface by intrusives (most commonly kimberlites and lamproites) originating in the upper mantle which may potentially carry diamonds. DIMs have characteristic major element compositions. Trace elements in DIMs are also playing an increasing role in diamond exploration, particularly in garnets and Mineral and typical composition Pyrope garnet: (a) Peridotitic: a. Dunitic b. Harzburgitic c. Lherzolitic d. Wehrlitic (b) Eclogitic (c) Megacrystic see Cr2O3-CaO plot (Figure 1) for compositional ranges.

Chromian spinel (‘chromite’) (a) Low TiO2 (< 1 wt%) chromite DIMs are typified by high MgO (6-18 wt%) with variable Cr2O3 (25-70 wt%) but displaying a negative MgO-Cr2O3 relationship if TiO2 is less than 1 wt%, the so-called ‘mantle trend’ spinels, (Figure 2a). (b)

High TiO2 (approximately 1-5 wt%) chromite with high MgO (6 18 wt%) and high Cr2O3 (>40 wt% and often >55 wt%) are distinctive of kimberlites and lamproites (Figure 2b).

1

chromian spinels (see Griffin and Ryan, 1995). Diamond host rocks often do not carry a full suite of DIMs (eg garnet and ilmenite are rare in lamproite and some kimberlites). 1.

Information supplied by Bruce Wyatt of De Beers Australia Exploration Limited and Geof Fethers of Flagstaff GeoConsultants, Melbourne. Comment

Peridotitic lherzolitic garnets, together with eclogitic garnets, are the most common type of pyrope garnet in kimberlites and lamproites. Lherzolitic garnets are characterised mostly by 18-20 wt% MgO, 6-9 wt% FeO, 1-12 wt% Cr2O3, 4-7 wt% CaO and 0-2.0 wt% TiO2. Eclogitic garnets have lower MgO (4-16 wt%), variable but higher FeO (up to ~22 wt%) and CaO (up to ~25 wt%) than peridotitic garnets, and typically low Cr2O3 (0-0.5 wt%). Megacrystic garnets are large pyropes (~1+ cm) with variable composition, typified by high TiO2 (often >1 wt%). Subcalcic peridotitic garnets, which are similar to garnets found as diamond inclusions, seldom have more than 3 wt% CaO with Cr2O3 generally 5-14 wt% and low TiO2, mostly less than 0.2 wt%. These subcalcic peridotitic garnets are similar to those defined by Fipke, Gurney and Moore for their ‘G10’ garnets (see Gurney, 1984; Fipke et al., 1995) - a classification based on Dawson and Stephens (1975) for their Group 10 garnets. Since subcalcic peridotitic garnets can (but not exclusively) form under the same pressure and temperature conditions as diamond, they suggest that the transporting rocks may be diamond bearing if the upper mantle source was carbon rich. Chromites found in kimberlites and lamproites can be difficult to distinguish from common chromites. ‘Low TiO2 chromites’ are common in mafic and ultra-mafic rocks including both kimberlites and lamproites. ‘Low TiO2 chromites’ with 12-16 wt% MgO and 63-69 wt% Cr2O3 are similar, but not exclusive, to chromites included in diamond. The ‘low TiO2- high Cr2O3 chromites’ which fall in the diamond inclusion field (Figure 1), if known to be derived from a kimberlite or lamproite, may have formed under the same pressure and temperature conditions under which diamond forms. Their presence is an indication that the transporting kimberlite and lamproite may be diamond bearing if the upper mantle source was carbon rich. ‘High TiO2 chromite’ often occurs as rims to ‘Low TiO2 chromite’ cores and less commonly as whole grains. ‘High TiO2 chromite’ is brittle and seldom found more than 1 - 2 km (often much less) distance from the rock from which it was liberated in an abrading environment.

Picroilmenite - high Mg ilmenite Not always present in kimberlite and rarely present in lamproite, megacrystic (>0.5 wt%) ilmenite with high MgO (> 8 wt%) and high Cr2O3 (>0.5 wt%) remains one of a. High Cr2O3 megacrystic ilmenite with high the most diagnostic indicators of kimberlite (but not diamond prospectivity). Low Cr2O3 megacrystic picroilmenite is likely to derive from kimberlite unless MgO (generally 5-16 wt%). high MnO (>1 wt%) indicates a possible carbonatite or skarn source. b. Low Cr2O3 (< 0.15 wt% Cr2O3) megacrystic ilmenite with high MgO (9-12 wt%), high Al2O3 (>0.5% wt%). Chromian diopside High Cr2O3 contents (often 1-3+ wt%)

Distinctive apple green colour. Fragile, seldom found more than 5 km (often less than 2 km) from the rock from which it was liberated in an abrading environment.

Zircon Low U

When zircon is found in kimberlites and lamproites, it often has less than 50 ppm U.

Olivine High MgO

Olivine, although present in virtually all primary diamond source rocks, is susceptible to chemical weathering and in Australia is rarely recovered during exploration. Olivine from potential diamond host rocks is usually rich in MgO having a forsterite content of about 90% or higher.

Phlogopite

Field Geologists’ Manual

45

46

Dawson, J B & Stephens, W E, 1975, Statistical classification of garnets from kimberlites and associated xenoliths, J. Geol., 83, 589-607. Fipke C E, Gurney J J & Moore R O, 1995. Diamond exploration techniques emphasising indicator mineral geochemistry and Canadian examples, Geol. Surv. Canada. Bull. 423. Griffin W L, Gurney J J & Ryan C G, 1992. Variations in trapping temperatures and trace elements in peridotitic-suite inclusions from African diamonds: evidence for two inclusions suites, and implications for lithosphere stratigraphy, Contrib. Mineral. Petrol., 110, -15. Griffin, W L & Ryan, C G, 1995. Trace elements in indicator minerals: area selection and target evaluation in diamond exploration, J. Geochem. Explor. 53, p 311-337. Gurney J J, 1984. A correlation between garnets and diamonds in kimberlites, in Kimberlite Occurrence and Origin: A Basis for Conceptual Models in Exploration (Eds: Glover, J E & Harris, P G,) Geol. Dept. And Univ. Extension, The University of Western Australia, Publication 8, 143-166. Sobolev N V, Lavrent’Yev YU G, Pokhilenko N P & Usova L V, 1973. Chrome-rich garnets from the kimberlites of Yakutia and their parageneses. Dok. Akad. Nauk, SSSR, 249, 1271-1220.

REFERENCES

FIG 1 - Cr2O3-CaO plot showing typical compositional fields for a variety of perdotitic garnets typically found in kimberlites and lamproites. Data from the Brockman Creek kimberlite, Pilbara Craton, Australia are given as an example. Symbols show rock type after Gurney (1984) and Griffin et al. (1992). Lherz = Lherzolite, harz = Harzburgite. Solid line is lherzolite field after Sobolev et al. (1973). Note that eclogitic garnets would plot in a low Cr2O3 band along the CaO axis. (Brockman is weakly diamondiferous).

MINERAL AND ROCK INFORMATION

Field Geologists’ Manual

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FIG 2 - (a) MgO plot showing approximate upper mantle field for chromian spinels (‘chromites’) associated with kimberlites and lamproites. Tie-lines show core-rim associations. Non-kimberlitic spinels often display negative MgO-Cr2O3 trends at right angles to the mantle trends, but can overlap extensively with upper mantle spinels. (b) TiO2-Cr2O3 plot showing the ‘elbow’ shaped pattern for high-TiO2 chromian spinels found in kimberlites and lamproites. Note that rim compositions usually have the higher TiO2 content. An example from the Timber Creek 04 kimberlite, NT, Australia is given. (Timber Creek 04 has a possible diamond grade of 100 ct/100t).

Generalised trend for mantle-derived spinels

Generalised trend for high-TiO2 spinels

MINERAL AND ROCK INFORMATION

47

MINERAL AND ROCK INFORMATION

2.4.1. METAMORPHIC FACIES DIAGRAM

1.

48

1

From Turner, F J, 1981. Metamorphic Petrology (McGraw Hill: New York), by permission.

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

2.4.2. SUMMARY OF METAMORPHIC ROCKS

Field Geologists’ Manual

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MINERAL AND ROCK INFORMATION

50

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MINERAL AND ROCK INFORMATION

2.5.1. CLASSIFICATION OF ARENITES AND TERRIGENOUS SEDIMENTS

1

DEPOSITIONAL ENVIRONMENT UNKNOWN

DEPOSITIONAL ENVIRONMENT KNOWN FROM SEDIMENTARY STRUCTURES

MLQ diagrams for arenites on Packham’s classification (1954).

1.

From:

Crook, K A W, 1960. Classification of arenites, Am. Jour. Sci., 258: 419-428. Packham, G H, 1954. Sedimentary structures as an important feature in the classification of sandstones, Am. Jour. Sci., 252: 466-476, by permission.

Field Geologists’ Manual

See also: Blatt, H, Middleton, G, Murray, R, 1972. Origin of Sedimentary Rocks. (Prentice-Hall: New Jersey), for a range of arenite classifications.

51

MINERAL AND ROCK INFORMATION

1

CLASSIFICATION OF TERRIGENOUS SEDIMENTS

1.

From Pettijohn, F J, Potter, P E and Siever, R, 1972. Sand and Sandstones (Springer-Verlag: New York), p 158, by permission.

2.5.2. CLASSIFICATION OF CARBONATE SEDIMENTS 1. COMPOSITIONAL TERMINOLOGY

1.

From:

Leighton, M W, and Pendexter, C, 1962. Carbonate rock types, in Classification of Carbonate Rocks – a Symposium, Memoir 1 (Ed. W E Ham), p 51 (Amer. Assoc. Petrol. Geol.: Tulsa Oklahoma).

52

1

See also: Prothero, D R and Schwab, F, 1996. Sedimentary Geology (Freeman: New York), pp 237-245, for a more detailed classification of carbonate sediments.

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

2. CLASSIFICATION BY TEXTURAL MATURITY1 Over 2/3 lime mud matrix Per cent allochems

0-1%

1-10%

10-50%

Representative Micrite and Fossiliferous Sparse rock terms Dismicrite micrite Biomicrite

over 50% Packed Biomicrite

Allochems = organised carbonate aggregates, comprising intraclasts; oolites, pisolites and spherulites; fossils; and pellets. Micrite = microcrystalline calcite; Sparite = sparry calcite + 4 microns dia. Qualifying adjectives describing colour, hardness, bedding, sedimentary structures, etc, should be added.

1.

Subequal spar and lime mud Poorly washed Biosparite

Over 2/3 spar cement Sorting poor Sorting good Rounded and abraded Unsorted Biosparite

Sorted Biosparite

Rounded Biosparite

From Folk, R L, 1962. Spectral subdivision of limestone types, in Classification of Carbonate Rocks – a Symposium, Memoir 1 (Ed. W E Ham), pp 62-84, (Amer. Assoc. Petrol. Geol.: Tulsa, Oklahoma).

3. CLASSIFICATION ACCORDING TO DEPOSITIONAL TEXTURE1 DEPOSITIONAL TEXTURE RECOGNIZABLE Original components not bound together during deposition Contains mud Lacks mud (particles of clay and fine silt size) and is grain-supported Mud-supported Grain supported Less than 10 per More than 10 per cent grains cent grains Mudstone 1.

Wackestone

Packstone

Grainstone

Original components were bound together during deposition...as shown by intergrown skeletal matter, lamination contrary to gravity, or sediment-floored cavities that are roofed over by organic or questionably organic matter and are too large to be interstices.

DEPOSITIONAL TEXTURE NOT RECOGNIZABLE Crystalline Carbonate (Subdivide according to classifications designed to bear on physical texture or diagenesis)

Boundstone

From Dunham, R J, 1962. Classification of carbonate rocks according to depositional texture, in Classification of Carbonate Rocks (Ed: W E Ham), A. A. P. G. Mem. 1, pp 108-122, by permission.

2.5.3 ROUNDNESS AND SPHERICITY, RELATIVE RESISTANCE TO ABRASIVE ROUNDING, AND PARTICLE SIZE TERMINOLOGY FOR SEDIMENTARY AND PYROCLASTIC PARTICLES 1. ROUNDNESS AND SPHERICITY

Field Geologists’ Manual

53

MINERAL AND ROCK INFORMATION

2. RELATIVE RESISTANCE TO ABRASIVE ROUNDING Quartz (most resistant), tourmaline, microcline, staurolite, titanite, magnetite, garnet, ilmenite, epidote, zircon, hornblende, rutile, diallage, hypersthene, spodumene, apatite, monazite, augite, hematite, bronzite, kyanite, enstatite, fluorite, siderite, barite (least resistant).

3. PARTICLE SIZE TERMINOLOGY1

½

¼

¼8

¼16

¼32 ¼64 ¼128 ¼256

1.

54

From Pettijohn, F J, Potter, P E, and Siever, R, 1972. Sand and Sandstone (Springer-Verlag: New York), p 71, by permission.

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

2.5.4. BEDDING THICKNESS TERMINOLOGY Average thickness of beds or splits (mm) Bedding term

Splitting term

Very thinly laminated Laminated Very thinly bedded Thinly bedded Medium bedded Thickly bedded Very thickly bedded

Fissile Fissile Flaggy Flaggy Slabby Blocky Massive

From: 1.

2.

Anon., 1971. Report of subcommittee on sedimentary terminology, Rec. Geol. Surv. NSW, 13(2); 109-l14.

Anon.1

Payne2

10 10-30 30-100 100-300 300-1000 1000

2 2-10 10-100

> 100

Payne, T G, 1942. Stratigraphic analysis and environmental reconstruction, Amer. Assoc. Petrol. Geol. Bull. 26: 1697-1770, by permission.

2.5.5. A GENETIC CLASSIFICATION OF SEDIMENTARY STRUCTURES PRIMARY INORGANIC CURRENT FORMED DEPOSITIONAL EROSIONAL stratification channels & rills ripplemarks & cross laminations flute marks flaser & lenticular bedding scour scoops cross bedding (tabular & trough) stratification graded bedding current lineations (clast imbrication) SECONDARY INORGANIC-MECHANICAL QUASI-LIQUID QUASI-SOLID (thixotropic response) impact marks (eg raindrop imprints) fluidisation gas pits (complex distortion to homogenisation) (may resemble raindrop imprints) intrusions (dykes and sills) ice crystals extrusions (volcanoes) faults dewatering structures pull aparts (eg dish & flame structures) dessication

BIOSTRATIFICATION Stromatolites, biogenic graded bedding, others.

SECONDARY INORGANIC -CHEMICAL enterolithic folds (due to expansion) concretions (due to differential cementation) leisegang bands (iron oxide concentrations) stylolites (due to differential solution) crystallisation structures (salt or ice crystals, nodule growths) BIOGENIC STRUCTURES BORINGS mechanical and/or chemical excavations into solid substrates

1

TOOL MARKS grooves & striations roll & slide marks bounce, brush & prod marks

HYDROPLASTIC slump structures convolute lamination load structures founder structures (eg dish & flame structures) folds boudinage differential compaction folds

COPROLITES preserved fecal ejecta of invertebrates & vertebrates

BIOTURBATION TRACES RESTING

CRAWLING

GRAZING

FEEDING

DWELLING

ESCAPE

Lebensspuren (individually distinctive traces).

1.

From Lewis, D W, 1984. Practical Sedimentology (Hutchinson Ross: Stroudsburg, Pa), by permission.

Field Geologists’ Manual

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MINERAL AND ROCK INFORMATION

2.6. DIAGRAMS REPRESENTING VARIOUS PERCENTAGES OF GRAINS

1.

56

1

From Terry, R D and Chilingar, G V, 1955. Summary of ‘Concerning some additional aids in studying sedimentary formations’, by M S Shvetsov, J. sedim. Petrol. (25)3: 229-234, by permission.

Field Geologists’ Manual

MINERAL AND ROCK INFORMATION

2.7. REGOLITH TERMINOLOGY Regolith is the weathered and transported earth material that covers fresh rock. It includes in situ weathered rock and sediments transported by various means (eg colluvium, alluvium, aeolian materials, lacustrine deposits, till). In places the regolith may contain cemented materials that form duricrusts (silcrete, ferricrete, managanocrete, calcrete, dolocrete). Most regolith materials have a spatial relationship with the landscape. Hard rocks and regolith materials maintain hills, and softer materials form valleys. In many places the presence of a duricrust protects hills from erosion, so duricrusts commonly occur high in a landscape - although they are the result of cementing processes, and the fluids that carry the cement must move downslope and precipitate in lower parts of the landscape. Hence many duricrusts indicate topographic inversion, ie what were valleys are now hills. In other cases duricrusts (particularly ferricrete and bauxite) are thought to form by relative accumulation, by removal during weathering of all components less soluble than ferric oxides-oxyhydroxides and alumina. Depositional parts of the regolith generally occur in the lower parts of the landscape, but ancient depositional regolith may occur in topographically high locations if it is protected from erosion (covered or

1

cemented). In situ weathering profiles (Figure 1) occur throughout the landscape, but are likely to be observed in the higher parts, where they are not commonly covered by more recent sedimentary regolith. Areas with steep slopes normally feature eroded remnants of regolith, or fresh rock. Figure 2 illustrates the distribution of regolith in a typical landscape. Figure 3 illustrates a more complex regolith-landscape association in the Yilgarn, particularly showing the distribution of ferruginous materials. The terms ‘laterite’ and ‘ferricrete’ are widely used for surface iron-rich materials. Workers on the Yilgarn, and elsewhere, consider ‘laterite’ to be a residual accumulation of iron oxides, and ferricrete to result from the absolute accumulation of iron oxide in a previously existing regolith material. Profiles that have relative Fe- or Al-rich duricrusts are typically related to a weathering profile with a particular set of characteristics as shown in Figure 4. Calcretes (regolith carbonates or RCs) take many forms. They contain a variety of carbonate minerals, from pure calcite to dolomite, and have recently become an important gold exploration sampling medium. Figure 5 offers a classification and a genetic model for RCs.

Soil moves downhill taking fragments of vein with it, to form a stoneline (indicating downslope movement of the upper regolith).

Collapsed saprolite

This is weathered rock material that has undergone sufficient weathering that the original rock fabric is lost. It may move downslope taking the vein with it.

Saprolite with rounded corestones

Saprolite is chemically weathered rock that maintains the original rock fabric. It may contain a few rounded corestones of relatively fresh granite that may exhibit spheroidal weathering. Remnants of fracture and joints of the original rock may still be observed. The vein remains intact indicating that the saprolite is in situ. Corestones are pebble to boulder size remnants of fresh rock.

Saprolite with subrounded corestones

Here the corestones are not as weathered as above. Joints and fractures remain visible in the saprolite and the vein is also in situ.

REGOLITH

Soil Stoneline

WEATHERING FRONT Fresh rock

Fresh granite with joints and fractures and a vein. There may be minor weathering progressing down some joints and fractures.

FIG 1 - A typical in situ weathering profile with an explanation of the terms for parts of the profile. 1.

Information supplied by Dr G Taylor, Education and Training Coordinator, Cooperative Research Centre for Landscape Evolution and Mineral Exploration. P O Box 1, Belconnen, ACT 2616; Email [email protected]

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MINERAL AND ROCK INFORMATION

FIG 2 - Schematic diagram of regolith-landscape relations in the central Broken Hill block, after Figure 9 in Hill, S M and Kohn, B P, 1999. Morphotectonic evolution of the Mundi Mundi range front, Broken Hill region, Western NSW, Regolith ’98, pp 319-334 (CRC LEME: Perth, WA).

FIG 3 - Types of ferruginous materials, from Taylor, G and Butt, C R M, 1998. The Australian regolith and mineral exploration, AGSO Journal of Australian Geology and Geophysics, 17(4), 55-67.

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MINERAL AND ROCK INFORMATION

FIG 4 - Examples of various types of ferruginous regolith materials in a landscape context from the Yilgarn, WA, from Taylor and Butt (op cit).

FIG 5 - Genetic classification of calcrete, from Taylor and Butt (op cit).

Field Geologists’ Manual

59

3. GEOCHEMISTRY 3.1.1. PERIODIC TABLE OF THE ELEMENTS1

Notes: i.

Ionic radii of the elements are represented diagrammatically.

ii.

Coordination numbers for all elements are VI, except for Be, B, Si, Ge and P which are IV; K, Ti, Ba, Sr, Pb and Ra which are VIII; and Rb and Cs which are XII.

iii

The following valence states were used where there is a reasonable choice: 1 + for Tl; 2 + for Mn, Fe, Co, Ni, Cu, Hg and Pb; 3 + for V, Cr and B; 4 + for Sn, Mo, W and the platinum group; 5 + for Nb, Ta, P, As and Sb.

iv.

Data for unstable elements, noble gases, H, C and N, not included.

From:

Field Geologists’ Manual

1.

Levinson, A A, 1974. Introduction to Exploration Geochemistry. (Applied Publishing: Calgary), by permission.

2.

A more detailed periodic table, showing a range of elemental properties, is available from the Sargent-Welch Scientific Company, 7300 Linder Avenue, Skokie, Illinois, USA 60076.

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GEOCHEMISTRY

3.1.2. ALPHABETICAL LIST OF NATURAL ELEMENTS AND COMMON VALUES Element name

Symbol

Atomic weight1

Atomic number

Valence state2

Element name

Symbol

Atomic weight1

Atomic number

Valence state2

Actinium Aluminium Antimony Argon Arsenic Barium Beryllium Bismuth Boron Bromine Cadmium Calcium Carbon Cerium Caesium Chlorine Chromium Cobalt Columbium Copper Dysprosium Erbium Europium Fluorine Gadolinium Gallium Germanium Gold Hafnium Helium Holmium Hydrogen Indium Iodine Iridium Iron Krypton Lanthanum Lead Lithium Lutetium Magnesium Manganese Mercury Molybdenum

Ac Al Sb A As Ba Be Bi B Br Cd Ca C Ce Cs Cl Cr Co See Cu Dy Er Eu F Gd Ga Ge Au Hf He Ho H In I Ir Fe Kr La Pb Li Lu Mg Mn Hg Mo

227 26.98 121.75 39.95 74.92 137.34 9.01 208.98 10.81 79.90 112.40 40.08 12.01 140.12 132.91 35.45 52.00 58.93 Niobium 63.55 162.50 167.26 151.96 19.00 157.25 69.72 72.59 196.97 178.49 4.003 164.93 1.008 114.82 126.90 192.2 55.85 83.90 138.91 207.19 6.94 174.97 24.31 54.94 200.59 95.94

89 13 51 18 33 56 4 83 5 35 48 20 6 58 55 17 24 27

3 3 3, 5 — 3, 5 2 2 3, 5 3 1, 5 2 2 4, 2 3, 4 1 1, 3, 5, 7 6, 3, 2 2, 3

Nd Ne Ni Nb N Os O Pd P Pt Po K Pr

144.24 20.18 58.71 92.91 14.01 190.2 16.00 106.4 30.97 195.09 210 39.10 140.91

60 10 28 41 7 76 8 46 15 78 84 19 59

3 — 2, 3 5, 3 3, 5, 4, 2 2, 3, 4, 6, 8 2 2, 4 3, 5, 4 2, 4 2, 4 1 3, 4

29 66 68 63 9 64 31 32 79 72 2 67 1 49 53 77 26 36 57 82 3 71 12 25 80 42

2, 1 3 3 3, 2 1 3 3 4 3, 1 4 — 3 1 3 1, 5, 7 2, 3, 4, 6 2, 3 — 3 4, 2 1 3 2 7, 6, 4, 2, 3 2, 1 6, 5, 4, 3, 2

Neodymium Neon Nickel Niobium Nitrogen Osmium Oxygen Palladium Phosphorus Platinum Polonium Potassium Praseodymium Protactinium Radium Radon Rhenium Rhodium Rubidium Ruthenium Samarium Scandium Selenium Silicon Silver Sodium Strontium Sulphur Tantalum Tellurium Terbium Thallium Thorium Thulium Tin Titanium Tungsten Uranium Vanadium Xenon Ytterbium Yttrium Zinc Zirconium

Pa Ra Rn Re Rh Rb Ru Sm Sc Se Si Ag Na Sr S Ta Te Tb Tl Th Tm Sn Ti W U V Xe Yb Y Zn Zr

231 226.05 222 186.2 102.91 85.47 101.07 150.35 44.96 78.96 28.09 107.87 22.99 87.62 32.06 180.95 127.60 158.92 204.37 232.04 168.93 118.69 47.90 183.85 238.03 50.94 131.30 173.04 88.91 65.37 91.22

91 88 86 75 45 37 44 62 21 34 14 47 11 38 16 73 52 65 81 90 69 50 22 74 92 23 54 70 39 30 40

5, 4 2 — 7, 6, 4, 2, 1 2, 3, 4 1 2, 3, 4, 6, 8 3, 2 3 2, 4, 6 4 1 1 2 2, 4, 6 5 2, 4, 6 3, 4 3, 1 4 3, 2 4, 2 4, 3 6, 5, 4, 3, 2 6, 5, 4, 3 5, 4, 3, 2 — 3, 2 3 2 4

1.

Atomic weights from International Union of Pure and Applied Chemistry, Compt. Rend., XXIII Conf., pp 177-178, 1965. 12 Based on atomic mass of C = 12; rounded to two decimal places.

2.

Most stable valence state shown first.

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GEOCHEMISTRY

3.1.3. CONVERSION FACTORS, ELEMENTS TO COMPOUNDS ELEMENT FACTOR COMPOUND ELEMENT FACTOR COMPOUND ELEMENT FACTOR COMPOUND Al

1.889

Al2O3

1.382

Fe3O4

P

2.291

P2O5

As

1.320

As2O3

1.286

FeO

Pb

1.077

PbO

1.534

As2O5

1.574

FeS

3.220

B2O3

Hf

1.179

HfO2

Rb

Hg

B Ba

Fe

1.117

BaO

1.699

BaSO4

Be

2.775

BeO

K

Bi

1.115

Bi2O3

Ca

1.399

CaO

2.497

CaCO3

1.948

CaF2

1.142

CdO

Cd Ce Co Cr

1.171

Ce2O3

1.228

CeO2

1.271

CoO

1.362

Co3O4

1.462

Cr2O3

PbS

1.094

Rb2O Sb2O3

1.080

HgO

Sb

1.197

1.160

HgS

Si

2.139

SiO2

1.205

K2O

Sn

1.270

SnO2

La

1.173

La2O3

Sr

1.183

SrO

Li

2.153

Li2O

Ta

1.221

Ta2O5

5.324

Li2CO3

Th

1.138

ThO2

1.658

MgO

Ti

1.668

TiO2

3.468

MgCO3

U

1.179

U3O8

Mg Mn

1.291

MnO

1.202

UO3

1.582

MnO2

1.134

UO2

Mo

1.500

MoO3

V

1.785

V2O5

1.668

MoS2

W

1.261

WO3

Na

1.348

Na2O

Y

1.270

Y2O3

Zn

1.245

ZnO

Cs

1.060

Cs2O

2.542

NaCl

Cu

1.252

CuO

Nb

1.431

Nb2O5

F

2.055

CaF2

Ni

1.273

NiO

Fe

1.430

Fe2O3

Field Geologists’ Manual

1.155

Zr

1.490

ZnS

1.351

ZrO2

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GEOCHEMISTRY

3.2. AVERAGE ABUNDANCE OF SELECTED MINOR ELEMENTS IN THE 1 EARTH'S CRUST

64

Field Geologists’ Manual

GEOCHEMISTRY

Notes : 1.

From Levinson, A A, 1974. Introduction to Exploration Geochemistry. (Applied Publishing: Calgary), by permission.

2.

All values in ppm except those for river water which are ppb.

3.

Dashes (—) indicate no data are available.

3.3. RANGE OF ABUNDANCE OF TRACE ELEMENTS IN SOILS

1

Range of common values shown by a solid line, with unusual values shown by a dashed line.

1. Principally from: Swaine, D J, 1955. The trace element content of soils. Tech. Comm. 48, Comm. Bur. Soils Sci., by permission.

Field Geologists’ Manual

Additional elements from: Andrews-Jones, D A, 1968. The application of geochemical techniques to mineral exploration. Colo. Sch. Mines., Min. Ind. Bull 11, by permission.

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GEOCHEMISTRY

3.4. GEOCHEMICAL SIGNATURE OF MINERAL DEPOSIT TYPES

66

1

Field Geologists’ Manual

GEOCHEMISTRY

From: 1.

Cox and Singer, 1986. Mineral Deposit Models. US Geological Survey Bulletin 1693.

2.

Olympic Dam Cu-U-Au-Ag deposit is hosted by diverse breccias, including hydrothermal, phreatomagmatic, fault-related and epiclastic types. Reeve et al, 1990.

Field Geologists’ Manual

Olympic Dam copper-uranium-gold-silver deposit, in: Geology and Mineral Deposits of Australia and Papua New Guinea, Monograph 14 (Ed: Hughes, F E), pp 1009-1035 (The Australasian Institute of Mining and Metallurgy: Melbourne).

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GEOCHEMISTRY

3.5. APPROXIMATE LOWER DETECTION LIMITS, IN PPM, FOR THE 1 COMMON GEOCHEMICAL ANALYTICAL METHODS Element

AAS

ICPAES 2

ICPMS

Ag Al As Au

1 100 20 0.001

1 (0.1) 10 1 (0.2) 0.01

0.1 10 1 0.001

20 0.1 5

10 5 0.1 5 (0.2)

10 1 0.02 0.2

10 1 (0.1) 20 5 5 10 2 (1) 10 10 1

0.1 0.1 0.1 1 0.2 1 0.1 0.1 0.1

10 10 10 20 10 (0.5) 20

10 0.2 0.1 1 0.5 0.1 0.1

10

20

0.1

10

10 5 5 10 10 5 2 (0.2) 10 10 10 5

0.1 0.2 0.1 10 1 0.2 10 0.2 0.1 1

10 5 (1) 0.01 10 0.01 10

1 1 0.001 0.1 0.001 0.2

B Ba Be Bi Br Ca Cd Ce Co Cr Cs Cu Dy Er Eu F Fe Ga Gd Ge Hf Hg Ho I In Ir K La Li Lu Mg Mn Mo Na Nb Nd Ni Os P Pb Pd Pr Pt Rb

68

10 1 2 5 2

XRF

5

Comments3 0.1 by solv. ext. AAS Fusion recommended 1 by hydride gen. AAS 0.1 ppb by Zeeman-GF AAS, 0.05 ppb Au by cyanide leach

10 5 5 10 20

10 5

10 by fusion + SIE 10

0.05 (cold vap.)

4 10 by colorimetry 10 0.001 by NiS fire assay

10 5 2 10 300 2

20

4 2

0.001 by NiS fire assay 5 0.01 0.01

5

10

Field Geologists’ Manual

GEOCHEMISTRY

Element Re Rh Ru S Sb Sc Se Si Sm Sn Sr Ta Tb Te Th Ti Tl Tm U V W Y Yb Zn Zr

AAS

5

5 10

1

ICPAES 2

10 5 (0.2) 1 (0.5) 100 10 10 5 10 10 (0.5) 20 10 (0.5) 10 20 5 5 5 10 2 (1) 10

ICPMS 0.1

XRF

Comments 3 0.001 by NiS fire assay 0.001 by NiS fire assay 100 by LECO

0.2 1 0.5

4 2 Fusion necessary

0.1 0.2 1 0.2 0.1 0.2 0.1 10 0.1 0.1 0.1 1 0.2 0.1 0.1 1 1

5 5 10 10 4 10

4 10

5 10

Notes:

Field Geologists’ Manual

1.

Data supplied by ALS Chemex, Brisbane. Shaded areas denote recommended method(s).

2.

The lower limits of detection available with acid digestion-solvent extraction and ICPAES are shown in brackets.

3.

Many elements can also be determined to low limits of detection by Neutron Activation Analysis, available from Becquerel Laboratories, Lucas Heights, NSW.

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GEOCHEMISTRY

3.6. GENERAL NOTES FOR GEOCHEMICAL SAMPLING RECORDING THE SAMPLE ENVIRONMENT Some organisations use standard forms for recording sample data, which enforce a full description of the sample environment. The environment is then used as a background in the comparison of sample analyses. Information recorded by the sampler may be: Stream sediment samples Project name or number, sample number. Date and sampler's name. Location: Regional map name or number, scale, coordinates; air photo identification and scale; local or organisation plan name or number, scale and coordinates. Catchment Data: Drainage system name, catchment area, catchment geology, vegetation type. Stream Data: Stream name, size (large, medium, small, swamp), flow rate, bed slope, stream bank description (depth and description of weathered profile), elevation and datum. Sample Site Outcrop Geology: Weathering, lithology, foliation geometry. Sample Site Sediment Data: Distribution of stream sediment sizes (per cent boulders, cobbles, pebbles, sand, mud), distribution of stream sediment lithologies, organic content, precipitates, water colour and taste, estimate of heavy minerals and ore minerals. pH, Eh, conductivity, radioactivity. Mesh size used, estimated weight of sample collected. Analyses: Sample preparation and analyses required.

Date and sampler's name. Location: Regional map name or number, scale, coordinates; air photo identification and scale; local or organisation plan name or number, scale and coordinates, elevation and datum. Regional Data: Regional geology (lithological formation or unit), topography, vegetation. Sample Site Outcrop Geology: Weathering, lithology, foliation geometry. Type of Sample: Specimen, grab sample (number and size of pieces taken), chip sample (dimensions of area sampled, spacing of chips), channel sample (channel length, width, depth, bearing, slope), drillhole cuttings (length sampled, per cent recovery), drill core (core size, interval sampled, per cent of length of core recovered). Volume or weight of sample. Sample Geology: Lithology, weathering, rock foliation geometry, veining, hardness, colour, moisture content, description of ore minerals, visual estimate of grade. Analyses: Sample preparation, analyses, thin or polished section, etc. Preferred sample weight Water samples: 100 ml to 1 litre. Geochemical stream sediments: 100 g. Stream sediment samples for heavy mineral separation: min. 1 kg. Rock chip or drill cuttings samples1: Dependent on the diameter of the largest individual mineral grains, viz : Grain diameter

Soil samples Project name or number, sample number. Date and sampler's name. Location: Regional map name or number, scale, coordinates, distance, bearing and slope angle from previous sample site, elevation and datum. Regional Data: Regional geology (lithological formation or unit), topography, vegetation. Sample Site Outcrop Geology: Weathering, lithology, foliation geometry. Sample Site Data: Transported or residual soil, depth of sample, soil profile description. Horizon sampled, colour, distribution of grain sizes, soil composition, wet or dry. Sample Lithology: Description of rock fragments (weathering, colour, inferred lithology), ore minerals. Field Sample Preparation: Screening, mesh used, estimate of sample weight collected. Analyses: Sample preparation and analyses required. Rock samples Project name or number, sample number.

70

Size description

Sample weight 5 kg

+ 30 mm

‘pegmatitic’

10 to 30 mm

‘coarse grained’

2 kg

1 to 10 mm

‘medium grained’

1 kg

– 1 mm

‘fine grained’

500 g

Rock samples for age determination: i.

K/Ar: Minimum 2 g biotite, 2 g muscovite or 6 g hornblende—usually available in 1 kg of fresh rock, selected as four hand specimen size pieces from a wide area of the same lithological unit.

ii.

Rb/Sr: About 2 kg of rock, from as close as possible at the same location, as perhaps ten lumps, and showing the widest possible range of K-feldspar:plagioclase:mafics ratio.

iii.

Pb: One speck of galena from a polished section is sufficient.

1.

See also Kleeman, A W, 1967. Sampling error in the chemical analysis of rocks. Jour. Geol. Soc. Aust. (14) 1: 54-57.

Field Geologists’ Manual

GEOCHEMISTRY

iv.

U: A mixed representative sample, about 2 kg of rock, containing a few micrograms of uranium.

Drill core sample interval:

Percussion drill samples Use good quality calico bags with incorporated tie string and tag on side of bag. Open texture cloth bags can allow fine material (often economic mineral) to sift from bag and even re-enter another at a lower level. Preferably use a plastic bag liner. Do not use aluminium tags if sulphides or chlorides are present. ‘Dymo’ tape labelling is preferable.

i.

With significant and irregular core losses, then individual coring runs, as shown by the drillers core markers, should be taken as individual samples. The coring interval, and length of core recovered, are recorded.

ii.

With minor uniform core loss, or complete core recovery, lengths of core may be marked for sampling, with a measurement accuracy of about 10 mm per metre core length (±1 per cent) . To minimise the effect of inaccuracies in measurement, the minimum core sample length taken in uniform lithology or mineralisation is usually one metre.

Rock samples

iii.

Where isolated narrow mineralised features occur, of core length less than one metre, these may be taken as one sample.

iv

With rocks of coarse or pegmatitic grain size, and small diameter core, lengths greater than one metre may be required to provide an acceptable sample weight. For example, with core of BQWL size (volume is 0.00104 m3/m core length from Table 10.1) in pegmatitic granite (density is 2.7 t/m3 from Table 7.3.4.), a minimum sample weight of 0.005 t is required (see data on rock sampling above). 0.005 Minimum core length = 2.7 × 0.001 04

To obtain analyses representative of geological samples, one requires some understanding of laboratory procedures so that the analyst may be provided with clear instructions. The common brief instruction ‘geochemical Cu Pb Zn Au’ is not sufficient when a wide range of sample preparation and analytical procedures are available for these elements. Ideally before any field sampling begins, the geologist should decide (by discussion with the geochemist or chemist of the service laboratory), the most suitable procedures to be adopted. The most important aspects would be: Sample preparation– Advise chemist of degree of homogeneity of material to be submitted. Bearing in mind mineral composition of the samples, discuss with the chemist the degree and stages of comminution during preparation to obtain representivity and homogeneity in the sample for analysis. Digestion– Choose a method of sample attack to release elements of interest. Partial or selective digestion may provide useful information. Analytical method– Select an analytical method to provide the sensitivity and the precision required. Reporting– The turnround period is usually arranged by prior agreement with the service laboratory. Determine the method of reporting— telephone, telex, mail, e-mail. Storage– The laboratory should be instructed in writing on the disposal or storage of samples. These instructions, however, are not usually given until analytical results are received.

= 1.78 metres

PREFERRED SAMPLE PACKAGING AND LABELLING METHODS Geochemical sample containers Use kraft envelopes with aluminium tie, leak-proof sides of envelope gummed with PVC. Turn tie over twice to prevent leakage of sample. Reference number should appear at top of packet after turning tie. Kraft envelopes allow sample to dry within packet and are much easier to handle than plastic bags.

Field Geologists’ Manual

If rocks are to be analysed, enclose in plastic bags at the point of collection. Sample numbers can be impressed on ‘Dymo’ tape or cloth reinforced labels.

SAMPLE SUBMISSION AND ANALYSIS INSTRUCTIONS

71

72

Numerical data grouped into consecutive classes. (Croxton and Cowden, p. 168)

Magnitude of the range of values covered by each class. (Arkin and Colton, p. 2)

Classified data (see frequency distribution)

Class interval

C

A subdivision of the observed range of a variable, having stated limits. (Arkin and Colton, p. 2)

Class

frequency. (Arkin and Colton, p. 109-l 12)

frequencies to theoretical frequencies; fo = observed frequency, f = theoretical

χ2 Test to determine goodness of fit of observed

Successive terms of the expansion give probabilities of 0, 1, 2, 3 - - - n, items in a sample of size n, having a characteristic which is found in the proportion p of items in the population from which sample was taken, and is absent in the proportion q, (p+q=1). (Moroney, p. 88-94)

Bimodal distribution ( q + p )n

Chi square (fo − f) 2 χ2 = ∑ f

A frequency distribution with two maxima. (Arkin and Colton, p. 5)

Probability of accepting a hypothesis when it is false. (Dixon and Massey, p. 80-81)

Arrangement of numerical data in order of increasing magnitude. (Croxton and Cowden, p. 165)

The average of a group of items. (Arkin and Colton, p. 11)

The numerical value of an item regardless of its sign. (Davies, p. 256)

Definition

Bimodal distribution

β

X

Arithmetic mean Σx X= n

Array

||

Absolute value | X | = the absolute value of X

Term, Symbol and Formula

Dependent variable

Degrees of freedom

Cumulative distribution

Covariance

1 Σ ( x − x )( y − y ) r = n σx . σx

Y

The variable whose magnitude is plotted as a function of fixed consecutive values of a second (independent) variable. (Arkin and Colton, p. 4)

d.f. The number of items that are free to vary; if a mean value has been calculated, the value of any item is fixed by the sum of the others, so that d.f. = n − l. (Croxton and Cowden, p. 312)

An array showing proportion of total greater than, or less than, each recorded value of a variable. (Croxton and Cowden, p. 184)

The expected (mean) value of the product of the deviations of two variables from their respective means. (Davies, p. 246)

A measure of correlation; x and y = mean values of x and y, σx and σy = standard deviations of x and y; (limit of | r | = 1). (Moroney, p. 286; Croxton and Cowden, p. 931)

Correlation Coefficient

A table of frequency data arranged under more than one classification. (Davies p. 244)

The range within which the true value may be expected to fall with a stated probability. (Moroney, p. 238-240)

Measure of relative dispersion; σ = standard deviation; X = arithmetic mean (Arkin and Colton, p. 40)

Degree of association between two variables. (Dixon and Massey, p. 3) r

V

Definition

Correlation

Contingency table

Confidence interval (see Fiducial interval)

Coefficient of variation σ V = .100 X

Term, Symbol and Formula

3.7. GLOSSARY OF STATISTICAL TERMS AND SYMBOLS

GEOCHEMISTRY

Field Geologists’ Manual

Field Geologists’ Manual

Antilogarithm of logarithmic standard deviation. (Shoemaker, and others, p 32)

Geometric deviation

Geometric mean Gm The antilogarithm of the mean of the logarithms of individual values. (Arkin and Colton, p 26) n Gm = X1. X2. X3 − − − − Xn

A table or graph showing the relative frequencies of items having the various possible values of a specified variable. (Moroney, p 44)

Frequency distribution

The number of items in a specified category, usually a class. (Dixon and Massey, pp 6, 8)

f

Frequency

The product of every integral number in a series multiplied together. (Davies, p 257)

The interval within which a true value may be said to fall, with a stated probability. (Moroney, pp 238-240)

!

Fiducial interval ( see Confidence interval)

Factorial X! = Xn. Xn –1. Xn_ 2 ---1

statistic whose distribution measures the significance of the difference between two sample variances, where σ1 > σ2 (Dixon and Massey, pp 84-85)

A

σ 12 σ 22

F

F=

The base of the natural, or Naperian, system of logarithms. (Croxton and Cowden, p 924)

e

a

e = 2.71828 = limit 1+1/!1+1/!2 +1/!3+---+1/

degree of variation of data around representative value. (Arkin and Colton, p 8)

The difference between an observed value and a standard, which is usually a mean. (Moroney, p 60)

The

d

Definition

Dispersion

Deviation

Term, Symbol and Formula

4

σL =

Σ( XL − XL ) n −1

Log-standard deviation

Log-normal distribution

Level of significance

Leptokurtic

Kurtosis ΣX π4 = n

Independent variable

Histogram

∑x

Harmonic mean N 1

Hm =

2

Definition

σL

α

π4

The standard deviation, expressed as a logarithm, of the logarithms of the original sample values. (Shoemaker and others, p 28)

A skewed frequency distribution with a mode in the low values, such that the logarithms of the original data yield a normal frequency distribution. (Croxton and Cowden, p 293)

Probability of rejecting a hypothesis when it is true. (Dixon and Massey, p 80)

A narrow, high peaked curve. (Croxton and Cowden, pp 258-259)

A measure of the peakedness or flatness of a curve. (Croxton and Cowden, pp 258-259)

X The variable whose magnitude changes systematically; X also used to denote values of a single random variable. (Arkin and Colton, p 4)

A frequency distribution expressed as a bar chart; width of bar represents class interval, height of bar represents frequency (Moroney, pp 22-23)

Hm The reciprocal of the arithmetic mean of reciprocals of individual values. (Croxton and Cowden, p 226)

Term, Symbol and Formula

GEOCHEMISTRY

73

74

The most common value, corresponding to the peak of the frequency distribution. (Arkin and Colton, pp 23-27)

Mode

A symmetrical bell shaped curve asymptotic to the X axis, - - the normal curve of error. (Dixon and Massey, pp 47-49)

Normal distribution 2    X -µ   1 1 −2 σ   Y=σ e  2π Null hypothesis

A cumulative frequency distribution table, histogram, or curve. (Arkin and Colton, pp 4-5)

In, experimental design, designed so that for each level of any independent variable, all levels of the other independent variables are represented. (Davies, p 251)

Ogive

Orthogonal

Ho The hypothesis that no significant difference exists between two items that are being compared statistically. (Croxton and Cowden, pp 310-311)

Independent of the nature of the population distribution. (Dixon and Massey, p 247)

Non-parametric

N Number of items in a sample, sometimes N = number (n) of items in a finite population, where n = number of items in a sample from that population. (Croxton and Cowden, p 928)

Value of the middle item in an array of numerical data, an average of position. (Arkin and Colton, pp 19-21)

MD The mean of the absolute values of the deviations of individual items from the group mean. (Arkin and Colton, pp 31-33)

Definition

Median

Mean deviation Σ| d | MD = n

Term, Symbol and Formula

n

ΣX 2

Regression line

Range

Random sample

Qm =

Probable error . P.E. = 0.6745σ Quadratic mean

A class or aggregate of objects or events from which a sample is taken. (Krumbein, p 349)

2.

The median of the frequency distribution of errors. (Arkin and Colton, p 115)

Graph paper on which cumulative normal frequency distributions plot as straight lines. (Dixon and Massey, p 56)

The theoretical true mean value, of which the sample mean is an estimate. (Dixon and Massey, p 33)

The entire body of data from which a sample is taken. (Arkin and Colton, p 113)

1.

W

The line, or curve from a family of curves, on a scatter diagram, which best fits the empirical relation between a dependent variable and an independent variable. (Arkin and Colton, p 76)

The largest and smallest values in a sample, or the difference between these values. (Arkin and Colton, p 29)

A sample taken in such a way that all items in the sampled population have an equal and independent chance of appearing in it. (Dixon and Massey, p 34)

Qm The square root of the mean square of the items in a sample. (Arkin and Colton, p 27)

P.E

µ

Population mean

Probability paper

P

A broad, low peaked curve. (Croxton and Cowden, p 258)

Platykurtic

Population

Any measurable characteristic of a sample or a population. (Dixon and Massey, p 33)

Definition

Parameter

Term, Symbol and Formula

GEOCHEMISTRY

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Field Geologists’ Manual

σ (s)

X1 − X2 σx 1 − x 2

Variance Σ( d 2 ) σ2 = n −1

Trend line

t=

Systematic sample

The line or curve on a graph, expressing the best empirical relationship between two variables, commonly a regression line. (Moroney, p 285)

The ratio of a statistical measure, normally distributed about a mean of zero, to an estimate of the standard error of that measure. (Croxton and Cowden, p 940)

Samples collected at regular pre-determined intervals, such as intersections of a grid. (Krumbein, p 360)

The sum of variables in a series. (Arkin and Colton, p 206)

The standard deviation of a calculated statistical measure. (Arkin and Colton, p 115)

The square root of the variance, σ commonly = population standard deviation, where s = sample standard deviation. (Arkin and Colton, p 33)

σ2 The sum of the squared deviations from the mean (s2) divided by the degrees of freedom; the standard deviation squared. (Dixon and Massey, pp 19-22)

t

Summation symbol Σ ΣX = X 1 + X 2 + X 3 + ---Xn.

Standard error

Standard deviation Σ( d ) 2 σ= n −1

The degree of distortion from symmetry exhibited by a curve. (Arkin and Colton, pp 40-41)

Skewness

Definition

That part of the total which is not accounted for by assigned factors; in analysis of variance, the difference between the sum of assigned sums of squares and the total sum of squares. (Dixon and Massey, p 129)

Term, Symbol and Formula

Residual

1.

—

Definition

REFERENCES

The mean value (X), or the estimated value in a population, of a statistical measure calculated from a sample, as σ. (Davies, p 256)

The difference between the natural logarithms of two independent estimates of the standard deviation. (Davies, p 262)

A mean obtained by multiplying each item by a correction factor and dividing the total by the sum of the correction factors. (Arkin and Colton, pp 134-135)

From Lovering, T G. Glossary of statistical terms used in geological reports. American Geological Institute, Data Sheet 28, by permission.

Arkin, H and Colton, R R, 1955. Statistical Methods (Barnes and Noble: New York). Croxton, F E and Cowden, D J, 1939. Applied General Statistics (Prentice-Hall: New York). Davies, O L, 1949. Statistical Methods in Research and Production (Oliver and Boyd: London). Dixon, W J and Massey, F J Jr, 1951. Introduction to Statistical Analysis (McGraw-Hill: New York). Krumbein, W C, 1960. The geological population as a framework for analysing numerical data in geology, Liverpool and Manchester Geol. Jour. (2) 3:341-368. Moroney, N J, 1953. Facts from Figures (Penguin: London). Shoemaker, E M, 1959. Elemental composition of the sandstone-type deposits, in Geochemistry and mineralogy of the Colorado Plateau uranium ores. USGS Prof. Paper 320:25-54. Till, R, 1974. Statistical Methods for the Earth Scientist: An Introduction (Macmillan: London).

Superscript bar

z = 12 log e F

z

Term, Symbol and Formula Weighted mean

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75

70

80

90

95

98

99

99.8 99.9

99.99

95

98

99

99.8 99.9

99.99

1

4

4

90

5

5

80

7 6

7 6

70

1 9 8

1 9 8

60

2

2

50

3

3

40

4

4

1

5

5

2

7 6

2

1 9 8

1 9 8 7 6

3

2

2

3

3

4

5

7 6

1 9 8

3

30

60

20

50

10

40

5

30

2

20

1

10

0.5

5

0.05 0.1 0.2

2

0.01

1

4

0.5

5

0.05 0.1 0.2

7 6

0.01

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GEOCHEMISTRY

3.8. PROBABILITY × 3 CYCLE LOG PAPER

Field Geologists’ Manual

4. MINING AND ECONOMIC GEOLOGY 4.1.1. GUIDELINES FOR ENVIRONMENTAL CARE IN MINERAL EXPLORATION The community judges the exploration and mining industries by their environmental performance. Future access to land for exploration depends on all exploration personnel demonstrating responsible environmental management and concern for other stakeholders in land. Environmental legislation now contains severe penalties, including personal liability and criminal sanctions for both senior managers and operators, for breaches of duty of care and for pollution. Companies should establish environmental management systems for exploration, which set performance and training standards, criteria for measuring good performance and methods for monitoring and improving performance. Guidance for doing this is given in the ISO 14 000 series of Standards for Environmental Management Systems (available from Standards Australia) and in the minerals industry Code for Environmental Management 2000 (available from Minerals Council of Australia), signatories to which undertake to establish such systems. There is a large number of exploration and other field practice guidelines available from professional and industry associations, state and territory governments and exploration companies themselves. For example, AusIMM has an Environmental Policy and Institute of Geoscientists (AIG) has a ‘Field Operators Guide’. Some codes are available as handy, pocket-size, weather-proof booklets. Entry onto land entails legal responsibilities and each guide or code begins with the need to become familiar with these in the particular local context, and to inform land holders of the work proposed. A second fundamental principle common to all is the need to delineate sensitive areas and to plan activities, in order to minimise unnecessary disturbance. Thirdly, undertake training and prepare plans to deal with spills and other incidents. Fourthly, rehabilitation of disturbance, based on sound science, should be carried out, with special emphasis on complete closure of drillholes and removal of sample bags. A code, and useful background information, is available in a booklet on environmental management for exploration ‘Onshore Minerals and Petroleum 1.

Prepared by Graeme Mcllveen, Corporate Environment Services Pty Limited, Brisbane, Australia.

2

Modified from: Environmental Checklist for Exploration. Placer Exploration Limited. Appendix A in White, G and O'Neill, D, with Morozow O, June 1996. Onshore Minerals and Petroleum Exploration. Best Practice Environmental Management in Mining. Environment Protection Agency. Canberra, Australia.

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1

Exploration’) in the series of ‘Best Practice Environmental Management’ booklets produced by the commonwealth government agency Environment Australia, available through the Minerals and Energy Environment Foundation (AMEEF). This contains references to other codes and guidelines; the example ‘Environmental Checklist’ given here is modified from that prepared by Placer Exploration Limited and given in Appendix A of that publication. Many items on the checklist are or may be required by law (such as contacting land owners or occupiers); indeed some state codes are mandatory (such as that in New South Wales). This checklist, or similar guidelines, should therefore be adopted in the absence of mandatory regulations. ENVIRONMENTAL CHECKLIST

2

PRE-EXPLORATION

Co-ordination 1.

Select the member of the field crew who, as Field Coordinator, will be responsible for ensuring that (company’s) commitments are met.

2.

Discuss with the Field Coordinator any special natural and/or social aspects of this project’s environmental protection program.

Communication 3.

4.

5. 6.

7.

8.

Determine who owns, leases or uses or occupies the land and contact the owner, lessee or land user or occupier. Obtain the necessary permits or approvals from local, state or national authorities and from the landholder. Prepare a plan (such as an annotated map) for the local landholders. Contact local government authorities, media outlets and other interested parties that may be able to provide advice or assistance in conducting the project. Provide a set of (company’s) Environmental Policy and guidelines to all employees and contractors. Advise all field staff of special requirements or restrictions that will apply for this program and location.

Contractors 9.

Inspect all contracts, to check that all contractors are aware of and accept previously agreed responsibilities for environmental protection.

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MINING AND ECONOMIC GEOLOGY

10. Determine that all contractors carry appropriate compensation and public liability insurance. Assessment 11. Investigate and note in writing whether the exploration area has special values or is sensitive in some way (particularly in a way which may not be immediately obvious to exploration staff or contractors):

•

•

has high agricultural or pastoral value or special concerns about (for example) breeding times (lambing), crop growth or harvesting; is at risk from plant infection or disease (such as fungal ‘die-back’ transmitted on dirty vehicles and footwear), weeds (also carried in mud/soil on vehicles) or feral animals (no pets should be allowed);

•

has aboriginal cultural or archaeological significance (there are essential statutory requirements in Australia for this clearance to be obtained), or other cultural or heritage value (such as old mine equipment);

•

has high conservation values, which may include rare or endangered plants and animals, important groups of living things (ecosystems), or heritage items or sites such as old mine buildings;

•

has valuable water resources (including groundwater resources) or special or sensitive water bodies such as lagoons;

•

is or may be affected by special entry or other access restrictions (such as land used for military purposes or water storage catchments);

•

has seasonal restrictions, such as fire sensitivity; and

•

has potential for community concerns about exploration, for example due to pre-existing unrehabilitated works.

12. Write a report and prepare a map indicating various sensitive or special areas and setting out the rules and means for protecting them by restricting entry and/or minimising disturbance to each. Communicate this to all project staff. 13. Take photographs of sensitive or potentially sensitive sites (tracks, water bodies and supplies, important and typical bush land/flora, at or near sites to be disturbed). 14. Check and learn the conditions attached to the exploration tenement by the state Department of Minerals and Energy (or similar) and any authority from the state Environmental Protection Agency (or similar). Inform all exploration staff

78

of them. Attach a copy of them to this checklist to allow easy reference to them during the project. 15. Visit the site with local landholders or special interest or community groups to assess special site requirements and to communicate information about the project. 16. Arrange for all vehicles, drill rigs and other equipment to be checked for environmental suitability (cleaned of mud, seeds, no fuel or chemical leaks). 17. Initiate, review, circulate and act on reports from specialists (botanists, ecologists, archaeologists) that may be a pre-requisite for ground-disturbing activities. 18. Provide working fire-fighting equipment in vehicles and at campsites. 19. Consider holding a short training course to ensure all project staff and operators are familiar with the overall exploration checklist, the legal responsibilities they have and the particular or special issues for the specific project. DURING EXPLORATION

Campsite 20. Position it away from high value vegetation, sites of cultural and aboriginal significance or other special areas. Consider the relationship with existing access tracks to minimise the making of new ones and minimise the clearing of vegetation. 21. Position it more than 100 metres from the nearest water body (to minimise the risk of pollution). Be aware of the risk of flooding. 22. Take all necessary precautions to protect the camp and fuel storages from both approaching wildfire and to prevent the escape of fire from within the site. 23. Position both toilet and other organic waste and refuse facilities to have negligible impact on water quality and to be protected from feral and native animals - consider the possibility, even in remote areas, of complete removal of all solid rubbish/refuse - it should be buried as a minimum and covered by at least a half metre of soil. Roads and tracks 24. Use existing roads and tracks in preference to making new ones (unrestricted and uncontrolled vehicles making superfluous tracks, whether bulldozers or four wheel drives, must be one of the most common complaints levelled against exploration). 25. If and when new access must be constructed,

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clearly define, mark out and avoid areas and places having significant natural and cultural values. 26. Design, position, and construct new roads and tracks to accept stormwater runoff without erosion and to not concentrate flows to cause erosion beside the track or siltation in nearby watercourses. 27. Where new tracks leave from existing roads, add a ‘dogleg’ and conceal the exit point, with a windrow for example, to discourage casual use. Drilling 28. Position drill pads/holes on previously disturbed land if possible (existing tracks for example), or where damage to vegetation will be minimal. Construct pads, as for tracks, to minimise erosion and thus siltation, and to facilitate rehabilitation. 29. Design and construct drill sumps to contain all slurries, with spare capacity available for emergency flows. Consider the use of biodegradable drilling fluids. 30. If drilling or shaft dewatering are likely to bring saline water to the surface, ensure that soil and vegetation are not damaged by salt. Protection of vegetation 31. Reduce the risk of fires by banning multiple camp fires and restrict smoking in the field. 32. Investigate alternative exploration techniques that either do not require removal of vegetation, or require only minimal clearing, to be effective. 33. Ensure that the minimum amount of vegetation is cleared during track, grid line and drill pad construction; for example, ensure that the width of cleared tracks is kept to the minimum necessary. 34. Where vegetation is cleared, ensure damage to roots and soil is minimised, to allow the seed 'bank' in topsoil and the rootstock to regenerate; for example, bulldozer blades can run over the ground surface. 35. Investigate alternative methods to clearing, such as the use of heavy rollers to flatten vegetation without killing or removing it, or the use of low pressure tyre vehicles. 36. Ensure excavations such as costeans are kept to the minimum size necessary for safe completion of the job. Ensure vegetation cleared for the excavations is stockpiled fur re-spreading over them when they are back-filled. Ensure spoil from the excavations is placed to avoid destruction of vegetation.

Field Geologists’ Manual

37. Be aware that disturbed ground and spoil attracts introduced pest plants as colonizers, and may lead to them being introduced into a new area. Protection of topsoil 38. Ensure that the topmost layer of soil is excavated (’stripped’) and stored separately to the underlying ‘sub-soil’ and that it is stored in mounds less than two metres high to allow its inherent store of seeds to survive for regeneration when respread. 39. Refill the excavation and re-spread topsoil onto the fill and the disturbed area immediately after the excavation has served its purpose. Prevention of liquid and solid spillages 40. Check and ensure that all regulations that apply to the storage and use of fuel, chemicals and other liquids and solids, are known, are understood and are being followed by all staff, operators and contractors. Legislation can include personal criminal liability for accidental spillages for any or all of operators, senior managers and company directors. 41. Ensure that routine maintenance programs are conducted to prevent leakages or spills from machinery and equipment. Conduct checks of operations and contractors in the field. 42. Prevent runout of camp waste water and sewage; direct them to lined ponds to which animals are denied access. Litter 43. Provide bins for litter in campsites and carry out checks for litter around camps and drill sites. 44. Check that the designated refuse disposal area is neat and tidy, and that unauthorised disposal of special items, such as chemical or oil drums or organic refuse such as food scraps, is not taking place. Make it clear, by signage, that such materials must be taken to an authorised site or removed altogether. Communication 45. Ensure that any requests for information from landholders, special interest groups (such as conservation groups or local political bodies) and the community are being adequately, quickly and respectfully attended to. 46. Visit landholders to advise them that work has commenced; visit them to advise on progress and to ask if they have any concerns.

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47. Check and ensure that contractors have complied with all (company’s) contracts and exploration codes.

53. Check that all conditions of the exploration or mining title, and of any other licence issued by a regulatory authority, have been met.

After exploration

54. Invite landholders to tour the sites to provide satisfaction with clean-up and rehabilitation.

48. Ensure that all drill holes have been filled or capped according to regulation and to (company’s) policy and codes. Research has found that holes left uncapped, or on which the capping later fails, trap and kill significant numbers of small mammals and reptiles. Consider use of the ‘KNO’-style capping3.

55. Put monitoring procedures in place, such as inspections under appropriate seasonal conditions, for a defined period after completion of rehabilitation. Take photographs of disturbed sites after use and after rehabilitation (try to match images taken before disturbance - [item 13]).

49. Ensure that all rubbish, including sample bag, has been removed or buried under at least half a metre of cover, Ensure that all grid pegs are removed or laid flat. 50. Ensure that all excavations, including drill sumps, have been back-filled and the surface top-soiled and rehabilitated. 51. Ensure that all tracks that are not specifically agreed to be left in place are ripped and windrows flattened, and access is blocked and concealed. 52. Ensure that all disturbed areas have been rehabilitated to (company’s) codes and requirements (as a minimum, surface ripped, topsoil and old cut vegetation respread, seeds scattered and/or seedlings planted).

56. Consider having in (company’s) management system a process for documenting, reporting and signing-off on an environmental assessment of the exploration program, its impact and its success or otherwise in meeting pre-determined criteria for minimising environmental impact. Consider providing a written report to senior management on rehabilitation - any issues arising or lessons learned for future work in the same or similar environments. 3.

A conical concrete plug with a metal bolt, first designed and used at WMC Limited's Kalgoorlie Nickel Operations. It forms an invisible permanent cap, but also allows the hole to be found and reopened if need be.

4.1.2. GUIDELINES FOR THE PREPARATION OF AN ENVIRONMENTAL 1 IMPACT STATEMENT 1. INTRODUCTION Community expectations in Australia for the protection and preservation of the environment have resulted in the past two decades in legislative and administrative measures which take into consideration both society’s demands for supply of essential raw materials, and the community’s aspirations for a clean, healthy and pleasant environment. The Commonwealth and State Governments have legislated widely in the fields of conservation and protection of the environment. The Commonwealth and all States now have established procedures for the environmental assessment of development proposals. The various Mining Acts also contain procedures for environmental protection. In general, mining activities authorised under the provisions of mining legislation may only be carried out in accordance with predetermined operating conditions including conditions for prevention of pollution and protection of the environment. Holders of mining titles are also bound by the other environmental legislation referred to above. While the assessment of the environmental impact of mining activities generally is carried out by specialist consultants, the early appreciation of potential problems can simplify their solution. The following guidelines do not have the approval of any of the State authorities. They are intended as a broad indication of the areas of probable environmental significance, and are not intended to replace consultation with Government authorities, both Local and State. Such consultation is now an

80

essential preliminary to detailed exploration and is invariably required prior to an environmental impact study which in turn is one of the required stages in mine-site development.

2. SPECIFIED ACTIVITIES The type of activity which may necessitate environmental investigation varies from State to State. As activities develop from preliminary exploration to detailed engineering and project planning the level of environmental information required to assess impacts and enable environmental controls to be implemented, progressively increases. Detailed guidelines for preservation of the environment during mineral exploration are provided in Section 4.1.1. The following stages provide an indication of the level of information and consultation required:

1.

Prepared by consulting engineers Dames and Moore Pty Ltd, Sydney, incorporating advice from BMR and the State Geological Surveys.

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Preliminary prospecting exploration

b.

Consideration of prudent and feasible alternatives including the no-project option.

c.

Statutory requirements.

• reconnaissance surveys of land, soils, hydrology, biology, archaeological and cultural aspects;

• assess possible effects of clearing, road location etc, and take action to minimise environmental damage;

• initiate

2. Description of the existing environment a.

Topography.

b.

• establish and maintain liaison with local residents.

Regional geology and geology of the ore deposit (including the mineralogy and geochemistry).

c.

Soils and erosion, land capability.

Detailed prospecting exploration

d.

Flora and fauna and habitat analysis.

• extend and upgrade the above surveys and extend

e.

Landscape and visual aspects.

f.

Hydrology–catchments, streams, other water bodies, downstream uses (surface and ground-water), background water quality.

g.

Aboriginal archaeology and anthropology, heritage and conservation aspects.

h.

Natural characteristics of the area.

i

Land ownership, land use, land zoning and/or policies.

j.

Background noise levels.

k.

Local and regional climatic meteorology and air quality.

l.

Cultural, social and socio-economic aspects.

consultations with all appropriate Government Authorities on environmental requirements; and

to include social and socioeconomic aspects;

• establish base-line monitoring programmes for air quality, water quality, meteorology and hydrology;

• maintain

consultations with Government Authorities and request guidelines for possible Environmental Impact Statement (EIS) or equivalent document to enable base-line information to be collected; and

• maintain contact with local residents and extend to the broader local community including local groups and authorities. Project planning and feasibility studies

• undertake comprehensive investigation of natural and physical environment and social and socioeconomic aspects to provide basic information for EIS;

3. Specific features a.

Unusual vegetation communities.

b.

Rare or endangered flora species.

c.

Rare or significant faunal occurrences and habitats.

d.

Aquatic biology.

e.

Caves or other significant geological formations.

f.

Aboriginal sites or relics or heritage.

g.

Sites of historical significance.

h.

Use for recreation and tourism.

i.

Existing resource utilisation (agriculture, forestry, etc).

• analyse the results of monitoring programmes and supplement where necessary;

• maintain consultations with Authorities and obtain final guidelines for EIS and definition of other legislative and regulatory requirements;

• maintain contact with the community and conduct community studies for inclusion in EIS; and

• prepare EIS for public release. 3. CONTENTS OF AN ENVIRONMENTAL IMPACT STATEMENT (EIS) The requirements for the contents and format of the EIS vary from State to State and with the type and size of the proposed mining development. However a general listing of contents can be used as a checklist on the basis of which the appropriate sections can be completed.

a. b.

General description of the proposed development stating its need and objectives and the proponents of the project and including its location, preferably with photographs of the site.

Field Geologists’ Manual

or

other

plant

4. Detailed description of the proposal

1. Executive summary a.

types

c. d.

Prospecting methods and results used to define mineable ore. Estimates of the available resource (eg tonnage, grade) and extent of mineralisation. Proposed methods of extraction. Rate of production of each metal, mineral or concentrate.

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MINING AND ECONOMIC GEOLOGY

e.

f. g. h.

Quantity of waste rock, shaft spoil, or overburden to be excavated and methods of handling and disposal, both as total quantities and rates of production. Type of machinery and equipment to be used. Type of metallurgical processes and chemicals etc to be used. If open cut methods to be used:

Methods of extraction.

b.

Siting of headworks, processing plants, waste disposal areas.

c.

Transport options

6. Assessment of impacts and safeguards to prevent or minimise impacts

Total surface area to be excavated (in hectares);

a. b.

Control of runoff and erosion.

ii.

The typical dimensions of cuts, trenches or pits (including depth); and

c.

Prevention of water pollution and water treatment methods.

iii. The area (in hectares) of land to be under open cut rehabilitation at any one time.

d.

Anticipated noise levels from extraction, milling and haulage operations and attenuation procedures.

e.

Disposal of waste material and overburden.

f.

Impacts on nearby residents or communities both social and socioeconomic and on local infrastructure and services.

g.

Effects on areas of cultural, historical, recreational, scientific, social, aesthetic or conservation significance.

h.

Effects on local ecosystems, flora and fauna.

i.

Effects on other land uses.

j.

Impacts on local roads, transportation etc.

Expected life of operation.

j.

Number of persons to be employed and their likely places of residence.

k.

Hours of operation.

1.

Sources of quantities of processing and potable water required.

m.

Detailed water balance.

n.

Transport of product from mine, frequency of trucking and traffic movements and their routes, internal and external roads required. Current market trends and industry demand for product.

p.

Drainage, expected sub-surface water interactions, and water pollution controls.

q.

Methods for sewage disposal.

r.

Quantity of mine spoil and mill tailings and methods of handling these.

flow

s.

Buildings and plant to be erected.

t.

Blasting methods and times.

u.

Rehabilitation procedures, during and on completion of extraction and mining operation:

82

a.

i.

i.

o.

5. Consideration of alternatives

i.

regrading and of site;

ii.

removal of buildings and structures;

Visual impact, dust, odours and air pollution.

7. The document should include as a minimum the following two plans: (a)

     

Locality plan at a suitable regional scale (eg 1:25 000) showing: boundary of the proposed mining lease; contours at 10 m intervals or less; rivers, creeks and other waterbodies ; towns and villages; roads; and land tenure; particularly crown land such as state forest, national parks, local government boundaries, planning scheme zonings, agricultural land, other land use constraints.

iii. topsoil handling and storage;

(b)

Mining plan at a (eg 1:2000) showing:

suitably

detailed

scale

iv.

revegation procedures and species to be used;

v.

fertilising, watering, maintenance; and

vi.

economic benefits of the project to proponent, local community, State and Nation.

 boundary of the mining lease;  areas to be mined;  location of each open cut, strip or pit and the sequence of extraction;

 location of shafts, adits, headframes;  overburden, waste rock, shaft spoil disposal areas;

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MINING AND ECONOMIC GEOLOGY

    

mill tailings disposal areas; ore stockpile areas; topsoil stockpile areas; location of plant, machinery, buildings; internal formed roads;

    

water supply dams; sediment control dams; drainage channels or other runoff control methods; vegetation communities of the lease area; and location of nearest residences.

4.2. FIELD CHEMICAL TESTS FOR COMMON ELEMENTS AND MINERAL CLASSES FLAME TESTS Aluminium (hydrated oxides as in bauxite; for corundum, sapphire, etc, see Gemstones)

OTHER CHARACTERISTICS 1.

Loss on ignition of 34.6 per cent (gibbsite), 15 per cent (diaspore, boehmite).

2.

From solutions of aluminium salts, the addition of ammonia or sodium hydroxide will precipitate white gelatinous aluminium hydroxide.

1.

Roast the mineral, then dissolve by boiling in excess concentrated hydrochloric acid. Dilution with water, or addition of sodium hydroxide, produces a white precipitate.

Arsenic (sulphides) 1. Garlic odour and distinct white coating when heated on charcoal.

1.

Barely soluble in concentrated hydrochloric acid.

2.

2.

Soluble in sodium hydroxide, and in ammonia.

3.

Soluble in hot concentrated nitric acid.

Asbestos 1. Incombustible, low conductivity of heat.

1.

Fibrous habit distinctive.

Barium (carbonate, sulphate) 1. Colours a flame yellowish green.

1.

Sulphate insoluble in acids, high density (’heavyspar’) distinctive.

2.

Carbonate soluble in dilute hydrochloric acid; this solution, after further dilution, gives a white precipitate with dilute sulphuric acid.

1.

Insoluble in common acids.

2.

Hardness and hexagonal prism form distinctive.

3.

Pulverise a pea-sized fragment and fuse in a test tube with potassium hydroxide. Cool and dilute with water, producing a clear solution.

Antimony (metal, sulphides) 1. Dense white fumes are emitted and a white sublimate remains on charcoal block after heating with a blowpipe. 2.

In a closed tube, heating the sulphides gives a hot black sublimate which is reddish brown when cold.

3.

Produces a dull blue colour in the reducing flame.

4.

May be reduced with sodium carbonate on a charcoal block to brittle white metallic beads.

This coating, and arsenic minerals generally, give a blue colour in the reducing flame.

Beryllium (beryl, emerald) 1. Unaffected by moderate temperatures.

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FLAME TESTS

OTHER CHARACTERISTICS

Beryllium (cont)

Dissolve a pea-sized fragment of potassium hydroxide in a test tube full of water, add a few crystals of quinalizarin to produce a reddish purple solution. If this indicator solution is added in equal volume to the clear solution above, the indicator immediately turns pale blue.

Bismuth (metal, oxide, carbonate, sulphide) 1. Very easily fusible.

1.

Heat the powdered mineral on a metal plate; white fumes ( BiO3 ) will evolve. These will condense on any cool surface.

1.

Soluble in water.

Cadmium (sulphide, oxide) 1. Sublimate on charcoal block is reddish brown in the centre and various orange and yellow colours on the margins.

1.

When sodium hydroxide is added to cadmium nitrate, a white precipitate is formed.

Calcium (fluoride, sulphate, carbonates) 1. Flame colour, after moistening hydrochloric acid is red or yellowish red.

1.

Concentrated sulphuric acid gives a white precipitate, which is soluble in hot water.

2.

Heating on a charcoal block produces a crust which is orange-yellow when hot, and lemon-yellow when cold.

3.

Reduction on a charcoal block with sodium carbonate produces brittle white beads of metallic bismuth.

Boron (borax) 1. Very easily fusible to a colourless bead. 2.

Gives a bright green flame colour.

with

Carbonates*

From: Reid, W P, 1969. Mineral Staining Tests. Colo Sch. Mines, Mineral Industries Bulletin, 12 (3), by permission. * A simple procedure for identifying calcite, ferroan calcite, ferroan dolomite (ankerite) and rhodochrosite is provided in Hitzman, M W, 1999. Routine staining of drill core to determine carbonate mineralogy and distinguish carbonate alteration textures, Mineralium Deposita, 34:794-798.

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FLAME TESTS Chromium (oxides) 1. Borax bead is green, and the sodium carbonate bead is yellow.

Clay 1. Infusible, often decrepitates with loss of water.

OTHER CHARACTERISTICS 1.

Concentrated sulphuric acid gives a yellow solution, which turns green on the addition of alcohol.

2.

Chromite sands are distinguished from magnetite grains by their brown streak and feeble magnetic properties.

1.

Identified by soft, sometimes greasy feel and low density. Differentiated by X-ray diffraction methods and differential thermal analysis. Montmorillonite is stained blue by spraying on a benzidene in water solution.

2. 3. Cobalt (sulphides, arsenides) 1. Borax bead is blue, both hot and cold, in both the oxidising and reducing flame. 2.

1.

After roasting, dissolve in nitric acid: (a) Sodium hydroxide produces a blue precipitate, which becomes reddish on boiling.

Reduction on charcoal with sodium carbonate produces a grey to black magnetic powder.

(b) Ammonia produces a blue precipitate, soluble in excess, and the solution rapidly turns brown. 2.

On fusion with potassium hydroxide and cooling, a bright blue glass results.

1.

After boiling in aqua regia, the filtered solution is diluted with water. Addition of ammonia will give a dense reddish-brown gel if ample iron is present (chalcopyrite), then a pale blue colour will be seen as the gel settles. In dilute acid solution, metallic iron or zinc is coated with copper metal. Rubeanic acid (Dithio-oxamide) in benzol solution is coloured black by traces of copper in weakly acid solution. Chalcopyrite can be distinguished from pyrite by its lower hardness, greenish black streak and easier fusibility. Use copper-sensitive paint. Mix 40 g ammonium molybdate, 20 g sodium pyrophosphate and 170 g titanium dioxide in 200 ml of 50 per cent hydrochloric acid. Apply with a brush to a clean rock surface, and specks of blue colour will appear on copper sulphide minerals within 30-60 seconds. The paint liberates H2S from sulphides which reduces molybdate ions to molybdenum blue. Note that blue specks will appear on pyrite after about four minutes, and the paint deteriorates with time, becoming ineffective after about ten days. Oxide copper minerals are not detected1.

Columbium and Tantalum (see Niobium) Copper (oxides, carbonates, sulphides) 1. Flame colour is green, and (after moistening with hydrochloric acid) azure blue. 2.

A mixture of copper minerals and sodium carbonate can be reduced on a charcoal block to malleable red beads of metallic copper.

3.

The borax bead is green in the oxidising flame, and blue when cold. In the reducing flame, the bead is reddish-brown when saturated with copper.

2. 3.

4.

5.

1.

From Annels, A E, 1991. Mineral Deposit Evaluation, pp 81-82 (Chapman Hall: London).

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FLAME TESTS

OTHER CHARACTERISTICS

Diamond 1. Infusible, burns at +1000ºC.

1.

Distinguished by high density and hardness; unaffected by concentrated acids and alkalis. Ability to scratch corundum is definitive.

1.

Sodium cobaltinitrite in aqueous solution gives a yellow stain with potassium feldspar and other potassium minerals. Etch the rock surface with hydrofluoric acid, then add sodium cobaltinitrite solution (a saturated solution of about 200 g per litre of distilled water, including a few drops of acetic acid per litre). Note that hydrofluoric acid is extremely corrosive and use has led to fatalities.

2.

The calcium rich plagioclases are soluble in concentrated hydrochloric acid, with separation of gelatinous silica.

3.

With the quinalizarin test for beryl (q.v.), the indicator solution does not change colour.

1.

Distinguished by high density and hardness.

1.

The native metal is distinguished by its high density, malleability and lustre.

2.

Boil in aqua-regia, add metallic tin, giving a purple precipitate (purple of Cassius).

3.

For gold tellurides, see Tellurium.

1.

Acid solutions are green, from which ammonia produces a reddish-brown gelatinous precipitate, or sodium hydroxide produces a reddish-brown precipitate.

with

1.

Reduction with sodium carbonate on a char-coal block produces malleable white beads of metallic lead, and a yellow coating on the charcoal nearby.

After moistening with 50 per cent nitric acid solution, and spraying on an aqueous solution of 20 per cent potassium iodide, a yellow precipitate will form. This precipitate is readily soluble in hot water.

2.

Boil the lead mineral in 50 per cent nitric acid, then add a few mls of hydrochloric acid. The dense white precipitate (PbCl2) is soluble in hot water.

Feldspars 1. The potassium feldspars are fusible at high temperatures, and do not colour the flame. When mixed with gypsum and heated on charcoal with a blowpipe, give a violet flame. 2.

The plagioclases are more easily fused, with the sodium rich members giving a deep yellow flame colour.

Gemstones (sapphire and ruby; for emerald see Beryllium) 1. Unaltered by blowpipe flame, or on heating with sodium carbonate on charcoal. Gold (metal, alloys)

Iron (oxides, sulphides) 1. When reduced on charcoal alone, or with sodium carbonate, a grey to black magnetic powder or bead is produced. 2.

The borax bead formed in the oxidising flame is yellow when hot, and pale yellow or white when cold. The reducing flame bead is pale green.

Lead (oxides, sulphides) 1. Flame colour (after moistening hydrochloric acid) is a dull blue. 2.

Lithium (silicates, micas) 1. Flame colour is intense carmine red. 2.

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Easily fusible, producing a glass sphere.

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FLAME TESTS Magnesium (oxide, carbonates) 1. Heating on a charcoal block leaves a white residue. If this is moistened with cobalt nitrate, and reheated, a pink colour results from most magnesium minerals. Manganese (oxides) 1. Borax bead, with trace manganese concentration, is amethyst colour in the oxidising flame, and colourless in the reducing flame. Beads with excess manganese are dark red to black in the oxidising flame. The sodium carbonate bead, formed in the oxidising flame, is green. 2.

OTHER CHARACTERISTICS 1.

Secondary magnesite adheres to the tongue.

2.

Dissolve in aqua-regia, add excess ammonia, filter off any precipitates. Add to the remaining solution a little sodium phosphate, which will produce a white precipitate.

1.

Most manganese minerals dissolve in hydrochloric acid, with the evolution of yellowish-green chlorine gas. Fusion with potassium hydroxide gives a brilliant green melt.

2.

Manganese chloride colours the flame pale green.

Mercury (sulphide) 1. When heated with sodium carbonate in a test tube, a film of metallic mercury is deposited (’mirror of mercury’).

1.

Dissolve in aqua-regia; this solution will deposit mercury on a copper coin.

Molybdenum (oxide, sulphide, molybdates) 1. Borax bead in the oxidising flame is yellow when hot and clear when cold. In the reducing flame the bead is dark brown both hot and cold.

1.

Molybdenite is distinguished by its habit, of soft radiating plates, with low density. Molybdates (powellite and wulfenite), when dissolved in hydrochloric acid, provide after the addition of metallic tin, a solution which is first green then blue, and finally brown.

Nickel (silicates, sulphides) 1. The borax bead, in the oxidising flame, is violet when hot and brown when cold. In the reducing flame, the bead with trace nickel is colourless, and opaque grey with high nickel content. 2.

2.

1.

Dissolve mineral in boiling aqua-regia, dilute with cold water. Addition of ammonia produces a green precipitate. Add to the filtered liquid a few drops of dimethylglyoxime solution (ten per cent solution in alcohol)—a brilliant red precipitate indicates nickel.

1.

Pulverise a pea-sized fragment of pure mineral, and fuse this with an equal amount of potassium hydroxide. Add an equal volume of concentrated hydrochloric acid and boil gently for 30 seconds, then add a few grams of metallic tin. Continue to warm the solution, and if it remains colourless, dilute with an equal volume of water. If the solution is blue, niobium is indicated. With further dilution or heating the solution becomes colourless again, and a white precipitate is formed, on standing. Distinguished from other dark minerals by high density and prismatic forms.

Reduction on charcoal with sodium carbonate produces a grey to black magnetic bead.

Niobium (Columbium) and Tantalum (columbite-tantalite)

2. Phosphates 1. Flame colour after moistening with sulphuric acid is pale green.

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1.

Spray on 50 per cent nitric acid, after a minute or so spray on ammonium molybdate (ten per cent aqueous solution). A yellow precipitate indicates phosphorus. 87

MINING AND ECONOMIC GEOLOGY

FLAME TESTS

OTHER CHARACTERISTICS

Phosphates (cont.)

Platinoids (platinum, palladium, osmium, iridium metals and alloys)

2.

A sensitive phosphate staining test suitable for reasonably smooth rock surfaces is described in Morris, R C, 1974. A pilot study of phosphorus distribution in parts of the Brockman Iron Formation, Hamersley Group, Western Australia, Geol. Surv. West. Aust. Annu. Rep., 1973, pp 77-78.

1.

Distinguished by high density, colour and lustre, and malleability. Palladium is soluble in nitric acid, platinum and palladium are soluble in hot aqua regia, while osmium and iridium are insoluble.

2.

Potassium (see Feldspars) Silver (metal, alloys, oxides, salts, sulphides) 1. Reducible to malleable white beads of metallic silver by heating on a charcoal block with sodium carbonate.

1.

Digest in hot 50 per cent nitric acid, and allow to cool. Add a few mls of hydrochloric acid, which will precipitate white AgCl (see Lead test) which is insoluble in water but soluble in ammonia. The AgCl precipitate darkens with exposure to sunlight.

1.

Boiling with concentrated hydrochloric acid causes the emission of pungent hydrogen sulphide gas.

1.

Tellurides dissolve in warm concentrated sulphuric acid to produce a deep red solution.

1.

Place the mineral grains in hydrochloric acid with metallic zinc, or pour the grains and acid into a zinc dish. The grains are coated with a grey layer of metallic tin, which (in larger pieces) may be polished with a cloth to a brilliant tin plating.

1.

Fuse powdered unknown with potassium hydroxide, then boil in concentrated hydrochloric acid. After prolonged boiling, the solution will turn a delicate lilac colour.

Sodium 1. Flame colour is intense yellow. Strontium (carbonate, sulphate) 1. Crimson flame after hydrochloric acid.

moistening

with

Sulphides 1. Roasting on charcoal gives SO2 gas. 2.

Sulphides and sulphates produce sodium sulphide by roasting with sodium carbonate on charcoal. When the fused mass is moistened and placed on a silver coin, a black or yellow stain of silver sulphide is produced.

Tantalum (see Niobium) Tellurium (natural alloys) 1. Heating in an open tube produces a sublimate of white to yellowish droplets. 2. On a charcoal block a white to grey sublimate is formed, which colours the reducing flame green. Tin (oxide, complex sulphides) 1. Reduction on a charcoal block with sodium carbonate produces fine white malleable beads of metallic tin and a white sublimate.

Titanium (oxides) 1. The borax bead is colourless in the oxidising flame. In the reducing flame the bead is first yellow, becoming dark blue with prolonged heating. 88

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FLAME TESTS

OTHER CHARACTERISTICS

Titanium (cont.)

After cooling, the presence of titanium can be confirmed by adding hydrogen peroxide, which produces a bright orange colour.

Tungsten (tungstates) 1. The borax bead with trace tungsten is colourless; those with high tungsten content are yellow when hot and colourless when cold.

1.

Pulverise a pea-sized fragment of pure mineral, and fuse this with potassium hydroxide. After cooling, the fused mass will be green if manganese is present. Boil the mass in concentrated hydrochloric acid, add a little metallic tin, which immediately gives a blue solution if tungsten is present.

Uranium (oxides, uranates) 1. Borax bead is yellow in the oxidising flame, and green in the reducing flame.

1.

All naturally occurring uranium minerals, when in equilibrium, are radio-active. Some secondary uranium minerals are fluorescent.

2. Vanadium (sulphide, vanadates) 1. The oxidising flame borax bead is yellow when hot, and greenish-yellow when cold. The reducing flame bead is brown when hot, and clear green when cold.

1.

2.

Zinc (oxides, carbonates) 1. With the reducing flame on a charcoal block, zinc minerals give a powder which is yellow when hot and white when cold. After moistening with cobalt nitrate and reheating in the oxidising flame, most zinc compounds give a green colour, but hemimorphite gives a blue colour.

Zirconium (silicate) 1. Infusible, coloured varieties change colour to white or colourless

1.

2.

1.

2. Further information on field chemical tests is available from: 1.

Barefoot, R R and Van Loon, J C, 1993. Analytical methods: field and remote locations, in Analysis of Geological Materials (Ed: C Riddle), pp 221-261 (Marcel Dekker: New York).

Field Geologists’ Manual

Pour concentrated hydrochloric acid on to the dry mineral, when chlorine will evolve and the solution turns a deep red colour. Diluting this solution with water produces a pale green, then practically clear colour. Boil the dry mineral in concentrated sulphuric acid for a few minutes and allow to cool. The addition of cold water will change the solution colour to green. On fusion with potassium hydroxide, the fused mass is reddish-orange at the bottom and yellow on top. If a small amount of cobalt nitrate is added during fusion, the melt will be apple green. The ‘zinc zap’ test. Prepare solution A by dissolving 9 mL of conc. hydrochloric acid, 30 g of oxalic acid and 5 mL of diethylaniline in one litre of distilled water; and prepare solution B by dissolving 30 g of potassium ferricyanide in one litre of distilled water. Mix equal parts of solutions A and B and apply to the specimen; gives a bright reddish brown colour with zinc. Solutions A and B have a shelf life of about three months, but when mixed will deteriorate after about a week. Decomposed by fusion with sodium carbonate. Generally insoluble in acids, with slight solubility of the pulverised mineral in concentrated sulphuric acid. Distinguished by high density and hardness, and crystal form.

2.

Feigl, F and Anger, V, 1972. Spot Tests in Inorganic th Analysis, 6 ed (Elsevier: New York).

3.

Jungreis, E, 1985. Spot Test Analysis (John Wiley: New York).

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4.3. COMMERCIAL FACTORS FOR COMMON ORES

1

The common ores discussed herein are classified by their end use or product, these being: Aluminium

Fluorite

Platinum group

Antimony

Gemstones

Rare earths and thorium

Arsenic

Gold

Rhenium

Asbestos

Hafnium

Rubidium

Barium and barite

Indium

Selenium

Beryllium

Industrial minerals

Silica

Bismuth

Iron

Sodium

Boron

Lead, zinc and silver

Sulphur

Cadmium, gallium, germanium and indium

Lithium

Talc, steatite and pyrophyllite

Caesium

Magnesium (dolomite and magnesite)

Tellurium

Calcium (gypsum and limestone)

Manganese

Thallium

Chromite

Mercury

Tin

Clays

Mica and vermiculite

Titanium and zirconium

Coal

Molybdenum

Tungsten

Cobalt

Nickel

Uranium

Copper

Niobium (columbium) and tantalum

Vanadium

Diamonds

Phosphate

INTRODUCTION Ore is commonly defined as any naturally occurring mineral substance that might be mined and sold at a profit. However, many commercial factors determine whether a mineral occurrence constitutes ore. These include demand for the particular metal or non-metallic substance, price at the point of sale, the size and location of the deposit, cost of metallurgical treatment, losses incurred in mining and upgrading the material to a saleable product, and the presence of undesirable impurities. Many buyers of finished or semi-finished mineral products set tight specifications on quality. Woodcock and Hamilton (1993) is the standard Australian reference to these specifications and to ore treatment methods generally. It is common practice, among inexperienced mineral exploration geologists, to multiply the average grade for a particular deposit by the London Metal Exchange (LME) price for those metals, and thus arrive at a ‘value per tonne’ for the deposit. The calculation is often done mentally, and assumes 100 per cent recovery for all the metals present, and that the LME price is paid for all the metals. These estimates are quite misleading, as they ignore all the probable losses in mining and treatment, and a wide range of commercial factors. As an example, Lewis (1993) advises that the net smelter return for copper concentrates is 70-80 per cent of the contained metal, 45-65 per cent for lead, about 60 per cent for nickel and 40-60 per cent for zinc. Goldie and Tredger (1993) provide

1.

90

Revised with assistance from geoscientists of the AGSO Mineral Resources and Energy program and consulting metallurgist J T Woodcock.

examples of net smelter returns for Canadian mines. The definitions of Ore Reserves in the JORC Code (section 4.5 herein) incorporate these factors. Many mineral products, particularly those sold in bulk such as coal, iron ore and bauxite, are largely traded on a long term contract basis or to captive markets. For the metals, concentrates and ores that are commonly sold on the open market as a finished product, or to a smelter or refiner, the price paid is normally based on the LME quotations. These are published in such journals as London Metal Bulletin, Metals Week, Industrial Minerals and Minerals Price Watch (the last with web address http://www.mineralnet.co.uk). Some of these commercial factors are discussed in the following paragraphs, particularly as they apply to Australia. These are largely based on personal experience, with assistance from the Australian mining industry. Production statistics were taken from the USGS World Mineral Commodity Summaries (1999) and from Mining Annual Review (1998). Sales on the LME are in £sterling or $US per tonne except for precious metals, which are quoted in $US per troy ounce. Sales in the US are quoted in dollars or cents (US) per pound for base metals, but ore and concentrate prices may be stated for tonnes, long tons, or short tons.

ALUMINIUM Estimated world production of newly smelted aluminium was about 19 million tonnes in 1997. Practically all of this was derived from bauxite, using the Bayer sodium hydroxide digestion process to form alumina, which is then smelted by the Hall-Heroult

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MINING AND ECONOMIC GEOLOGY

electrolytic method (Nixon, 1987) to provide chemically pure metal. There is minor aluminium production from other aluminous raw materials using acid leaching, in areas of special logistic circumstances, of which mining of alunite in Azerbaijan and nepheline syenite in Russia are the main examples (Crowson, 1996, p 4). Total world production of bauxite in 1997 was about 125 million tonnes. About 95 per cent of the bauxite mined is converted to alumina, and 90 per cent of the alumina is smelted to aluminium. The remaining five per cent of the bauxite produced is mainly used as refractories, as calcined bauxite, and the remaining ten per cent of the alumina is used in chemical applications, largely for water treatment and in abrasives, as fused alumina. The term bauxite is used for naturally occurring mixtures of aluminium monohydrate (boehmite or diaspore, AlO.OH) and trihydrate (gibbsite, Al(OH)3), including impurities which are typically clay minerals, free silica, iron hydroxides and titania. The Weipa bauxite is beneficiated by simple wet screening, discarding the fine clay and silica fraction; other Australian bauxites are shipped as mined. Ore grade parameters, for the beneficiated products, are generally loss on ignition (at 1000 to 1200°C) after drying at 100 to 110°C, total per cent Fe2O3, total per cent SiO2, total per cent TiO2, and some special Bayer process variables, viz: Total alumina or total chemical alumina (TCA), which comprises alumina present as trihydrate, monohydrate and in clay minerals, and is determined by chemical analysis. Total available alumina (TAA), the alumina present as monohydrate and trihydrate, and some clays, which is determined by bomb (autoclave) digestion of the sample by caustic soda at greater than 180°C. Trihydrate alumina (THA) is determined by bomb digestion at 140°C or less, whereby only gibbsite and kaolin-family clay minerals are soluble in caustic soda. Reactive silica is that which reacts with caustic soda at a specified temperature. Below 140°C only the silica in clay minerals is soluble in caustic soda, whereas above 180°C all or part of the free quartz present is attacked. In 1997 Australia produced about 44.5 million tonnes of bauxite, with average grades as shown in Table 1, and 13.4 million tonnes of alumina. Production from Weipa in 1997 included 136 000 tonnes of abrasive grade calcined bauxite, of average grade 83-86 per cent total Al2O3, and five to six per cent reactive silica; world demand for calcined bauxite is 400 000 to 500 000 tonnes per year. The Kwinana (Alcoa) plant produces about 160 000 tonnes per year of chemical grade alumina, which is used in the water purification, ceramic and paper industries. World demand for chemical grade alumina is about two million tonnes per year.

Field Geologists’ Manual

TABLE 1 Average bauxite grades from the three major Australian mining areas Area

Total Al2O3, Avail. Al2O3, % %

Reactive silica, %

Weipa

54-56

49-51

Gove

50

46

4

30-44

30-35

1-2

Darling Ra.

5-6

Major alumina plant requirements are power, water and caustic soda (imported from Japan and the USA). Disposal of ‘red mud’, the reject clays and iron oxides, is invariably a problem. Electrolytic smelting consumes about 0.25 tonne of petroleum coke electrodes, about 17 000 kWh of electricity and minor cryolite (usually made on site from sodium carbonate, fluorite and bauxite) per tonne of metal produced. Specifications for non-metallurgical bauxite and alumina are provided in Griffith (1996, p 17). Australian bauxite is refined in integrated alumina plants or sold on the open market. There are open market quotes for calcined bauxite and chemical grade alumina.

ANTIMONY Estimated world mine production of antimony in ores and concentrates was about 140 000 tonnes in 1997. China was the largest producer, with more than 75 per cent of the world market. The principal ore mineral is stibnite (Sb2S3), which is often won as a byproduct of polymetallic gold and lead ores. The Australian demand is satisfied by antimony recovered in smelting lead concentrates (Broken Hill lead concentrates contain 0.1-0.2 per cent antimony), and by imports of antimony metal and concentrate. Production from the Hillgrove (NSW) antimony lodes for 1997 was 55 683 tonnes of ore of head grade 2.03 per cent Sb and 4.4 g/t Au. Treatment by gravity and flotation produced 3397 tonnes of concentrate containing 2218 tonnes of antimony and 9140 ounces of gold. Concentrate sales (with minimum grade 55 per cent Sb) are quoted in $US per long ton unit, ie, per one per cent antimony per ton of concentrates. Maximum allowable impurity levels in concentrates are 5 ppm mercury and one per cent total lead plus arsenic. Smelters generally pay for gold contained in antimony concentrate, after substantial deductions that may result in no payment for the gold content. The antimony market is notoriously erratic.

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MINING AND ECONOMIC GEOLOGY

ARSENIC Estimated world production of arsenic trioxide (As2O3, containing 76 per cent As) was around 42 000 tonnes in 1998. The major ore mineral is arsenopyrite (FeAsS), with enargite (Cu3AsS4) a minor source. The demand is easily supplied as a byproduct from roasting lead, copper and gold concentrates containing arsenic sulphides, by which the arsenious oxide is collected as smelter dusts and condensates. The impure oxide is purified by sublimation in iron pots, producing arsenic or white arsenic as pure As2O3. Sales are at a minimum 95 per cent As2O3, content, quoted in $US per pound, but users prefer a minimum grade of 99.5 per cent As2O3.

ASBESTOS World production of all types of asbestos was about 1.95 million tonnes in 1998, with Russia, Canada, China and Brazil the major sources. Demand diminishes each year, as more environmentally acceptable substitutes are found. There is no current asbestos production in Australia. The only significant Australian asbestos miner in recent years was Woodsreef Mines Ltd. Production in 1980 was 9.5 million tonnes of waste and 3.148 million tonnes of ore which was crushed to yield 83 466 tonnes of fibre. The mine was marginally profitable at best. The term asbestos is commercial rather than mineralogical. It is applied to varieties of several minerals that are characterised by a very fibrous habit and a well-developed prismatic cleavage, so that thin flexible fibres are obtainable. The principal asbestos minerals are listed in Table 2. The grade of asbestos deposits is quoted as per cent fibre, this being determined in the exploration stage by counting individual vein widths over a standard interval of drill core or costean exposure (Butt, 1971). The value of a deposit can only be determined by treatment of a bulk sample to separate the asbestos product. Critical parameters are the degree of separation of the fibre mass into individual fibres (crudity), fibre length and strength, colour (white being preferred) and magnetic properties. World standards for asbestos products are determined by the Quebec Asbestos Mining Association. Ore treatment usually entails separation by screening after primary, secondary and impact crushing, discarding rock fragments of >3 cm diameter, as these are generally lower than average grade. The remaining rock is then fiberised and the lighter asbestos minerals removed by elutriation (the industry refers to it as aspiration). The asbestos is then cleaned, to remove grit and dust, and graded by screening into one of nine groups, ranging from groups one and two (uniformly long fibre, generally obtained from hand cobbed ore), to group seven, refuse and shorts, and groups eight and nine (sand and gravel), and many subgroups.

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These groups do not contain a uniform fibre length but varying proportions of fibre of different lengths, ie group four has a higher proportion of long fibre, plus 14 mesh, than group five, and so on. TABLE 2 Principal asbestos minerals1. Mineral

Properties of good quality fibre

Chrysotile (white asbestos)

White, flexible, high tensile strength, and particularly suitable for spinning. Poor resistance to acids and alkalis, good heat resistance, but becomes brittle at high temperatures.

Crocidolite (blue asbestos, a fibrous variety of riebeckite

Blue, long fibres, high tensile strength. Resistant to acids and alkalis, but poor heat resistance. Has fair spinning properties.

Amosite

White, long and flexible fibres that are coarse and not readily spinnable. Good resistance to acid, alkalis and heat, but becomes brittle at high temperature.

Anthophyllite

Brittle, short fibres with low tensile strength. Very good resistance to acids, alkalis and heat.

Tremolite

Brittle and generally short fibres with low tensile strength. Fair to good resistance to acids, alkalis and heat.

Actinolite

1.

From McLeod (1965), p. 49.

The bulk of world production is of short fibre material, largely groups four, five and six, which have a fibre length less than 1 cm. Prices are quoted in $ Canadian per short ton, with a very wide price range (largely dependent on fibre length and the content of minus 200 mesh material) and with a considerable premium for long fibre groups. Asbestos is being replaced by other materials in many of its historic applications due to associated health problems.

BARIUM AND BARITE The principal barium mineral is barite (also known as barytes or heavyspar, BaSO4). World production of barite was around 6.2 million tonnes in 1998, and 60-70 per cent of this was consumed as a weighting filler in high-density muds used in drilling oil and gas wells.

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Consumption in the Australasian region is probably around 250 000 tonnes per year. The industrial (non-drilling) market is divided fairly evenly between glass, paint, rubber and various other industrial applications where the high density and low absorptive characteristics of the material make it valuable. Ore deposits are generally massive deposits of high purity (>90 per cent barite), which are selectively mined to minimise dilution with wall rock. It is generally uneconomic to provide a barite concentrate of saleable grade from gangue material in barite-base metal ores. Only those deposits that are reasonably close to transport and are simply mined, and have an adequate water supply, are of interest. Processing is normally crushing, followed by upgrading which may involve heavy medium separation, jigging and tabling, then drying, dry milling, and air classification. In some cases colour selection, either mechanical or manual, may replace the metallurgical stage. Typical concentrate grades are shown in Table 3. TABLE 3 Typical barite concentrate specifications. Component

Oil drilling grade

1

Industrial grade

2

BaSO4 content, %

Min. 90

Variable, >80

Impurities

Min. soluble salts that would affect pH, max. 250 ppm Ca

Min. Fe, prefer <500 ppm

Particle size

About 99% <200 BSS

Variable, 200-400 BSS

Density

Min. 4.2

>4.25

Colour

-

Pure white

1.

Barite used in drilling mud should meet American Petroleum Institute Specification 13A, Specifications for Drilling Fluid Materials, 1993.

2.

Require max. 40 ppm Mn for the rubber industry.

Sale prices for all barite grades are quoted in $US per tonne in bulk shipments, with higher prices for ground or bagged product.

BERYLLIUM Total production in 1997 was about 210 tonnes of contained beryllium, and known reserves are adequate for hundreds of years of production. The major commercial ore minerals are bertrandite [Be4Si2O7(OH)2] with max. 42 per cent BeO, and beryl (Be3Al2Si2O18) with a maximum of about 14 per cent BeO. About 95 per cent of the world’s beryllium is provided by bertrandite from the Brush Wellman company operations in the Spur Mountain area of Utah. The Thor Lake phenacite (Be2SiO4) deposit in the NW Territories of Canada, with a resource of 550 000

Field Geologists’ Manual

tonnes of ore at one per cent BeO, was being developed in 1998. Gem varieties of beryl are aquamarine (clear blue), emerald (clear green), morganite (rose coloured), and it also occurs in yellow, pale violet, and other coloured varieties. Most of the small historic Australian beryl production was hand picked as a byproduct or co-product of mining pegmatite or greisen bodies. Beryl and other beryllium ores are sold on a basis of minimum ten per cent BeO, with the sale price quoted as $US per short ton unit.

BISMUTH Estimated world production of bismuth was about 4500 tonnes in 1998. Common ore minerals are native bismuth, bismuthinite (Bi2S3), bismutite [nominally (BiO)2CO3], and bismite (bismuth ochre, Bi2O3). These usually occur as traces in other metal ores, and are frequently a deleterious impurity; ie smelters impose a penalty for bismuth in metal concentrates or may not accept them. Bismuth is a major constituent of Tennant Creek copper-gold orebodies such as Gecko and Warrego, which contains 0.3 per cent Bi. The principal impurities in bismuth ores are arsenic, antimony, copper, lead and sulphur. Bismuth metal is sold in tonne lots, with the price quoted in $US per pound.

BORON Total world demand was about 1.25 million tonnes of B2O3 in 1997, and known world reserves are >100 million tonnes of contained B2O3 (Crowson, 1996, p 64). There is no present Australian production. Production of borates is dominated by the Turkish State organisation Etibank, and Rio Tinto Borax, from open pits at Boron in the Mojave Desert of California and Tincalayu in Argentina. The borax industry is described in detail in Marcus (1997). The principal mineral sources are kernite (rasorite or pentahydrate, Na2B4O7.4H2O, with 51 per cent B2O3), borax or tincal ore (decahydrate, Na2B4O7.10H2O, with 36.5 per cent B2O3), the calcium borates colemanite (Ca2B6O11.5H2O, with 50.9 per cent B2O3) and ulexite (NaCaB5O9.8H2O, with 43 per cent B2O3), and the magnesium borate, boracite (Mg3B7O13Cl, with 62 per cent B2O3). All of these are mined from non-marine salt lake or evaporite deposits that formed as playa lakes in arid areas. The principal known deposits are in western Turkey, the western US and the Andes; all are associated with ignimbrites. The ores are purified by solution and evaporation. Minor quantities of boron chemicals are provided by cleaning boric acid from geothermal steam, prior to its use in power generation, particularly in Italy. Sales are on a bulk tonnage basis, with minimum 99.5 per cent boron chemical content. Anhydrous pentahydrate and decahydrate command a premium, and must contain a maximum of one per cent water.

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BROMINE Total world production is about 400 000 tonnes per year, from natural sodium bromide in seawater and brines. Sales specifications are a minimum of 97 per cent bromine, with a premium for 99.5 per cent grade, no iodine, <0.1 per cent chlorine and a density of >3.1.

CADMIUM, GALLIUM, GERMANIUM AND INDIUM All of these metals occur as traces in sphalerite, and are available from refining zinc concentrates. About 80 per cent of the world’s cadmium is obtained by refining zinc ores, and the remainder from refining of lead and copper ores and recycling. To a lesser extent germanium and indium are available from smelting of polymetallic tin, lead and copper ores, and gallium is recovered during the processing of bauxite to alumina. Estimated 1998 world production was about 20 000 tonnes of cadmium, 60 tonnes of gallium, 56 tonnes of germanium and 240 tonnes of indium. They probably occur as simple sulphides in solid solution in sphalerite, which contains an average of about two per cent Cd (maximum about 3.5 per cent), 20 ppm Ga, 20 ppm Ge and 50 ppm In (maximum one per cent). No orebodies are mined solely for these metals. The principal cadmium-ore mineral is greenockite (CdS, 77.8 per cent Cd), usually as very fine grains or coatings. It is often stated that the honey yellow to brown varieties of sphalerite are cadmium rich, but even marmatite may contain up to one per cent cadmium. The form of the gallium in sphalerite is unknown, and the metal also occurs in coal, iron ores and bauxites (associated with vanadium). Germanium is known from argyrodite (4Ag2S.CeS2), germanite [Cu3(Ge,Ga,Fe)(S,As)4], with six to nine per cent Ge), euxenite, and from coal. The form of indium is uncertain, but it also found as traces in some bauxites and iron and manganese ores. All four metals report in the baghouse dusts from zinc concentrate refining, and these dusts may average about five per cent Cd, trace to one per cent Ga, trace to three per cent Ge, and 0.2 per cent In. Australian cadmium production of about 1000 tonnes per year is entirely as a byproduct of smelting Broken Hill, Mount Isa and Rosebery lead-zinc concentrates. Cadmium metal is sold as small sticks or bar ingots, usually in lots of one to five tons, with the price quoted as $US per pound.

CAESIUM Total 1997 world production of caesium was of the order of a few tonnes, almost entirely from pegmatite deposits of pollucite [(Cs,Na)2Al2SiO4O12.H2O, with 30 to max. 42.5 per cent Cs2O]. Reserves of pollucite are estimated at about 100 000 tonnes, with the largest known resource a tantalum bearing pegmatite at Tanco

94

Lake, Manitoba. Byproduct caesium may be available from traces of the metal in beryl, carnallite (average 20 ppm Cs), lepidolite, leucite, petalite, triphylite and other potassium minerals.

CALCIUM (GYPSUM and LIMESTONE) Gypsum Most gypsum is used in building construction, as plasterboard or in cement. The Australian plasterboard industry uses two thirds of the gypsum (CaSO4.2H2O) produced, with annual production about two million tonnes. The commercial deposits are usually dunes or in salt lakes. The dune deposits are mined in shallow open pits, with the ore and gypseous overburden beneficiated by a simple washing plant to remove some of the impurities. Minimum ore grade is 90 per cent gypsum, and a typical analysis is shown in Table 4. Dredging of lake-bed gypsum from Lake Macleod (WA) began in 1997, and is expected to yield 1.5 million tonnes of gypsum per year from 1998, from reserves of about 6000 million tonnes of ore. The dredged gypseous mud is purified by heap leaching, which entails trickling water through the heaps for several months, to remove soluble salts. TABLE 4 Typical analyses of Marion Lake (SA) materials1. Material or component, %

Rock gypsum

Gypseous overburden

Gypsum

94.20

91.99

Sodium chloride

0.50

0.85

Calcium carbonate

4.38

5.57

Silica

0.20

0.12

Iron and alumina

0.20

0.15

1.

From McLeod (1966), p 303.

Some calcium sulphate of high purity is available as a byproduct of phosphoric acid manufacture. Limestone Crude limestone production in Australia exceeds 20 million tonnes per year, from around 200 quarries. Cement manufacture is the largest market, using about 1.4 tonnes of limestone per tonne of cement. All the major users have captive sources, but special logistic conditions may make major high grade deposits near the coast of commercial interest. Calcite (CaCO3, max 56 per cent CaO) of high purity and minimal magnesium content is required for commercial limestone; the specifications of the major New South Wales deposits are provided in Table 5.

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MINING AND ECONOMIC GEOLOGY

TABLE 5 Analyses of NSW limestones1. Component, %

Locality 1

2

3

4

5

6

7

8

9

CaCO3

98.98

97.16

97.57

92.05

96.64

96.16

96.39

97.56

97.30

MgCO3

0.69

1.04

1.05

2.00

1.06

2.45

1.07

1.60

0.51

MnCO3

0.02

0.02

0.02

ND

0.04

ND

0.02

0.05

0.03

Insolubles

0.99

1.25

1.04

5.57

1.68

1.02

2.14

0.52

1.86

Fe2O3 + Al2O3

0.16

0.33

0.18

0.57

0.20

0.64

0.32

0.38

0.45

1.

From McLeod, (1965), p 356. Localities are: 1. Marulan, eastern belt, 2. Marulan, western belt, 3, 4. Carwell Creek, eastern belt, 5, 6. Brogans Creek, eastern belt, 7. Portland, 8. Ponsonby’s quarry, Rockley, 9. Attunga. ND = Not determined.

CHROMITE World chromite production was about 12 million tonnes in 1997. For chromite buyers the important open market ore variables are per cent Cr2O3, Cr:Fe ratio, SiO2 content, amount and ratio of Al2O3 and MgO, and sulphur and phosphorus content. About 70 per cent of world chromite production is used in metallurgical applications as alloys, about ten to 15 per cent is used in refractories, about eight per cent in foundry sands, and the remainder in the chemical industry. The only significant chromium ore mineral is chromite, a member of the spinel group, with formula nominally FeO.Cr2O3, ie 68 per cent Cr2O3. However, part of the ferrous iron is usually replaced by magnesium, and part of the chromium by aluminium or ferric iron, so that a more realistic formula is (Fe,Mg)O(Fe,Al,Cr)2O3 with 45 to 55 per cent Cr2O3. Chromite occurs almost exclusively in differentiated basic and ultrabasic intrusives. The only Australian production in 1997 was 31 000 tonnes of refractory grade chromite from the Coobina (WA) deposit. In recent years technological advances have enabled considerable interchangeability between traditional metallurgical, refractory, foundry, and chemical grades of chromite. Chemical grade chromite is now used in all four industrial applications. Consumers are now able to use chromite with a wider range of quality and grade specifications. The USBM classification is: High chromium chromite (metallurgical grade): with 46 per cent Cr2O3 or more, and a Cr:Fe ratio greater than 2:1; High iron chromite (chemical grade): Cr2O3 content between 40 per cent and 46 per cent, and a Cr:Fe ratio between 1.5:1 and 2:1, and High aluminium chromite (refractory grade): Al2O3 content more than 20 per cent, and Al2O3 and Cr2O3 content combined exceed 60 per cent. Lump chromite is generally preferred for ferrochromium production, though the proportion of fines used may exceed that of lump chromite in some

Field Geologists’ Manual

processes of low-carbon ferrochromium manufacture. SiO2 content is usually required to be less than ten per cent. In the manufacture of refractory bricks, chromite is required to be hard and coarsely crystalline, but for refractory mortars, fines are used. To maintain quality and refractory properties it is important for the SiO2 content to be below eight per cent, FeO below 15 per cent (some users tolerate a higher content), and CaO below two per cent (preferably around one per cent). For foundry sand applications chromite is required within specified size ranges and Cr2O3 content must exceed 44 per cent. Other specifications are (maxima) Fe2O3, 26 per cent; SiO2, four per cent; and CaO, 0.5 per cent. For chemical use, friable ore is preferred but lump or concentrates may be used. A Cr2O3 content greater than 44 per cent is often required by users. Desirable maximum levels of other materials are SiO2, eight per cent; FeO, 20 per cent; Al2O3, 14 per cent; MgO, 14 per cent; and CaO, three per cent.

CLAYS Clay deposits are bodies of loose, earthy, very fine-grained natural sediment or soft rock, composed largely of particles of less than 4 µm diameter of hydrous aluminium silicates. The clay minerals are largely formed by the decomposition of feldspathic rocks, and hence clay deposits contain fine grains of free quartz, decomposed feldspar, carbonates, ferruginous minerals and other impurities. The physical and chemical characteristics of each clay deposit are governed by the composition of the parent material and the manner of deposition. The most important commercial characteristics are plasticity, degree of swelling when wet, retention of shape after drying, shrinkage after drying, hardening by heating (firing), and firing shrinkage. Clay deposit dimensions are simply defined by drilling, and any body of uniform mineralogy close to a major population centre with reserves of more than

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one million tonnes may be of commercial interest. Clay mineralogy is usually defined by x-ray diffraction (XRD) analyses. The identification of the deposit ‘grade’ requires user tests on small composite samples, or on beneficiated samples, followed by more elaborate testing of bulk samples. Most of the State Mines Departments and the major users will carry out identification and usage cheeks. The broad clay types are discussed below, and further details are available from Carr (1994, pp 229-368). Brick clays, used in brick, tile and pipe manufacture, should be low in calcium, magnesium and organic matter, and contain sufficient iron oxides to impart an attractive colour to the finished product. Deposits of this grade generally contain less than 20 per cent Al2O3, and up to 50 per cent free silica; deeply weathered shale may be used for this purpose. Ceramic clays (kaolin, china clay) are largely kaolinite deposits, generally low in Fe2O3 and TiO2. Ceramic clays should fire white, and have a uniform kiln shrinkage. The largest market for kaolin is as a filler in paper and a component of paper coatings. The filler application requires a colour in excess of 80 ISO brightness, absence of abrasive grit (there are standard tests to define this characteristic), low viscosity, and particle size <10 µm. It should be noted here that the natural particle size of kaolin is essentially <10 µm anyway, and therefore this requirement is not difficult to achieve. Coating clays are very high grade filler clays. Maximum whiteness is sought, and top particle size is generally 2-3 µm. The kaolin should be free of hard minerals or non-clay minerals, and in water suspension it should have a high thixotropy and low viscosity. Specifications for filler and coating clays include low levels of iron oxides and titania, and cosmetic kaolin must have a maximum of two ppm arsenic, 20 ppm heavy metals and 350 ppm chlorides. The next most important area of consumption is ceramics generally, including fireclays, enamel, and glass. These clays should all generally be low in iron and other colouring materials, be low in alkalis, fire white, and have a consistently low viscosity. Kaolin is also widely used as a filler, notably in paint, cosmetic preparations, plastics and rubber. In all but the last application, prime requisites range from purity of colour to cheap price. In rubber, kaolin is divided into two categories: reinforcing clay and non-reinforcing clay. These in turn are related to particle size and shape. Paper grade kaolin commands a considerable premium, and a deposit close to a port with ample non-saline water and capable of producing 200 000 tonnes/year would be of great interest. To be successful the deposit should be capable of producing coating grade kaolin, ie high brightness, low viscosity and

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completely free of grit and water solubles. An important assessment to be made in the early part of any evaluation of a coating grade prospect would be to determine its ‘high shear’ or ‘Hercules’ viscosity. Modern, high speed coating equipment dictates very stringent properties of high shear viscosity. Chemical standards for the finished clay are broadly 38 per cent minimum Al2O3, loss on ignition about 14 per cent (assuming absence of carbonates), maximum 0.5 per cent Fe2O3, maximum 0.2 per cent TiO2, and a maximum of Na2O + K2O of 0.2 per cent. Known Australian kaolin deposits are at Weipa and Skardon River, Qld; at Elsmore, NSW; Pittong, Vic; Scottsdale, Tas, and at Greenbushes, Jubuk and Sparkes, WA. There has been intermittent production from Weipa and Greenbushes in the past, and the Elsmore and Skardon River deposits were being developed in 1997. The Weipa kaolin has a dry density about 1.5, overlain by an average of 6.5 metres of bauxite and mottled zone clays. The kaolin was mined by scrapers, then slurried and screened to remove grit; the slurry was then run through a high gradient magnetic separator and chemically leached to remove iron oxides and increase brightness. The slurry was then dewatered, and shipped in bulk; plant capacity was 100 000 tonnes/year. Average product specifications for this paper coating grade kaolin are shown in Table 6. Ball clay (pipe clay) is generally a sedimentary clay with high plasticity. It is very fine grained, commonly characterised by the presence of organic matter, and used as a bonding constituent of ceramic wares. It has high ‘workability’, high wet and dry strength, a long vitrification range, and may have high drying shrinkage. Most fire as white products. TABLE 6 Typical specifications for Weipa paper-coating grade kaolin. Parameter

Specification

ISO Brightness

86% minimum

Particle size distribution

92% < 2 µm, 45% < 0.2µm, 0.005% residue on 45 µm screen

Viscosity

Hercules bob at 1100 rpm at 71% solids = 2-3 × 105 dyne cm Brookfield No. 3 spindle at 100 rpm at 71% solids = 300-360 mPa.s

Moisture

0.5-2.0%

pH

6-7

Fireclay is a siliceous clay (fundamentally kaolin and free quartz), capable of withstanding high temperatures without deforming, and useful for the manufacture of refractory ceramic products such as crucibles, or

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MINING AND ECONOMIC GEOLOGY

firebrick for lining furnaces. It is deficient in fluxes (iron, calcium and alkalis), and approaches kaolin in composition, the better grades containing at least 35 per cent alumina when fired (Bates and Jackson, 1980). Bleaching clays (including attapulgite or fullers’ earth) are generally very fine grained and non-plastic, with a natural high absorptive capacity, and are used for bleaching, degreasing or absorption of liquids. The principal current use is in absorbent litter for pets, commonly known as ‘kitty litter’. Bleaching clays may be artificially activated. Bentonite is a soft greasy clay, containing largely montmorillonite clay minerals. The sodium-saturated bentonites have the capacity of absorbing large volumes of water with a major increase in volume, whereas the calcium bentonites are generally non-swelling. These are used in drilling muds and foundry applications. Specifications for drilling and foundry grades are provided in Griffith (1996, pp 20-21). Clays are mined in shallow pits, and the low value types are sold ex-mine without treatment. Australian production of brick clay and shale was about 16 million tonnes in 1990. The specialised clays (china clay and fullers’ earth, and particularly, paper grade kaolin and bentonite) may be washed, finely ground and screened to remove free silica and iron oxide impurities. All clay sales are priced in $ per dry tonne. Fullers’ earth is usually ground and bagged before sale, and bentonite is required to be at least 85 per cent minus 200 mesh.

COAL World production was about 3900 million tonnes of black coal and about 900 million tonnes of brown coal in 1998. Australian production of raw black coal was about 285 million tonnes in 1998, largely from Queensland (140 million tonnes) and New South Wales (136 million tonnes). About 82 million tonnes was obtained from open pits and 203 million tonnes from underground mines. Exports in 1998 comprised 83 million tonnes of coking coal and 84 million tonnes of steaming coal. Black steaming coal is produced for local use from the Leigh Creek (SA) and Collie (WA) fields. Victorian open pits produced 65 million tonnes of brown coal in 1998. The composition of black coal is determined by a complex array of analyses. At an early exploration stage, it is only necessary to define a few parameters by analysis of core samples, of which the first are total moisture and moisture after air drying (ad). Air dried samples are then analysed for ash, volatile matter, fixed carbon, total sulphur, total phosphorus, crucible swelling number (CSN), specific energy (in kcal/kg or

Field Geologists’ Manual

MJ/kg) and maximum fluidity (in dial divisions per minute or ddm). These preliminary analyses will define whether the coal is suitable for thermal, soft coking or hard coking use, but further analyses will be required prior to marketing. The indicative coal quality requirements for Asian consumers listed in Jones (1998, p 167) have been summarised in Table 7 to provide guidelines for acceptable export coal parameters. TABLE 7 Range of coal quality parameters acceptable to Asian users. Parameter

Unit*

Range of values

Specific energy (previously calorific value)

kcal/kg, ad

4225-6500

Total moisture, max.

%

8-28

Ash, max.

% ad

13-20

Volatile matter, max/min

% ad

31-60/15-27

Sulphur, max

% ad

0.9-1.6

Fuel ratio (fixed carbon: volatile material), max

2.2-2.5

Nitrogen, max

% daf

1.7-2.1

Chlorine, max

% daf

0.01-0.05

Hardgrove Grindability Index (HGI), min.

45-59

Ash fusion temperature, Min def Min hemi Min flow

°C

Size, max diameter

mm

Ash composition, Na2O max Na2O + K2O max

%

1190-1400 1300-1320 1350 40-64 0.1-3.0 3.0

Notes: ad = air dried, daf = dry, ash free.

Brief descriptions of New South Wales coal mines and coal quality are shown in Armstrong (1998); similar details for Queensland mines are in DME (1998). Detailed quality specifications for black coals from all Australian mines and a glossary of coal quality terms are provided in Jones (1998, pp 169-187 and 166) Calculation of insitu coal resources Multiply the volume of coal in cubic metres by the apparent density to obtain resources expressed as tonnes, or hectares × 104 × thickness (in metres) × apparent density = tonnes.

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COBALT World cobalt production was about 30 000 tonnes in 1998. The common ore minerals are cobaltite (CoAsS), linnaeite (Co3S4), smaltite, and asbolite (cobaltian wad, with up to 15 per cent Co), usually occurring as accessory minerals in copper, lead-zinc and nickel sulphide ores, or as oxides in manganese and nickel oxide ores. Treatment of sulphide and oxide cobalt ores is by very different processes. Present Australian production is a byproduct of refining of nickel, copper and zinc sulphide ores (mixed cobalt-nickel sulphide concentrates are saleable) and nickel laterite ores. Cobalt sulphides are separated from the other sulphides by flotation, generally producing a mixed ‘minor sulphide’ concentrate. This is roasted and smelted several times to produce cobalt oxide, which may be reduced by heating in an electric furnace or purified by electrolysis. Saleable concentrates must contain a minimum of ten per cent Co. Cobalt is obtained at the Yabulu treatment plant near Townsville from asbolite and other oxide ores by reduction roasting, ammonia leaching, and precipitation. Cobalt is obtained from the nickel-cobalt laterite ores from Bulong, Cawse and Murrin Murrin in WA. These average about 0.7 to one per cent Ni and 0.04-0.1 per

cent Co, and are treated, after fine grinding, by acid pressure-leaching at 250°C to dissolve nickel and cobalt. After partial neutralisation of free acid to precipitate iron, the pregnant solution and leach residue are separated by counter-current decantation (CCD). A mixed Ni-Co product is then obtained by alkali or sulphide precipitation, redissolved in ammonia or acid solution, and the nickel and cobalt are separated by solvent extraction. The separate high-grade cobalt and nickel products are then recovered from solution by electrowinning or hydrogen reduction. Annual production from the three areas is about 63 000 tonnes of nickel and 5500 tonnes of cobalt. Sales of cobalt metal are quoted in $US per pound.

COPPER Total world mine production of copper was about 12 million tonnes in 1998. The most important ore minerals, chalcopyrite (CuFeS2), chalcocite (Cu2S), and bornite (Cu5FeS4), accounted for more than 80 per cent of mine production, with the remainder being won from other copper sulphides and from oxidised ores. Production statistics for a range of mine sizes are listed in Table 8, to illustrate typical ore grades, production and recovery.

TABLE 8 Copper mine production statistics. Mine details

Ore milled

Product

Recovery/comments

Bougainville open cut, 1987

48.2 Mt at 0.41% Cu, 0.43 g/t Au and 1.33 g/t Ag

585 000 t of Cu conc. at 30.4 % Cu, 25.8 g/t Au and 86.4 g/t Ag

Rec. 90.2 % for Cu, 72.8 % for Au and 78.9 % for Ag. Mine closed in 1989

Mina Alumbrera open cut, Argentina, 1997-98

9.17 Mt at 0.79 % Cu and 0.93 g/t Au

Cu conc. containing 537 687 t of Cu and 148 323 oz of Au, plus 13 876 oz Au in dore

Rec. 74.2 % for Cu, 59 % for Au

Ernest Henry open cut, Qld, 1997-98

3.291 Mt at 1.04 % Cu and 0.61 g/t Au

Cu conc. containing 26 014 t Cu and 33 751 oz Au

Rec. 76 % for Cu, 52 % for Au

Olympic Dam, underground, SA, 1996-97

5.206 Mt at 3.03 % Cu, 0.54 g/t Au, 6.48 g/t Ag and 0.85 kg/t U

Smelter products were 131 023 t Cu, 49 333 oz Au and 608 514 oz Ag; also 3111 t U in conc.

Overall recoveries of 83 % for Cu, 55 % for Au, 56 % for Ag, 70 % for U

Mount Isa Cu, underground, Qld, 1997-98 Mt Lyell underground, Tas, 1996-97 Osborne underground, Qld, 1998 Cobar underground, NSW, 1995-96 Eloise underground, Qld, 1998

4.475 Mt at 3.5 % Cu

Anode Cu

Concentrator recovery 93.3 %, smelter recovery 97.1 %

1.8 Mt at 1.3 % Cu

81 405 t conc. containing 21 721 t Cu and 13 669 oz Au

Rec. 93 % for Cu

1.49 Mt at 2.6 % Cu and 0.9 g/t Au

Cu conc. containing 35 989 t Cu and 31 178 oz Au

Rec. 93.7 % for Cu, 72.5 % for Au

961 274 t at 3.39 % Cu

104 333 t Cu conc. Containing 31 804 t Cu

Rec. 97.6 %. Mine closed in 1997

230 054 t at 4.41 % Cu and 1.34 g/t Au

33 435 t Cu conc. at 28.71 % Cu and 5.67 g/t Au

Rec. 94.6 % for Cu, 65.4 % for Au

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Concentration and smelting Copper sulphide ores are concentrated by flotation, after crushing and grinding to at least <52 mesh. The flotation process may involve a range of additives to selectively depress or activate individual minerals, depending on the number of sulphide species present. Problems arise due to complex mineralogy, requiring a number of flotation stages, and with intergrown fine grained ore minerals, which may necessitate very fine grinding to liberate individual particles. Reactive sulphide minerals, particularly fine grained pyrrhotite, can cause problems in flotation. Some micas can cause problems in achieving concentrate grade. Variations in copper sulphide surface chemistry, particularly the formation of an oxidised skin on sulphide grains, cause losses in flotation. These variations may be anticipated by assaying representative samples for ‘oxide’ copper as well as total copper, and subjecting highly oxidised sulphide ores to pretreatment such as sulphidising. This converts the surface of copper oxides to copper sulphides amenable to flotation. In general terms, copper sulphide ores should not be exposed to weathering - either avoiding atmospheric weathering by mining at the milling rate, or providing cover for stockpiled ores. High grade oxide and sulphide ores may be shipped directly to a smelter, without prior concentration. Depending on the distance involved the minimum grade for direct shipping ore is about 15 per cent copper. Small quantities of much lower grade ore may be accepted by smelters under special conditions, particularly those ores with siliceous gangue (generally a minimum of 65 per cent SiO2). Lower grade oxidised ores may be concentrated by sulphidisation and flotation, or they may be heap leached with dilute sulphuric acid, followed by solvent extraction of copper from the pregnant solution, and electrowinning (SX-EW) of copper as cathodes. Small

operations recover copper ‘cement’ (fine grains of metallic copper) precipitated from the copper sulphate solution on steel (scrap, pellets, etc). Recovery can range from less than 70 to more than 90 per cent. Low grade ores may also be leached with ammonia; copper oxide is precipitated and recovered by boiling off the ammonia. Penalties are charged by smelters for deleterious metals in copper ores and concentrates. The penalty is calculated at a rate per tonne unit if the assay of the metal concerned exceeds the following limits: antimony 0.2 per cent, arsenic 0.2 per cent, bismuth 0.05 per cent, lead 1.5 per cent, selenium, 0.02 per cent and zinc five per cent. Some smelters also require a very low nickel content. For fine grained material such as residue, concentrate, precipitate, slime, etc, a draughtage deduction of one per cent of the net dry weight of material is applied. Smelting charges at a typical copper smelter (Table 9) are based on1: Treatment charge: $US 90 per dry tonne of material received. Refining charge: $US 0.09 per pound of payable copper, $US 5.00 per ounce of payable gold and $US 5 per ounce of payable silver Metal deductions: Copper - Pay for 96 per cent of the copper content subject to a minimum deduction of one unit Gold - Deduct one gram per dry tonne and pay for 90 per cent of the balance Silver - Deduct 30 grams per dry tonne and pay for 90 per cent of the balance 1.

Data supplied by Port Kembla Copper Pty Ltd.

TABLE 9 Estimate of the net smelter return from 100 t of copper conc at 28 per cent copper, 5 g/t gold and 150 g/t silver. Item

Weight

$ prices

$ value 43 008.00

Payable copper

26.88 t (ie 28 t × 0.96)

1600.00

Payable gold

0.36 kg (ie 4 kg × 0.9)

9002.20

3240.79

Payable silver

10.8 kg (ie 12 kg × 0.9)

160.75

1736.10

TOTAL Less charges: Treatment charge

47 984.89 100 t

90/t

9000

Copper refining charge

26.88 t

198.42

5333.53

Gold refining charge

0.36 kg

160.75

57.87

Silver refining charge

10.8 kg

16.08

173.66

TOTAL CHARGES

14 565.06

NET RETURN PAID

33 419.83

Note: the above terms assume impurities to be below penalisable levels.

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Copper is paid for at the LME settlement quotation for copper ‘A Grade’. Pricing of silver and gold are also based on London Bullion Market quotations. As an example, assuming 100 dry tonnes of concentrate at 28 per cent copper, 5 g/t gold and 150 g/t silver, and sale prices of $1600/t for copper, 280/oz for gold and 5/oz of silver, the net smelter return may be calculated as shown in Table 9.

DIAMONDS1 The primary sources of economic diamond deposits are kimberlite and lamproite pipes and dykes, and economic quantities are also found in secondary deposits in alluvial and marine gravels. Kimberlite and lamproite are complex volatile-rich potassic ultramafic rocks derived from the upper mantle. In addition to olivine and phlogopite, they carry a distinctive but varying suite of upper mantle derived minerals dominated by pyrope garnet, chromian-magnesian spinel, magnesian ilmenite (picroilmenite), chrome diopside and zircon. Diamonds may or may not be present. Some of the chemical characteristics of diamond indicator minerals are given in section 2.3.5. ‘Diamond Indicator Minerals’. Kimberlite and lamproite are also characterised by trace elements associated with ultramafic rocks (compatible elements such as Cr, Ni, Co) as well as those related to alkaline rocks (incompatible elements, such as Nb, Zr, Sr, Ba, REE). Most diamond bearing kimberlites and lamproites are located within or marginal to Archaean cratons. Kimberlite and lamproite ages range from Proterozoic to Cainozoic. Exploration for kimberlites and lamproites is mostly carried out by systematically taking stream and loam samples for the diamond indicator minerals referred to above, and/or by geophysical techniques, mostly aeromagnetic, electromagnetic (EM) and gravity surveys. Airborne gravity surveys are a recent potentially useful development. Air photo studies can assist in identifying favourable structural settings and direct evidence of the intrusion of kimberlite and lamproite. Other remote sensing multispectral methods, based on infra-red wavelengths to detect Mg-bearing clays, the weathering products of the source rocks, can also be used. Geochemical prospecting methods are mostly limited to deposit delineation and are generally not used during regional exploration. The material collected in samples, from which heavy minerals are later extracted, is usually in the 0.2 to 1.0 mm size range. Pyrope garnet and chromian spinel (‘chromite’) are the most common indicators in the case of lamproite, and kimberlite additionally may contain picroilmenite and chrome diopside. To a large extent these diamond indication minerals (DIMs) can be visually differentiated from their common counterparts 1.

100

Information supplied by Bruce Wyatt of De Beers Australia Exploration Limited and Geof Fethers of Flagstaff GeoConsultants, Melbourne.

by trained mineral examiners, but microprobe analysis is also extensively used. Where DIMs are recovered from samples remote from their source their surface textures can provide information about likely travel modes and distances. Surface texture analysis, at times aided by Scanning Electron Microprobe, is often undertaken on DIMs where information on their transport history is sought. In the extensively weathered terrains that typify much of Australia, chromite can be the only DIM surviving the surface weathering environment. Ilmenite and chromite are more chemically resistant to chemical weathering than pyrope garnet and chrome diopside. In the Australian weathering environment full DIM suites of a kimberlite or lamproite source can often only be identified after the recovery and analysis of samples of fresh rock. Olivine, because it is susceptible to weathering, is not commonly encountered during prospecting for diamonds, but is relatively abundant in colder climates such as in Canada. In alluvial processes, pyrope garnet is the most mechanically stable of the DIMs and can be transported as individual grains by water flow for tens of kilometres after erosion from its source. Ilmenite is moderately resistant to mechanical break down whilst chromite and chrome diopside are least mechanically resistant and are seldom transported more than 5 km (often less than 2 km) from their source. Aeromagnetic techniques rely on identifying isolated dipolar anomalies (at least in mid latitude regions like Australia), typically based on surveys with a line spacing of 300 m or less and a sensor height of 60 m flown N-S. Anomalies are often verified by ground surveys, or increasingly by detailed airborne surveys (helicopter or low altitude aircraft). EM techniques rely on the conductive characteristics related to the weathered and clay rich surfaces of kimberlites and lamproites. Radiometric data are of limited value for the direct detection of kimberlites. Gravity anomalies over the bodies are typically lows associated with the weathered, and therefore low density, upper portion of the pipes. Economic concentrations of diamond in kimberlites and lamproites vary from less than 20 carats (1 carat = 0.2 grams) to several hundred carats per hundred tonnes (i.e. 0.04 to more than 1 ppm). This large range in viable grade is largely due to the varying quality and size distribution of diamonds from the different localities, the average value per deposit ranging from about $US10 to over $US200 per carat depending on the ratio of gem to industrial stones. Economic deposits can range in size from about one hectare to over 100 hectares. The low concentrations of diamonds, even in rich deposits, associated with the variable quality, make it very difficult to evaluate potential discoveries, necessitating large samples (hundreds of tonnes) and sophisticated statistical analysis. Secondary diamond deposits are generally viable at lower grades than primary deposits as they usually contain better quality diamonds.

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TABLE 10 Figures in this table have been generated from company reports, published articles (Rombouts, 2001; Jennings and Smithson, 1999; Carlson et al, 1999) and communication with company representatives. The figures are a guide only, and all the value figures are unofficial and have not been verified by company representatives. For example, the Argyle lamproite has a grade of 549 ct/100t based on total past production whilst the current reserve grade is 300 ct/100t. The grade figures for the De Beers mines are mine recovered grades. Parameters of selected diamond mines Mine Jwaneng Udatchnaya Orapa Mir Ekati (Panda)

Company

Country

Debswana Alrosa Debswana Alrosa

2000 Production

Craton

Area (ha)

Grade ct/100t

Value $US/ct

Ore treated Mtpa

Value $USm

Botswana

Kaapvaal

55

125

115

9.2

1,325

Russia

Siberian Platform

20

100

80

9

1,000

Botswana

Kaapvaal

110

83

50

14.7

609

Russia

Siberian Platform

7.2

150

?

?

BHP Billiton

Canada

Slave

3

90

168

3.3

499

Venetia

De Beers

RSA

Kaapvaal

17

122

90

3.7

405

Argyle

Rio Tinto

Australia

North Australian

46

549

13

10

338

Finsch

De Beers

RSA

Kaapvaal

18

46

75

4

144

Premier

De Beers

RSA

Kaapvaal

32.2

63

80

2.9

143

Mbuji-Mayi

Sibeka

Congo

Kasai-Congo

18.6

600

15

1.5

135

Marsfontein

De Beers

RSA

Kaapvaal

0.4

82

115

0.5

50

Mwadui

De Beers

Tanzania

Tanzanian

146

6

145

3

46

Merlin

Rio Tinto

Australia

North Australian

<4

20

113

0.6

14

Diavik

Rio Tinto

Canada

Slave

6.1

400

63

proposed

Kimberley

De Beers

RSA

Kaapvaal

3.6

16.4

200

ceased

Lesotho

Kaapvaal

16

3.5

400

ceased

Letseng

Diamond pipes are mostly mined by open cast techniques in their initial stages, and later by normal underground techniques given favourable grades. Diamonds from secondary deposits are mined by standard alluvial methods. Recently, diamonds off the west coast of South Africa and Namibia have been extracted using ships equipped with specially modified dredging equipment. Diamond recovery is usually achieved by crushing, screening and dense media separation to produce a heavy mineral concentrate. Final extraction of the diamonds is by X-ray and/or grease belt. The estimated value of world wide rough diamond production in 2000 was $US7.9 billion (Rombouts, 2001) with Botswana, Russia, South Africa, Angola, Namibia and Australia being the major individual producers. Canada will be a very significant individual producer as a result of the new BHP Billiton owned Ekati mine which opened in 1998, and several other potential mines are likely to come on stream in the next few years. Historically, most gem diamond production was sold through the Central Selling Organisation associated with the De Beers group. However, recent

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times have seen a progression to much more diverse and independent marketing arrangements. Kimberlites are found in all the cratonic regions of Australia including the Proterozoic-covered North Australian Craton. Lamproites are located on the margins of the Kimberley block. The Argyle mine (Table 10) produced 26 million carats of diamonds in 2000, making it the largest world producer, with 24 per cent of world production by volume. As most of the production from Argyle is industrial diamonds (average $US13 per carat) this represents 4.3 per cent of world production by value, worth $US338 million (Rombouts, 2001). The deposit is a lamproite pipe, has an area of approximately 50 hectares, is 2 km long and varies in width from 150 to 500 metres. Merlin is a new small kimberlite diamond mine in the Northern Territory, discovered by Ashton Mining. The field comprises 12 pipes up to 1.1 ha, four of which currently constitute the mine, and came into production in 1999. Total diamond production from Merlin in 2000 was 0.2 million carats at an average price of $US113 per carat (Rombouts, 2001).

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A new mine, owned by Kimberley Diamond Company NL, is under development at Ellendale (North Australian Craton). It is based primarily on enriched diamond grades (30 ct/100t @ $US100/ct) identified in surface lag deposits overlying parts of two lamproite pipes which have a combined surface area of 122 ha and comprise both barren lamproitic material and diamond bearing pyroclastics grading 7 ct/100t. The reader is referred to the special issue of the Journal of Geochemical Exploration, (Griffin, 1995), for additional information on diamond exploration.

FLUORITE Fluorite (fluorspar, CaF2, with 48.9 per cent fluorine) is the only commercial source of fluorine in Australia. Although it is a gangue mineral in many sulphide deposits, this material cannot usually be cleaned to acceptable purity, and commercial fluorite is mainly won from limestone replacement deposits and vein bodies. In these deposits the ore grade is generally > 20 per cent fluorite. World fluorite production was about four million tonnes in 1998. Some minor vein deposits are upgraded by hand sorting, but most ores are selectively mined and beneficiated by gravity separation (tables or jigs) or by flotation. Product sizing specifications are 100 per cent minus 25 mm, with maximum 15 per cent of minus 1 mm for metallurgical grade, and 100 per cent minus 100 mesh for ceramic and chemical grades. Standard specifications are shown in Table 11. Waste fluorine obtained, as a byproduct from treatment of fluorapatite (one to five per cent fluorine) in fertiliser works, is the only known alternative source.

GEMSTONES The precious stones of commercial interest other than diamonds (q.v.) are ruby, sapphire, emerald, and opal.

With the exception of opal, common characteristics are brilliance (ie a high refractive index), hardness greater than seven, and a clear and attractive colour. Company-style mining requires very large deposits of reasonably uniform grade, so that bulk long-term mining and marketing can be planned. A wide range of attractive minerals, with lesser hardness, is available as lower cost semiprecious stones; Australian deposits of agate, amethyst, aquamarine, beryl, garnet, jade, rose quartz, tiger eye, topaz, tourmaline, turquoise and zircon are known. Emerald is the clear green variety of beryl (q.v.). It is selectively hand mined from primary pegmatite deposits, with alluvial workings a minor source. Primary emerald deposits are known from NSW, the NT and WA. The US is by far the world’s largest market. Sapphire (blue, green or yellow corundum) is mined in northern NSW at Inverell-Glen Innes and in central Qld around Anakie. Most sapphire mined to date occurs in Recent gravel one to two metres thick in present day stream channels, and in larger areas of Tertiary sediment. The primary source of the NSW sapphires is a Tertiary volcaniclastic rock (tuff) near the base of the basaltic pile, but is sub-economic. Sapphire dirt is removed by earthmoving equipment such as mechanised shovels and trucked to wet screening plants and jigs. Sapphire concentrate is screened, sorted and graded by hand. Spinel is removed by a magnetic separator. The silky appearance caused by impurities is removed by heat treatment, which may also enhance or lighten the blue colour. Most rough sapphire is exported to Thailand for heat treatment, preforming and facetting. Ruby, the red form of corundum, is comparatively rare in Australia, but a deposit near Gloucester, NSW, was being appraised in 1999.

TABLE 11 Specifications for fluorite. Component

Chemical - acid grade, %

Chemical - cryolite Ceramic grade, % grade, %

CaF2 min.

97.0

97.0

90 (prefer >95)

SiO2 max.

1.5

1.1

3

S max.

0.03

0.03

CaCO3 max.

1.25

-

Fe2O3 max.

0.25

Pb max.

0.20

Zn max.

0.20

*

102

Metallurgical A grade, %

Metallurgical B grade, %

70*

60*

0.3

0.3

0.5

0.5

1.0

Specifications quoted are the ‘effective’ CaF2 content, calculated by deducting two per cent from the CaF2 assay for each 1 per cent SiO2. Note that barite is objectionable in metallurgical grade, and must be practically absent from other grades.

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Opal is mined in SA at Mintabie (now the largest producer), Coober Pedy and Andamooka; in NSW at Lightning Ridge and on a small scale at White Cliffs; and in western Qld, where the mining of boulder opal has expanded considerably in recent years. Opal is found in seams on either horizontal ‘levels’ or steep ‘verticals’, as veins and nodules - called ‘nobbies’ at Lightning Ridge and ‘nuts’ in Queensland. Opal probably formed during the second major silicification event in Oligocene times, in weathered Cretaceous marine siltstone and claystone at all main locations except Mintabie, South Australia. Here the host rock is weathered Devonian or Ordovician sandstone. Mining to 30 m below surface is by either open cut or underground methods. Open cutting varies from small scale backhoeing to high volume quarrying at Mintabie with D9/D10 size bulldozers and scrapers. Underground, individual miners use pneumatic jack picks, air/electric/petrol winches and automatic bucket tippers, with syndicates driving the ‘level’ with tunnelling machines linked to either blowers (truck or trailer-mounted giant vacuum cleaners) or bucket elevators to haul waste to the surface. Access is provided by 1 m diameter shafts drilled by Calweld bucket rigs. Since 1986, small rubber tyred air or diesel front-end loaders and boggers have become popular, operating from the face of an old open cut. In SA, opal is generally mined selectively at the face, and cleaned and graded on site. At Lightning Ridge, opal dirt is often carted from the mine site for treatment by dry and/or wet puddlers (mechanical screening plants). Noodling machines recover opal from old dumps by trommel screening, followed by hand picking in a darkened air-conditioned room lit by ultra violet light. Most rough opal is exported to Hong Kong, Taiwan and China for cutting, although there has been an increase in further processing in Australia since 1987. Jade is mined at Cowell on Eyre Peninsula, where 115 known lenses and pods of nephrite jade were formed in dolomitic marble of Middle Proterozoic age during the last stages of the Delamerian Orogeny. Mining is limited to short campaigns of a few weeks duration, which usually provide several years’ supply. Waste rock is drilled, blasted and removed by front end loader to expose a wall of jade. Boulders and slabs of jade are prised from the face by a hydraulic rock-breaker mounted on a crawler tractor, and trucked 30 km to Cowell for sorting and stabbing by diamond tipped saws. Chrysoprase, a green jade-like mineral, is mined in Qld and SA.

GOLD World production of mined gold for 1998 was 2555 tonnes (about 823 million ounces). Australia was the third largest producer, at 313 tonnes, after South Africa with 474 tonnes and the US with 364 tonnes.

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Western Australia was the largest Australian producer, with 228 tonnes (73 per cent), followed by Queensland with 32 tonnes. The principal ore mineral is native gold, although gold tellurides, with or without silver, are important sources in the Eastern Goldfields of Western Australia. Gold invariably occurs alloyed with silver, and its colour ranges from the bright golden yellow, low silver ‘gold’ of fineness about 900 to a silvery white colour with fineness below 500. Fineness is a measure of gold purity in parts per thousand, thus ‘gold’ of 900 fine is 90.0 per cent pure gold. The term bullion, quoting the relevant fineness, is preferred for newly mined unrefined gold, to avoid confusion between pure gold of 1000 fine (called fine gold) and the mine product with its inherent silver content. Gold bars smelted at the mine site commonly contain > 95 per cent gold, and are called ‘doré’. Native gold may also contain small quantities, up to several per cent, of copper, bismuth, zinc, platinoids, and traces of other metals. There has been a startling growth in the Australian gold mining industry, from 18 tonnes produced in 1980 to more than 312 tonnes in 1998. This growth was initially due to the increase in the price of gold, from about 1980, and the very large store of known gold deposits available for evaluation. The most important factor was the development of large scale and low cost open pit mines at these deposits. In addition, the development of cheaper cyanidation processes, particularly the carbon in pulp (CIP) and carbon in leach (CIL) techniques and heap leaching, allowed treatment of lower-grade orebodies. Critical geological factors in the development of this new generation of gold mines included rapid exploration by pattern rotary air blast (RAB) and reverse circulation (RC) drilling, with an enormous number of holes drilled in WA. Other factors were a better understanding by geologists of the metallurgical features of ore deposits, and a systematic mine ore grade control system, often by sampling of trenches or bulldozer ripper cuts in the oxidised ores. Mining of alluvial deposits is currently insignificant in Australia, although these have been major historic sources. The only recent example was the large scale dredging of the Grey River (NZ) deposits, that have an average head grade around 130 mg/m3 gold. The price of gold was fixed for long periods in the past, so that gold grades for some deposits (particularly in the USA) were quoted in $US per ton or per short ton. These values can be converted to ounces per short ton and thus to ppm gold from the official gold price which was $US 20.67/oz to September 1933, then $US 35 to 1971, $38 in 1972 and $US 42.22 from 1973 to 1978. The price varied with demand after 1978.

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The range of gold assays in exploration and mine samples is often very large, from a few ppb to thousands of ppm, in a small batch of samples. Thus it is not usually possible to calculate a meaningful average grade without extensive sampling and check assaying. In operating mines, unusually high assays are often cut to a limit (a ‘top cut’ or ‘upper cut’), that is established, from a long term correlation of mine assays with mill returns. Underground mining of gold deposits requires careful and extensive sampling of development openings and working faces, to avoid dilution with barren or low grade material. An overall frequency of one sample for each few tonnes of ore milled is not unusual. Ore treatment involves crushing and fine grinding, with a gravity concentration section to recover coarse gold from free milling ores, ie those in which the gold grains are coarser than about 100 µm, and are liberated by fine grinding. Amalgamation of free gold with mercury is rarely used in Australia now, due to the unfavourable environmental impact of mercury. The gravity concentration stage is followed by a cyanidation section in which the gold is dissolved in a weak solution of sodium cyanide. Gold is recovered from the pulp by contact with activated carbon in the CIP processes, and from the filtered leach solution in the CIL procedure. The carbon is screened from the pulp and the gold is recovered. Refractory ores, in which the gold is intimately mixed with sulphides, may be treated by flotation to produce a sulphide

concentrate that is either cyanided directly or roasted before cyanidation. Biological oxidation (BIOX) of refractory ores is used at some mines. Heap leaching of low grade ores is an established treatment process in Australia. The process involves dumping ore on an impermeable pad, usually after coarse crushing, applying the cyanide liquor to the heap, and treatment of the pregnant liquor in a conventional CIL plant. Recoveries were in the range 56-85 per cent at the operations described by Woodcock and Hamilton (1993, pp 1061-1073). Sodium cyanide consumption is an important cost actor in ore treatment. However, some ores contain minerals that react with cyanide (cyanicides), which may render cyanidation prohibitively expensive. The major cyanicides are oxidised copper and zinc minerals, and other deleterious minerals include partly oxidised sulphides such as stibnite and arsenopyrite, and nickel sulphides. Cyanidation generally requires at least two tonnes of water per tonne of ore treated, but saline water may be acceptable. Most Australasian production is from mining of ores in which gold is the only important commodity. Refer to Table 12 for production data from some Australasian gold mines in the 1997 calendar year or the 1997-98 financial year, from the ‘World Gold Analyst’ of November 1998. The Gold Institute Standard, adopted by most Australasian mining companies, defines three levels of gold production costs. Cash operating costs comprise direct mining, stripping and mine development costs,

TABLE 12 Production data for some Australasian gold mines. Mine and ore type (o.c. = open cut, u.g. = underground)

Ore treated (Mt)

Kelian o.c., Kalimantan, Indonesia, 1997

7.352

Porgera u.g., PNG, refractory, 1997 Kidston o.c., Qld, 1997-98

Head grade Gold recovered (g/t Au) (oz)

Recovery (%)

2.79

484 000

73

4.382

6.9

712 696

73

6.150

1.17

191 250

82

Mt Leyshon o.c., Qld, 1997-98

5.501

1.6

249 085

89

Nolans o.c., Ravenswood, Qld, 1997-98

1.163

1.49

52 974

95

Tanami u.g. & o.c., NT, 1997-98

1.439

4.8

212 447

96

KCGM 'superpit' and Mt Charlotte u.g., WA, 1997

13.2

2.5

851 828

89

Jundee-Nimary, u.g. & o.c., WA, 1997-98

2.872

3.3

293 016

95

3.4

3.2

274 608

88

Kaltails tailings, WA, 1997-98

7.448

0.6

72 790

51

Boddington o.c., WA, 1997-98

8.632

1.0

258 681

91

Plutonic u.g., WA, 1997

Granny Smith o.c., WA, 1997

4.2

4.0

493 000

92

Henty u.g., Tas, 1997-98

0.102

23.9

77 037

98

McRaes o.c., NZ, 1997

3.267

1.63

117 399

69

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plus refining and transport expenses. Total cash costs are cash operating costs plus royalties and production taxes. Total production costs are total cash costs plus non-cash items such as depreciation, depletion and amortisation, plus reclamation and mine closure expenses. Some Australian production is as a byproduct of mining polymetallic sulphide ores, notably the copper deposits at Tennant Creek. Gold was an important co-product from the Bougainville mine. Gold ingots, ex mine, are refined by smelting in the presence of chlorine, by aqua regia solution and sulphur dioxide precipitation, or by electrolysis. Refinery practice is described in Woodcock and Hamilton (1993, pp 1095-1101). There are no restrictions on buying or selling gold in Australia – as dore (mine smelted bars), nuggets, dust or in concentrates. Major purchasers of mine products, scrap and wastes are Australian Gold Refineries (Perth and Kalgoorlie), Johnson Matthey (Aust) Pty Ltd (Melbourne) and Golden West Refining Corporation Ltd (Perth); and for auriferous concentrates or slags Southern Copper Ltd (Port Kembla).

GRAPHITE World production of natural graphite was about 1.3 million tonnes in 1997, with China the largest producer. Synthetic graphite made from petroleum coke or pitch is a competitor. Natural graphite is marketed in classes based on particle size and carbon content. Crystalline lump graphite containing > 90 per cent C is the premium product, and flake graphite with > 80 per cent C is more valuable than amorphous graphite, that should have >70 per cent C. Prices are quoted in $US per tonne for the various grades.

HAFNIUM Hafnium occurs in most of the zirconium minerals such as zircon and baddeleyite, and in alteration products such as cyrtolite and malacon, to a maximum of about 30 per cent Ha. It is mainly used as hafnium metal in nuclear reactor control rods, and world consumption is less than 100 tonnes per year.

INDUSTRIAL MINERALS Industrial minerals are of commercial importance due to some particular physical or chemical property, unlike the metallurgical ores that are sources of refined metal. Specific mineral properties may be colour (for ochres and paper fillers), resistance to change when heated (refractories), insulating properties, hardness (abrasives), high density (barite) and raw materials for the chemical industry such as common salt and soda ash. In addition to articles on specific types of industrial minerals in Industrial Minerals magazine, useful general references are Carr (1994) and Harben and

Field Geologists’ Manual

Bates (1990). Perhaps the most important industrial mineral is water of acceptable quality, which is essential for every primary industry, often in large volume. Construction industry materials – various sands, natural aggregate and crushed rock – are not described herein; a useful basic reference is the section on construction materials in Woodcock and Hamilton (1993, pp 1343-1357). Most industrial minerals are of large bulk and low value as raw material, and can not sustain the cost of transport to remote markets. Thus many are produced for a local market, and frequently the local user is accustomed to the characteristics of the traditional material and loath to change to another supplier. For industrial minerals traded internationally, some of the established miners have operated for so many years that they dominate the trade, and set the price and standard for their product. Examples are Wyoming bentonite, Canadian chrysotile asbestos and Georgia kaolin. Nevertheless, a particularly large and high grade deposit of any material reasonably close to transport, may be of commercial interest. For such a deposit, infrastructure, shipping facilities and marketing may be the critical commercial factors. The industrial minerals described in individual sections herein are calcined bauxite (under aluminium), asbestos, barite (barium), borates (boron), gypsum and limestone (calcium), chromite (chromium), clays, fluorite (fluorine), lithium minerals, manganese ores, mica (including vermiculite), phosphates, potassium salts, rare earths, sodium salts, sulphur, and talc family minerals. Others are discussed below. Prices are generally quoted per tonne of beneficiated mine product of a particular composition, often screened to a specific size range. Prices are quoted in Industrial Minerals (Metal Bulletin Journals Ltd: London), monthly, and Minerals Price Watch, and the level of world production for some industrial minerals is available in Mining Annual Review (The Mining Journal Ltd: London). Abrasives include minerals with Mohs scale hardness from ten (industrial diamonds, q.v.) to one (talc). There is substantial trade in emery (natural corundum with iron oxides), calcined bauxite (q.v.), garnet, fused alumina, and silicon carbide. Most are marketed on a nearly pure (> 97 per cent) mineral basis at a particular particle size. Glazing materials are largely feldspars, either individual feldspar species or mixtures of several feldspars and quartz such as aplite, nepheline syenite and Cornish stone. These are largely used to make opalescent glass, glazes for ceramic products, and enamels for coating metals; a little is used as a filler. In all glass and glazing applications the Fe2O3 content should be < 0.35 per cent and preferably < 0.1 per cent. High calcium, potassium and sodium types are sought for different uses, and most are sold as a screened product. World production was about seven million tonnes of feldspar in 1997.

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Diatomite is largely used as a filtering medium, with minor applications as an insulant and a filler. The mixture of diatom species present in a deposit fixes the end use, as long needle-like forms are required for some purposes, and flat discoid shapes for others. Filter grade diatomite is calcined prior to sale. Insulants include asbestos (q.v.), vermiculite (q.v.) and perlite. The commercial term ‘perlite’ is applied to any fine grained to glassy igneous rock that expands to a much larger bulk on heating; most perlite is used in lightweight insulating plaster and concrete. It may be sold ex mine after crushing, or after expansion; inherent water content generally determines the end usage. World production of crude perlite was estimated to be 2.4 million tonnes in 1997, with about 65 per cent from mines in the US, Greece and China. Demand for perlite is related to the level of activity in the building and construction industries. Refractories include bauxite (q.v.), graphite (q.v.), dead-burned magnesite (q.v.), concentrates with more than 90 per cent olivine, sillimanite-family minerals and wollastonite, plus clays (q.v.) used as a binder for these minerals. Carr (1994, pp 841-850) provides a list of refractories and specifications for these. Annual world production of olivine concentrates is about 7.5 million tonnes, produced in a range of particle sizes from lump (ten to 45 mm diameter) to flour (<325 mesh). Critical composition requirements are 45-51 per cent MgO, 40-43 per cent SiO2, 0.2-0.8 per cent CaO, and low levels of Al2O3, TiO2, MnO, NiO and Cr2O3. World production of sillimanite-family minerals in 1997 was about 300 000 tonnes of andalusite, 110 000 tonnes of kyanite and a few thousand tonnes of sillimanite. Wollastonite production was about 400 000 tonnes in 1997. Ochres or pigments are used in their natural state or after calcining, to provide colour, body and opacity to paints and other products. World production of pigment in 1997 was about 400 000 tonnes. The principal constituent is iron oxide, produced by fine grinding many iron minerals or synthetically, and the group is divided into black, brown, red and yellow pigments (Carr, 1994, pp 765-781).

IODINE World production and consumption are in the range 15 000-20 000 tonnes per year, largely from brines associated with oil and gas and from Chilean nitrates. The world reserve base is large, at around ten million tonnes, and commercial iodine with > 99.5 per cent I is sold in $US per kilogram.

IRON World iron-ore production for 1998 was about 1000 million tonnes, including about 155 million tonnes from Australia, with much of the Australian production exported. About 98 per cent of Australia’s iron ore is mined in the Pilbara district of WA.

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The principal ore minerals for export are magnetite (Fe3O4), hematite (Fe2O3), goethite (FeO.OH) and limonite (nominally Fe2O3.nH2O, with 55 to 63 per cent Fe). Magnetite, siderite, iron sulphides (pyrite cinders), titaniferous magnetite and hematitic ilmenite are used in some countries, and comprise a small proportion of the export trade. Indicative export specifications for Australian iron ores are: Hematite and hematite-goethite ores: Lump ore: Sizing minus 30 mm plus 6 mm, min. 62 per cent Fe, max. 0.05 per cent S, max. 0.06 per cent P. Fines: Sizing minus 6 mm, min. 61 per cent Fe, max. 0.05 per cent S, max. 0.07 per cent P. Goethite ores: Sinter fines: Sizing 100 per cent minus 9.5 mm, 90 per cent minus 6 mm, ten per cent minus 0.149 mm; min. 56.5 per cent Fe, max. 0.05 per cent S, max. 0.05 per cent P. Brockman and some Marra Mamba hematite and hematite-goethite ores are largely produced for export, from the Hamersley Iron (Mount Tom Price, Brockman No. 2, Channar and Paraburdoo) and BHP (Jimblebar, Mt Newman and Yarrie) mines. There are several smaller operations. Mining and ore treatment at these areas are broadly similar. The ore is won with very large units of earthmoving equipment in large open pits, being selectively mined to avoid stratigraphic shale bands. The crude ore is crushed and screened at the mine or at the port, and the lump and high-grade fines are separately stockpiled and sold. Contact ore (material mined from the contact between shale bands and high grade ore) and scree ore (material mined from the talus pile at the edges of elevated orebodies) are first crushed and screened. The coarser fractions are upgraded by various gravity concentration methods, and the finer fraction by wet high-intensity magnetic separation (WHIMS). A slime fraction is discarded. Channel iron goethite-limonite ores are mined from various mesaform, Tertiary valley-fill deposits along the Robe River near Pannawonica and Deepdale, and at Yandicoogina west of Newman. The ore is crushed and the fines are used to produce sinter. The Savage River magnetite ores are mined in an open pit, finely ground and beneficiated by magnetic separation, and pelletised. Product grade is around 66 per cent Fe, 0.5 per cent TiO2 and 0.5 per cent V. Various proposals are in train in WA that involve mining magnetite-bearing banded iron formations, fine grinding the ore and concentrating the magnetite to give a high grade product. Titaniferous magnetite sand is mined from two deposits on the west coast of the North Island of New Zealand, at a rate of about 2.5 million tonnes per year. Production from the Waikato North Head deposit is used in the Glenbrook steel mill, and the sand from Taharoa is exported to Japan.

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MINING AND ECONOMIC GEOLOGY

Developments in WA and SA include the reduction of high-grade hematite or magnetite concentrates to metallic iron (direct reduced iron or DRI), using reformed natural gas. In some cases the DRI is briquetted (hot briquetted iron or HBI). Direct intensive bath smelting of DRI or HBI with bituminous coal will yield pig iron or semi-steel, that can be smelted to steel in an electric arc furnace. Iron ore exports are based on long term contracts, with prices quoted in $US cents per dry long tonne unit, ie per one per cent of contained Fe. Iron smelting consumes large quantities of water, coking coal (as coke), limestone and refractory grade clays.

LEAD, ZINC AND SILVER Estimated world production of newly mined metal in 1998 was about 3.1 million tonnes of lead, 7.8 million tonnes of zinc and 16 970 tonnes (546 million troy ounces) of silver. The three metals usually occur together, and the principal ore minerals are galena (PbS) and the zinc mineral sphalerite (ZnS) or its iron-rich variety marmatite. Low-iron sphalerite is preferred, due to environmental problems with disposal of iron residues at smelters that produce electrolytic zinc. Oxidised lead minerals, mainly anglesite (PbCO4) and cerussite (PbCO3), are occasionally recovered from high grade ores by gravity separation or flotation; ore grade (depending on the location of the deposit) is probably a minimum of ten per cent lead. Secondary zinc materials such as smithsonite (ZnCO3), hemimorphite (hydrous zinc silicate), willemite and coronadite occur in high grade bodies at Beltana (SA). Most Australian silver production is from argentiferous galena, in which some of the silver occurs as very fine grains of argentite (Ag2S) and tennantite, and some in solid solution in galena. The remainder is won as a byproduct of gold mining. Lead-silver-zinc sulphide ores are treated by coarse or fine grinding and differential flotation, to produce a lead-silver and a zinc concentrate. Copper-lead-zinc ores are treated by flotation, to give separate copper, lead-silver and zinc concentrates, and flotation of copper-zinc ores yields copper and zinc concentrates. Coarse-grained ores, as from Broken Hill, can yield high recoveries to high grade concentrates. Fine grained ores (Mount Isa, Rosebery and elsewhere), especially those containing pyrite, pose problems in achieving high recoveries in high grade concentrates. Typical analyses of Broken Hill concentrates are shown in Table 13. Results from some Australian lead-zinc mines are presented in Table 14. Lead concentrates are smelted at Mount Isa and Port Pirie, mixed lead-zinc concentrates are smelted in an ISF furnace at Cockle Creek, and zinc concentrates are treated at Risdon.

Field Geologists’ Manual

TABLE 13 Typical specifications for Broken Hill lead and zinc concentrates. Component

Lead conc.

Zinc conc.

Pb%

70.0

1.0 51.7

Zn%

4.8

Ag g/t

600

28

Au g/t

0.9

0.04

S%

16.1

31.2

Cu%

1.7

0.15

Cd%

0.02

0.16

As%

0.21

0.075

Sb%

0.16

0.012

Fe%

4.0

10.5

Bi%

0.02

Trace

Al2O3%

0.1

0.1

CaO%

0.2

0.17

Insolubles %

2.2

2.0

LITHIUM Western world consumption of lithium minerals in 1997 was about 145 000 tonnes (equivalent to about 16 000 tonnes of contained lithium), from production capacity of about 250 000 tonnes (Industrial Minerals, August 1998, pp 57-61). Production data for China and Russia are not available. The major mineral sources are spodumene (LiAlSi2O6, with nominally 8.4 per cent Li2O) in pegmatite deposits, lepidolite (lithium mica, with nominally about five per cent Li2O) and petalite (LiAl(Si2O5)2, with about five per cent Li2O). Other acceptable lithium mineral sources are amblygonite-montebrasite (lithium aluminium phosphate, with about ten per cent Li2O). Lithium salts from well and salt lake brines in Chile and Argentina yield lithium carbonate. Lithium compounds are used to make special glasses and ceramics. For lithium minerals used to produce ceramics and glass, the alkali, iron, lithium and silicon content are significant. Lithium and iron contents for commercial concentrates are shown in Table 15. TABLE 15 Typical specifications for lithium materials. Compon- High grade Glass grade ent spodumene spodumene conc.

Petalite conc.

Lepidolite conc.

Li2O, %

Min. 7.5

Min. 5

Min. 4.4

Min. 4

Fe2O3, %

Max. 0.1

Max. 0.2

Max. 0.05

Max. 1

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MINING AND ECONOMIC GEOLOGY

TABLE 14 Production data for some Australian lead-zinc mines. Mine details

Ore milled

Product

Recovery/comments

Mount Isa and Hilton, u.g., Qld, 1997-98

2.892 Mt at 7.2 % Zn, 6.6 % Pb and 176 g/t Ag

Zn conc. cont'g 147 033 t of Zn, and 146 040 t of crude Pb cont’g 11.128 Moz Ag

Conc. recovery of 73.4 % for Zn, 82.4 % for Pb and 74.9 % for Ag. Smelter rec. of 99 % for Pb.

Broken Hill, u.g., NSW, 1996-97

2.7 Mt at 8.2 % Zn, 5.2 % Pb and 53 g/t Ag

393 791 t of Zn conc. containing 196 371 t Conc. recovery of 88.7 % for Zn, 92.7 % for Pb and 83.1 % for of Zn; 191 269 t of Pb conc. containing Ag. See below for typical conc. 130 185 t of Pb and 118 922 kg Ag specifications

Hellyer, u.g., Tas, 1996-97

1.392 Mt at 11.9 % Zn, 6.0 % Pb and 155 g/t Ag

248 407 t of Zn conc. at 50.6 % Zn; 75 709 t of Pb conc. at 57.9 % Pb and 454 g/t Ag; 37 974 t of bulk conc. at 33.9 % Zn, 13.2 % Pb and 281 g/t Ag; and 12 510 t of Cu conc. at 11.0 % Cu and 4815 g/t Ag

Overall rec. of 83.6 % for Zn, 57.3 % for Pb and 48.8 % for Ag

Elura u.g., NSW, 1996-97

1.044 Mt at 8.5 % Zn, 5.7 % Pb and 94 g/t Ag

124 217 t of Zn conc. cont’g 62 498 t of Zn; 83 020 t of Pb conc. cont’g 43 166 t of Pb and 36 046 kg of Ag

Rec. 70.4 % for Zn, 72.5 % for Pb and 36.7 % for Ag

Golden Grove u.g., WA, 1996-97

907 901 t at 7.5 % Zn and 1.9 % Cu

109 777 t of Zn conc. cont’g 55 085 t of Zn; 59 607 t of Cu conc. cont’g 12 794 t of Cu

Rec. 80.9 % for Zn, 74.2 % for Cu

Cadjebut group, u.g., WA, 1996-97

837 856 t at 8.23 % Zn and 2.70 % Pb

107 209 t of Zn conc. at 61.9 % Zn; 25 615 t of Pb conc. at 76.83 % Pb

Rec. 96.2 % for Zn, 87.0 % for Pb

McArthur River, u.g., NT, 1997-98

798 000 t at 16.1 % Zn, 5.9 % Pb and 64 g/t Ag

Zn conc. cont’g 95 281 t of Zn; Pb conc. cont’g 26 280 t Pb and 915 474 oz Ag

Conc. recoveries of 74.3 % for Zn, 55.1 % for Pb and 55.3 % for Ag

Rosebery u.g., Tas, 1996-97

640 593 t at 10.0 % Zn, 2.9 % Pb, 0.4 % Cu, 104 g/t Ag and 1.5 g/t Au

108 390 t of Zn conc. cont’g 57 089 t of Zn; 19 877 t of Pb conc. cont’g 12 608 t of Pb, 28 305 kg Ag and 78 kg Au; 5855 kg of Cu conc. cont’g 1394 t of Cu, 18 765 kg Ag and 400 kg Au; and Dore cont'g 147 kg Au and 68 kg Ag

Overall recoveries of 89.1 % for Zn, 67.9 % for Pb, 70.8 % for Ag and 56.9 % for Au

Thalanga, u.g., Qld, 1996-97

601 000 t at 7.99 % Zn, 2.63 % Pb and 0.99 % Cu

75 551 t of Zn conc. at 57 % Zn; 14 874 t of Pb conc. at 63 % Pb and 14 894 t of Cu conc. at 28 % Cu;

Recovery of 89.7 % for Zn, 59.3 % for Pb and 70.1 % for Cu. Mining completed in 1998

Woodcutters u.g., NT, 1996-97

541 049 t at 13.7 % Zn, 5.3 % Pb

Zn conc. cont’g 63 390 t of Zn; Pb conc cont’g 17 037 t of Pb

Recovery of 85.3 % for Zn and 59.6 % for Pb

The principal mine producers in 1997 were Gwalia Consolidated Limited (spodumene, Western Australia), Tantalum Mining Corporation (spodumene and montebrasite, Manitoba), Bikita Minerals (petalite and spodumene, Zimbabwe) and Sociedad Minera de Pegmatites (lepidolite, Portugal). Gwalia Consolidated produced 114 900 tonnes of lithium minerals in the 1996-97 year, and resources were 13.65 million tonnes at 3.8 per cent lithium borosilicate.

MAGNESIUM Total world production of magnesium metal was estimated to be about 390 000 tonnes in 1998. The major raw materials are dolomite [(CaMg) (CO3)2, with nominally 21.7 per cent MgO], magnesite (MgCO3, with 47.6 per cent MgO), and magnesium salts, largely

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the chloride, from seawater, well brines and salt lakes. The metal is produced by electrolysis of magnesium chloride, and by electric smelting of dolomite. Carnallite (KMgCl3.6H2O, with 8.75 per cent Mg) is a possible alternative source; world resources of feed materials for the magnesium metal industry are enormous, but some large deposits contain undesirable impurities. Dolomite Large quantities of dolomite are locally mined and used as agricultural dolomite, for which general specifications are a Neutralising Value above 70, (CaO + MgO) minimum 35 per cent, and minimum 15 per cent MgO.

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MINING AND ECONOMIC GEOLOGY

Magnesite

Sintered/Electrofused Magnesia

World production of magnesite (MgCO3, with 47.6 per cent MgO) was about 19 million tonnes in 1997, and practically all of this was converted to magnesia. Total world consumption of magnesia was about eight million tonnes in 1997, of which about 6.7 million tonnes was derived from natural magnesite and the remainder from sea water and brine sources. Of this eight million tonnes, about 6.3 million tonnes was used as refractories and in high temperature insulants, as sintered (dead burned) or electrofused magnesia. The remaining 1.7 million tonnes was used as caustic-calcined magnesia in a wide range of chemical applications. Australia has large ‘rock’ magnesite resources, at Batchelor (NT), Kunwarara (Qld), northwest of Leigh Creek (SA), near Woodsreef (NSW), and at Main Creek, Bowry Creek and Arthur River (Tas).

This material is formed when caustic calcined magnesia is fused in an electric arc at a temperature of 2800°C. It is used in the manufacture of premium quality refractories and in high temperature electrical insulation. The current specifications are similar to those for dead burned magnesia.

Caustic-calcined Magnesia When magnesite is calcined to approximately 750°C (to drive off most CO2), a chemically reactive material known as light burned or caustic calcined magnesia (MgO) is produced. Magnesia is also produced synthetically from seawater and natural brines. Caustic magnesia is used as the prime feedstock for the production of electrofused magnesia, in the chemical and pharmaceutical fields, as a filler in plastics and paints, in the paper industry, as a fertiliser and animal feedstuff, for water clarification, in pollution control and in many other fields. The current product specifications are as varied as the end use of the material.

Dead Burned Magnesia When caustic magnesia is burnt at higher temperatures (1800°C) a non-reactive dense material known as dead burned or sintered magnesia (MgO) is produced. This is used as the primary base material for heat-containment refractories for lining steel furnaces and other kilns used in high temperature applications such as cement production, glass making, and copper smelting. The 1997 world market was about 6.3 million tonnes/year. Magnesia used in refractory applications commonly has more than 90 per cent MgO, though the specifications for high quality material include: Component

Specification

MgO

>96%

CaO:SiO2 ratio

>2

Fe2O3

>0.5%

B2O3

<0.5%

R2O3

<1%

Bulk density

>3.4 DIN

Periclase crystal size

>100 µm

Free lime particles

Nil

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MANGANESE World production in 1998 was about 22.1 million tonnes of manganese ore, of grade 25-52 per cent manganese. The 1998 production included about 1.5 million tonnes of lump ore from Groote Eylandt, with 48 per cent Mn, that sets the world benchmark for sales of high grade ores. There are more than 100 manganese minerals, but the common ore minerals are mixtures of manganese oxides (MnO2, nominally 63 per cent Mn). The usual field terms are psilomelane for a hard massive mixture of oxide minerals, pyrolusite for a soft black earthy mixture, and wad for impure, brown earthy oxides and hydrated oxides. The ore minerals at Groote Eylandt are largely pyrolusite and cryptomelane. Manganiferous iron ores, with >five per cent Mn, are often attractive for blending in iron smelting. Deposits of manganese oxides, containing copper and nickel, are known in parts of the deep ocean floor, and these may be a significant future source. Manganese orebodies are generally selectively mined in open pits, and shipped after crushing and gravity separation in some cases; beneficiation by flotation is technically possible. About 90 per cent of the world output is used in the steel industry, and manganese is an important constituent of several nonferrous alloy systems, principally aluminium alloys. This metallurgical grade ore is required to have a minimum of 46 per cent Mn (with a premium for 50 per cent ores), SiO2 maximum eight per cent, Fe maximum 8.5 per cent, and P maximum 0.18 per cent. The remainder is used for manganese chemicals and in the manufacture of dry cell batteries. This chemical or battery grade should contain a minimum of 70 per cent MnO2 and a maximum of two per cent FeO. It should also be practically free of Cu, Sb, As, Ni, Pb and Co. Manganese ore prices are quoted in $US per tonne unit of Mn, ie per one per cent of contained Mn per tonne of ore or concentrate.

MERCURY Total world production and consumption in 1998 were estimated to be about 2600 tonnes. World trade is quoted in flasks of 34.5 kg net weight of Prime Virgin Mercury, which contains more than 99.99 per cent mercury and less than 1 ppm of any base metal. Mercury of higher purity is produced by multiple distillation or electrolytic refining, and commands a premium over the standard grade.

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MINING AND ECONOMIC GEOLOGY

The only important ore mineral is cinnabar (HgS, with 86 per cent Hg), which is generally associated with minor amounts of native mercury and the chloride, calomel. The larger producers include Spain (from the historic Almaden mines), Algeria, Kyrgyzstan and China, and the industry has excess production capacity. About 10 000 flasks of byproduct mercury were obtained in 1997, from treatment of gold and silver ores. There are potentially large supplies of secondary mercury, obtained by dismantling of chlorine-caustic soda plants that are being changed to a mercury-free process. World primary resources are estimated to be nearly 240 000 tonnes of mercury, equal to about 90 year’s consumption at the 1998 rate, and many mines have closed in recent years. There is no current Australian production. Ore treatment is by simply roasting the ore and condensing the vapour, which is run into storage tanks. Sales are quoted in $US per flask for 50 flask lots.

MICA AND VERMICULITE World production of mica was about 250 000 tonnes in 1998, including about 5500 tonnes of premium grade sheet mica. This is used in the electrical industry as an insulator, but the demand is erratic, and supply equally so, with substitution of ‘plastic’ sheeting a constant threat to natural mica production. Only muscovite and phlogopite are commercially important as sheet mica, and are classified as ‘ruby’ mica when tinted brown and ‘non ruby’ when transparent. The remainder is flake or scrap mica Sheet mica is hand mined, largely from pegmatite deposits, and trimmed into sheets. Small producers hand sort the trimmed sheets into a range of thickness sizes, viz: Block: not less than 0.10 inches (2.54 mm) thick. Film: between 0.10 and 0.0012 inches (2.54-0.03 mm) thick. Splittings: less than 0.0012 inches (0.03 mm) thick. Larger producers may split film and block mica into a standard thickness required by the purchaser, with the thickness specified in mils (thousandths of an inch), eg 2/3 mil film is all between 0.002 and 0.003 inches thick. Sheet is sold by the pound, with a premium for clear (non-ruby) mica, and for sheets with a large surface area. The minimum surface size for individual sheets to be suitable for industry requirements is about 25 mm square. A high heat resistance (ie high fusion temperature) is important in some applications. Scrap mica, rejected from trimming the larger sheets, and obtained from finer grained deposits, is sold by the tonne at a much lower price than sheet.

Vermiculite is hydrated altered mica, which expands on heating with a very large increase in volume. World production was about 440 000 tonnes in 1998, with the Palabora deposit in Transvaal and the W R Grace and Co. mines in Montana and South Carolina the largest sources. Australian Vermiculite Industries Pty Ltd started production from the Mud Tank deposit, about 160 km northeast of Alice Springs, in 1995, and estimates that 1998 output will be about 16 000 tonnes. The mine product may be beneficiated by flotation, and sized. There is a premium for particles of diameter greater than 20 mm, although sizes down to 1 mm are saleable. The Mud Tank operation is using wind tunnel technology to sort the product into several grades. Vermiculite is sold and transported unexfoliated, with a bulk density of about 1. It is then processed (at or near the point of final sale) at about 2500°C to cause exfoliation and a decrease in bulk density to about 0.1. Crude unexfoliated vermiculite is generally sold in bulk, with international trade quoted as $US per tonne.

MOLYBDENUM World consumption of molybdenum metal in concentrates was estimated to be about 250 million pounds (about 114 000 tonnes) in 1998. The only significant ore mineral is molybdenite (MoS2, with 60 per cent Mo). Oxidised minerals, mainly ferrimolybdite (hydrated iron-molybdenum oxide) and wulfenite (lead molybdate) are the principal weathered zone products of primary molybdenite deposits; these oxidised minerals are generally not recovered. Molybdenum is generally used in industry as the mineral, although some is converted to alloys and chemicals. There are five established, molybdenite-only producers (Table 16), all in North America. By- and co-product molybdenum supply in 1997 was about 61 million kilograms, obtained by mining of porphyry copper-molybdenum deposits in the western US and China. A further 13 million kilograms of unknown origin was traded by China. TABLE 16 North American molybdenite production. Mine

Annual capacity, M kg Mo

1997 production, M kg Mo

Climax

0.3

9.1

-

Henderson

0.42

45.4

13.6

Thompson Ck

0.18

8.2

8.2

Endako

0.12

6.3

6.3

Questa

0.15

6.3

3.2

75.3

31.3

TOTAL

110

Av. head grade,% MoS2

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MINING AND ECONOMIC GEOLOGY

Molybdenite is very amenable to flotation, usually with high recovery. Mixed ores may require several flotation stages to remove other sulphides to an acceptable level in the molybdenum concentrate. Minimum saleable concentrate grade is 85 per cent MoS2, with a premium for 90 per cent and 95 per cent grade, and maximum impurity levels of 0.05 per cent Cu, 0.3 per cent Pb and 0.1 per cent P. Concentrates are sold on a basis of $US per pound of contained molybdenum.

NICKEL Estimated world mine production was about 1.17 million tonnes in 1998, including about 140 000 tonnes from Australian mines. Approximately half of the world production was from sulphide ores, and half from laterite (oxide) ores. Australian mine production may increase by 60 000-70 000 tonnes per year when the Murrin Murrin, Cawse and Bulong laterite mines and pressure leach plants come on stream in 1999. Laterite deposits have potential to produce low-cost nickel due to cheap open pit mining, low pressure-leach operating costs and extraction of byproduct cobalt. Treatment of these nickel-cobalt ores is described under cobalt. The principal sulphide ore mineral is pentlandite, an iron-nickel sulphide with a maximum of 34 per cent nickel. Pentlandite is practically always associated with pyrrhotite and pyrite, and other associates are chalcopyrite, cobalt as linnaeite or in solid solution in iron sulphides, and minor nickel sulphides such as millerite, niccolite and gersdorffite. Precious metals are a significant constituent in some pentlandite ores. Typical sulphide ore grades and recoveries from producing deposits in WA are shown in Table 17. TABLE 17 Production data for major WA nickel mines, 1996-97 year. Mine details

Ore milled

Product

Recovery

Kambalda group u.g., WA

1.16 Mt at 3.05 % Ni

32 329 t Ni in conc.

91.4 %

Leinster group u.g., WA

2.01 Mt at 2.23 % Ni

38 007 t Ni in conc.

84.8 %

Mt Keith o.c., WA

9.39 Mt at 0.60 % Ni

34 111 t Ni in conc.

60.5 %

Sulphide ores can be concentrated by flotation. A bulk sulphide concentrate is first obtained, and the grade of this is dependent on the pentlandite:pyrrhotite ratio of the ore. Other minerals commonly reporting in the concentrate are talc and tremolite. Some concentrates can then be differentially floated to

Field Geologists’ Manual

produce a high nickel (pentlandite) concentrate, a copper concentrate and a pyrrhotite tailing. Cobalt normally reports in the nickel concentrate. If nickel occurs in solid solution in pyrrhotite or pyrite, some may be lost. Nickel concentrates contain from eight to 18 per cent nickel, with the commonest ten to 13 per cent nickel. Processing is by roasting, smelting, converting and refining as at Kambalda, described in Woodcock and Hamilton (1993, pp 1199-1202), or by the Sheritt Gordon leach process, as at Kwinana (ibid, pp1203-1208). In the first process, during the roasting the concentrates are heated in air, driving off sulphur dioxide and converting the metals to oxides. In the Outokumpu flash smelting process the roasting stage is simultaneous with smelting. Smelting furnaces (blast, reverberatory, flash or electric) convert the roasted feed to a matte, in which the gangue and nearly all the iron have been eliminated. Bessemer converting produces a high grade matte, typically assaying 70 to 75 per cent Ni, less than one per cent Fe, less than one per cent Co, nil Cu, 20 per cent S, and containing the precious metals. Refining of converter matte is by electrolysis, by vapormetallurgy (Inco process) or by the Sherritt Gordon hydrometallurgical process. A large proportion of the nickel ores are converted to ferro-nickel and sold in this form to steelworks. Penalty metals and minerals are: Magnesia is the major problem, as it increases the melting point of the slag in smelting. Generally a penalty is payable for > five per cent MgO in flotation concentrates. Lead, zinc, arsenic, antimony and bismuth are undesirable, and the sum of these metals in a concentrate should not be greater than 0.5 per cent. Copper - the Ni:Cu ratio may be important, depending on the copper removal facilities in the processing stages. The remaining production of nickel is from ‘silicate’ or ‘oxide’ nickeliferous laterite ores. The silicate ore minerals are nickeliferous hydrated silicates (including serpentine, saponite, nontronite, talc, pimelite and chlorite in decreasing order of importance), while the oxide ore minerals are nickeliferous limonite, and nickel bearing ferromanganese oxides, notably lithiophorite. The silicate minerals generally occur near the saprolite base of lateritic weathering profiles, and they occur both as metasomatic alterations of pre-existing bedrock minerals (especially serpentine and nontronite) or as precipitated phases in bedrock fractures and joints. The latter tend to have high nickel grades (ten per cent), a strong green colour, and are often grouped under the field name ‘garnierite’. Silicate ores can be beneficiated or upgraded in some instances by trommel screening to remove hard residual bedrock cores, or in some instances by crushing and removal of secondary quartz. Typical saprolite-ore grades range from 1.5 per cent to three per cent Ni.

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MINING AND ECONOMIC GEOLOGY

At a higher level in the weathering profile, the limonitic ores with accessory ferromanganese minerals rarely exceed two per cent Ni and 40 to 48 per cent Fe. Most of the oxidised ores, as mined, contain ten to 40 per cent water, and drying requires considerable fuel. Laterite nickel ores generally have an ore grade of one to two per cent Ni. The gangue composition is significant in the terms of its acid or alkali solubility in the pressure leach process, and the high Mg clays such as nimites that are acid consumers involve higher leach charges. Deep ocean floor manganese-nickel oxide nodules may contribute to future production if a satisfactory ‘mining’ method can be developed, the economics improve, and the political’ problems are solved. All nickel sales are per pound of product, available as 99.9 per cent Ni pellets and five pound bars, as 75 per cent or 90 per cent Ni in sintered oxide powder or briquettes, and as ferro-nickel ingot of several grades and weight.

NIOBIUM (COLUMBIUM) and TANTALUM World production was around 65 million pounds (29 500 tonnes) of contained niobium pentoxide in 1998. Consumption of niobium grew at about 20 per cent per year in the 1990s, due to its increasing use in high strength low alloy (HSLA) steels. World demand for tantalum also grew strongly, and reached 3.83 million pounds (1737 tonnes) of contained tantalum in 1999. The price of tantalum in concentrates is typically ten times that of niobium in concentrates. Niobium (Nb, equivalent to Cb for columbium in older publications) is produced principally from pyrochlore [(Na,Ca)2(Nb,Ta)2O5(OH,F)], containing up to 65 per cent Nb2O5, which occurs in carbonatite intrusions and is mined mainly in Brazil and Canada. The Araxa pyrochlore deposit in Minas Gerais state in Brazil, with an ore reserve of around 500 million tonnes of ore averaging 2.5 per cent Nb2O5, produced around 75 per cent of the world’s Nb in concentrates in 1997. Tantalum and minor niobium are produced as a coor by-product of tin mining from the mineral series tantalite-columbite. The series has a general formula (Fe,Mn) (Nb,Ta)2O6, with tantalite containing up to 86 per cent Ta2O5 and columbite containing up to 78 per cent Nb2O5. Tantalum and niobium are produced from tantalite-columbite mineral concentrates, or recovered by treatment of some tantalum-bearing tin slags. Tantalite-columbite minerals occur in pegmatites and veins, with deposits typically grading around 0.05 per cent Ta2O5 and 0.04 per cent Nb2O5, although the Nb:Ta ratios vary widely. These pegmatites occur at Greenbushes, around Kalgoorlie and in the Pilbara region, all in WA, and in the Bynoe Harbour area in NT. Tantalum and niobium

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occur in the Mount Weld carbonatite and in the Mount Brockman rare metals deposits, both in WA. Australian and world tantalum production in 1998 was dominated by Sons of Gwalia Ltd, from open cuts at Greenbushes (production 272 tonnes of Ta2O5 in concentrates) and Wodgina (Pilbara, 62 tonnes of tantalite concentrates). Tantalum and niobium demand and prices have fluctuated widely over the last decade. Although specifications vary slightly between markets, pyrochlore concentrates are based on a 57-62 per cent Nb2O5 range, and columbite concentrates require a minimum 65 per cent Nb2O5 + Ta2O5 content and a ten to one ratio of Nb2O5 to Ta2O5. Prices are quoted as $US per pound of pentoxide. Tantalum concentrate prices are quoted for two grades of concentrate: low grade with five to 40 per cent Ta2O5, quoted on the basis of 30 per cent Ta2O5, and high grade with minimum 60 per cent Ta2O5. All prices are in $US per pound of contained pentoxide. Buyers require a maximum U3O8+ThO2 content of 0.5 per cent. Apart from market prices, some tantalum and niobium concentrate operations quote producer prices.

PHOSPHATES Phosphatic fertiliser may be naturally occurring phosphate rock and apatite, guano and cave earth of organic origin, and basic slag (the slag resulting from basic open-hearth steel production). Phosphate rock is by far the most important source, with world mine production about 141 million tonnes in 1998. This rock is usually very fine grained, in which the phosphate mineral is one of the members of the fluorapatite-chlorapatite-hydroxylapatite series, with general formula Ca5(PO4,CO3)3(F,OH,Cl). The major constituents in apatite are CaO, zero to 55 per cent, and P2O5, 38 to 42 per cent. The term collophane is used for the cryptocrystalline variety of apatite. Rock phosphate grades are quoted as per cent P, per cent P2O5 or as per cent TPL or per cent BPL (tri-phosphate of lime or bone phosphate of lime, equivalent to 2.185 × per cent P2O5). Phosphate raw materials for the Australian market were historically supplied by open cut workings on Christmas, Nauru and Ocean islands, but these sources are now largely depleted. The supply in 1998 was drawn from Algeria, Morocco, Nauru and the US; typical analyses are shown in Woodcock and Hamilton (1993, p 1398). Resources in the Mount Isa district held by WMC Holdings Ltd are being developed, and will be a significant contributer to the Australian market from 2000. These resources exceed 2000 million tonnes of average grade about 17 per cent P2O5, including about 40 million tonnes of direct shipping grade (about 31 per cent P2O5) Typical phosphate rock analyses for the historic sources (Woodcock, 1980, p 656) are shown in Table 18.

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TABLE 18 Historic guano-type phosphate rock specifications. Component

Nauru Island

Christmas Island

Ca3(PO4)2, or ‘TPL’

82.8

82.3

P2O5

37.9

37.7

Fe2O3

0.16

1.32

Al203

0.14

3.10

F

2.9

1.4

SiO2

0.10

0.15

A wide range of phosphorus chemicals is made from rock phosphate, but only the manufacture of superphosphate, the principal usage of phosphate rock, is considered here. There is at least one superphosphate plant in each of the six States. For single superphosphate the crushed rock is treated with sulphuric acid, producing calcium sulphate and water soluble mono-calcium phosphate. In the production of triple or high analysis superphosphate, the calcium sulphate is removed (as gypsum) from the product. Penalties are applicable to phosphate rock with a significant content of sulphuric acid consuming minerals, such as free calcium carbonate, iron oxides and alumina. The presence of a wide variety of metals and halogens (particularly fluorine) above minimal level is undesirable. Sales of phosphate rock are generally by annual contract with consumers, with minimum grades about 30 per cent P2O5 (about 66 per cent TPL), and a premium payable for high grade rock of analysis 32.5 to 35 per cent P2O5 (70 to 77 per cent TPL).

PLATINUM GROUP The platinoids, platinum group elements (PGE) or platinum group metals (PGM) comprising platinum, palladium, iridium, osmium, rhodium and ruthenium are all silvery metals with high density. There are more than 100 named PGE minerals, plus more than 100 numbered, but not named minerals that have not been properly characterised. The PGE minerals include natural alloys with many elements, sulphides, arsenides, selenides and tellurides. Free world consumption in 1997 was about 174 tonnes (5.6 million ounces) of platinum, 254 tonnes (7.9 million ounces) of palladium, 15 tonnes of rhodium, ten tonnes of ruthenium, and one tonne each of iridium and ruthenium. The major PGE producers were South Africa (providing 70-80 per cent of the worlds mine production, from ten operations in the Bushveld Complex), Russia, and Canada. The principal sources

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are primary deposits of PGE (South Africa), by-product production from nickel and copper-nickel deposits (Canada and Russia), and alluvial deposits in Colombia and Russia. Because all of the PGE are recovered from any deposit, there is little control of the level of production of individual PGE, which leads to marketing problems and price variations. Primary PGE ores are treated by fine grinding and then flotation, to recover a mixed nickel-copper sulphide concentrate containing the PGE. This concentrate is treated by hydrometallurgical methods to remove the copper and nickel, with the residue containing the PGE sent to a refinery, or by smelting the copper-nickel-PGE concentrate to a matte that can be sent to a refinery. High chromite levels that occur in some ores can interfere with some smelting processes. Almost all nickel sulphides contain traces of PGE, with the Sudbury pentlandite ores (the largest source of byproduct PGE) averaging about 0.8 g/t PGE, of which about half is platinum. These normally report in the nickel matte produced in the smelting process, and in electrolytic refining the PGE (and gold) report in the anode sludge, from which they can be recovered. Custom smelters using electrolytic refining methods normally make a payment for part of the precious metals in concentrates, but only if each of platinum and palladium exceeds about 2 g/t. World PGE resources are about 70 000 tonnes (2250 million ounces), with the greatest concentration in the Bushveld Complex. PGE producers are notably secretive about production and reserve information. However, Aquarius Platinum NL stated in 1999 that they were planning underground mining at the U2 Reef at Kroondal, in the Bushveld Complex, at an annual rate of 1.2 million tonnes of ore at an insitu head grade of 5.5 g/t PGE. Recovery was expected to be 165 000 ounces of PGE per year, equivalent to a recovered grade of 4.3 g/t. The only significant Australian production is from the Kambalda nickel sulphide ores, in which the sulphides contain 0.5-1.5 g/t Pt and 1-3 g/t Pd. All the PGEs are sold as refined metal, with prices quoted in $US per troy ounce.

POTASSIUM World production was about 24.9 million tonnes of contained K2O equivalent in 1998. Australian imports of fertiliser-grade potassium chloride and sulphate were about 432 000 tonnes in 1997-98, containing about 259 000 tonnes of potassium. About 70 per cent of world production is from mines in Canada, Russia and Belarus, and these areas have huge resources. The principal potassium ore minerals are sylvite (KCl, equivalent to 63 per cent K2O) and carnallite (KMgCl3.6H2O, equivalent to 16.8 per cent K2O). Other important ore minerals are polyhalite, with about 15 per cent K2O, kainite, with about 19 per cent K2O,

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and langbeinite, with about 22 per cent K2O. All occur as natural mixtures with halite (the sylvite-halite mixture is known as sylvinite) and all are confined to salt lake and evaporate sequences. A general rule for underground mining is a minimum grade of 14 per cent K2O in a bed at least 1.2 metres thick, with a salt roof thickness of >8 metres (Carr, 1994). The only significant hard rock potash source is alunite, with about 11 per cent K2O. The Canadian deposits occur in a 100 metre thickness of the Middle Devonian Prairie Formation of Saskatchewan. Three potash rich beds (as sylvinite and carnallite) are known in this thickness, with commercial potash grades 25 to 35 per cent K2O. Reserves to a mine depth of 1100 metres of this grade, in beds 1.5 to 3.0 metres thick, have been calculated as 6400 million tonnes. Mining is generally by large diameter face boring machines, coupled to continuous conveyors, but at one mine the ore is removed by water solution from beds at over 1500 m depth. In either method, sodium chloride is precipitated from concentrated solutions and the residual liquor is fed to a crystalliser to deposit the potash (Little et al, 1970). The varied ore types provide a range of saleable potassium salts. The sylvite ores are sold on a minimum basis of 60 per cent K2O, and are used for fertiliser and general chemical manufacture. The chloride product, derived from mixed carnallite-sylvite ore is used as fertiliser; and the sulphate product of minimum 50 per cent K2O (from kainite and langbeinite ores) commands a premium over the others. Prices are quoted in cents per unit of K2O content.

RARE EARTHS and THORIUM The rare earth elements (REE) are not particularly rare, being a family of metals with atomic numbers 58 to 71. The elements scandium (21), yttrium (39), lanthanum (57) and thorium (90) usually occur with the rare earths, and are commonly included with them. World production of rare earth concentrates in 1998 contained about 66 500 tonnes of rare earth oxides (REO), of which China supplied more than 70 per cent. The elements with atomic numbers 57 to 71 are chemically and geochemically similar, and may be collectively considered as a single element, variously known as lanthanon or the lanthanides. They have been grouped in several ways. The members of the light, ceric or LREE subgroup are lanthanum (57), cerium (58), praseodymium (59), neodymium (60), promethium (61), samarium (62), and europium (63). Gadolinium (64), terbium (65), dysprosium (66), holmium (67), erbium (68), thulium (69), ytterbium (70) and lutetium (71) comprise the heavy or HREE subgroup. The addition of yttrium (90) to the HREE produces the yttric sub-group. The gadolinite earths are the yttric subgroup plus scandium (21).

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Jones et al (1995) list about 250 RE minerals, but production of RE is dominated by five. These are: Monazite is basically (RE,Th)PO4, containing about five to 30 per cent ThO2, 28 per cent Ce2O3, other REO 32 per cent and 28 per cent P2O5. Most monazite is won as a byproduct of alluvial mining, the Australian east coast beach sand monazite concentrate containing about 6 per cent ThO2. It contains largely light REE. Bastnaesite comprises (Ce,La)CO3(F,OH) with principal sources byproduct concentrates from iron ore mining at Bayan Obo in Inner Mongolia, and the principal product from the Mountain Pass deposit in California. It is a major source of light REE. Xenotime, obtained as a byproduct of mineral sands and alluvial tin mining, is a major source of yttrium and the heavy REO. It is a source of heavy rare earths. The WIM 150 deposit (Rio Tinto Ltd), near Horsham in Victoria, contains large xenotime reserves. Loparite is a calcium-cerium-sodium titanate, perhaps (Na,Ce,Ca)2(Ti,Nb)2O6, principally mined from the Kolar peninsula in Russia. Ion absorption clays are only known from China. They were formed by secondary concentration of REE in the weathering profile developed on granites. In these deposits the REE are loosely held by ion absorption on clay particles – and are readily extracted from the host by simple hydrometallurgical processes. The deposits are preferentially enriched in mid-range REE, principally samarium and europium from the LREE class and gadolinium and terbium from the HREE. Primary deposits containing bastnaesite, xenotime, gadolinite, euxenite, samarskite, fergusonite, davidite and thorianite (often associated with uranium mineralisation) provide ample alternative sources, and world reserves are about 100 million tonnes of REO. In beach sand or other alluvial mining, monazite reports in the heavy mineral concentrate. It is weakly magnetic and non-conducting, with a higher density than zircon, rutile or ilmenite. The primary separation is by electrostatic methods, which produce a garnet-tourmaline-monazite fraction, with minor zircon, which is cleaned by air tabling and further magnetic separation. There was no Australian monazite concentrate production in 1998. Cracking of monazite requires solution in hot concentrated sulphuric acid, but other acid consuming minerals increase costs, and lower the concentrate sale price. Monazite can also be cracked using caustic soda. Rare earths are precipitated by oxalic acid from an acid solution, then separated by a range of fractional precipitation and crystallisation processes. The fused anhydrous chlorides from monazite are known as ‘mischmetall’ (mixed metals), which is a blend of the rare earths in monazite. Mischmetall is about 50 per cent cerium, 40 per cent lanthanum + samarium + neodymium + praseodymium, and about ten per cent yttrium + iron.

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Sales of monazite concentrates, with minimum 60 per cent (REO + ThO2) are quoted per tonne. Bastnaesite concentrates with minimum 70 per cent REO are quoted per pound of contained REO and xenotime concentrates with minimum 25 per cent REO are quoted per pound of contained Y2O3. For further information on rare earths in commerce see Gschneidner and Eyring (1978), Henderson (1983), Jones et al (1995), McCarthy and Rhyne (1978) and Xu Guanxian and Xiao Jimei (1985)

RHENIUM Estimated 1997 world production of rhenium was about 18.7 tonnes, with installed capacity 47.3 tonnes. Most rhenium is produced as a byproduct from traces in molybdenite in porphyry copper deposits, and recovered from flue gases and dusts obtained by roasting molybdenum concentrates. There has been minor production of rhenium from traces in copper ores, from a copper-rhenium mineral in Kazakstan, from uranium-molybdenum ore in the US and from molybdenum-tungsten ore in Russia. Rhenium mineralogy is obscure, but several sulphides and an oxide are known to exist. Molybdenite may contain up to 3000 ppm Re, and rhenium is known at trace levels from a number of base metal sulphide and coal deposits. Western world reserves recoverable with current technology are estimated at 350 tonnes. The price for rhenium metal powder of grade 99.9 per cent Re is quoted in $US per pound.

RUBIDIUM The world demand for rubidium is small, probably less than 1000 kg/year. This is easily provided by recovery as a byproduct of processing caesium and lithium ores, and from carnallite; the carnallite from one German mineral-spring deposit contains 200 ppm RbCl. Rubidium occurs in most potassium salts and minerals, and in plants, seaweed and seawater.

SELENIUM Estimated world selenium production was about 1660 tonnes in 1998. There is a wide range of selenium-bearing minerals, and although no commercial deposits are known, the selenides associated with base metal sulphides are a valuable bonus with some deposits (particularly at Tennant Creek). The metal is largely obtained as a byproduct from electrolytic refining of copper and nickel ores, where it occurs as trace elements in other sulphides, and reports in the anode slime. Sales are quoted in $US per pound for minimum 99.9 per cent Se, with a premium for high purity (99.99 per cent Se) metal.

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SILICA Silica sands and gravels are used in very large volumes in the construction industry, but this trade is not discussed herein. The major other uses of silica are in glass making, in silica refractories used largely in open hearth steel plants and in copper smelting, and in manufacturing silicon and silicon alloys. Annual Australian usage is unknown, but is probably several hundred thousand tonnes of high-purity silica sand for glass making (excluding exports). About 250 000 tonnes/year of silica are quarried for metallurgical flux and for manufacturing silicon and silicon alloys. Australian export silica operations have been established at Cape Flattery (Qld), with capacity of about a million tonnes per year, and at Kemerton (WA), with a capacity of about 400 000 tonnes per year. The average quality of the Cape Flattery product is: Component

Analysis, %

Particle diameter, µm

%

SiO2

99.82

+425

2.66

Al2O3

0.05

+300-425

10.07

Fe2O3

0.01

+212-300

32.27

CaO

0.01

+150-212

47.58

MgO

0.01

+106-150

7.34

TiO2

0.02

-106

0.08

LOI

0.10

Grain Fineness No: 61.7

The specifications for glass sand (Woodcock, 1980, p 694) are a grain size such that 90 per cent lies between 36 and 120 BSS mesh, and for white sand (for clear glass) a minimum of colouring materials eg max. 0.025 per cent Fe2O3, and max. 0.0002 per cent Cr2O3. Amber sand used for coloured glass should contain less than 0.1 per cent Fe2O3 and less than 6 ppm Cr2O3. These specifications are often obtained by flotation to remove iron minerals and removal of the minus 106 µm slime particles.

SODIUM Developed countries use naturally occurring sodium chloride (common salt) and sodium carbonate (soda ash) as feedstock for their chemical industries. World production of natural sodium raw materials in 1998 was about 200 million tonnes of common salt and ten million tonnes of soda ash. The evaporite deposits mostly contain halite (common salt) associated with the carbonates, sulphates, borates and halides of sodium, potassium, calcium and magnesium. These may occur as relatively pure, thick deposits or as thin layers mixed with detrital sediments, organic material, iron oxides and sometimes

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barite and magnesite. The common evaporate minerals are sylvite KCl, halite NaCl, carnallite KMgCl3.6H2O, kainite MgSO4.KCl.3H2O, langbeinite K2Mg2(SO4)3, polyhalite K2Ca2Mg(SO4)4.2H2O, thenardite Na2SO4, anhydrite CaSO4, gypsum CaSO2.2H2O, kieserite MgSO4.H2O, trona Na2CO3.HNaCO3.2H2O, calcite CaCO3, aragonite CaCO3, dolomite (Ca,Mg,Fe)(CO3)2, kernite Na2B4O7.4H2O, borax Na2B4O7.10H20, ulexite NaCaB5O9.8H2O and colemanite Ca2B6O11.5H2O. The major Australian producers use solar evaporation of seawater or borehole brine. Production in 1997 was 850 000 tonnes from Dry Creek (SA); plus 2.7 million tonnes from Cargill, 3.44 million tonnes from Dampier, 1.11 million tonnes from Lake Macleod and 930 000 tonnes from Useless Loop, all in WA. Critical components quoted in a commercial product are NaCl, Ca, Mg, K, As, I, insolubles and heavy metals (particularly Cu and Fe).

STRONTIUM World production was about 300 000 tonnes of celestite in 1997. Nearly all of the celestite (SrSO4) was converted to strontium carbonate and used to make TV tubes, with a little used as a filler. Minimum celestite concentrate grade is 90 per cent SrSO4; further details are in Griffith (1996, pp 32-33).

SULPHUR World production of sulphur in all forms was estimated as about 54 million tonnes in 1998, of which about 70 per cent was as brimstone (elemental sulphur) and the remainder was byproduct sulphur. About 90 per cent of the brimstone was obtained by recovery of H2S in sour natural gas or sour crude oil. Wells in western Canada, Russia and the US were the largest suppliers. This sour gas byproduct sulphur is generally the cheapest available, and must be transported in liquid form (due to anti-pollution regulations); combined with transport costs it forms a floor price with which all other sulphur producers must compete. The remaining ten per cent of the brimstone was obtained from bedded sulphur deposits, which are mined underground or melted by the Frasch process, with some minor production from caliche or anhydrite. Deposits of native sulphur are generally of Tertiary age or younger, interbedded with gypsum and anhydrite marl, and contain around 20 per cent S to be of ore grade. The byproduct world production was as sulphur dioxide gas, largely used in the manufacture of sulphuric acid. Major sources are roasting of pyrite (53.5 per cent S), and as a byproduct in smelting non-ferrous ores - largely those containing chalcopyrite (35 per cent S), galena (13.4 per cent S) and sphalerite (33.1 per cent S). Pyrrhotite, gypsum, anhydrite and

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alunite have been used in special cases, and reduction of ferrous sulphate waste from other processes is theoretically possible. About two-thirds of the Australian sulphuric acid production is made from imported brimstone and the remainder from roasting locally derived sulphides. Brimstone is sold by the long ton, and is available in liquid or solid form. Dark sulphur has a particle size to several cm diameter, and is lower grade than bright sulphur, which is uniformly fine yellow powder, and commands a premium.

TALC, STEATITE and PYROPHYLLITE World production of talc-family minerals was about six million tonnes in 1997. Australian production was about 207 000 tonnes, from operations at Mount Fitton, SA (12 000 tonnes), Mount Seabrook, WA (25 000 tonnes) and Three Springs, WA (170 000 tonnes). Although the minerals talc, Mg3Si4O10(OH)2, and pyrophyllite, AlSi2O5(OH) are different, they have similar properties and mode of occurrence. Steatite is a high grade ‘soapstone’ and is essentially composed of talc. If the grade is particularly low it is simply a talc schist. Talc is generally white and purer if it has been derived from metamorphism or hydrothermal alteration of sedimentary magnesium carbonates than from igneous ultrabasic rocks. The major Australian producer is Three Springs Talc Pty Ltd (Western Mining Corporation Limited) which operates an open pit mine and beneficiation plant at Three Springs, about 340 km north of Perth. Ore is crushed, screened and hand sorted to remove low grade material, and shipped through Geraldton. The main determinants of grade are purity and colour (whiteness). Of the physical properties the whiteness is often the most critical, but oil absorption and density are also relevant. The specific properties that make talc desirable for a wide variety of industrial uses and which should be determined include the following: extreme whiteness, excellent softness and smoothness, fibrous or flaky component particles with large surface area in relation to the mass, good hiding power, excellent suspension, good lustre or sheen, high ‘slip’ or lubricating power, specific types of water, oil and grease absorption, chemical inertness, high fusion point, low shrinkage, low electrical and thermal conductivity, high dielectric strength, high specific heat, resistance to heat shock, and good retention for filler purposes. The relative importance of these properties varies with the purity and fabric of the ore, and the dressing method. Note that if it is to be used in toilet preparations the Pb content of the milled talc must be below those limits set by the Toilet Preparations Federation (London) in Specification No. 12. After milling no more than two per cent should be > 75 µm so a particle size analysis is also necessary.

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A mineralogical examination is needed to determine the presence of other magnesium minerals besides talc (eg tremolite, magnesite, dolomite, chlorite and serpentine) and the presence of impurities such as chromite, quartz, calcite, and iron oxides. This study can indicate the grain size for grinding tests, and the shape of the talc particles (ie platy, fibrous or granular), which influences the properties of the processed material and therefore its potential uses. Chemical analyses determine the purity and the following must be reported: SiO2, MgO, Fe2O3, FeO, Al2O3, LOI and perhaps CaO, MnO2, K2O and Na2O. Commercial Minerals Ltd. of Sydney are able to quote specifications, prices and uses for various grades of ore. In general, however, the following apply: G.E. whiteness 86; SiO2 60 to 65 per cent; free silica three to five per cent; MgO 28 to 32 per cent; Fe2O3 one per cent; Al2O3 four per cent; LOI about five per cent.

TELLURIUM Estimated 1998 world production was 250 tonnes, from installed capacity of about 500-600 tonnes. Gold, silver, lead, bismuth, mercury and copper tellurides occur as important constituents in a number of ore deposits, and tellurium is recovered from anode slimes during the refining of these, largely from the copper, nickel and lead tellurides. Prices are quoted in $US per pound of tellurium metal of grade 99.8 per cent Te.

THALLIUM Thallium occurs at trace levels in potassium feldspars, in galena and other sulphides, in a variety of lead sulphosalts and in potassium salts. Commercial thallium is obtained as a byproduct of smelting lead-zinc ores, and from the roasting of pyrite for sulphuric acid production. Ample reserves are available in some thallium-rich arsenical gold ores.

TIN World mine production of tin in concentrates was about 216 000 tonnes in 1998. The principal ore mineral is cassiterite (SnO2, with maximum 78.6 per cent Sn), with minor production from stannite (tin-copper-iron sulphide) deposits. Iron may substitute for tin in cassiterite to a maximum of about Fe:Sn = 1:6, and tantalian varieties are known, with (Ta,Nb):Sn up to 1:30. Cassiterite has a high density (6.8-7.1) and is reasonably resistant to abrasion, thus alluvial deposits are an important source. Alluvial ore grades were historically quoted as ounces and pounds (avoirdupois) of tin per cubic yard, with the metric usage grams and kilograms per cubic metre. Sampling of alluvial tin deposits is usually empirical, and pit or drillhole samples are usually ‘assayed’ by simple gravity separation methods. This provides recoverable cassiterite values, achievable in a typical commercial plant, and not the total cassiterite present; the very

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fine-grained ‘slime’ cassiterite is usually lost in this sampling-assaying method. Thus the recovery quoted in production reports may be greater than 100 per cent, and is generally meaningless in terms of the ‘total’ or ‘geological’ resource. Typical grades for very large deposits, suitable for dredging, are a few ounces of tin per cubic yard (about 200 g/m3) - this is probably a minimum recoverable ore grade at a mining rate of six million cubic metres per year. Smaller and higher-grade deposits are worked by bulk earthmoving equipment. For this method, minimum orebody sizes are in the range one million cubic metres at 1 kg per cubic metre to ten million tonnes at 0.5 kg per cubic metre. Treatment of alluvial ores is by trommels or vibrating screens, followed by jigs or other gravity separation equipment. The crude concentrates are cleaned on a Wilfley table, or in a streaming box for small operations. Other valuable heavy minerals, particularly gold, are recovered at this last stage. Tin recovery reaches about 80 per cent for clay-free, clean, well sorted alluvials, with concentrate grades to 76 per cent Sn. Recovery diminishes to less than 50 per cent in deposits with very fine cassiterite grains and significant proportions of clay, with concentrate grades 65 to 70 per cent Sn. In hard rock deposits, average ore grades are about minimum 0.2 per cent Sn for large open cut workings, about 1.0 per cent Sn for large underground mines and two per cent Sn for small underground operations. The ore is crushed and pulverised, and associated sulphides are removed by flotation, before concentration by gravitational separation equipment. Cassiterite recovery is rarely above 60 per cent, with concentrates of grade 40 to 60 per cent Sn. Fine cassiterite is recovered by flotation. Typical Australian tin mines are: The Renison mine produced 692 000 tonnes of underground ore in the 1996-97 year, of head grade 1.71 per cent tin, and produced tin concentrate (grade 53.5 per cent tin) containing 8637 tonnes of tin, for a recovery of 72.9 per cent. The Greenbushes open pit mines a deeply weathered pegmatite ore, of reserve grade 0.15 per cent Sn as cassiterite and 0.06 per cent Ta2O5 in tantalite. Tin recovery in 1997 averaged 70-75 per cent. Tin smelting is largely in reverberatory furnaces, by direct reduction, using anthracite or petroleum coke as fuel, and minor quantities of limestone as flux. There are no independent tin smelters currently operating (1999) in Australia, and most Australian concentrates are sold to smelters operated by Malaysia Smelting Corporation or Datuk Keramat Smelting, in Malaysia. Refined tin is traded on the London Metal Exchange and the Kuala Lumpur Commodities Exchange. Penalties are payable for impurities in cassiterite concentrates, of which Fe, S, Sb, Pb and Bi are the most important, with lesser emphasis on Cu, Zn, W, As, Co and Ni. The Fe limitation is dependent on Sn grade, generally accepting high Fe with low Sn content, eg four per cent Fe maximum with 75 per cent Sn, up to 15 per cent Fe with 40 per cent Sn.

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The particle size of concentrates is less critical, but a particle diameter of less than 5 mm is preferred to facilitate sampling. Purchase is generally based on a preferred minimum concentrate grade of 70 per cent Sn, with a deduction of the assay paid for of 0.1 per cent Sn for each one per cent Sn less than 70 per cent, plus a standard deduction of 1.5 per cent. These are the ‘unitage’ charges. Thus a concentrate of grade 65 per cent Sn would be paid for at 63 per cent Sn, calculated as 65 - 1.5 - (5 × 0.1). The smelting charge is in the range $500 to $1000 per tonne of concentrates. This cost is negotiated on the quantity and regularity of concentrate shipments, but most importantly on the grade and the nature and level of impurities. Major tin miners generally sell their concentrates under toll smelting contracts with the larger world smelters. The Kuala Lumpur Exchange or LME price, as quoted daily and converted to Australian currency, is used as a basis for payment.

TITANIUM AND ZIRCONIUM The principal titanium minerals are rutile (TiO2) and ilmenite (FeTiO3, nominally 53 per cent TiO2). Various alteration products of ilmenite, largely leucoxene, brookite and anatase, with TiO2 content from 50 to 92 per cent are saleable if a concentrate of uniform mineralogy and composition can be obtained in significant quantities. Titaniferous iron ores are used to make titaniferous slag in Canada, South Africa and Norway. More than 90 per cent of the titanium material produced is used to make titanium white pigment. The most important zirconium mineral is zircon (ZrSiO4, with 67.2 per cent ZrO2), often associated with rutile and ilmenite in alluvial deposits. Baddeleyite (ZrO2) is produced from primary deposits at Phalaborwa in South Africa and the Kolar peninsula in Russia. Zircon from eastern Australian deposits is colourless, contains less iron oxide and titanium impurities, and is classed as premium grade. World production in 1998 was about 476 000 tonnes of rutile, 3.9 million tonnes of ilmenite, 2.3 million tonnes of titanium slag and 800 000 tonnes of zircon. Australia is the largest producer of rutile, ilmenite and zircon. Australian operations are all based on beach and dune sand deposits, with mines on the east coast, and north and south of Perth in Western Australia Mining is by dredges (of throughput commonly 1500-3000 m3 per hour) or bulk earthmoving equipment, feeding a primary ‘wet plant’ nearby, which is fundamentally an assemblage of spiral or cone concentrators. Output at about 90 per cent heavy minerals is usually trucked to the ‘dry plant’, and the mine site rehabilitated. The dry plant contains a further concentration stage, comprising drying, a magnetic separation to remove ilmenite, and a separation of rutile and zircon in electrostatic separators and tabling to concentrate zircon.

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Minimum ore grade for the major Australian east coast sand mining industry is about 0.4 per cent (rutile + zircon); these operations have the advantage of largely established infrastructure. The major east coast producer is Consolidated Rutile Ltd, with production from its North Stradbroke Island dredges of 47 million tonnes of sand in 1997-98. Yield was 154 914 tonnes of ilmenite, 84 153 tonnes of rutile and 62 034 tonnes of zircon, for an average recovered grade of 0.65 per cent heavy minerals. The ore grade for west coast deposits is commonly about four per cent total heavy minerals, and the major mines are operated by Cable Sands (WA) Pty Ltd, the Tiwest joint venture, and Iluka Resources Ltd. Evaluation of heavy-mineral sand deposits is by grid drilling, using auger bits to the water table and bailing inside casing below this level. Reverse circulation drilling is replacing auger and bailer drilling for major programs. Drillhole data recorded include degree of induration or lateritisation, the water table level, and description of the basement. Samples are generally screened, reporting per cent oversize and undersize, then separated in a heavy liquid, determining per cent heavy minerals. The heavy mineral fraction is examined under a microscope, to determine per cent of individual minerals and the quality (coatings, inclusions, alteration) of individual mineral species. The WIM 150 deposit, near Horsham in Victoria, has at least 1000 million tonnes of sand containing an average of more than three per cent heavy minerals including zircon, rutile, anatase, leucoxene, ilmenite, monazite and xenotime. The fine-grained heavy mineral deposits at WIM150 are not currently commercially viable. Coarser-grained heavy mineral deposits in the west of the Murray Basin show considerable promise, as these can be concentrated using existing mining and concentration methods. The Wemen deposit is a classic beach or strand line type, in the Pliocene Loxton-Parilla Sands, about 25 kilometres southwest of Robinvale, Victoria. The deposit has a strike length of 11 kilometres, a maximum ore width of 300 metres and a thickness of four to 15 metres. The Measured Resource is 9.16 million tonnes of sand at five per cent heavy minerals, which contain 28 per cent rutile, 12 per cent zircon and 44 per cent ilmenite. Production should begin in 1999, with a planned mine life of ten years. The similarly coarse-grained Woomack, Rownack and Kulwin deposits, 20-25 kilometres east of the Victorian township of Ouyen, are held by RGC Exploration. Indicated Resources are 40.5 million tonnes at 9.3 per cent heavy minerals for the combined Woomack plus Rownack deposits, and 24.0 million tonnes at 11.5 per cent heavy minerals for Kulwin. Rutile is used to make white titanium dioxide pigment (by the chloride route), and to a lesser degree titanium metal and welding rod coatings. Ilmenite is almost entirely used in the manufacture of white titanium dioxide pigment (by the sulphate route), which produces large volumes of iron sulphate as a pollutant

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byproduct. The disposal of this unwanted material is invariably a problem. Several methods of upgrading ilmenite are available: 1.

The Becher or Western Titanium process, comprising the reduction of ilmenite to iron and titania by roasting, then removing most of the iron by aeration and acid leaching. The Benelite process is similar to this, with the iron removed in an acid leach only.

2.

The Murphyores method, which entails oxidation and reduction to form a ‘synthetic ilmenite’ that can be leached with HCl to remove the iron. Currently (1999) there are no commercial operations using this process.

3.

Chlorination processes, with chlorination of iron and titania.

selective

All of these produce ‘synthetic rutile’, with 90 to 94 per cent TiO2, which is broadly acceptable to titanium pigment manufacturers using the chloride route. There remains a preference for natural rutile for this route, which thus remains at a premium, but the cheaper synthetic material provides a floor for natural rutile prices. Ilmenite is smelted in South Africa, Canada and Norway to obtain pig iron and a high titania slag containing 85-90 per cent TiO2. Ilmenite sales require a minimum of 52 per cent TiO2, and very low chromium; most WA ilmenite contains less than 0.03 per cent Cr2O3. Leucoxene should have a minimum of 87 per cent TiO2, and maximum of one per cent ZrO2. East coast rutile concentrates are invariably > 95 per cent TiO2, 0.35 to 1.3 per cent ZrO2, and usually less than 0.1 per cent S (rarely to 0.2 per cent S). Zircon concentrate from the east coast is usually > 99 per cent zircon, with an average analysis > 66.5 per cent ZrO2, and less than 0.1 per cent TiO2, 0.03 per cent Fe2O3 and 0.5 per cent free silica. Zircon sand with 66 to 67 per cent ZrO2, less than 0.1 per cent TiO, and less than 0.06 per cent Fe2O3, is premium quality, known as ceramic grade. Material of lower purity, with a maximum of 0.25 per cent TiO2 and 0.15 per cent Fe2O3, and low alumina content is sold as refractory grade, and foundry grade can contain higher impurity levels.

TUNGSTEN World mine production of tungsten in 1998 was about 33 500 tonnes, dominated by production from China and Russia. The principal ore minerals are scheelite (CaWO4, with 70-80 per cent WO3) and wolframite or ‘wolfram’ (Fe,Mn)WO4, with about 76 per cent WO), which is an isomorphous series with end members ferberite (FeWO4) and huebnerite (MnWO4). The only significant Australian producer is the Kara open pit, near Burnie (Tas), which milled 103 120

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tonnes of ore in 1997 to produce 41 tonnes of scheelite and 23 300 tonnes of saleable magnetite concentrate. The King Island scheelite mine closed in 1990. Scheelite ores are concentrated after grinding to 25 mesh, with the coarse fraction treated by tabling and the fines by flotation. Primary concentrates are then roasted and treated with hydrochloric acid to remove calcite and apatite. A final flotation stage removes sulphides. In alluvial deposits, cassiterite and wolfram in jig and table concentrates may be magnetically separated to yield saleable products. Ideal specifications for readily saleable wolfram or scheelite concentrates are shown in Table 19. TABLE 19 Ideal specifications for tungsten concentrates. Component,

Wolfram conc

Scheelite conc

WO3 Sn As Mo

65.0 min. 0.5 max 0.2 max 0.05 max

S CaO Fe Mn P

1.0 max 0.5 max Up to 18 in ferberite Up to 18 in huebnerite 0.05 max

70.0 (65.0 min.) 0.2 max 0.2 max High - up to 5.0 Low - up to 3.0 1.0 18

%

0.05 max

Note: Sale prices are quoted per long ton unit or per tonne unit.

URANIUM World production in 1998 was estimated to be 89.4 million pounds of U3O8, equivalent to 40 550 tonnes of U3O8 or 34 390 tonnes of uranium. The five largest producers were Canada, Australia, Niger, Namibia and the US. The major primary ore mineral is uraninite or pitchblende (UO2 + UO3, nominally U3O8). A wide range of other uranium minerals is the major source in specific deposits. The most important of these are coffinite (hydrated uranium silicates), carnotite (uranium potassium vanadate), the daviditebrannerite-absite type (uranium titanates), and the euxenite-fergusonite-samarskite group (niobates of uranium and rare earths). A large variety of secondary uranium minerals is known; many are brilliantly coloured and fluorescent. The commonest are gummite (a general term like limonite for mixtures of secondary hydrated uranium oxides, with various impurities); hydrated uranium phosphates of the phosphuranylite type, including autunite (with calcium), saleeite (magnesian) and torbernite (with copper). A list of further radioactive minerals is provided in Carmichael (1982, pp 180-191).

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TABLE 20 Yellow cake sales specifications established by conversion plants1. Component, %

Conversion plant British Nuclear Fuel (UK)

Comurhex (France)

U

40

60

Moisture

10

5

Insol. in HNO3

Eldorado (Canada)

Allied Chemical (USA)

Kerr McGee (USA)

50

75

60

5.0

2.0

0.1

0.1

6.68

6

6.25

Mo

<0.6

0.45

V2O5

<1.0

Grain size (mm)

6.25

0.15*

0.1

0.15*

1.80

V = 0.1

0.1*

0.1*

1.15

1.0

0.05

1.0

Th

2.0

Ca

2.0

P2O5

<6

1.1

P = 0.35

PO4 = 0.1*

P = 0.35

Cl, Br, I

<0.05

0.25

0.25

0.25*

0.05

F

0.15

0.15*

0.01

0.15

SO4

10.5

S = 3.5

S = 3.0

S = 3.5

1.0

1.0

Fe

0.15

As

<2.0

CO3

<2.0

2.0

2.0

0.2

2.0

B

<0.2

0.15

0.15

0.005

0.15

Na SiO2

0.05

1.0

0.5*

K

0.1 <4.0

Zr * Indicates a penalty is payable for higher values.

All uranium minerals, when in equilibrium (which takes roughly one million years) are predictably radioactive, with the gross level of radioactivity in rock an indication of uranium content. Australian U3O8 output for 1998 was 5790 tonnes from the Ranger mine (ERA Ltd), and 1740 tonnes from Olympic Dam (WMC). ERA was preparing the Jabiluka deposit for production in 1999, as feed for the Ranger plant, and WMC was expanding its Olympic Dam operation. Throughput is to be increased to 8.5 million tonnes of ore per year, which will raise its output to 4350 tonnes of U3O8 per year. Other deposits available for development, subject to government approval, include Koongarra (NT), Yeelirrie, Manyingee and Kintyre (WA), and Valhalla and Ben Lomond (Qld). Trial insitu extraction of the Beverley and Honeymoon Well sandstone-type deposits, in the northeast of SA, began in 1998. The trials involve leaching of the ore by solutions pumped down boreholes, and pumped to the surface through production wells. The pregnant liquor is treated at the surface by conventional ion exchange or solvent extraction processes. Conventional mining, whether underground or open pit, is different from the mining of other ores only in

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0.1* 6.25

2.0

that radioactivity must be carefully monitored to avoid health hazards. Some uranium minerals are readily soluble in rainwater, and ore stockpiles should be covered to minimise uranium loss. Uranium ores are crushed and milled, and the uranium is then taken into solution, usually with sulphuric acid, or with a sodium carbonate leach for ores containing significant carbonate. After the liquid (containing uranium in solution) and the waste solids are separated, the pregnant liquor is stripped of uranium by ion exchange or solvent extraction. Uranium oxide is precipitated from the liquor with magnesia, and the uranium concentrate removed by filters as yellow cake. The yellow cake is then calcined by heating at around >700°C in a furnace, which produces a dark green powder of composition 2UO3.UO2 (written U3O8). Standards for yellow cake concentrates are shown in Table 20. The export of Australian uranium is subject to Commonwealth Government approval. 1.

From Floter, W, 1987. Development status of projects for uranium production, in Proceedings of a Technical Committee Meeting on Development of Projects for the Production of Uranium Concentrates (IAEA: Vienna).

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VANADIUM Total world consumption of vanadium as contained metal was about 148.7 million pounds (67 600 tonnes) in 1997, largely used as ferrovanadium in alloy steels. About 43 per cent of the 1997 world production was from titaniferous iron ores in the Bushveld Complex of Transvaal (Highveld Steel and Vanadium, Vantech, Rhoex and Stratcor). A further 19 per cent was produced in the Ural Mountains in the Russia, in slags from steel smelting. Further byproduct vanadium is won by refining of Caribbean crude oils. Vanadium Australia Ltd began development of the Windimurra deposit, near Mount Magnet, WA, in 1998. The deposit has a Measured and Indicated Resource of 106 million tonnes at 0.47 per cent V2O5, and the planned annual production rate is 2.28 million tonnes of ore to yield 16 million pounds of V2O5. The vanadium occurs in magnetite and ilmenite, in a magmatic deposit. Viability of the project has been enhanced by recent developments, including advances in processing technology and the availability of gas from the Dampier-Bunbury pipeline. The only historic Australian producer was the Coates mine 3 km from Wundowie, about 60 kilometres east of Perth, now inoperative. Large vanadium resources are available at Coates, at the Barrambie deposit, and near Sandstone, all in WA, and in the Julia Creek district of Qld. Up to 1000 tonnes of byproduct vanadium pentoxide per year would be available if the Yeelirrie uranium deposit is developed. Sales are on the basis of per pound V2O5 content, with both slag with minimum 25 per cent V2O5 and purified pentoxide, with minimum 98 per cent V2O5 being quoted.

REFERENCES Armstrong, M, 1998. 1998 New South Wales Coal Industry Profile (Dept of Mineral Resources: Sydney). Bates, R L and Jackson, J A (Eds), 1980. Glossary of Geology, 2nd edition (American Geological Institute: Falls Church, Virginia). Butt, B C, 1971. The exploration for and economic appraisal of asbestos, in The AusIMM 1971 Annual Conference– Preprints of Technical Papers, Vol 3, paper 36:1-19, (The Australasian Institute of Mining and Metallurgy: Melbourne). Carlson, J A, Kirkley, M B, Thomas and E M, Hillier, W D, 1999. Recent Canadian kimberlite discoveries, in Proceedings VII Kimberlite Conference (Eds: J J Gurney, J L Gurney, M D Pascoe, and S H Richardson). Carmichael, R S, 1982. Handbook of Physical Properties of Rocks, Vol 1 (CRC Press: Boca Raton). Carr, D D (Ed), 1994. Industrial Minerals and Rocks, 6th edition (Society of Mining, Metallurgy and Exploration: Littleton, Colorado). Crowson, P, 1996. Minerals Handbook 1996-97 (Macmillan Press: London).

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DME, 1998. 47th Queensland Coal Industry Review 1997-98 (Department of Mines and Energy: Brisbane). Goldie, R and Tredger, P,1993. Net smelter return models and their use in the exploration, evaluation and exploitation of polymetallic deposits, in Ore Deposit Models, Vol II (Eds: P A Sheahan and M E Cherry), pp 63-75 (Geological Association of Canada: St Johns, Newfoundland). Griffin W L (Ed), 1995. Diamond Exploration into the 21st Century, Journal of Geochemical Exploration, Vol. 53, Nos.1-3, March 1995. Griffith, J B (Ed), 1996. Industrial Minerals Prices and Data 1996, Metal Bulletin, London. Gschneidner, X A Jr and Eyring, L (Eds), 1978. Handbook on the Physics and Chemistry of Rare Earths, Vol 1 (North-Holland Publishing: Amsterdam). Harben, P W and Bates, R L, 1990. Industrial Minerals Geology and World Deposits, Metal Bulletin, London. Henderson, P (Ed), 1983. Rare Earth Element Geochemistry, Vol 2, in Developments in Geochemistry (Elsevier: Amsterdam). Jennings, C M H, Smithson, N K, 1999. The Exploration context for diamonds, Jour. Geophys. Oct. 1999, Vol. XX No.4. Jones, A P, Wall, F and Williams, C T (Eds), 1995. Rare Earth Minerals: Chemistry, Origin and Ore Deposits (Chapman and Hall: London). Jones, T (Ed), 1998. Coal 1998 (Australian Coal Report and Barlow Jonker Pty Ltd: Sydney). Lewis, P J, 1993. Revenue calculations and marketing, in Cost Estimation Handbook for the Australian Mining Industry (Eds: M Noakes and T Lanz), pp 325-368 (The Australasian Institute of Mining and Metallurgy: Melbourne). Little, H W, Belyea, H R, Scott, D F, Latour, B A and Douglas, R J W, 1970. Economic Minerals of Western Canada, in Geology and Economic Minerals of Canada (Ed: R W Douglas), pp 519-520 (Department of Energy, Mines and Resources: Ottawa). McCarthy, G J and Rhyne, J J (Eds), 1978. The Rare Earths in Modern Science and Technology (Plenum Press: New York). McLeod, I R, 1965. Australian Mineral Industry: The Mineral Deposits, BMR Bulletin 72. Marcus, J, 1997. Rio Tinto Borax and US Borax Inc, pp 24-30, Engineering and Mining Journal, October. Nixon, J C (Ed), 1987. Aluminium extraction, The AusIMM Bulletin, 292 (4):85-89. Rombouts, L, 2001. Diamonds – industry review, Mining Journal, London, August 17 2001, pp 113-115. Woodcock, J T (Ed), 1980. Mining and Metallurgical Practices in Australia, Monograph 10 (The Australasian Institute of Mining and Metallurgy: Melbourne). Woodcock, J T and Hamilton, J K (Eds), 1993. Australasian Mining and Metallurgy, Monograph 19 (The Australasian Institute of Mining and Metallurgy: Melbourne). Xu Guangxian and Xiao Jimei (Eds), 1985. New Frontiers in Rare Earth Science and Applications, Vol 1, in Proceedings International Conference in Rare Earth Development and Applications, Beijing, 1985 (Science Press: Beijing).

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4.4.1. GENERAL PREFERRED SAMPLE MASS NOMOGRAM

1

Maximum ore mineral particle diameter in mm

1.

122

From Gy, P, 1956 Nomogramme d’Echantillonnage. (Societe de Minerais et Metaux: Paris), by permission.

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4.4.2. GRAPHS OF PARTICLE SIZE AND PREFERRED SAMPLE MASS FOR 1 GOLD ASSAYS

Relationship between number of particles per 1 kg sample, particle mass (assuming all particles to be of uniform mass), and grade or tenor of the sample in parts per million. Scales to right relate grain size of gold spheres and flakes to particle mass.

1.

From Clifton, H E, Hunter, R E, Swanson, F J, and Phillips, R L, 1969. Sample size and meaningful gold analysis, USGS Prof. Paper 625-C, by permission.

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Size of sample required to contain an expected 20 particles of gold as a function of the combination of gold particle size and grade, assuming all gold particles to be of uniform size and randomly distributed in the deposit.

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4.5. AUSTRALASIAN CODE FOR REPORTING OF MINERAL RESOURCES 1 AND ORE RESERVES (THE JORC CODE) FOREWORD 1.

2.

The Australasian Code for Reporting of Mineral Resources and Ore Reserves (the ‘JORC Code’or ‘the Code’) sets out minimum standards, recommendations and guidelines for Public Reporting of exploration results, Mineral Resources and Ore Reserves in Australasia. It has been drawn up by the Joint Ore Reserves Committee of The Australasian Institute of Mining and Metallurgy, the Australian Institute of Geoscientists and the Minerals Council of Australia. The Joint Ore Reserves Committee was established in 1971 and published a number of reports which made recommendations on the classification and Public Reporting of Ore Reserves prior to the first release of the JORC Code in 1989. In this edition of the JORC Code, the guidelines, which were previously separated from the Code, have been placed after the respective Code clauses to provide improved assistance and guidance to readers. These guidelines are indented and are in a different, smaller type face. They do not form part of the Code but should be considered persuasive when interpreting the Code. The same indented and reduced type face formatting has been applied to Appendix 1 – ‘The JORC Code and Australasian Stock Exchanges’, and to Table 1 – ‘Check List of Assessment and Reporting Criteria’ to emphasise that both these sections are guidelines, and that the latter is not a mandatory list of assessment and reporting criteria. Also in this edition of the Code, the first or a particularly significant mention, after Clause 2, of terms which are defined in the Code have been marked with a superscript ‘D10’, and the corresponding definitions have been highlighted in bold type. For example, Competent PersonD10 means that this term is defined in Clause 10.

3.

The Code has been adopted by The Australasian Institute of Mining and Metallurgy and the Australian Institute of Geoscientists and is therefore binding on members of those organisations. It is supported by the Minerals Council of Australia and the Securities Institute of Australia as a contribution to best practice. The

1.

Prepared by the Joint Ore Reserves Committee of The Australasian Institute of Mining and Metallurgy, Australian Institute of Geoscientists and Minerals Council of Australia (JORC), September 1999. Note: Code is in normal typeface, guidelines are in indented italics, definitions are in bold.

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Australian Stock Exchange and New Zealand Stock Exchange listing rules each incorporate the Code. See Appendix 1. 4.

The main principles governing the operation and application of the JORC Code are transparency, materiality and competence. ‘Transparency’ requires that the reader of a Public ReportD5 is provided with sufficient information, the presentation of which is clear and unambiguous, to understand the report and is not misled. ‘Materiality’ requires that a Public Report contains all the relevant information which investors and their professional advisers would reasonably require, and reasonably expect to find in the report, for the purpose of making a reasoned and balanced judgement regarding the mineralisation being reported. ‘Competence’ requires that the Public Report is based on work which is the responsibility of a suitably qualified and experienced person who is subject to an enforceable professional code of ethics.

5.

The Code is a required minimum standard for Public Reporting. The committee also recommends its adoption as a minimum standard for other reporting. Reference in the Code to a Public Report or Public Reporting is to a report or reporting on exploration results, Mineral Resources D20 or Ore Reserves D29 , prepared for the purpose of informing investors or potential investors and their advisers. This includes a report or reporting prepared to satisfy regulatory requirements. Companies are encouraged to provide information which is as comprehensive as possible in their Public Reports. Public Reports include, but are not limited to: company Annual Reports, quarterly reports and other reports to the Australian or New Zealand Stock Exchanges or required by corporations law. It is recommended that the Code apply to the following reports if they have been prepared for the purpose described in Clause 5: environmental statements; Information Memoranda; Expert Reports and technical papers in respect of reporting on exploration results, Mineral Resources or Ore Reserves. The term ‘regulatory requirements’ as used in Clause 5 is not intended to cover reports by companies to government agencies which may be required for State Government or Federal Government inventory or planning purposes. If reports prepared for such purposes subsequently become available to the public,

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documentation prepared PersonD10 or Persons.

they would not normally be regarded as Public Reports in terms of the JORC Code (refer also to the guidelines to Clauses 20 and 37). It is recognised that there may be situations where a Competent PersonD10 prepares documentation for internal company purposes or similar non-public purposes that does not comply with the JORC Code. In such circumstances, the documentation should include a statement that it does not comply with the JORC Code. This will minimise the likelihood of non-complying documentation being used as a basis for Public Reports, since Clause 8 requires Public Reports to fairly reflect Mineral Resource and/or Ore Reserve estimates and supporting documentation prepared by a Competent Person (refer to Clause 8, and also to Appendix 1 in respect of stock exchange requirements on Public Reporting). While every effort has been made within the Code and Guidelines to cover most situations likely to be encountered in the Public Reporting of exploration results, Mineral Resources and Ore Reserves, there will inevitably be occasions when doubt exists as to the appropriate procedure to follow. In such cases, users of the Code and those compiling reports under the Code should be guided by its intent, which is to provide a minimum standard for Public Reporting and to ensure that such reporting contains all information which investors and their professional advisers would reasonably require, and reasonably expect to find in the report, for the purpose of making a reasoned and balanced judgement regarding the mineralisation being reported. 6.

The Code is applicable to all solid minerals, including diamonds, other gemstones and coal, for which Public Reporting of exploration results, Mineral Resources and Ore Reserves is required by the Australian and New Zealand Stock Exchanges.

7.

The Joint Committee recognises that further review of the Code will be required from time to time.

COMPETENCE AND RESPONSIBILITY 8.

126

A Public Report concerning a company’s Mineral Resources and/or Ore Reserves is the responsibility of the company acting through its Board of Directors. Any such report must be based on, and fairly reflect, the Mineral Resource and/or Ore Reserve estimates and supporting

by

a

Competent

In compiling Mineral Resource and/or Ore Reserve information in a Public Report, a company may need to edit the documentation prepared by the Competent Persons. Where such editing takes place, the Competent Persons must give their consent in writing to the company to the inclusion in the Public Report of the matters based on their information in the form and context in which it appears in the Public Report. Refer to Appendix 1 for information on stock exchange requirements to name the Competent Person(s). 9.

Documentation detailing Mineral Resource and Ore Reserve estimates from which a Public Report on Mineral Resources and Ore Reserves is prepared, must be prepared by or under the direction of, and signed by, a Competent Person or Persons.

10. A ‘Competent Person’ is a person who is a Member or Fellow of The Australasian Institute of Mining and Metallurgy and/or the Australian Institute of Geoscientists with a minimum of five years experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which that person is undertaking. If the Competent Person is estimating, or supervising the estimation of Mineral Resources, the relevant experience must be in the estimation, assessment and evaluation of Mineral Resources. If the Competent Person is estimating, or supervising the estimation of Ore Reserves, the relevant experience must be in the estimation, assessment, evaluation and economic extraction of Ore Reserves. The key qualifier in the definition of a Competent Person is the word ‘relevant’. Determination of what constitutes relevant experience can be a difficult area and common sense has to be exercised. For example, in estimating Mineral Resources for vein gold mineralisation, experience in a high-nugget, vein-type mineralisation such as tin, uranium etc. will probably be relevant whereas experience in (say) massive base metal deposits may not be. As a second example, for a person to qualify as a Competent Person in the estimation of Ore Reserves for alluvial gold deposits, he or she would need to have considerable (probably at least five years) experience in the evaluation and economic extraction of this type of mineralisation, due to the characteristics of gold in alluvial systems, the particle sizing of the host sediment, and the low grades

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involved. Experience with placer deposits containing minerals other than gold may not necessarily provide appropriate relevant experience. The key word ‘relevant’ also means that it is not always necessary for a person to have five years experience in each and every type of deposit in order to act as a Competent Person if that person has relevant experience in other deposit types. For example, a person with (say) 20 years experience in Mineral Resource estimation in a variety of metalliferous hard-rock deposit types may not require five years specific experience in (say) porphyry copper deposits in order to act as a Competent Person. Relevant experience in the other deposit types could count towards the required experience in relation to porphyry copper deposits. In addition to experience in the style of mineralisation, a Competent Person preparing or taking responsibility for Mineral Resource estimates should have sufficient experience in the sampling and assaying techniques relevant to the deposit under consideration to be aware of problems which could affect the reliability of the data. Some appreciation of extraction and processing techniques applicable to that deposit type would also be important. As a general guide, persons being called upon to act as Competent Persons should be clearly satisfied in their own minds that they could face their peers and demonstrate competence in the commodity, type of deposit and situation under consideration. If doubt exists, the person should either seek opinions from other colleagues or should decline to act as a Competent Person. Estimation of Mineral Resources is often a team effort (for example, involving one person or team collecting the data and another person or team preparing the Mineral Resource estimate). Within this team, geologists usually occupy the pivotal role. Estimation of Ore Reserves is almost always a team effort involving a number of technical disciplines, and within this team, mining engineers usually occupy the pivotal role. Documentation for a Mineral Resource or Ore Reserve estimate must be compiled by, or under the supervision of, a Competent Person or Persons, whether a geologist, mining engineer or member of another discipline. However, it is recommended that, where there is a clear division of responsibilities within a team, each Competent Person should accept responsibility for his or her particular

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contribution. For example, one Competent Person could accept responsibility for the collection of Mineral Resource data, another for the Mineral Resource estimation process, another for the mining study, and the project leader could accept responsibility for the overall document. It is important that the Competent Person accepting overall responsibility for a Mineral Resource or Ore Reserve estimate and supporting documentation which has been prepared in whole or in part by others is satisfied that the work of the other contributors is acceptable. If the Competent Person is a Member or Fellow of The Australasian Institute of Mining and Metallurgy (‘The AusIMM’), he or she is answerable to The AusIMM Ethics Committee if a complaint is made in respect of his or her professional work. If the Competent Person is a Member or Fellow of the Australian Institute of Geoscientists (‘AIG’), the matter will be dealt with by the Ethics and Standards Committee of the AIG Council, if a complaint is made in respect of his or her professional work. When an Australian listed or New Zealand listed company with overseas interests wishes to report an overseas Mineral Resource or Ore Reserve estimate prepared by a person who is not a member of The AusIMM or of the AIG, it is necessary for the company to nominate a Competent Person or Persons to take responsibility for the Mineral Resource or Ore Reserve estimate. The Competent Person or Persons undertaking this activity should appreciate that they are accepting full responsibility for the estimate and supporting documentation under ASX or NZSX listing rules and should not treat the procedure merely as a ‘rubber-stamping’ exercise. 11. For Public Reports dealing with diamond or other gemstone mineralisation, it is also a requirement of this Code that, if a valuation of a parcel of diamonds or gemstones is reported, the person(s) or organisations valuing the parcel must be named in the report and their professional valuation experience, competency and independence stated.

REPORTING TERMINOLOGY 12. Public Reports dealing with Mineral Resources and/or Ore Reserves must only use the terms set out in Figure 1. Figure 1 sets out the framework for classifying tonnage and grade estimates so as to reflect different levels of geological confidence and different degrees of technical and economic evaluation. Mineral Resources

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can be estimated mainly by a geologist on the basis of geoscientific information with some input from other disciplines. Ore Reserves, which are a modified sub-set of the IndicatedD22 and Measured Mineral ResourcesD23 (shown within the dashed outline in Figure 1), require consideration of those factors affecting extraction, including mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors, and should in most instances be estimated with input from a range of disciplines. In certain situations,

Measured Mineral Resources could convert to Probable Ore Reserves D30 because of uncertainties associated with the modifying factors which are taken into account in the conversion from Mineral Resources to Ore Reserves. This relationship is shown by the broken arrow in Figure 1 (although the trend of the broken arrow includes a vertical component, it does not, in this instance, imply a reduction in the level of geological knowledge or confidence). In such a situation these modifying factors should be fully explained. Refer also to the guidelines to Clause 32.

FIG 1 - General Relationship between Exploration Results, Mineral Resources and Ore Reserves.

REPORTING – GENERAL 13. Public Reports concerning a company’s Mineral Resources or Ore Reserves should include a description of the style and nature of mineralisation. 14. A company must disclose relevant information concerning the status and characteristics of a mineral deposit which could materially influence the economic value of that deposit. A company must promptly report any material changes in its Mineral Resources or Ore Reserves. 15. Companies must review and publicly report on Mineral Resources and Ore Reserves annually. 16. Throughout the Code, where appropriate, ‘quality’ may be substituted for ‘grade’ and ‘volume’ may substituted for ‘tonnage’.

REPORTING OF EXPLORATION RESULTS 17. A company may choose, or be required under stock exchange listing rules, to report exploration

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results. If a company reports exploration results in relation to mineralisation not classified as a Mineral Resource or an Ore Reserve, then estimates of tonnage and average grade must not be assigned to the mineralisation. Where descriptions of exploration targets or exploration potential are given in Public Reports, any tonnage/grade figures mentioned must be clearly order-of-magnitude and conceptual in nature and expressed so as not to misrepresent them as an estimate of Mineral Resources or Ore Reserves. 18. Public Reports of exploration results relating to mineralisation not classified as Mineral Resources or Ore Reserves must contain sufficient information to allow a considered and balanced judgement of the significance of the results. This must include relevant information such as sampling intervals and methods, sample locations, assay data, laboratory analyses, data aggregation methods plus information on any of the other criteria listed in Table 1 that are material to an

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assessment. The reporting of exploration sampling or geophysical results must not be presented so as to unreasonably imply that potentially economic mineralisation has been discovered. Table 1 is a check list and guideline to which those preparing reports on exploration results, Mineral Resources and Ore Reserves should refer. The check list is not prescriptive and, as always, relevance and materiality are overriding principles which determine what information should be publicly reported. Reporting of isolated assays without placing them in perspective is unacceptable. 19. Public Reports dealing with diamonds require the following additions:

• Reports of diamonds recovered from sampling programs must specify the number and total weight (in carats) of diamonds recovered. Details of the type and size of samples which produced the diamonds must also be specified including the lower cut-off sieve size used in the recovery.

• The weight of diamonds recovered may only be omitted from the report when the diamonds are less than 0.4 mm in size (ie when the diamonds recovered are microdiamonds).

REPORTING OF MINERAL RESOURCES 20. A ‘Mineral Resource’ is a concentration or occurrence of material of intrinsic economic interest in or on the Earth’s crust in such form and quantity that there are reasonable prospects or eventual economic extraction. The location, quantity, grade, geological characteristics and continuity of a Mineral Resource are known, estimated or interpreted from specific geological evidence and knowledge. Mineral Resources are sub-divided, in order of increasing geological confidence, into InferredD21, IndicatedD22 and D23 categories. Measured Portions of a deposit that do not have reasonable prospects for eventual economic extraction must not be included in a Mineral Resource. The term ‘Mineral Resource’ covers mineralisation which has been identified and estimated through exploration and sampling and within which Ore Reserves may be defined by the consideration and application of technical, economic, legal, environmental, social and governmental factors. The term ‘reasonable prospects for eventual economic extraction’ implies a judgement (albeit preliminary) by the Competent Person in respect of the technical and economic factors likely to influence the prospect of

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economic extraction, including the approximate mining parameters. In other words, a Mineral Resource is not an inventory of all mineralisation drilled or sampled, regardless of cut-off grade, likely mining dimensions, location or continuity. It is a realistic inventory of mineralisation which, under assumed and justifiable technical and economic conditions, might, in whole or in part, become economically extractable. Interpretation of the word ‘eventual’ in this context may vary depending on the commodity or mineral involved. For example, for many coal, iron ore, bauxite and other bulk minerals or commodities, it may be reasonable to envisage ‘eventual economic extraction’ as covering time periods in excess of 50 years. However for the majority of gold deposits, application of the concept would normally be restricted to perhaps 20 to 30 years, and frequently to much shorter periods of time. Certain reports (eg: coal inventory reports, exploration reports to government and other similar reports not intended primarily for providing information for investment purposes) may require full disclosure of all mineralisation, including some material that does not have reasonable prospects for eventual economic extraction. Such estimates of mineralisation would not qualify as Mineral Resources or Ore Reserves in terms of the JORC Code (refer also to the guidelines to Clauses 5 and 37). Where considered appropriate by the Competent Person, Mineral Resource estimates may include material below the selected cut-off grade to ensure that the Mineral Resources comprise bodies of mineralisation of adequate size and continuity to properly consider the most appropriate approach to mining. Documentation of Mineral Resource estimates should clearly identify any such inclusions, and Public Reports should include commentary on the matter if considered material. 21. An ‘Inferred Mineral Resource’ is that part of a Mineral Resource for which tonnage, grade and mineral content can be estimated with a low level of confidence. It is inferred from geological evidence and assumed but not verified geological and/or grade continuity. It is based on information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes which may be limited or of uncertain quality and reliability.

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An Inferred Mineral Resource has a lower level of confidence than that applying to an Indicated Mineral Resource. The category is intended to cover situations where a mineral concentration or occurrence has been identified and limited measurements and sampling completed, but where the data are insufficient to allow the geological and/or grade continuity to be confidently interpreted. Due to the uncertainty which may attach to some Inferred Mineral Resources, it cannot be assumed that all or part of an Inferred Mineral Resource will be upgraded to an Indicated or Measured Mineral Resource as a result of continued exploration. Confidence in the estimate is usually not sufficient to allow the appropriate application of technical and economic parameters or to enable an evaluation of economic viability. Caution should be exercised if this category is considered in economic studies. 22. An ‘Indicated Mineral Resource’ is that part of a Mineral Resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a reasonable level of confidence. It is based on exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes. The locations are too widely or inappropriately spaced to confirm geological and/or grade continuity but are spaced closely enough for continuity to be assumed. An Indicated Mineral Resource has a lower level of confidence than that applying to a Measured Mineral Resource, but has a higher level of confidence than that applying to an Inferred Mineral Resource. Mineralisation may be classified as an Indicated Mineral Resource when the nature, quality, amount and distribution of data are such as to allow confident interpretation of the geological framework and to assume continuity of mineralisation. Confidence in the estimate is sufficient to allow the appropriate application of technical and economic parameters and to enable an evaluation of economic viability. 23. A ‘Measured Mineral Resource’ is that part of a Mineral Resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a high level of confidence. It is based on detailed and reliable exploration, sampling and testing information gathered through appropriate

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techniques from locations such as outcrops, trenches, pits, workings and drill holes. The locations are spaced closely enough to confirm geological and/or grade continuity. Mineralisation may be classified as a Measured Mineral Resource when the nature, quality, amount and distribution of data are such as to leave no reasonable doubt, in the opinion of the Competent Person determining the Mineral Resource, that the tonnage and grade of the mineralisation can be estimated to within close limits and that any variation from the estimate would not significantly affect potential economic viability. This category requires a high level of confidence in, and understanding of, the geology and controls of the mineral deposit. Confidence in the estimate is sufficient to allow the appropriate application of technical and economic parameters and to enable an evaluation of economic viability. 24. The choice of the appropriate category of Mineral Resource depends upon the quantity, distribution and quality of data available and the level of confidence that attaches to those data. The appropriate Mineral Resource category must be determined by a Competent Person or Persons. Mineral Resource classification is a matter for skilled judgement and Competent Persons should take into account those items in Table 1 which relate to confidence in Mineral Resource estimation. In deciding between Measured Mineral Resources and Indicated Mineral Resources, Competent Persons may find it useful to consider, in addition to the phrases in the two definitions relating to geological and grade continuity in Clauses 22 and 23, the phrase in the guideline to the definition for Measured Mineral Resources: ‘.... any variation from the estimate would not significantly affect potential economic viability’. In deciding between Indicated Mineral Resources and Inferred Mineral Resources, Competent Persons may wish to take into account, in addition to the phrases in the two definitions in Clauses 21 and 22 relating to geological and grade continuity, the guideline to the definition for Indicated Mineral Resources: ‘Confidence in the estimate is sufficient to allow the appropriate application of technical and economic parameters and to enable an evaluation of economic viability’, which contrasts with the guideline to the definition for Inferred Mineral Resources: ‘Confidence in the estimate is usually not sufficient to allow the appropriate application

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of technical and economic parameters or to enable an evaluation of economic viability. Caution should be exercised if this category is considered in economic studies’. 25. Mineral Resource estimates are not precise calculations, being dependent on the interpretation of limited information on the location, shape and continuity of the occurrence and on the available sampling results. Reporting of tonnage and grade figures should reflect the order of accuracy of the estimate by rounding off to appropriately significant figures and, in the case of Inferred Mineral Resources, by qualification with terms such as ‘approximately’. In most situations, rounding to the second significant figure should be sufficient. For example 10 863 000 tonnes at 8.23 per cent should be stated as 11 million tonnes at 8.2 per cent. There will be occasions, however, where rounding to the first significant figure may be necessary in order to convey properly the uncertainties in estimation. This would usually be the case with Inferred Mineral Resources. To emphasise the imprecise nature of a Mineral Resource or Ore Reserve estimate, the final result should always be referred to as an estimate not a calculation. 26. Public Reports of Mineral Resources must specify one or more of the categories of ‘Inferred’, ‘Indicated’ and ‘Measured’. Categories must not be reported in a combined form unless details for the individual categories are also provided. Mineral Resources must not be reported in terms of contained metal or mineral content unless corresponding tonnages and grades are also presented. Mineral Resources must not be aggregated with Ore Reserves. 27. Table 1 provides, in a summary form, a list of the main criteria which should be considered when preparing reports on exploration results, Mineral Resources and Ore Reserves. These criteria need not be discussed in a Public Report unless they materially affect estimation or classification of the Mineral Resources. Where diamond Mineral Resource grades are based on the correlation of macrodiamond grade with the grade of microdiamonds, this must be stated and its reliability explained. It is not necessary, when publicly reporting, to comment on each item in Table 1, but it is essential to discuss any matters which might materially affect the reader’s understanding or interpretation of the results or estimates being reported. This is particularly important where inadequate or uncertain data affect the

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reliability of, or confidence in, a statement of exploration results or an estimate of Mineral Resources and/or Ore Reserves; for example, poor sample recovery, poor repeatability of assay or laboratory results, limited information on tonnage factors etc. If there is doubt about what should be reported, it is better to err on the side of providing too much information rather than too little. Mineral Resource or Ore Reserve estimates are sometimes reported after adjustment by cutting of high grades, or after the application of modifying factors arising from reconciliation with mill data. If any of the data are materially adjusted or modified for the purpose of making the estimate, or if the estimate is subsequently adjusted, this should be clearly stated in a Public Report of Mineral Resources or Ore Reserves and the nature of the adjustment or modification described. 28. The words ‘ore’ and ‘reserves’ must not be used in stating Mineral Resource estimates as the terms imply technical feasibility and economic viability and are only appropriate when all relevant technical, economic, marketing, legal, environmental, social and governmental factors have been considered. Reports and statements should continue to refer to the appropriate category or categories of Mineral Resources until technical feasibility and economic viability have been established. If re-evaluation indicates that the Ore Reserves are no longer viable, the Ore Reserves must be reclassified as Mineral Resources or removed from Mineral Resource/Ore Reserve statements. It is not intended that re-classification from Ore Reserves to Mineral Resources should be applied as a result of changes expected to be of a short term or temporary nature, or where company management has made a deliberate decision to operate on a non-economic basis. Examples of such situations might be a commodity price drop expected to be of short duration, mine emergency of a non-permanent nature, transport strike etc.

REPORTING OF ORE RESERVES 29. An ‘Ore Reserve’ is the economically mineable part of a Measured or Indicated Mineral Resource. It includes diluting materials and allowances for losses which may occur when the material is mined. Appropriate assessments, which may include feasibility studies, have been carried out, and include consideration of and modification by

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realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors. These assessments demonstrate at the time of reporting that extraction could reasonably be justified. Ore Reserves are sub-divided in order of increasing confidence into Probable Ore ReservesD30 and Proved Ore ReservesD31. Ore Reserves are those portions of Mineral Resources which, after the application of all mining factors, result in an estimated tonnage and grade which, in the opinion of the Competent Person or Persons making the estimates, can be the basis of a viable project after taking account of all relevant metallurgical, economic, marketing, legal, environmental, social and governmental factors. Ore Reserves are inclusive of diluting material which will be mined in conjunction with the Ore Reserves and delivered to the treatment plant or equivalent. The term ‘economic’ implies that extraction of the Ore Reserve has been established or analytically demonstrated to be viable and justifiable under reasonable investment assumptions. The term ‘Ore Reserve’ need not necessarily signify that extraction facilities are in place or operative or that all governmental approvals have been received. It does signify that there are reasonable expectations of such approvals. It should be noted that the Code does not imply that an economic operation must have Proved Ore Reserves. Situations arise where Probable Ore Reserves alone may be sufficient to justify extraction, as for example with some alluvial tin or gold deposits. Some countries use the term ‘Mineral Reserve’ instead of ‘Ore Reserve’. The Joint Ore Reserves Committee has retained the term ‘Ore Reserve’ because it assists in maintaining a clear distinction between a ‘Mineral Resource’ and an ‘Ore Reserve’, a distinction which might be less clear if ‘Mineral Reserve’ was substituted. However, if preferred by the reporting company, ‘Ore Reserve’ and Mineral Resource’ estimates for coal may be reported as ‘Coal Reserve’ and ‘Coal Resource’ estimates. 30. A ‘Probable Ore Reserve’ is the economically mineable part of an Indicated, and in some circumstances Measured Mineral Resource. It includes diluting materials and allowances for losses which may occur when the material is mined. Appropriate assessments, which may include feasibility studies, have been carried out, and include consideration of and

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modification by realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors. These assessments demonstrate at the time of reporting that extraction could reasonably be justified. A Probable Ore Reserve has a lower level of confidence than a Proved Ore Reserve. 31. A ‘Proved Ore Reserve’ is the economically mineable part of a Measured Mineral Resource. It includes diluting materials and allowances for losses which may occur when the material is mined. Appropriate assessments, which may include feasibility studies, have been carried out, and include consideration of and modification by realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors. These assessments demonstrate at the time of reporting that extraction could reasonably be justified. 32. The choice of the appropriate category of Ore Reserve is determined primarily by the classification of the corresponding Mineral Resource and must be made by the Competent Person or Persons. The Code provides for a direct relationship between Indicated Mineral Resources and Probable Ore Reserves and between Measured Mineral Resources and Proved Ore Reserves. In other words, the level of geoscientific confidence for Probable Ore Reserves is the same as that required for the in situ determination of Indicated Mineral Resources and for Proved Ore Reserves is the same as that required for the in situ determination of Measured Mineral Resources. The 1999 edition of the Code also provides, for the first time, for a two-way relationship between Measured Mineral Resources and Probable Ore Reserves. This is to cover the situation where uncertainties associated with any of the modifying factors considered when converting Mineral Resources to Ore Reserves may result in there being a significantly lower degree of confidence in the Ore Reserves than in the corresponding Measured Mineral Resources. Such a conversion would not imply a reduction in the level of geological knowledge or confidence. If the uncertainties in the modifying factors preventing the Measured Mineral Resource being converted to a Proved Ore Reserve are removed, the Measured Mineral Resource

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may be converted to a Proved Ore Reserve. However modification is only acceptable to an equivalent or lower level of confidence. No amount of confidence in the modifying factors for conversion of a Mineral Resource to an Ore Reserve can override the upper level of confidence which exists in the Mineral Resource. Under no circumstances can an Indicated Mineral Resource be converted directly to a Proved Ore Reserve.

reporting has been adopted. Appropriate forms of clarifying statements may be:

Application of the category of a Proved Ore Reserve implies the highest degree of confidence in the estimate with consequent expectations in the minds of readers of the report. These expectations should be borne in mind when categorising a Mineral Resource as Measured.

Inferred Mineral Resources are, by definition, always additional to Ore Reserves.

Refer also to the guidelines to Clause 24 regarding classification of Mineral Resources. 33. Ore Reserve estimates are not precise calculations and tonnage and grade figures in Public Reports should be expressed so as to convey the order of accuracy of the estimates by rounding off to appropriately significant figures. Refer to the guidelines to Clause 25, regarding rounding of Mineral Resource estimates. 34. Except for the special provisions relating to coal (see Clause 39) Public Reports of Ore Reserves must specify one or both of the categories of ‘Proved’ and ‘Probable’. Categories must not be reported in a combined form unless details for the individual categories are also provided. Ore Reserves must not be reported in terms of contained metal or mineral content unless corresponding tonnages and grades are also presented. In reporting Ore Reserves, information on assumed metallurgical recovery factors is very important, and should always be included in Public Reports. 35. In situations where figures for both Mineral Resources and Ore Reserves are reported, a clarifying statement must be included in the report which clearly indicates whether the Mineral Resources are inclusive of, or additional to the Ore Reserves. The committee recognises that there are legitimate reasons, in some situations, for reporting Mineral Resources inclusive of Ore Reserves and, in other situations, for reporting Mineral Resources additional to Ore Reserves. The committee does not express a preference but it does require that reporting companies make it clear which form of

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‘The Measured and Indicated Mineral Resources are inclusive of those Mineral Resources modified to produce the Ore Reserves.’ or: ‘The Measured and Indicated Mineral Resources are additional to the Ore Reserves.’

Where there is a substantial difference between the statement of Mineral Resources and the statement of Ore Reserves in a Public Report, an explanation of the reasons for the difference should be included in the report. This will assist the reader of the report in making a judgement of the likelihood of the remaining Mineral Resources eventually being converted to Ore Reserves. Ore Reserves may incorporate material (dilution) which is not part of the original Mineral Resource. It is essential that this fundamental difference between Mineral Resources and Ore Reserves is borne in mind and caution exercised if attempting to draw conclusions from a comparison of the two. For the same reason, Ore Reserves should not be added to Mineral Resources. The resulting total can be very misleading in economic terms and is capable of being misunderstood or, more seriously, of being misused to give a false impression of a company’s mineral prospects. Public Reporting of tonnage and grade estimates using terms other than Mineral Resources and Ore Reserves is not permitted under the Code. In preparing the Ore Reserve statement, the relevant Mineral Resource statement on which it is based should first be developed. This can be reconciled with the Mineral Resource statement estimated for the previous comparable period and differences (due, for example, to mine production, exploration etc) identified. The application of cut-off and other criteria to the Mineral Resource can then be made to develop the Ore Reserve statement which can also be reconciled with the previous comparable statement. Companies are encouraged whenever possible to reconcile estimates in their reports. A detailed account of differences between estimates is not essential, but sufficient comment should be made to enable significant variances to be understood by the reader.

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36. Table 1 provides, in a summary form, a list of the main criteria which should be considered when preparing reports on exploration results, Mineral Resources and Ore Reserves. These criteria need not be discussed in a Public Report unless they materially affect estimation or classification of the Ore Reserves. Changes in economic or political factors alone may be the basis for significant changes in Ore Reserves and should be reported accordingly. Where diamond Ore Reserve grades are based on the correlation of macrodiamond grade with the grade of microdiamonds, this must be stated and its reliability explained. If a valuation of a parcel of diamonds is reported, the weight in carats and size range of the contained diamonds must be stated and the value of the diamonds must be given in US dollars per carat. Refer also to Clause 19 and to the guidelines to Clause 27.

REPORTING OF COAL RESOURCES AND RESERVES 37. Clauses 38 to 40 of the Code address matters which relate specifically to the Public Reporting of Coal Resources and Reserves. Unless otherwise stated, clauses 1 to 36 of this Code (including Figure 1) apply. Table 1, as part of the guidelines, should also be considered persuasive when reporting on Coal Resources and Reserves. For guidance on the estimation of black Coal Resources and Reserves and on statutory reporting not primarily intended for providing information to the investing public, readers are referred to the 1999 edition of the ‘Guidelines for the Estimation and Reporting of Australian Black Coal Resources and Reserves’, a document drawn up by a committee of coal industry and government representatives and consultants from New South Wales and Queensland. Coal is of particular interest to State and Federal Governments because of its impact on government planning and land use implications. Reports to governments may require estimates of coal resources which are not constrained by short to medium term economic considerations. Such reports and estimates of strategic resources are not covered by the JORC Code. Refer also to the guidelines to Clauses 5 and 20.

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38. The terms ‘Mineral Resource(s)’ and ‘Ore Reserve(s)’, and the subdivisions of these as defined above, apply also to coal reporting, but if preferred by the reporting company, the terms ‘Coal Resource(s)’ and ‘Coal Reserve(s)’ and appropriate subdivisions may be substituted. 39. For coal reporting only, Probable and Proved Ore (Coal) Reserves may be combined and reported as Recoverable Reserves. 40. Reports of ‘Marketable Coal Reserves’, representing beneficiated or otherwise enhanced coal product, may be used in Public Reports in conjunction with, but not instead of, reports of Ore (Coal) Reserves. The basis of the predicted yield to achieve MaZrketable Coal Reserves should be stated.

REPORTING OF MINERALISED STOPE FILL, STOCKPILES, REMNANTS, PILLARS, LOW GRADE MINERALISATION AND TAILINGS 41. The Code applies to the reporting of all potentially economic mineralised material including mineralised stope fill, stockpiles, remnants, pillars, low grade mineralisation and tailings. For the purposes of the Code, mineralised stope fill and stockpiles of mineralised material can be considered to be similar to in situ mineralisation when reporting Mineral Resources and Ore Reserves. Consequently the Competent Person assessing the fill or stockpiles must use the bases of classification outlined in the Code. In most cases, the opinion of a relevant professional should be sought when making judgements about the mineability of fill, remnants and pillars. If there are not reasonable prospects for the eventual economic extraction of a particular portion of the fill or stockpile, this material cannot be classified as either Mineral Resources or Ore Reserves. If some portion is currently sub-economic but there is a reasonable expectation that it will become economic, then this material may be classified as a Mineral Resource. Such stockpile material may include old dumps and tailings dam material. If technical and economic studies have demonstrated that economic extraction could reasonably be justified under realistically assumed conditions, the material may be classified as an Ore Reserve.

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The above guidelines apply equally to low grade in situ mineralisation, sometimes referred to as ‘mineralised waste’ or ‘marginal grade material’, and often intended for stockpiling and treatment towards the end of mine life. For clarity of understanding, it is recommended that tonnage and grade estimates of such material be itemised separately in Public Reports, although they may be aggregated with total Mineral Resource and Ore Reserve figures. Stockpiles are defined to include both surface and underground stockpiles, including broken ore in stopes, and can include ore currently in the ore storage system. Mineralised material being processed (including leaching), if reported, should be reported separately. Mineralised remnants, shaft pillars and mining pillars which are potentially mineable are in situ mineralisation and consequently are included in the Code definitions of Mineral Resources and Ore Reserves. Mineralised remnants, shaft pillars and mining pillars which are not potentially mineable must not be included in Mineral Resource and Ore Reserve statements.

CHECK LIST OF ASSESSMENT AND REPORTING CRITERIA Table 1 is a check list and guideline which those preparing reports on exploration results, Mineral Resources and Ore Reserves should use as a reference. The check list is not prescriptive and, as

always,

overriding

relevance principles

and that

materiality determine

are what

information should be publicly reported. It is, however, important to report any matters that might materially affect a reader’s understanding or interpretation of the results or estimates being reported. This is particularly important where inadequate or uncertain data affect the reliability of, or confidence in, a statement of exploration results or an estimate of Mineral Resources and/or Ore Reserves. The order and grouping of criteria in Table 1 reflects the normal systematic approach to exploration and evaluation. Criteria in the first group ‘Sampling Techniques and Data’ apply to all succeeding groups. In the remainder of the table, criteria listed in preceding groups would often apply to succeeding groups and should be considered when estimating and reporting.

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TABLE 1 Check list of assessment and reporting criteria.

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APPENDIX 1 THE JORC CODE AND AUSTRALASIAN STOCK EXCHANGES The Australian and New Zealand Stock Exchanges (‘ASX’ and ‘NZSX’) have, since 1989 and 1992 respectively, incorporated the Code into their listing rules. Under these listing rules, a Public Report must be prepared in accordance with the Code if it includes a statement on exploration results, Mineral Resources

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or Ore Reserves. The incorporation of the Code imposes certain specific requirements on mining or exploration companies reporting to the ASX and NZSX. The guidelines in this section of the Code which paraphrase these requirements should not be used as a replacement for the relevant listing rules, and it is strongly recommended that users of the Code familiarise themselves with those listing rules which relate to Public Reporting of exploration results, Mineral Resources and Ore Reserves.

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ASX listing rules require the Competent Person(s), on whose work the Public Report of Mineral Resources or Ore Reserves is based, to be named in the report. The report or attached statement must say that the person consents to the inclusion in the report of the matters based on their information in the form and context in which it appears, and must include the name of the person’s firm or employer. Refer also to Clause 8 of the Code. Appropriate forms of compliance statements may be as follows (delete bullet points which do not apply):

Member of The Australasian Institute of Mining and Metallurgy or the Australian Institute of Geoscientists (select as appropriate)’.

• If the Competent Person is a full-time employee of the company: ‘(Insert name of Competent Person) is a full-time employee of the company’.

• If the Competent Person is not a full-time employee of the company:

• If the required information is in the report: ‘The information in this report that relates to Mineral Resources or Ore Reserves is based on information compiled by (insert name of Competent Person), who is a Fellow or Member of The Australasian Institute of Mining and Metallurgy or the Australian Institute of Geoscientists (select as appropriate)’: or

‘(Insert name of Competent Person) is employed by (insert name of Competent Person’s employer)’.

• For all reports: ‘(Insert name of Competent Person) has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he (or she) is undertaking to qualify as a Competent Person as defined in the 1999 Edition of the ‘Australasian Code for Reporting of Mineral Resources and Ore Reserves’. (Insert name of Competent Person) consents to the inclusion in the report of the matters based on their information in the form and context in which it appears’.

• If the required information is included in an attached statement: ‘The Information in the report to which this statement is attached that relates to Mineral Resources or Ore Reserves is based on information compiled by (insert name of Competent Person), who is a Fellow or

4.6. STANDARD CLASSIFICATION SYSTEM FOR AUSTRALIAN HARD 1 COAL SCOPE This standard describes a system of classification for Australian hard coals.

METHODS OF ANALYSIS For methods of analysis, and the appropriate tolerances, reference should be made to AS K152, Methods for the Analysis and Testing of Coal and Coke, Parts 1-16, as appropriate.

DEFINITIONS For the purpose of this standard the following definitions apply: Note: The standard conditions referred to in this clause are those defined in AS K153, Part I—The 1.

From Anon, 1969. Classification System for Australian Hard Coal, Aust. Standard K 184, p 7. (Standards Assocn. Aust.: Sydney), by permission.

Sampling of Hard Coal, as appropriate. Hard coal—coal having or exceeding a gross calorific value of 6470 kcal/kg on a dry ash-free (d.a.f.) basis. Swelling number—a number which defines, by reference to a series of standard profiles, the size and shape of the residue produced when a standard weight of coal is heated under standard conditions. Gray King coke type—a letter which defines, by reference to a series of standard profiles, the size and texture of the coke residue produced when a standard weight of coal is heated in a retort tube to 600°C under standard conditions. Air-dried moisture—that part of the total mois-ture which is retained by the coal after it has been exposed to the atmosphere and has gained approximate equilibrium. Volatile matter—material other than moisture which is driven off when coal is heated under standard conditions. The basis used is dry mineral-matter-free (Est) according to the following formula: V=

140

100(v − 01 . A) 100 − 11 .A Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE 1 Coal class based on volatile matter.

where V = volatile matter (dmmf Est basis) v = volatile matter (dry basis) A = ash (dry basis) Ash—the inorganic residue after the incineration of coal to constant weight under standard conditions. Gross calorific value—the number of heat units measured as being liberated per unit quantity of fuel burned in oxygen in a bomb under standard conditions in such a way that the material after combustion (suitable corrections having been made) consists of gaseous oxygen, carbon dioxide and nitrogen, liquid water in equilibrium with its vapour and saturated with carbon dioxide, and ash.

Class number

Volatile matter (dmmf Est) per cent

1

≤ 10

2

> 10-14

3

> 14-20

4A

> 20-24

4B

> 24-28

5

> 28-33

CLASS, GROUP AND SUB-GROUP

CODE NUMBERING SYSTEM

General. The classification of hard coal is dependent upon the nature and the composition of the organic matter in the coal which in turn, determines the suitability of the coal for a given application, but additionally, all coals contain inorganic impurities which lessen their suitability for certain commercial applications. Properties used to classify coals are volatile matter (on dmmf basis) and gross calorific value (on d.a.f. basis). Properties which supply additional information are crucible swelling index and the Gray King coke type. Coal class. The coal class is determined by volatile matter, on dmmf (Est) basis, until the figure of 33 per cent is reached as shown in Table 1. If the volatile matter exceeds 33 per cent the coal class is then determined by the use of gross calorific value, on d.a.f. basis (Table 2). Using these parameters provision is made for 10 classes of coal as shown in Tables 1 and 2.

It is recommended that a hard coal be described by a code numbering system in terms of the concepts given in this standard as illustrated in the following example. A coal was reported to have the following characteristics: Volatile matter (dmmf Est)..............37% Calorific value (d.a.f.).....................15 050 Btu/lb Crucible swelling index...................6 Gray King coke type........................G5 Ash (dry basis).................................16.9 As the volatile matter on a dmmf Est basis is greater than 33 per cent, the class number is determined by the gross calorific value on a daf basis. As the gross calorific value is more than 14 540 Btu/lb the coal belongs in Class 6, which becomes the first digit of the code number. The crucible swelling index is 6; so the coal belongs in Group 3, which becomes the second digit of the code number. As the Gray King coke type

TABLE 2 Coal class based on gross calorific value. Class number

Gross calorific value d.a.f. basis kcal/kg

maf basis* Btu/lb

Volatile matter (dmmf Est)*

kcal/kg

6

> 8080

> 14540

> 7750

33-41

7

> 7650-8080

> 13770-14540

> 7200-7750

33-44

8

> 6790-7650

> 12220-13770

> 6100-7200

35-50

9

> 6470-6790

≥11650-12220

5700-6100

42-50

* Included for information only. Notes: 1.

Gross calorific value may be calculated from the following formula: CVmaf = 1.277 CVdaf – 2567 kcal/kg.

2.

1 kcal/kg = 4.1868 kJ/kg (SI units).

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141

MINING AND ECONOMIC GEOLOGY

is G5, the coal belongs in sub-group 4, which is the third digit of the code number. As the ash of the coal is 1 6.5 per cent the fourth digit is 3 and the code number of the coal would then be 634(3). Coal group. The coal classes determined in above are subdivided into groups dependent upon the crucible swelling number as shown in Table 3. TABLE 3 Coal group based on crucible swelling number. Group number

Crucible swelling number

0

0-½

1

1-2

2

2½-4

3

4½-6

4

6½-9

Sub-group. The coal groups determined in above are further subdivided into sub-groups according to the Gray King coke type as shown in Table 4. Ash. The coal is further classified by a figure which indicates the ash as shown in Table 5.

TABLE 4 Coal sub-group. Sub- Group number

Gray King coke type

0

A

1

B-D

2

E-G

3

G1-G4

4

G5-G8

5

G 9-

TABLE 5 Ash Number. Ash number

Ash (dry basis)

0

≤4

1

≤8

2

> 8-12

3

> 12-16

4

> 16-20

5

> 20-24

6

> 24-28

7

> 28-32

8

> 32-

4.7.1. SUMMARY OF COMPOUND INTEREST FORMULAE

Effective interest rate — E E is interest rate which when applied once per year to a principal sum (P) will give the same amount of interest as the nominal rate r com-pounded m times per year. i is the period interest rate. = r/m.

1.

142

1

Single payment compound amount factor — F/Pi, n F is the future worth, n years from now, of a present sum of money P with compounded interest at i% per year.

From Stermole, F J, 1974. Economic Evaluation and Investment Decision Methods (Investment Evaluations Corporation: Golden. Colo.) by permission.

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

Single payment present worth factor — P/Fi, n

(6) A = F

If F is known, the present value P can he calculated from (2) above as (3) P = F

( (1 1+ i ) )= F(P/Fi, n), where (P/Fi, n

P

1

2 - - - - - n

i(1 + i) n

A?

n

(1 + i) − 1

= P(A/Pi, n) where A/Pi, n) is the capital recovery factor.

The present sum P, equivalent to a uniform series of equal payments A for n periods at i% interest per period is:

A

P?

A

A

2 - - - - - n

1

0

n

P=A

(1 + i) − 1 i(1 + i)

The future worth F, for a series of equal annual investments A, for n years at i% compound interest per year.

n

(8) P = A(P/Ai, n) where (P/Ai, n) is the uniform series present worth factor. Arithmetic gradient series factor — A/Gi, n

A

A

1

F=? 2 - - - - - - n years

For incomes or payments which increase or decrease in an arithmetic series, in which B isthe first term in the gradient series and g is the constant gradient between terms.

F = A + A(1 + i) + - - - A (1 + i)n − 1 (1 + i)n − 1 =A i

B

(5) F = A (F/Ai, n) where (F/Ai, n) is the uniform series compound amount factor.

From equation (5) above, the amount A that must be deposited in a fund at the end of each period for n periods, at i% interest per period. to accumulate a sum F is:

A?

A?

1

2------n

0

1

B + g B + 2g B + (n − 1)g

2

3 - - - - - - n

The arithmetic series can be equated to a uniform series of equal annual payments, A, at a rate of interest i, by

Sinking fund deposit factor — A/Fi, n

Field Geologists’ Manual

A?

Uniform series present worth factor — P/Ai, n

Uniform series compound amount factor — F/Ai, n

0

= F (A/Fi, n) where (A/Fi, n) is the sinking fund deposit factor.

A? 0

(7) A = P

An

)

The uniform payment A, being a payment at the end of each period for n periods at i% interest per period, and equivalent to a known present sum P is:

Present worth equation For a series of annual cash flows, ± A0 now, ± A1 at the end of year 1, etc, then; (4) Present worth = ± A0 ± A1 (P/Fi, 1) ± A2 (P/Fi, 2)± - - ± An(P/ Fi, n) With a known series of annual cash flows, values for P/Fi, n from the tables can be used for various values of i, until a value for i is found at which present worth is zero. This particular valuc of i is the Discounted Cash Flow Rate of Return.

i

(1 + i)n − 1

Capital recovery factor — A/Pi, n

n) is the single payment present worth factor, 1 equivalent to n (1 + i)

0

(

(9) A = B ± g(A/Gi, n) where (A/Gi, n) is the arithmetic gradient series factor.

A? F

143

MINING AND ECONOMIC GEOLOGY

4.7.2. TABLE OF COMPOUND INTEREST FACTORS

1

i = 1% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.010 1.020 1.030 1.041 1.051

0.9901 0.9803 0.9706 0.9610 0.9515

1.000 2.010 3.030 4.060 5.101

1.00000 0.49751 0.33002 0.24628 0.19604

1.01000 0.50751 0.34002 0.25628 0.20604

0.990 1.970 2.941 3.902 4.853

— 0.497 0.993 1.487 1.980

6 7 8 9 10

1.062 1.072 1.083 1.094 1.105

0.9420 0.9327 0.9235 0.9143 0.9053

6.152 7.214 8.286 9.369 10.462

0.16255 0.13863 0.12069 0.10674 0.09558

0.17255 0.14863 0.13069 0.11674 0.10558

5.795 6.728 7.652 8.566 9.471

2.471 2.960 3.448 3.923 4.418

11 12 13 14 15

1.116 1.127 1.138 1.149 1.161

0.8963 0.8874 0.8787 0.8700 0.8613

11.567 12.683 13.809 14.947 16.097

0.08645 0.07885 0.07241 0.06690 0.06212

0.09645 0.08885 0.08241 0.07690 0.07212

10.368 11.255 12.134 13.004 13.865

4.900 5.381 5.861 6.338 6.814

16 17 18 19 20

1.173 1.184 1.196 1.208 1.220

0.8528 0.8444 0.8360 0.8277 0.8195

17.258 18.430 19.615 20.811 22.019

0.05794 0.05426 0.05098 0.04805 0.04542

0.06794 0.06426 0.06098 0.05805 0.05542

14.718 15.562 16.398 17.226 18.046

7.288 7.761 8.232 8.702 9.169

21 22 23 24 25

1.232 1.245 1.257 1.270 1.282

0.8114 0.8034 0.7954 0.7876 0.7798

23.239 24.472 25.716 26.973 28.243

0.04303 0.04086 0.03889 0.03707 0.03541

0.05303 0.05086 0.04889 0.04707 0.04541

18.857 19.660 20.456 21.243 22.023

9.635 10.100 10.562 11.024 11.483

26 27 28 29 30

1.295 1.308 1.321 1.335 1.348

0.7720 0.7644 0.7568 0.7493 0.7419

29.526 30.821 32.129 33.450 34.785

0.03387 0.03245 0.03112 0.02990 0.02875

0.04387 0.04245 0.04112 0.03990 0.03875

22.795 23.560 24.316 25.066 25.808

11.941 12.397 12.851 13.304 13.756

35 40 45 50 55

1.417 1.489 1.565 1.645 1.729

0.7059 0.6717 0.6391 0.6080 0.5785

41.660 48.886 56.481 64.463 72.852

0.02400 0.02046 0.01771 0.01551 0.01373

0.03400 0.03046 0.02771 0.02551 0.02373

29.409 32.835 36.095 39.196 42.147

15.987 18.177 20.327 22.436 24.505

60 65 70 75 80

1.817 1.909 2.007 2.109 2.217

0.5504 0.5237 0.4983 0.4741 0.4511

81.670 90.937 100.676 110.913 121.672

0.01224 0.01100 0.00993 0.00902 0.00822

0.02224 0.02100 0.01993 0.01902 0.01822

44.955 47.627 50.169 52.587 54.888

26.533 28.522 30.470 32.379 34.249

85 90 95 100

2.330 2.449 2.574 2.705

0.4292 0.4084 0.3886 0.3697

132.979 144.863 157.354 170.481

0.00752 0.00690 0.00636 0.00587

0.01752 0.01690 0.01636 0.01587

57.078 59.161 61.143 63.029

36.080 37.872 39.626 41.342

1.

144

From Stermole, F J, 1974. Economic Evaluation and Investment Decision Methods. (Investment Evaluations Corporation: Golden, Colo.), by permission.

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 2% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.020 1.040 1.061 1.082 1.104

0.9804 0.9612 0.9423 0.9238 0.9057

1.000 2.020 3.060 4.122 5.204

1.00000 0.49505 0.32675 0.24262 0.19216

1.02000 0.51505 0.34675 0.26262 0.21216

0.980 1.942 2.884 3.808 4.713

— 0.495 0.987 1.475 1.960

6 7 8 9 10

1.126 1.149 1.172 1.195 1.219

0.8880 0.8706 0.8535 0.8368 0.8203

6.308 7.434 8.583 9.755 10.950

0.15853 0.13451 0.11651 0.10252 0.09133

0.17853 0.15451 0.13651 0.02252 0.11133

5.601 6.472 7.325 8.162 8.983

2.442 2.921 3.396 3.868 4.337

11 12 13 14 15

1.243 1.268 1.294 1.319 1.346

0.8043 0.788S 0.7730 0.7579 0.7430

12.169 13.412 14.680 15.974 17.293

0.08218 0.07456 0.06812 0.06260 0.05783

0.10218 0.09456 0.08812 0.08260 0.07783

9.787 10.575 11.348 12.106 12.849

4.802 5.264 5.723 6.179 6.631

16 17 18 19 20

1.373 1.400 1.428 1.457 1.486

0.7284 0.7142 0.7002 0.6864 0.6730

18.639 20.012 21.412 22.841 24.297

0.05365 0.04997 0.04670 0.04378 0.04116

0.07365 0.06997 0.06670 0.06378 0.06116

13.578 14.292 14.992 15.678 16.351

7.080 7.526 7.968 8.407 8.843

21 22 23 24 25

1.516 1.546 1.577 1.608 1.641

0.6598 0.6468 0.6342 0.6217 0.6095

25.783 27.299 28.845 30.422 32.030

0.03878 0.03663 0.03467 0.03287 0.03122

0.05878 0.05663 0.05467 0.05287 0.05122

17.011 17.658 18.292 18.914 19.523

9.276 9.705 10.132 10.555 10.974

26 27 28 29 30

1.673 1.707 1.741 1.776 1.811

0.5976 0.5859 0.5744 0.5631 0.5521

33.671 35.344 37.051 38.792 40.568

0.02970 0.02829 0.02699 0.02578 0.02465

0.04970 0.04829 0.()4699 0.04578 0.04465

20.121 20.707 21.281 21.844 22.396

11.391 11.804 12.214 12.621 13.025

35 40 45 50 55

2.000 2.208 2.438 2.692 2.972

0.5000 0.4529 0.4102 0.3715 0.3365

49.994 60.402 71.893 84.579 98.587

0.02000 0.01656 0.01391 0.01182 0.01014

0.04000 0.03656 0.03391 0.03182 0.03014

24.999 27.355 29.490 31.424 33.175

14.996 16.888 18.703 20.442 22.106

60 65 70 75 80

3.281 3.623 4.000 4.416 4.875

0.3048 0.2761 0.2500 0.2265 0.2051

114.052 131.126 149.987 170.792 193.772

0.00877 0.00763 0.00667 0.00586 0.00516

0.02877 0.02763 0.02667 0.02586 0.02516

34.761 36.197 37.499 38.677 39.745

23.696 25.215 26.663 28.043 29.375

85 90 95 100

5.383 5.943 6.562 7.245

0.1858 0.1683 0.1524 0.1380

219.144 247.157 278.085 312.232

0.00456 0.00405 0.00360 0.00320

0.02456 0.02405 0.02360 0.02320

40.711 41.587 42.380 43.098

30.606 31.793 32.919 33.986

Field Geologists’ Manual

145

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 3%

146

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.030 1.061 1.093 1.126 1.159

0.9709 0.9426 0.9151 0.8885 0.8626

1.000 2.030 3.091 4.184 5.309

1.00000 0.49261 0.32353 0.23903 0.18835

1.03000 0.52261 0.35353 0.26903 0.21835

0.971 1.913 2.829 3.717 4.580

— 0.493 0.980 1.463 1.941

6 7 8 9 10

1.194 1.230 1.267 1.305 1.344

0.8375 0.8131 0.7894 0.7664 0.7441

6.468 7.662 8.892 10.159 11.464

0.15460 0.13051 0.11246 0.09843 0.08723

0.18460 0.16051 0.14246 0.12843 0.11723

5.417 6.230 7.020 7.786 8.530

2.414 2.882 3.345 3.803 4.256

11 12 13 14 15

1.384 1.426 1.469 1.513 1.558

0.7224 0.7014 0.6810 0.6611 0.6419

12.808 14.192 15.618 17.086 18.599

0.07808 0.07046 0.06403 0.05853 0.05377

0.10808 0.10046 0.09403 0.08853 0.08377

9.253 9.954 10.635 11.296 11.938

4.705 5.145 5.587 6.021 6 450

16 17 18 19 20

1.605 1.653 1.702 1.754 1.806

0.6232 0.6050 0.5874 0.5703 0.5537

20.157 21.762 23.414 25.117 26.870

0.04961 0.04595 0.04271 0.03981 0.03722

0.07961 0.07595 0.07271 0.06981 0.06722

12.561 13.166 13.754 14.324 14.877

6.874 7.294 7.708 8.118 8.523

21 22 23 24 25

1.860 1.916 1.974 2.033 2.094

0.5375 0.5219 0.5067 0.4919 0.4776

28.676 30.537 32.453 34.426 36.459

0.03487 0.03275 0.03081 0.02905 0.02743

0.06487 0.06275 0.06081 0.05905 0.05743

15.415 15.937 16.444 16.936 17.413

8.923 9.319 9.709 10.095 10.477

26 27 28 29 30

2.157 2.221 2.288 2.357 2.427

0.4637 0.4502 0.4371 0.4243 0.4120

38.553 40.710 42.931 45.219 47.575

0.02594 0.02456 0.02329 0.02211 0.02102

0.05594 0.05456 0.05329 0.05211 0.05102

17.877 18.327 18.764 19.188 19.600

10.853 11.266 11.593 11.956 12.314

35 40 45 50 55

2.814 3.262 3.782 4.384 5.082

0.3554 0.3066 0.2644 0.2281 0.1968

60.462 75.401 92.720 112.797 136.072

0.01654 0.01326 0.01079 0.00887 0.00735

0.04654 0.04326 0.04079 0.03887 0.03735

21.487 23.115 24.519 25.730 26.774

14.037 15.650 17.156 18.557 19.860

60 65 70 75 80

5.892 6.830 7.918 9.179 10.641

0.1697 0.1464 0.1263 0.1089 0.0940

163.053 194.333 230.594 272.631 321.363

0.00613 0.00515 0.00434 0.00367 0.00311

0.03613 0.03515 0.03434 0.03367 0.03311

27.676 28.453 29.123 29.702 30.201

21.067 22.184 23.215 24.136 25.035

85 90 95 100

12.336 14.300 16.578 19.219

0.0811 0.0699 0.0603 0.0520

377.857 443.349 519.272 607.288

0.00265 0.00226 0.00193 0.00165

0.03265 0.03226 0.03193 0.03165

30.631 31.002 31.323 31.599

25.855 26.567 27.235 27.844

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 4% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.040 1.082 1.125 1.170 1.217

0.9615 0.9246 0.8890 0.8548 0.8219

1.000 2.040 3.122 4.246 5.416

1.00000 0.49020 0.32035 0.23549 0.18463

1.04000 0.53020 0.36035 0.27549 0.22463

0.962 1.886 2.775 3.630 4.452

— 0.490 0.974 1.451 1.922

6 7 8 9 10

1.265 1.316 1.369 1.423 1.480

0.7903 0.7599 0.7307 0.7026 0.6756

6.633 7.898 9.214 10.583 12.006

0.15076 0.12661 0.10853 0.09449 0.08329

0.19076 0.16661 0.14853 0.13449 0.12329

5.242 6.002 6.733 7.435 8.111

2.386 2.843 3.294 3.739 4.177

11 12 13 14 15

1.539 1.601 1.665 1.732 1.801

0.6496 0.6246 0.6006 0.5775 0.5553

13.486 15.026 16.627 18.292 20.024

0.07415 0.06655 0.06014 0.05467 0.04994

0.11415 0.10655 0.10014 0.09467 0.08994

8.760 9.385 9.986 10.563 11.118

4.609 5.034 5.453 5.866 6.272

16 17 18 19 20

1.873 1.948 2.026 2.107 2.191

0.5339 0.5134 0.4936 0.4746 0.4564

21.825 23.698 25.645 27.671 29.778

0.04582 0.04220 0.03899 0.03614 0.03358

0.08582 0.08220 0.07899 0.07614 0.07358

11.652 12.166 12.659 13.134 13.590

6.672 7.066 7.453 7.834 8.209

21 22 23 24 25

2.279 2.370 2.465 2.563 2.666

0.4388 0.4220 0.4057 0.3901 0.3751

31.969 34.248 36.618 39.083 41.646

0.03128 0.02920 0.02731 0.02559 0.02401

0.07128 0.06920 0.06731 0.06559 0.06401

14.029 14.451 14.857 15.247 15.622

8.578 8.941 9.297 9.648 9.993

26 27 28 29 30

2.772 2.883 2.999 3.119 3.243

0.3607 0.3468 0.3335 0.3207 0.3083

44.312 47.084 49.968 52.966 56.085

0.02257 0.02124 0.02001 0.01888 0.01783

0.06257 0.06124 0.06001 0.05888 0.05783

15.983 16.330 16.663 16.984 17.292

10.331 10.664 10.991 11.312 11.627

35 40 45 50 55

3.946 4.801 5.841 7.107 8.646

0.2534 0.2083 0.1712 0.1407 0.1157

73.652 95.026 121.029 152.667 191.159

0.01358 0.01052 0.00826 0.00655 0.00523

0.05358 0.05052 0.04826 0.04655 0.04523

18.665 19.793 20.720 21.482 22.109

13.120 14.476 15.705 16.812 17.807

60 65 70 75 80

10.520 12.799 15.572 18.945 23.050

0.0951 0.0781 0.0642 0.0528 0.0434

237.991 294.968 364.290 448.631 551.245

0.00420 0.00339 0.00275 0.00223 0.00181

0.04420 0.04339 0.04275 0.04223 0.04181

22.623 23.047 23.395 23.680 23.915

18.697 19.491 20.196 20.821 21.372

85 90 95 100

28.044 34.119 41.511 50.505

0.0357 0.0293 0.0241 0.0l98

676.090 827.983 1012.785 1237.624

0.00148 0.00121 0.00099 0.00081

0.04148 0.04121 0.04099 0.04081

24.109 24.267 24.398 24.505

21.857 22.283 22.655 22.980

Field Geologists’ Manual

147

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 5%

148

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n —

1 2 3 4 5

1.050 1.103 1.158 1.216 1.276

0.9524 0.9070 0.8638 0.8227 0.7835

1.000 2.050 3.153 4.310 5.526

1.00000 0.48780 0.31721 0.23201 0.18097

1.05000 0.53780 0.36721 0.28201 0.23097

0.952 1.859 2.723 3.546 4.329

0.488 0.967 1.439 1.902

6 7 8 9 10

1.340 1.407 1.477 1.551 1.629

0.7462 0.7107 0.6768 0.6446 0.6139

6.802 8.142 9.549 11.027 12.578

0.14702 0.12282 0.10472 0.09069 0.07950

0.19702 0.17282 0.15472 0.14069 0.12950

5.076 5.786 6.463 7.108 7.722

2.358 2.805 2.244 3.676 4.099

11 12 13 14 15

1.710 1.796 1.886 1.980 2.079

0.5847 0.5568 0.5303 0.5051 0.4810

14.207 15.917 17.713 19.599 21.579

0.07039 0.06283 0.05646 0.05102 0.04634

0.12039 0.11283 0.10646 0.10102 0.09634

8.306 8.863 9.394 9.899 10.380

4.514 4.922 5.322 5.713 6.097

16 17 18 19 20

2.183 2.292 2.407 2.527 2.653

0.4581 0.4363 0.4155 0.3957 0.3769

23.657 25.840 28.132 30.539 33.066

0.04227 0.03870 0.03555 0.03275 0.03024

0.09227 0.08870 0.08555 0.08275 0.08024

10.838 11.274 11.690 12.085 12.462

6.474 6.842 7.203 7.553 7.903

21 22 23 24 25

2.786 2.925 3.072 3.225 3.386

0.3589 0.3418 0.3256 0.3101 0.2953

35.719 38.505 41.430 44.502 47.727

0.02800 0.02597 0.02414 0.02247 0.02095

0.07800 0.07597 0.07414 0.07247 0.07095

12.821 13.163 13.489 13.799 14.094

8.242 8.573 8.897 9.214 9.524

26 27 28 29 30

3.556 3.733 3.920 4.116 4.322

0.2812 0.2678 0.2551 0.2429 0.2314

51.113 54.669 58.403 62.323 66.439

0.01956 0.01829 0.01712 0.01605 0.01505

0.06956 0.06829 0.06712 0.06605 0.06505

14.375 14.643 14.898 15.141 15.372

9.827 10.112 10.411 10.694 10.969

35 40 45 50 55

5.516 7.040 8.985 11.467 14.636

0.1813 0.1420 0.1113 0.0872 0.0683

90.320 120.800 159.700 209.348 272.713

0.01107 0.00828 0.00626 0.00478 0.00367

0.06107 0.05828 0.05626 0.05478 0.05367

16.374 17.159 17.774 18.256 18.633

12.250 13.377 14.364 15.233 15.966

60 65 70 75 80

18.679 23.840 30.426 38.833 49.561

0.0535 0.0419 0.0329 0.0258 0.0202

353.584 456.798 588.529 756.654 971.229

0.00283 0.00219 0.00170 0.00132 0.00103

0.05283 0.05219 0.05170 0.05132 0.05103

18.929 19.161 19.343 19.485 19.596

16.606 17.154 17.621 18.018 18.353

85 90 95 100

63.254 80.730 103.035 131.501

0.0158 0.0124 0.0097 0.0076

1245.087 1594.607 2040.694 2610.025

0.00080 0.00063 0.00049 0.00038

0.05080 0.05063 0.05049 0.05038

19.684 19.752 19.806 19.848

18.635 18.871 19.069 19.234

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 6% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.060 1.124 1.191 1.262 1.338

0.9434 0.8900 0.8396 0.7921 0.7473

1.000 2.060 3.184 4.375 5.637

1.00000 0.48544 0.31411 0.22859 0.17740

1.06000 0.54544 0.37411 0.28859 0.23740

0.943 1.833 2.673 3.465 4.212

— 0.485 0.961 1.427 1.883

6 7 8 9 10

1.419 1.504 1.594 1.689 1.791

0.7050 0.6651 0.6274 0.5919 0.5584

6.975 8.394 9.897 11.491 13.181

0.14336 0.11914 0.10104 0.08702 0.07587

0.20336 0.17914 0.16104 0.14702 0.13587

4.917 5.582 6.210 6.802 7.360

2.330 2.768 3.195 3.613 4.022

11 12 13 14 15

1.898 2.012 2.133 2.261 2.397

0.5268 0.4970 0.4688 0.4423 0.4173

14.972 16.870 18.882 21.015 23.276

0.06679 0.05928 0.05296 0.04758 0.04296

0.12679 0.11928 0.11296 0.10758 0.10296

7.887 8.384 8.853 9.295 9.712

4.421 4.811 5.192 5.564 5.926

16 17 18 19 20

2.540 2.693 2.854 3.026 3.207

0.3936 0.3714 0.3503 0.3305 0.3118

25.673 28.213 30.906 33.760 36.786

0.03895 0.03544 0.03236 0.02962 0.02718

0.09895 0.09544 0.09236 0.08962 0.08718

10.106 10.477 10.828 11.158 11.470

6.279 6.624 6.960 7.287 7.605

21 22 23 24 25

3.400 3.604 3.820 4.049 4.292

0.2942 0.2775 0.2618 0.2470 0.2330

39.993 43.392 46.996 50.816 54.865

0.02500 0.02305 0.02128 0.01968 0.01823

0.08500 0.08305 0.08128 0.07968 0.07823

11.764 12.042 12.303 12.550 12.783

7.915 8.217 8.510 8.795 9.072

26 27 28 29 30

4.549 4.822 5.112 5.418 5.743

0.2198 0.2074 0.1956 0.1846 0.1741

59.156 63.706 68.528 73.640 79.058

0.01690 0.01570 0.01459 0.01358 0.01265

0.07690 0.07570 0.07459 0.07358 0.07265

13.003 13.211 13.406 13.591 13.765

9.341 9.603 9.857 10.103 10.342

35 40 45 50 55

7.686 10.286 13.765 18.420 24.650

0.1301 0.0972 0.0727 0.0543 0.0406

111.435 154.762 212.744 290.336 394.172

0.00897 0.00646 0.00470 0.00344 0.00254

0.06897 0.06646 0.06470 0.06344 0.06254

14.498 15.046 15.456 15.762 15.991

11.432 12.359 13.141 13.796 14.341

60 65 70 75 80

32.998 44.145 59.076 79.057 105.796

0.0303 0.0227 0.0169 0.0126 0.0095

533.128 719.083 967.932 1300.949 1746.600

0.00188 0.00139 0.00103 0.00077 0.00057

0.06188 0.06139 0.06103 0.06077 0.06057

16.161 16.289 16.385 16.456 16.509

14.791 15.160 15.461 15.706 15.903

85 90 95 100

141.579 189.465 253.546 339.302

0.0071 0.0053 0.0039 0.0029

2342.982 3141.075 4209.104 5638.368

0.00043 0.00032 0.00024 0.00018

0.06043 0.06032 0.06024 0.06018

16.549 16.579 16.601 16.618

16.062 16.189 16.290 16.371

Field Geologists’ Manual

149

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 7%

150

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.070 1.145 1.225 1.311 1.403

0.9346 0.8734 0.8163 0.7629 0.7130

1.000 2.070 3.215 4.440 5.751

1.00000 0.48309 0.31105 0.22523 0.17389

1.07000 0.55309 0.38105 0.29523 0.24389

0.935 1.808 2.624 3.387 4.100

— 0.483 0.955 1.416 1.865

6 7 8 9 10

1.501 1.606 1.718 1.838 1.967

0.6663 0.6227 0.5820 0.5439 0.5083

7.153 8.654 10.260 11.978 13.816

0.13980 0.11555 0.09747 0.08349 0.07238

0.20980 0.18555 0.16747 0.15349 0.14238

4.767 5.389 5.971 6.515 7.024

2.303 2.730 3.147 3.552 3.946

11 12 13 14 15

2.105 2.252 2.410 2.579 2.759

0.4751 0.4440 0.4150 0.3878 0.3624

15.784 17.888 20.141 22.550 25.129

0.06336 0.05590 0.04965 0.04434 0.03979

0.13336 0.12590 0.11965 0.11434 0.10979

7.499 7.943 8.358 8.745 9.108

4.330 4.703 5.065 5.417 5.758

16 17 18 19 20

2.952 3.159 3.380 3.617 3.870

0.3387 0.3166 0.2959 0.2765 0.2584

27.888 30.840 33.999 37.379 40.995

0.03586 0.03243 0.02941 0.02675 0.02439

0.10586 0.10243 0.09941 0.09675 0.09439

9.447 9.763 10.059 10.336 10.594

6.090 6.411 6.722 7.024 7.316

21 22 23 24 25

4.141 4.430 4.741 5.072 5.427

0.2415 0.2257 0.2109 0.1971 0.1842

44.865 49.006 53.436 58.177 63.249

0.02229 0.02041 0.01871 0.01719 0.01581

0.09229 0.09041 0.08871 0.08719 0.08581

10.836 11.061 11.272 11.469 11.654

7.599 7.872 8.137 8.392 8.639

26 27 28 29 30

5.807 6.214 6.649 7.114 7.612

0.1722 0.1609 0.1504 0.1406 0.1314

68.676 74.484 80.698 87.346 94.461

0.01456 0.01343 0.01239 0.01145 0.01059

0.08456 0.08343 0.08239 0.08145 0.08059

11.826 11.987 12.137 12.278 12.409

8.877 9.107 9.329 9.543 9.749

35 40 45 50 55

10.677 14.974 21.002 29.457 41.315

0.0937 0.0668 0.0476 0.0339 0.0242

138.237 199.635 285.749 406.528 575.929

0.00723 0.00501 0.00350 0.00246 0.00174

0.07723 0.07501 0.07350 0.07246 0.07174

12.948 13.332 13.606 13.801 13.940

10.669 11.423 12.036 12.529 12.921

60 65 70 75 80

57.946 81.273 113.989 159.876 224.234

0.0173 0.0123 0.0088 0.0063 0.0045

813.520 1146.755 1614.134 2269.657 3189.063

0.00123 0.00087 0.00062 0.00044 0.00031

0.07123 0.07087 0.07062 0.07044 0.07031

14.039 14.110 14.160 14.196 14.222

13.232 13.476 13.666 13.814 13.927

85 90 95 100

314.500 441.103 618.670 867.716

0.0032 0.0023 0.0016 0.0012

4478.576 6287.185 8823.854 12381.662

0.00022 0.00016 0.00011 0.00008

0.07022 0.07016 0.07011 0.07008

14.240 14.253 14.263 14.269

14.015 14.081 14.132 14.170

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 8% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.080 1.166 1.260 1.360 1.469

0.9259 0.8573 0.7938 0.7350 0.6806

1.000 2.080 3.246 4.506 5.867

1.00000 0.48077 0.30803 0.22192 0.17046

1.08000 0.56077 0.38803 0.30192 0.25046

0.926 1.783 2.577 3.312 3.993

— 0.481 0.949 1.404 1.846

6 7 8 9 10

1.587 1.714 1.851 1.999 2.159

0.6302 0.5835 0.5403 0.5002 0.4632

7.336 8.923 10.637 12.488 14.487

0.13632 0.11207 0.09401 0.08008 0.06903

0.21632 0.19207 0.17401 0.16008 0.14903

4.623 5.206 5.747 6.247 6.710

2.276 2.694 3.098 3.491 3.871

11 12 13 14 15

2.332 2.518 2.720 2.937 3.172

0.4289 0.3971 0.3677 0.3405 0.3152

16.645 18.977 21.495 24.215 27.152

0.06008 0.05270 0.04652 0.04130 0.03683

0.14008 0.13270 0.12652 0.12130 0.11683

7.139 7.536 7.904 8.244 8.559

4.240 4.596 4.940 5.273 5.594

16 17 18 19 20

3.426 3.700 3.996 4.316 4.661

0.2919 0.2703 0.2502 0.2317 0.2145

30.324 33.750 37.450 41.446 45.762

0.03298 0.02963 0.02670 0.02413 0.02185

0.11298 0.10963 0.10670 0.10413 0.10185

8.851 9.122 9.372 9.604 9.818

5.905 6.204 6.492 6.770 7.037

21 22 23 24 25

5.034 5.437 5.871 6.341 6.848

0.1987 0.1839 0.1703 0.1577 0.1460

50.423 55.457 60.893 66.765 73.106

0.01983 0.01803 0.01642 0.01498 0.01368

0.09983 0.09803 0.09642 0.09498 0.09368

10.017 10.201 10.371 10.529 10.675

7.294 7.541 7.779 8.007 8.225

26 27 28 29 30

7.396 7.988 8.627 9.317 10.063

0.1352 0.1252 0.1159 0.1073 0.0994

79.954 87.351 95.339 103.966 113.283

0.01251 0.01145 0.01049 0.00962 0.00883

0.09251 0.09145 0.09049 0.08962 0.08883

10.810 10.935 11.051 11.158 11.258

8.435 8.636 8.829 9.013 9.190

35 40 45 50 55

14.785 21.725 31.920 46.902 68.914

0.0676 0.0460 0.0313 0.0213 0.0145

172.317 259.057 386.506 573.770 848.923

0.00580 0.00386 0.00259 0.00174 0.00118

0.08580 0.08386 0.08259 0.08174 0.08118

11.655 11.925 12.108 12.233 12.319

9.961 10.570 11.045 11.411 11.690

60 65 70 75 80

101.257 148.780 218.606 321.205 471.955

0.0099 0.0067 0.0046 0.0031 0.0021

1253.213 1847.248 2720.080 4002.557 5886.935

0.00080 0.00054 0.00037 0.00025 0.00017

0.08080 0.08054 0.08037 0.08025 0.08017

12.377 12.416 12.443 12.461 12.474

1 1.902 12.060 12.178 12.266 12.330

85 90 95 100

693.456 1018.915 1497.121 2199.761

0.0014 0.0010 0.0007 0.0005

8655.706 12723.939 18701.507 27484.516

0.00012 0.00008 0.00005 0.00004

0.08012 0.08008 0.08005 0.08004

12.482 12.488 12.492 12.494

12.377 12.412 12.436 12.455

Field Geologists’ Manual

151

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 9%

152

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.090 1.188 1.295 1.412 1.539

0.9174 0.8417 0.7722 0.7084 0.6499

1.000 2.090 3.278 4.573 5.985

1.00000 0.47847 0.30505 0.21867 0.16709

1.09000 0.56847 0.39505 0.30867 0.25709

0.917 1.759 2.531 3.240 3.890

— 0.478 0.943 1.393 1.828

6 7 8 9 10

1.677 1.828 1.993 2.172 2.367

0.5963 0.5470 0.5019 0.4604 0.4224

7.523 9.200 1 1.028 13.021 15.193

0.13292 0.10869 0.09067 0.07680 0.06582

0.22292 0.19869 0.18067 0.16680 0.15582

4.486 5.033 5.535 5.995 6.418

2.250 2.657 3.051 3.431 3.798

11 12 13 14 15

2.580 2.813 3.066 3.342 3.642

0.3875 0.3555 0.3262 0.2992 0.2745

17.560 20.141 22.953 26.019 29.361

0.05695 0.04965 0.04357 0.03843 0.03406

0.14695 0.13965 0.13357 0.12843 0.12406

6.805 7.161 7.487 7.786 8.061

4.151 4.491 4.818 5.133 5.435

16 17 18 19 20

3.970 4.328 4.717 5.142 5.604

0.2519 0.2311 0.2120 0.1945 0.1784

33.003 36.974 41.301 46.018 51.160

0.03030 0.02705 0.02421 0.02173 0.01955

0.12030 0.11705 0.11421 0.11173 0.10955

8.313 8.544 8.756 8.950 9.129

5.724 6.002 6.269 6.524 6.767

21 22 23 24 25

6.109 6.659 7.258 7.911 8.623

0.1637 0.1502 0.1378 0.1264 0.1160

56.764 62.873 69.532 76.790 84.701

0.01762 0.01591 0.01438 0.01302 0.01181

0.10762 0.10591 0.10438 0.10302 0.10181

9.292 9.442 9.580 9.707 9.823

7.001 7.223 7.436 7.638 7.832

26 27 28 29 30

9.399 10.245 11.167 12.172 13.268

0.1064 0.0976 0.0895 0.0822 0.0754

93.324 102.723 112.968 124.135 136.307

0.01072 0.00973 0.00885 0.00806 0.00734

0.10072 0.09973 0.09885 0.09806 0.09734

9.929 10.027 10.116 10.198 10.274

8.016 8.191 8.357 8.515 8.666

35 40 45 50 55

20.414 31.409 48.327 74.357 114.408

0.0490 0.0318 0.0207 0.0134 0.0088

215.710 337.882 525.857 815.081 1260.092

0.00464 0.00296 0.00190 0.00123 0.00079

0.09464 0.09296 0.09190 0.09123 0.09079

10.567 10.757 10.881 10.962 11.014

9.308 9.796 10.160 10.430 10.626

60 65 70 75 80

176.031 270.846 416.730 641.191 986.552

0.0057 0.0037 0.0024 0.0016 0.0010

1944.792 2998.288 4619.223 7113.232 10950.574

0.00051 0.00032 0.00022 0.00014 0.00009

0.09051 0.09032 0.09022 0.09014 0.09009

11.048 1 1.070 11.084 11.094 11.100

10.768 10.870 10.943 10.994 11.030

85 90 95 100

1517.932 2335.527 3593.497 5529.041

0.0007 0.0004 0.0003 0.0002

16854.800 25939.184 39916.635 61422.675

0.00006 0.00004 0.00002 0.00002

0.09006 0.09004 0.09002 0.09002

11.104 11.106 11.108 11.109

11.055 11.073 11.085 11.093

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 10% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.100 1.210 1.331 1.464 1.611

0.9091 0.8264 0.7513 0.6830 0.6209

1.000 2.100 3.310 4.641 6.105

1.00000 0.47619 0.30211 0.21547 0.16380

1.10000 0.57619 0.40211 0.31547 0.26380

0.909 1.736 2.487 3.170 3.791

— 0.476 0.937 1.381 1.810

6 7 8 9 10

1.772 1.949 2.144 2.358 2.594

0.5645 0.5132 0.4665 0.4241 0.3855

7.716 9.487 11.436 13.579 15.937

0.12961 0.10541 0.08744 0.07364 0.06275

0.22961 0.20541 0.18744 0.17364 0.16275

4.355 4.868 5.335 5.759 6.144

2.224 2.622 3.004 3.372 3.726

11 12 13 14 15

2.853 3.138 3.452 3.797 4.177

0.3505 0.3186 0.2897 0.2633 0.2394

18.531 21.384 24.523 27.975 31.772

0.05396 0.04676 0.04078 0.03575 0.03147

0.15396 0.14676 0.14078 0.13575 0.13147

6.495 6.814 7.103 7.367 7.606

4.064 4.388 4.699 4.996 5.279

16 17 18 19 20

4.595 5.054 5.560 6.116 6.727

0.2176 0.1978 0.1799 0.1635 0.1486

35.950 40.545 45.599 51.159 57.275

0.02782 0.02466 0.02193 0.01955 0.01746

0.12782 0.12466 0.12193 0.11955 0.11746

7.824 8.022 8.201 8.365 8.514

5.549 5.807 6.053 6.286 6.508

21 22 23 24 25

7.400 8.140 8.954 9.850 10.835

0.1351 0.1228 0.1117 0.1015 0.0923

64.002 71.403 79.543 88.497 98.347

0.01562 0.01401 0.01257 0.01130 0.01017

0.11562 0.11401 0.11257 0.11130 0.11017

8.649 8.772 8.883 8.985 9.077

6.719 6.919 7.108 7.288 7.458

26 27 28 29 30

11.918 13.110 14.421 15.863 17.449

0.0839 0.0763 0.0693 0.0630 0.0573

109.182 121.100 134.210 148.631 164.494

0.00916 0.00826 0.00745 0.00673 0.00608

0.10916 0.10826 0.10745 0.10673 0.10608

9.161 9.237 9.307 9.370 9.427

7.619 7.770 7.914 8.049 8.176

35 40 45 50 55

28.102 45.259 72.890 117.391 189.059

0.0356 0.0221 0.0137 0.0085 0.0053

271.024 442.593 718.905 1163.909 1880.591

0.00369 0.00226 0.00139 0.00086 0.00053

0.10369 0.10226 0.10139 0.10086 0.10053

9.644 9.779 9.863 9.915 9.947

8.709 9.096 9.374 9.570 9.708

60 65 70 75 80

304.482 490.371 789.747 1271.895 2048.400

0.0033 0.0020 0.0013 0.0008 0.0005

3034.816 4893.707 7887.470 12708.954 20474.002

0.00033 0.00020 0.00013 0.00008 0.00005

0.10033 0.10020 0.10013 0.10008 0.10005

9.967 9.980 9.987 9.992 9.995

9.802 9.867 9.911 9.941 9.961

85 90 95

3298.969 5313.023 8556.676

0.0003 0.0002 0.0001

32979.690 53120.226 85556.760

0.00003 0.00002 0.00001

0.10003 0.10002 0.10001

9.997 9.998 9.999

9.974 9.983 9.989

Field Geologists’ Manual

153

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 12%

154

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.120 1.254 1.405 1.574 1.762

0.8929 0.7972 0.7118 0.6355 0.5674

1.000 2.120 3.374 4.779 6.353

1.00000 0.47170 0.29635 0.20923 0.15741

1.12000 0.59170 0.41635 0.32923 0.27741

0.893 1.690 2.402 3.037 3.605

— 0.472 0.925 1.359 1.775

6 7 8 9 10

1.974 2.211 2.476 2.773 3.106

0.5066 0.4523 0.4039 0.3606 0.3220

8.115 10.089 12.300 14.776 17.549

0.12323 0.09912 0.08130 0.06768 0.05698

0.24323 0.21912 0.20130 0.18768 0.17698

4.111 4.564 4.968 5.328 5.650

2.172 2.552 2.913 3.257 3.585

11 12 13 14 15

3.479 3.896 4.363 4.887 5.474

0.2875 0.2567 0.2292 0.2046 0.1827

20.655 24.133 28.029 32.393 37.280

0.04842 0.04144 0.03568 0.03087 0.02682

0.16842 0.16144 0.15568 0.15087 0.14682

5.938 6.194 6.424 6.628 6.811

3.895 4.190 4.468 4.732 4.980

16 17 18 19 20

6.130 6.866 7.690 8.613 9.646

0.1631 0.1456 0.1300 0.1161 0.1037

42.753 48.884 55.750 63.440 72.052

0.02339 0.02046 0.01794 0.01576 0.01388

0.14339 0.14046 0.13794 0.13576 0.13388

6.974 7.120 7.250 7.366 7.469

5.215 5.435 5.643 5.838 6.020

21 22 23 24 25

10.804 12.100 13.552 15.179 17.000

0.0926 0.0826 0.0738 0.0659 0.0588

81.699 92.503 104.603 118.155 133.334

0.01224 0.01081 0.00956 0.00846 0.00750

0.13224 0.13081 0.12956 0.12846 0.12750

7.562 7.645 7.718 7.784 7.843

6.191 6.351 6.501 6.641 6.771

26 27 28 29 30

19.040 21.325 23.884 26.750 29.960

0.0525 0.0469 0.0419 0.0374 0.0334

150.334 169.374 190.699 214.583 241.333

0.00665 0.00590 0.00524 0.00466 0.00414

0.12665 0.12590 0.12524 0.12466 0.12414

7.896 7.943 7.984 8.022 8.055

6.892 7.005 7.110 7.207 7.297

35 40 45 50 55

52.800 93.051 163.988 289.002 509.321

0.0189 0.0107 0.0061 0.0035 0.0020

431.663 767.091 1358.230 2400.018 4236.005

0.00232 0.00130 0.00074 0.00042 0.00024

0.12232 0.12130 0.12074 0.12042 0.12024

8.176 8.244 8.283 8.304 8.317

7.658 7.899 8.057 8.160 8.225

60 65 70 75 80

897.597 1581.872 2787.800 4913.056 8658.483

0.0011 0.0006 0.0004 0.0002 0.0001

7471.641 13173.937 23223.332 40933.799 72145.692

0.00013 0.00008 0.00004 0.00002 0.00001

0.12013 0.12008 0.12004 0.12002 0.12001

8.324 9.328 8.330 8.332 8.333

8.266 8.292 8.308 8.318 8.324

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 15% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.150 1.322 1.521 1.749 2.011

0.8696 0.7561 0.6575 0.5718 0.4972

1.000 2.150 3.472 4.993 6.742

1.00000 0.46512 0.28798 0.20027 0.14832

1.15000 0.61512 0.43798 0.35027 0.29832

0.870 1.626 2.283 2.855 3.352

— 0.465 0.907 1.326 1.723

6 7 8 9 10

2.313 2.660 3.059 3.518 4.046

0.4323 0.3759 0.3269 0.2843 0.2472

8.754 11.067 13.727 16.786 20.304

0.11424 0.09036 0.07285 0.05957 0.04925

0.26424 0.24036 0.22285 0.20957 0.19925

3.784 4.160 4.487 4.772 5.019

2.097 2.450 2.781 3.092 3.383

11 12 13 14 15

4.652 5.350 6.153 7.076 8.137

0.2149 0.1869 0.1625 0.1413 0.1229

24.349 29.002 34.352 40.505 47.580

0.04107 0.03448 0.02911 0.02469 0.02102

0.19107 0.18448 0.17911 0.17469 0.17102

5.234 5.421 5.583 5.724 5.847

3.655 3.908 4.144 4.362 4.565

16 17 18 19 20

9.358 10.761 12.375 14.232 16.367

0.1069 0.0929 0.0808 0.0703 0.0611

55.717 65.075 75.836 88.212 102.444

0.01795 0.01537 0.01319 0.01134 0.00976

0.16795 0.16537 0.16319 0.16134 0.15976

5.954 6.047 6.128 6.198 6.259

4.752 4.925 5.084 5.231 5.365

21 22 23 24 25

18.822 21.645 24.891 28.625 32.919

0.0531 0.0462 0.0402 0.0349 0.0304

118.810 137.632 159.276 184.168 212.793

0.00842 0.00727 0.00628 0.00543 0.00470

0.15842 0.15727 0.15628 0.15543 0.15470

6.312 6.359 6.399 6.434 6.464

5.488 5.601 5.704 5.798 5.883

26 27 28 29 30

37.857 43.535 50.066 57.575 66.212

0.0264 0.0230 0.0200 0.0174 0.0151

245.712 283.569 327.104 377.170 434.745

0.00407 0.00353 0.00306 0.00265 0.00230

0.15407 0.15353 0.15306 0.15265 0.15230

6.491 6.514 6.534 6.551 6.566

5.961 6.032 6.096 6.154 6.207

35 40 45 50 55

133.176 267.864 538.769 1083.657 2179.622

0.0075 0.0037 0.0019 0.0009 0.0005

881.170 1779.090 3585.128 7217.716 14524.148

0.00113 0.00056 0.00028 0.00014 0.00007

0.15113 0.15056 0.15028 0.15014 0.15007

6.617 6.642 6.654 6.661 6.664

6.402 6.517 6.583 6.620 6.641

60 65

4383.999 8817.787

0.0002 0.0001

29219.992 58778.583

0.00003 0.00002

0.15003 0.15002

6.665 6.666

6.653 6.659

Field Geologists’ Manual

155

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 20%

156

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.200 1.440 1.728 2.074 2.488

0.8333 0.6944 0.5787 0.4823 0.4019

1.000 2.200 3.640 5.368 7.442

1.00000 0.45455 0.27473 0.18629 0.13438

1.20000 0.65455 0.47473 0.38629 0.33438

0.833 1.528 2.106 2.589 2.991

— 0.455 0.879 1.274 1.641

6 7 8 9 10

2.986 3.583 4.300 5.160 6.192

0.3349 0.2791 0.2326 0.1938 0.1615

9.930 12.916 16.499 20.799 25.959

0.10071 0.07742 0.06061 0.04808 0.03852

0.30071 0.27742 0.26061 0.24808 0.23852

3.326 3.605 3.837 4.031 4.192

1.979 2.290 2.576 2.836 3.074

11 12 13 14 15

7.430 8.916 10.699 12.839 15.407

0.1346 0.1122 0.0935 0.0779 0.0649

32.150 39.581 48.497 59.196 72.035

0.03110 0.02526 0.02062 0.01689 0.01388

0.23110 0.22526 0.22062 0.21689 0.21388

4.327 4.439 4.533 4.611 4.675

3.289 3.484 3.660 3.818 3.959

16 17 18 19 20

18.488 22.186 26.623 31.948 38.338

0.0541 0.0451 0.0376 0.0313 0.0261

87.442 105.931 128.117 154.740 186.688

0.01144 0.00944 0.00781 0.00646 0.00536

0.21144 0.20944 0.20781 0.20646 0.20536

4.730 4.775 4.812 4.843 4.870

4.085 4.198 4.298 4.386 4.464

21 22 23 24 25

46.005 55.206 66.247 79.497 95.396

0.0217 0.0181 0.0151 0.0126 0.0105

225.026 271.031 326.237 392.484 471.981

0.00444 0.00369 0.00307 0.00255 0.00212

0.20444 0.20369 0.20307 0.20255 0.20212

4.891 4.909 4.925 4.937 4.948

4.533 4.594 4.648 4.694 4.735

26 27 28 29 30

114.475 137.371 164.845 197.814 237.376

0.0087 0.0073 0.0061 0.0051 0.0042

567.377 681.853 819.223 984.068 1181.882

0.00176 0.00147 0.00122 0.00102 0.00085

0.20176 0.20147 0.20122 0.20102 0.20085

4.956 4.964 4.970 4.975 4.979

4.771 4.802 4.829 4.853 4.873

35 40 45 50

590.668 1469.772 3657.262 9100.438

0.0017 0.0007 0.0003 0.0001

2948.341 7343.858 18281.310 45497.191

0.00034 0.00014 0.00005 0.00002

0.20034 0.20014 0.20005 0.200Q2

4.992 4.997 4.999 4.999

4.941 4.973 4.988 4.994

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 25% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.250 1.562 1.953 2.441 3.052

0.8000 0.6400 0.5120 0.4096 0.3277

1.000 2.250 3.812 5.766 8.207

1.00000 0.44444 0.26230 0.17344 0.12185

1.25000 0.69444 0.51230 0.42344 0.37185

0.800 1.440 1.952 2.362 2.689

— 0.444 0.852 1.225 1.563

6 7 8 9 10

3.815 4.768 5.960 7.451 9.313

0.2621 0.2097 0.1678 0.1342 0.1074

11.259 15.073 19.842 25.802 33.253

0.08882 0.06634 0.05040 0.03876 0.03007

0.33882 0.31634 0.30040 0.28876 0.28007

2.951 3.161 3.329 3.463 3.571

1.868 2.142 2.387 2.605 2.797

11 12 13 14 15

11.642 14.552 18.190 22.737 28.422

0.0859 0.0687 0.0550 0.0440 0.0352

42.566 54.208 68.760 86.949 109.687

0.02349 0.01845 0.01454 0.01150 0.00912

0.27349 0.26845 0.26454 0.26150 0.25912

3.656 3.725 3.780 3.824 3.859

2.966 3.114 3.244 3.356 3.453

16 17 18 19 20

35.527 44.409 55.511 69.389 86.736

0.0281 0.0225 0.0180 0.0144 0.0115

138.109 173.636 218.045 273.556 342.945

0.00724 0.00576 0.00459 0.00366 0.00292

0.25724 0.25576 0.25459 0.25366 0.25292

3.887 3.910 3.928 3.942 3.954

3.537 3.608 3.670 3.722 3.767

21 22 23 24 25

108.420 135.525 169.407 211.758 264.698

0.0092 0.0074 0.0059 0.0047 0.0038

429.681 538.101 673.626 843.033 1054.791

0.00233 0.00186 0.00148 0.00119 0.00095

0.25233 0.25186 0.25148 ~.25119 0.25095

3.963 3.970 3.976 3.981 3.985

3.805 3.836 3.863 3.888 3.905

26 27 28 29 30

330.872 413.590 516.988 646.235 807.794

0.0030 0.0024 0.0019 0.0015 0.0012

1319.489 1650.361 2063.952 2580.939 3227.174

0.00076 0.00061 0.00048 0.00039 0.00031

0.25076 0.25061 0.25048 0.25039 0.25031

3.988 3.990 3.992 3.994 3.995

3.921 3.935 3.946 3.955 3.963

35 40

2465.190 7523.164

0.0004 0.0001

9856.761 30088.655

0.00010 0.00003

0.25010 0.25003

3.998 3.999

3.986 3.995

Field Geologists’ Manual

157

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 30%

158

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.300 1.690 2.197 2.856 3.713

0.7692 0.5917 0.4552 0.3501 0.2693

1.000 2.300 3.900 6.187 9.043

1.00000 0.43478 0.25063 0.16163 0.11058

1.30000 0.73478 0.55063 0.46163 0.41058

0.769 1.361 1.816 2.166 2.436

— 0.435 0.827 1.178 1.490

6 7 8 9 10

4.827 6.275 8.157 10.604 13.786

0.2072 0.1594 0.1226 0.0943 0.0725

12.756 17.583 23.858 32.015 42.619

0.07839 0.05687 0.04192 0.03124 0.02346

0.37839 0.35687 0.34192 0.33124 0.32346

2.643 2.802 2.925 3.019 3.092

1.765 2.006 2.216 2.396 2.551

11 12 13 14 15

17.922 23.298 30.288 39.374 51.186

0.0558 0.0429 0.0330 0.0254 0.0195

56.405 74.327 97.625 127.913 167.286

0.01773 0.01345 0.01024 0.00782 0.00598

0.31773 0.31345 0.31024 0.30782 0.30598

3.147 3.190 3.223 3.249 3.268

2.683 2.795 2.890 2.968 3.034

16 17 18 19 20

66.542 86.504 112.455 146.192 190.050

0.0150 0.0116 0.0089 0.0068 0.0053

218.472 285.014 371.518 483.973 630.165

0.00458 0.00351 0.00269 0.00207 0.00159

0.30458 0.30351 0.30269 0.30207 0.30159

3.283 3.295 3.304 3.311 3.316

3.089 3.135 3.172 3.202 3.228

21 22 23 24 25

247.065 321.184 417.539 542.801 705.641

0.0040 0.0031 0.0024 0.0018 0.0014

820.215 1067.280 1388.464 1806.003 2348.803

0.00122 0.00094 0.00072 0.00055 0.00043

0.30122 0.30094 0.30072 0.30055 0.30043

3.320 3.323 3.325 3.327 3.329

3.248 3.265 3.278 3.289 3.298

26 27 28 29 30

917.333 1192.533 1550.293 2015.381 2619.996

0.0011 0.0008 0.0006 0.0005 0.0004

3054.444 3971.778 5164.311 6714.604 8729.985

0.00033 0.00025 0.00019 0.00015 0.00011

0.30033 0.30025 0.30019 0.30015 0.30011

3.330 3.331 3.331 3.332 3.332

3.305 3.311 3.315 3.319 3.322

35

9727.860

0.0001

32422.868

0.00003

0.30003

3.333

3.330

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 40% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.400 1.960 2.744 3.842 5.378

0.7143 0.5102 0.3644 0.2603 0.1859

1.000 2.400 4.360 7.104 10.946

1.00000 0.41667 0.22936 0.14077 0.09136

1.40000 0.81667 0.62936 0.54077 0.49136

0.714 1.224 1.589 1.849 2.035

— 0.417 0.780 1.092 1.358

6 7 8 9 10

7.530 10.541 14.758 20.661 28.925

0.1328 0.0949 0.0678 0.0484 0.0346

16.324 23.853 34.395 49.153 69.814

0.06126 0.04192 0.02907 0.02034 0.01432

0.46126 0.44192 0.42907 0.42034 0.41432

2.168 2.263 2.331 2.379 2.414

1.581 1.766 1.919 2.042 2.142

11 12 13 14 15

40.496 56.694 79.371 111.120 155.568

0.0247 0.0176 0.0126 0.0090 0.0064

98.739 139.235 195.929 275.300 386.420

0.01013 0.00718 0.00510 0.00363 0.00259

0.41013 0.40718 0.40510 0.40363 0.40259

2.438 2.456 2.469 2.478 2.484

2.222 2.284 2.334 2.373 2.403

16 17 18 19 20

217.795 304.913 426.879 597.630 836.683

0.0046 0.0033 0.0023 0.0017 0.0012

541.988 759.784 1064.697 1491.576 2089.206

0.00185 0.00132 0.00094 0.00067 0.00048

0.40185 0.40132 0.40094 0.40067 0.40048

2.489 2.492 2.494 2.496 2.497

2.426 2.444 2.458 2.468 2.476

21 22 23 24 25

1171.356 1639.898 2295.857 3214.200 4499.880

0.0009 0.0006 0.0004 0.0003 0.0002

2925.889 4097.245 5737.142 8032.999 11247.199

0.00034 0.00024 0.00017 0.00012 0.00009

0.40034 0.40024 0.40017 0.40012 0.40009

2.498 2.498 2.499 2.499 2.499

2.482 2.487 2.490 2.492 2.494

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.500 2.250 3.375 5.062 7.594

0.6667 0.4444 0.2963 0.1975 0.1317

1.000 2.500 4.750 8.125 13.188

1.00000 0.40000 0.21053 0.12308 0.07583

1.50000 0.90000 0.71053 0.62308 0.57583

0.667 1.111 1.407 1.605 1.737

— 0.400 0.737 1.015 1.242

6 7 8 9 10

11.391 17.086 25.629 38.443 57.665

0.0878 0.0585 0.0390 0.0260 0.0173

20.781 32.172 49.258 74.887 113.330

0.04812 0.03108 0.02030 0.01335 0.00882

0.54812 0.53108 0.52030 0.51335 0.50882

1.824 1.883 1.922 1.948 1.965

1.423 1.565 1.675 1.760 1.824

11 12 13 14 15

86.498 129.746 194.620 291.929 437.894

0.0116 0.0077 0.0051 0.0034 0.0023

170.995 257.493 387.239 581.859 873.788

0.00585 0.00388 0.00258 0.00172 0.00114

0.50585 0.50388 0.50258 0.50172 0.50114

1.977 1.985 1.990 1.993 1.995

1.871 1.907 1.933 1.952 1.966

16 17 18 19 20

656.841 985.261 1477.892 2216.838 3325.257

0.0015 0.0010 0.0007 0.0005 0.0003

1311.682 1968.523 2953.784 4431.676 6648.513

0.00076 0.00051 0.00034 0.00023 0.00015

0.50076 0.50051 0.50034 0.50023 0.50015

1.997 1.998 1.999 1.999 1.999

1.976 1.983 1.988 1.991 1.994

i = 50%

Field Geologists’ Manual

159

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 70% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.700 2.890 4.913 8.352 14.199

0.5882 0.3460 0.2035 0.1197 0.0704

1.000 2.700 5.590 10.503 18.855

1.0000 0.3704 0.1789 0.0952 0.0530

1.7000 1.0704 0.8789 0.7952 0.7530

0.5882 0.9342 1.1378 1.2575 1.3280

— 0.3703 0.6619 0.8845 1.0497

6 7 8 9 10

24.138 41.034 69.758 118.590 201.600

0.0414 0.0244 0.0143 0.0084 0.0050

33.054 57.191 98.225 167.980 286.570

0.0302 0.0175 0.0102 0.0060 0.0035

0.7302 0.7175 0.7102 0.7060 0.7035

1.3694 1.3938 1.4081 1.4165 1.4215

1.1693 1.2537 1.3122 1.3520 1.3787

11 12 13 14 15

342.720 582.620 990.460 1684. 2862.

0.0029 0.0017 0.0010 0.0006 0.0003

488.170 830.890 1413. 2404. 4087.

0.0020 0.0012 0.0007 0.0004 0.0002

0.7020 0.7012 0.7007 0.7004 0.7002

1.4244 1.4261 1.4271 1.4277 1.4281

1.3964 1.4079 1.4154 1.4203 1.4233

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

1.900 3.610 6.859 13.032 24.761

0.5263 0.2770 0.1458 0.0767 0.0404

1.000 2.900 6.510 13.369 26.401

1.0000 0.3448 0.1536 0.0748 0.0379

1.9000 1.2448 1.0536 0.9748 0.9379

0.5263 0.8033 0.9491 1.0259 1.0662

— 0.3448 0.5991 0.7787 0.9007

6 7 8 9 10

47.046 89.387 169.84 322.69 613.11

0.0213 0.0112 0.0059 0.0031 0.0016

51.162 98.208 187.60 357.43 680.12

0.0195 0.0102 0.0053 0.0028 0.0015

0.9195 0.9102 0.9053 0.9028 0.9015

1.0875 1.0987 1.1046 1.1077 1.1093

0.9808 1.0319 1.0637 1.0831 1.0948

0.0008 0.0004 0.0002 0.0001 0.0001

0.9008 0.9004 0.9002 0.9001 0.9001

1.1102 1.1106 1.1108 1.1110 1.1110

1.1017 1.1057 1.1080 1.1094 1.1101

i = 90%

11 12 13 14 15

1165. 2213. 4205. 7990. 15181.

0.0009 0.0004 0.0002 0.0001 0.0001

1293. 2458. 4671. 8877. 16867.

i = 110%

160

n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

2.100 4.410 9.261 19.448 40.841

0.4762 0.2268 0.1080 0.0514 0.0245

1.000 3.100 7.510 16.771 36.219

1.0000 0.3226 0.1332 0.0596 0.0276

2.100 1.423 1.233 1.160 1.128

0.4762 0.7029 0.8109 0.8623 0.8868

— 0.3226 0.5459 0.6923 0.7836

6 7 8 9 10

85.766 180.11 378.23 794.28 1668.

0.0117 0.0055 0.0026 0.0013 0.0006

77.060 162.83 342.93 721.16 1515.

0.0130 0.0061 0.0029 0.0014 0.0007

1.113 1.106 1.103 1.101 1.101

0.8985 0.9040 0.9067 0.9079 0.9085

0.8383 0.8700 0.8879 0.8978 0.9031

11 12

3503. 7356.

0.0003 0.0001

3183. 6686.

0.0003 0.0001

1.100 1.100

0.9088 0.9090

0.9059 0.9075

Field Geologists’ Manual

MINING AND ECONOMIC GEOLOGY

TABLE OF COMPOUND INTEREST FACTORS—continued i = 130% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

2.300 5.290 12.167 27.984 64.363

0.4348 0.1890 0.0822 0.0357 0.0155

1.000 3.300 8.590 20.757 48.741

1.0000 0.3030 0.1164 0.0482 0.0205

2.300 1.603 1.416 1.348 1.320

0.4348 0.6239 0.7060 0.7417 0.7573

— 0.3030 0.5006 0.6210 0.6903

6 7 8 9 10

148.04 340.48 783.11 1801. 4143.

0.0068 0.0029 0.0013 0.0006 0.0002

113.10 261.14 601.62 1385. 3186.

0.0088 0.0038 0.0017 0.0007 0.0003

1.309 1.304 1.302 1.301 1.300

0.7640 0.7670 0.7682 0.7688 0.7690

0.7284 0.7486 0.7590 0.7642 0.7668

11 12

9528. 21915.

0.0001 0.0001

0.0001 0.0001

1.300 1.300

0.7691 0.7692

0.7681 0.7687

7328. 16857.

i = 150% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

2.500 6.250 15.625 39.062 97.656

0.4000 0.1600 0.0640 0.0256 0.0102

1.000 3.500 9.750 25.375 64.437

1.000 0.2857 0.1026 0.0394 0.0155

2.500 1.786 1.603 1.539 1.515

0.4000 0.5600 0.6240 0.6496 0.6598

— 0.16000 0.28800 0.36480 0.40576

6 7 8 9 10

244.14 610.35 1526. 3815. 9537.

0.0041 0.0016 0.0007 0.0003 0.0001

162.09 406.23 1017. 2542. 6357.

0.0062 0.0025 0.0010 0.0004 0.0002

1.506 1.502 1.501 1.500 1.500

0.6639 0.6656 0.6662 0.6665 0.6666

0.42624 0.43607 0.44066 0.44276 0.44370

0.0001 0.0000

1.500 1.500

0.6666 0.6667

0.44412 0.44430

11 12

23842. 59604.

0.0000 0.0000

15894. 39736.

i = 200% n

F/Pi,n

P/Fi,n

F/Ai,n

A/Fi,n

A/Pi,n

P/Ai,n

A/Gi,n

1 2 3 4 5

3.000 9.000 27.000 81.000 243.000

0.33333 0.11111 0.03704 0.01235 0.00412

1.000 4.000 13.000 40.000 121.000

1.000 0.25000 0.07692 0.02500 0.00826

3.000 2.250 2.077 2.025 2.008

0.3333 0.4444 0.4815 0.4938 0.4979

— 0.25000 0.38462 0.45000 0.47934

6 7 8 9 10

729.000 2187.000 6561.000 19683.000 59049.000

0.00137 0.00046 0.00015 0.00005 0.00002

364.000 1093.000 3280.000 9841.000 29524.000

0.00275 0.00092 0.00030 0.00010 0.00003

2.003 2.001 2.000 2.000 2.000

0.4993 0.4998 0.4999 0.5000 0.5000

0.49176 0.49680 0.49878 0.49954 0.49983

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4.8. INGREDIENTS, METHODS AND STAGES IN MINERAL EXPLORATION

MINING AND ECONOMIC GEOLOGY

162

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4.9. BACKGROUND DATA FOR A MINE EVALUATION The following details are those which may be required to determine the value of a small to medium scale mine on a professional basis. The vendor may not be able to supply all the information listed, in which case these items should be checked at the time of the initial property inspection. 1. TITLES AND PERMITS Photocopies of all mining titles and permits (perhaps permits to draw water, use local roads, cut timber from State forests, discharge tailings, store explosives, etc). Details of all rentals, rates etc. Copies of compensation agreements with landowners if appropriate. Name, address and telephone number of the appropriate Shire Engineer, Mining Warden and Inspector of Mines, and photocopies of relevant correspondence. Name, address and telephone number of the owner(s) of the surrounding land. Form of land tenure (eg unoccupied Crown land, State forest, grazing licence, freehold) and land usage (eg natural forest, natural pasture, improved pasture, cropping). 2. ORE RESERVES Photocopies of all relevant geological reports including details of all samples (location, type, analyses) which support the ore reserve calculations. All relevant geological plans and sections, including level and stope assay plans, and reports on ore treatment testing. 3. MINE WORKINGS Detailed plans and sections showing ore extracted to date. The long term development plan, showing ore and waste to be mined each period, including an estimate of dilution if available. Records of past mine production on a daily tonnes and grade basis, and mullock removed per period. Details of the mullock storage system. A description of all mining equipment, categorised by maker’s name, year of manufacture, equipment type, model number, condition, hourly output and valuation for sale. List maintenance time and cost for each unit per period, spare parts carried, and an estimate of availability for major production units. Water pumped from the mine and cost on a daily or period basis. Charges for contract mining (if appropriate), and average daily and period ore and waste output.

Field Geologists’ Manual

4. ORE TREATMENT Description of ore cartage system from mine to mill, plus details of ore stockpiles. A flow sheet of the ore treatment system, with average throughput, and details of all units of machinery as for the mining equipment. Costs and downtime for maintenance and major spares held. Records of ore treated (tonnes and grade) and reconciliation with mine figures. Details of product recovery, reagent usage, labour costs and maintenance costs. Details of concentrate storage, and of tailings disposal. Sources of water, power, timber etc and period costs. 5. EMPLOYEES Total work force and employees per shift, listed by individual duty, with individual gross pay rates. Non-cash employee benefits charged to the mine (eg housing, meals). Overhead costs. 6. FURTHER PROCESSING Ore or concentrate transport system and costs per t or kg. Processing costs per unit and per cent recovery of saleable product. 7. PRODUCT SALES Method of sales of mine products including copies of sales contracts if appropriate. Records of sales over the mine’s life. 8. FINANCIAL RECORDS Mine costs, income, royalties etc preferably as copies of audited annual accounts, plus details of any outstanding loans, mortgages etc. 9. PROPOSED TERMS The draft agreement of sale, farmout, tribute or whatever mechanism is contemplated, including the name, address and equity of all owners. Time available for testing/evaluation prior to completion of the purchase. MINE INSPECTION Systematic check lists for the examination of a mining property are provided in Peters, W C, 1978. Exploration and Geology (John Wiley: New York), pp 619-624; in Hayes, C W, 1921. Handbook for Field Geologists (John Wiley: New York), pp 84-136; and in Banfield, A F, 1972. Ore reserves, feasibility studies and valuations of mineral properties, AIME Annual Meeting—San Francisco, February 1972, Preprint 72-AK-87 (Society of Mining Engineers of AIME:

163

MINING AND ECONOMIC GEOLOGY

New York). Mine evaluation methods and objectives are described in McKinstry, H E, 1948. Mining Geology (Prentice Hall: New York), pp 428-502. None of these advises the valuer to

check the position of the lease pegs in relation to the mine assets, which experience teaches is essential in Australia.

4.10. SELECTED BIBLIOGRAPHY Australasian Institute of Mining and Metallurgy publications: Eighth Commonwealth Mining and Metallurgical Congress, Australia and New Zealand, 1965. Vol: 1.

Geology of Australian Ore Deposits.

2.

Exploration and Mining Geology.

3.

The Australian Mining, Metallurgical and Mineral Industry.

5.

Proceedings (Petroleum).

6.

Proceedings (General).

Monograph 5, Economic Geology of Australia and Papua New Guinea—Metals, (Ed C L Knight), 1975. Monograph 6, Economic Geology of Australia and Papua New Guinea—Coal, (Eds D M Traves and D King), 1975. Monograph 7, Economic Geology of Australia and Papua New Guinea—Petroleum, (Eds R B Leslie, H J Evans and C L Knight), 1976. Monograph 8, Economic Geology of Australia and Papua New Guinea—Industrial Minerals and Rocks, (Ed C L Knight), 1976. Monograph 14, Geology of the Mineral Deposits of Australia and Papua New Guinea, (Ed F E Hughes), 1990. Monograph 17, Geological Aspects of the Discovery of Some Important Mineral Deposits in Australia, (Ed K R Glasson and J H Rattigan), 1990. Monograph 22, Geology of Australian and Papua New Guinean Ore Deposits, (Ed D A Berkman and D H Mackenzie), 1998. Monograph 23, Mineral Resource and Ore Reserve Estimation—The AusIMM Guide to Good Practice, (2001). Australian Mineral Foundation course notes: Geology and Exploration for Non-Geologists (Minerals). Improving the Chance of Exploration Success. Petroleum Geology and Exploration for Non-Geologists.

164

Economic Evaluation and Investment Decision Methods for Resource Projects. Sampling for Ore Reserves and Ore Grade Control. Sampling for Reconciliation between Mine and Mill. Management for the Mining Sector. GIS: Decision Support Systems for Mineral Exploration. Prediction of Undiscovered Mineral Deposits. New Generation Gold Mines Series (case histories of discoveries), 1995, 1997, 1999. Porphyry and Hydrothermal Copper and Gold Deposits, 1998. Hydrothermal Iron-Oxide Copper-Gold and Related Deposits, 2001. Berger, B R and Bethke, P M (Eds), 1986. Geology and Geochemistry of Epithermal Systems, Reviews in Economic Geology, Vol 2 (Society of Economic Geologists: Chelsea, MI) Carr, D D (Ed), 1994. Industrial Minerals and Rocks, 6th edition (Society for Mining, Metallurgy and Exploration, Inc: Littleton, CO). Cox, D P and Singer, D A (Eds), 1986. Mineral Deposit Models, US Geological Survey Bulletin 1693 (US Government Printing Office: Washington, DC) Guilbert, J M and Park, C F Jr, 1986. The Geology of Ore Deposits (W H Freeman and Co: New York) Laznicka, P, 1985. Empirical Metallogeny, Vol 1, Phanerozoic Environments, Associations and Deposits, Developments in Economic Geology 19 (Elsevier: Amsterdam). McKinstry, H E, 1948. Mining Geology (Prentice Hall: New York) Peele, R (Ed), 1945. Mining Engineers’ Handbook, 2 Vols (John Wiley and Sons: New York). Peters, W C, 1978. Exploration and Mining Geology (John Wiley and Sons: New York). Pirajno, F, 1992. Hydrothermal Mineral Deposits—Principles and Fundamental Concepts for the Exploration Geologist (Springer-Verlag: Berlin). Whiting, B H, Mason, R and Hodgson, C J (Eds), 1992. Giant Ore Deposits (Dept of Geological Sciences, Queen’s University: Kinston, Ontario).

Field Geologists’ Manual

5. GEOLOGICAL MAPPING 5.1. INDEX TO AUSTRALIAN, NEW ZEALAND, AND PAPUA NEW GUINEA 1:250 000 SCALE MAPS SHOWING MAGNETIC DECLINATION

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166

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168

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5.2. SUPPLIERS OF GEOLOGICAL AND TOPOGRAPHIC MAPS AND AIR PHOTOGRAPHS ANTARCTICA AND AUSTRALIA Geological Maps Australian Geological Survey Organisation, GPO Box 378, CANBERRA, ACT 2601 Internet: www.agso.gov.au Topographic Maps and Aerial Photographs Australian Surveying and Land Information Group, (AUSLIG), PO Box 2, BELCONNEN, ACT 2616, Internet: www.auslig.gov.au

Aerial Photos: New Zealand Aerial Mapping Ltd, PO Box 300-322, ALBANY, NZ Internet: www.nzam.com LANDSAT and Other Images ACRES (Australian Centre for Remote Sensing), PO Box 2, BELCONNEN, ACT 2616 Internet: www.auslig.gov.au

NORTHERN TERRITORY Geological Maps

LANDSAT and Other Images (Australia wide) ACRES (Australian Centre for Remote Sensing), PO Box 2, BELCONNEN, ACT 2616 Internet: [email protected] NEW SOUTH WALES

Dept of Mines and Energy, PO Box 2091, DARWIN, NT 0800 Topographic Maps and Aerial Photographs Dept of Lands, Planning and Environment, Cnr Bennett and Cavanagh Streets, DARWIN, NT 0822

Geological Maps Information and Customer Services, Dept of Mineral Resources, PO Box 536, ST LEONARDS, NSW 1590 Topographic Maps and Aerial Photographs Land Information Centre, Dept of Land and Water Conservation, GPO Box 39, SYDNEY, NSW 2001 Internet: www.dlwc.nsw.gov.au NEW ZEALAND

PAPUA NEW GUINEA Geological Maps Geological Survey Division, Dept of Mining and Petroleum, PO Box 778, PORT MORESBY, PNG Topographic Maps and Aerial Photographs Australian Surveying and Land Information Group, (AUSLIG), PO Box 2, BELCONNEN, ACT 2616 Internet: www.auslig.gov.au

Geological Maps Institute of Geological and Nuclear Sciences, 69 Gracefield Rd, LOWER HUTT, NZ Internet: www.gns.cri.nz Postal Address: PO Box 30-368, LOWER HUTT, NZ Topographic Maps and Aerial Photographs Topo maps: Land Information New Zealand, Private Box 5501, WELLINGTON, NZ Internet: www.linz.govt.nz

Field Geologists’ Manual

LANDSAT and Other Images ACRES (Australian Centre for Remote Sensing), PO Box 2, BELCONNEN, ACT 2616 Internet: www.auslig.gov.au

QUEENSLAND Geological Maps Dept of Mines and Energy, GPO Box 194, BRISBANE, QLD 4001 Internet: www.dme.qld.gov.au

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GEOLOGICAL MAPPING

Topographic Maps and Aerial Photographs Land Centre, Dept of Natural Resources, Cnr Vulture and Main Streets, WOOLLOONGABBA, QLD 4102 Internet: www.dnr.qld.gov.au

SOUTH AUSTRALIA Geological Maps Mines and Energy Resources, Dept for Primary Industries and Resources, GPO Box 2355, ADELAIDE SA 5001 Topographic Maps and Aerial Photographs Mapland, Building 2, 300 Richmond Street, NETLEY, SA 5037 Internet: www.dehaa.sa.gov.au/rres_inform

TASMANIA Geological Maps Mineral Resources Tasmania, 30 Gordons Hill Road, ROSNY PARK, TAS 7018 Internet: www.mrt.tas.gov.au Postal Address: PO Box 56 ROSNY PARK, TAS 7018 Topographic Maps and Aerial Photographs Information and Land Services, 134 Macquarie Street, HOBART, TAS 7000

170

Postal Address: GPO Box 44A, HOBART, TAS 7001

VICTORIA Geological Maps Dept of Natural Resources and Environment, PO Box 500, EAST MELBOURNE, VIC 3002 Topographic Maps and Aerial Photographs Topo maps: Information Victoria, 356 Collins Street, MELBOURNE, VIC 3000 Internet: www.information.vic.gov.au Air photos: AUSLIG (see Australia entry) or Vicimage (QASCO) Pty Ltd, 171 Clarendon Street, SOUTHBANK, VIC 3006 WESTERN AUSTRALIA Geological Maps Dept of Minerals and Energy, 100 Plain Street, EAST PERTH, WA 6004 Internet: www.dme.wa.gov Topographic Maps and Aerial Photographs Central Map Agency, Dept of Land Administration, 1 Midland Square, MIDLAND, WA 6056 Internet: www.landonline.com.au

Field Geologists’ Manual

GEOLOGICAL MAPPING

1

5.3.1. LENGTHS OF DEGREES OF THE PARALLEL AND MERIDIAN AND CONVERSION TO THE GEOCENTRIC DATUM OF AUSTRALIA LENGTHS OF DEGREES OF THE PARALLEL LAT.

1

METRES

STATUTE MILES

LAT.

METRES

STATUTE MILES

LAT.

METRES

STATUTE MILES

° ' 0 00 l 00 2 00 3 00 4 00 5 00 6 00 7 00 8 00 9 00

111 321 111 304 111 253 111 169 111 051 110 900 110 715 110 497 110 245 109 959

69.172 69.162 69.130 69.078 69.005 68.911 68.795 68.660 68.504 68.326

° ' 30 00 31 00 32 00 33 00 34 00 35 00 36 00 37 00 38 00 39 00

96 488 95 506 94 495 93 455 92 387 91 290 90 166 89 014 87 835 86 629

59.956 59.345 58.716 58.071 57.407 56.725 56.027 55.311 54.579 53.829

° ' 60 00 61 00 62 00 63 00 64 00 65 00 66 00 67 00 68 00 69 00

55 802 54 110 52 400 50 675 48 934 47 177 45 407 43 622 41 823 40 012

34.674 33.623 32.560 31.488 30.406 29.315 28.215 27.106 25.988 24.862

10 00 11 00 12 00 13 00 14 00 15 00 16 00 17 00 18 00 19 00

109 641 109 289 108 904 108 486 108 036 107 553 107 036 106 487 105 906 105 294

68.129 67.910 67.670 67.410 67.131 66.830 66.510 66.169 65.808 65.427

40 00 41 00 42 00 43 00 44 00 45 00 46 00 47 00 48 00 49 00

85 396 84 137 82 853 81 543 80 208 78 849 77 466 76 058 74 628 73 174

53.063 52.281 51.483 50.669 49.840 48.995 48.136 47.261 46.372 45.469

70 00 71 00 72 00 73 00 74 00 75 00 76 00 77 00 78 00 79 00

38 188 36 353 34 506 32 648 30 781 28 903 27 017 25 123 23 220 21 311

23.729 22.589 21.441 20.287 19.127 17.960 16.788 15.611 14.428 13.242

20 00 21 00 22 00 23 00 24 00 25 00 26 00 27 00 28 00 29 00

104 649 103 972 103 264 102 524 101 754 100 952 100 119 99 257 98 364 97 441

65.026 64.606 64.166 63.706 63.228 62.729 62.212 61.676 61.122 60.548

50 00 51 00 52 00 53 00 54 00 55 00 56 00 57 00 58 00 59 00

71 698 70 200 68 680 67 140 65 578 63 996 62 395 60 774 59 135 57 478

44.552 43.621 42.676 41.719 40.749 39.766 38.771 37.764 36.745 35.716

80 00 81 00 82 00 83 00 84 00 85 00 86 00 87 00 88 00 89 00

19 394 17 472 15 545 13 612 11 675 9 735 7 792 5 846 3 898 1949

12.051 10.857 9.659 8.458 7.255 6.049 4.482 3.632 2.422 1.211

90 00

0

0

From US National Ocean Survey. Tables for a polyconic projection of maps and lengths of terrestrial arcs of meridians and parallels based upon Clarke’s reference spheroid of 1866. 5th edition. Washington 1930, by permission.

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GEOLOGICAL MAPPING

LENGTHS OF DEGREES OF THE MERIDIAN LAT.

METRES

STATUTE MILES

LAT.

METRES

STATUTE MILES

LAT.

METRES

STATUTE MILES

° 0-1 1-2 2-3 3-4 4-5 5-6 6-7 7-8 8-9 9-10

110 567.3 110 568.0 110 569.4 110 571.4 110 574.1 110 577.6 110 581.6 110 586.4 110 591.8 110 597.8

68.703 68.704 68.705 68.706 68.707 68.710 68.712 68.715 68.718 68.722

° 30-31 31-32 32-33 33-34 34-35 35-36 36-37 37-38 38-39 39-40

110 857.0 110 874.4 110 892.1 110 910.1 110 928.3 110 946.9 110 965.6 110 984.5 111 003.7 111 023.0

68.883 68.894 68.905 68.916 68.928 68.939 68.951 68.962 68.974 68.986

° 60-61 61-62 62-63 63-64 64-65 65-66 66-67 67-68 68-69 69-70

111 423.1 111 439.9 111 456.4 111 472.4 111 488.1 111 503.3 111 518.0 111 532.3 111 546.2 111 559.5

69.235 69.246 69.256 69.266 69.275 69.285 69.294 69.303 69.311 69.320

10-11 11-12 12-13 13-14 14-15 15-16 16-17 17-18 18-19 19-20

110 604.5 110 611.9 110 619.8 110 628.4 110 637.6 110 647.5 110 657.8 110 668.8 110 680.4 110 692.4

68.726 68.731 68.736 68.741 68.747 68.753 68.759 68.766 68.773 68.781

40-41 41-42 42-43 43-44 44-45 45-46 46-47 47-48 48-49 49-50

111 042.4 111 061.9 111 081.6 111 101.3 111 121.0 111 140.8 111 160.5 111 180.2 111 199.9 111 219.5

68.998 69.011 69.023 69.035 69.047 69.060 69.072 69.084 69.096 69.108

70-71 71-72 72-73 73-74 74-75 75-76 76-77 77-78 78-79 79-80

111 572.2 111 584.5 111 596.2 111 607.3 111 617.9 111 627.8 111 637.1 111 645.9 111 653.9 111 661.4

69.328 69.335 69.343 69.349 69.356 69.362 69.368 69.373 69.378 69.383

20-21 21-22 22-23 23-24 24-25 25-26 26-27 27-28 28-29 29-30

110 705.1 110 718.2 110 731.8 110 746.0 110 760.6 110 775.6 110 791.1 110 807.0 110 823.3 110 840.0

68.789 68.797 68.805 68.814 68.823 68.833 68.842 68.852 68.862 68.873

50-51 51-52 52-53 53-54 54-55 55-56 56-57 57-58 58-59 59-60

111 239.0 111 258.3 111 277.6 111 296.6 111 315.4 111 334.0 111 352.4 111 370.5 111 388.4 111 405.9

69.121 69.133 69.145 69.156 69.168 69.180 69.191 69.202 69.213 69.224

80-81 81-82 82-83 83-84 84-85 85-86 86-87 87-88 88-89 89-90

111 668.2 111 674.4 111 679.9 111 684.7 111 688.9 111 692.3 111 695.1 111 697.2 111 698.6 111 699.3

69.387 69.391 69.395 69.398 69.400 69.402 69.404 69.405 69.406 69.407

CONVERSION TO THE GEOCENTRIC DATUM OF AUSTRALIA Government maps in Australia from 1998 are based on the Geocentric Datum of Australia (GDA), rather than the Australian Geodetic Datum 1966 (AGD66) or 1984 (AGD84) used in the past. The GDA will ensure that map coordinates are directly compatible with coordinates obtained by global positioning systems, and the move to GDA from the older systems involves a shift of ground coordinates of about 200 metres northeasterly.

172

To convert GDA measurements to the older AGD66 or AGD84 system: Geographicals— add 5.58” to the latitude, and subtract 4.38” from the longitude. UTM grid coordinates— Subtract 184 m from the northing, and subtract 113 m from the easting. More detailed information is available on the web site at: http://www.anzlic.org.au/icsm/icsmmain.htm

Field Geologists’ Manual

GEOLOGICAL MAPPING

5.3.2. CONVERSION OF THE AREA OF A ONE MINUTE SQUARE TO 1 SQUARE KILOMETRES AND SQUARE MILES Lat. 0°00' 15' 30' 45' l°00' 15' 30' 45' 2°00' 15' 30' 45' 3°00' 15' 30' 45' 4°00' 15' 30' 45' 5°00' 15' 30' 45' 6°00' 15' 30' 45' 7°00' 15' 30' 45' 8°00' 15' 30' 45' 9°00' 15' 30' 45' 10°00' 15' 30' 45' 11°00' 15' 30' 45'

Field Geologists’ Manual

km2 3.419 3.419 3.419 3.419 3.418 3.418 3.418 3.417 3.417 3.416 3.416 3.415 3.415 3.414 3.413 3.412 3.411 3.410 3.409 3.408 3.406 3.405 3.403 3.402 3.401 3.399 3.398 3.396 3.394 3.392 3.390 3.388 3.386 3.384 3.382 3.380 3.378 3.376 3.373 3.371 3.368 3.366 3.363 3.360 3.357 3.353 3.350 3.347

sq.mls. 1.320 1.320 1.320 1.320 1.320 1.320 1.320 1.319 1.319 1.319 1.319 1.319 1.318 1.318 1.318 1.317 1.317 1.317 1.316 1.316 1.315 1.315 1.314 1.314 1.313 1.312 1.312 1.311 1.311 1.310 1.309 1.308 1.308 1.307 1.306 1.305 1.304 1.303 1.302 1.301 1.300 1.299 1.298 1.297 1.296 1.295 1.294 1.293

Lat. 12°00 15' 30' 45' 13°00' 15' 30' 45' 14°00' 15' 30' 45' 15°00' 15' 30' 45' 16°00' 15' 30' 45' 17°00 15' 30' 45' 18°00 15' 30' 45' 19°00' 15' 30' 45' 20°00' 15' 30' 45' 21°00' 15' 30' 45' 22°00' 15' 30' 45'

km2 3.344 3.341 3.338 3.335 3.332 3.329 3.325 3.322 3.318 3.315 3.311 3.307 3.304 3.300 3.296 3.292 3.288 3.284 3.280 3.276 3.273 3.267 3.263 3.259 3.254 3.250 3.245 3.240 3.235 3.231 3.226 3.221 3.216 3.211 3.206 3.201 3.196 3.190 3.185 3.180 3.174 3.169 3.163 3.158

sq.mls. 1.291 1.290 1.289 1.288 1.286 1.285 1.284 1.283 1.281 1.280 1.278 1.277 1.276 1.274 1.273 1.271 1.270 1.268 1.266 1.265 1.263 1.262 1.260 1.258 1.256 1.255 1.253 1.251 1.249 1.247 1.246 1.244 1.242 1.240 1.238 1.236 1.234 1.232 1.230 1.228 1.226 1.223 1.221 1.219

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GEOLOGICAL MAPPING

Lat. 23°00 15' 30' 45' 24°00 15' 30' 45' 25°00 15' 30' 45' 26°00 15' 30' 45' 27°00 15' 30' 45' 28°00 15' 30' 45' 29°00 15' 30' 45' 30°00 15' 30' 45' 31°00 15' 30' 45' 32°00 15' 30' 45' 33°00 15' 30' 45'

1

174

km2 3.152 3.146 3.140 3.135 3.129 3.123 3.117 3.111 3.104 3.098 3.092 3.084 3.080 3.074 3.067 3.061 3.054 3.048 3.041 3.035 3.028 3.021 3.014 3.007 3.001 2.993 2.985 2.976 2.971 2.963 2.956 2.948 2.941 2.934 2.926 2.918 2.911 2.903 2.895 2.887 2.879 2.871 2.852 2.854

sq.mls. 1.217 1.215 1.213 1.210 1.208 1.206 1.203 1.201 1.199 1.196 1.194 1.191 1.189 1.187 1.184 1.182 1.180 1.177 1.174 1.172 1.169 1.166 1.163 1.161 1.158 1.155 1.152 1.150 1.147 1.144 1.141 1.139 1.136 1.133 1.130 1.127 1.124 1.121 1.118 1.115 1.112 1.109 1.105 1.102

Lat. 34°00' 15' 30' 45' 35°00' 15' 30' 45' 36°00' 15' 30' 45' 37°00' 15' 30' 45' 38°00' 15' 30' 45' 39°00' 15' 30' 45' 40°00' 15' 30' 45' 41°00' 15' 30' 45' 42°00' 15' 30' 45 43°00' 15' 30' 45' 44°00' 15' 30' 45' 45°00'

km2 2.846 2.838 2.830 2.821 2.813 2.805 2.796 2.787 2.779 2.770 2.761 2.752 2.744 2.735 2.726 2.717 2.708 2.699 2.690 2.691 2.672 2.662 2.653 2.643 2.634 2.624 2.614 2.605 2.595 2.585 2.576 2.566 2.556 2.546 2.536 2.526 2.516 2.506 2.496 2.486 2.476 2.465 2.455 2.444 2.434

sq.mls. 1.099 1.096 1.093 1.090 1.086 1.083 1.080 1.076 1.073 1.070 1.066 1.063 1.060 1.056 1.053 1.049 1.046 1.042 1.039 1.035 1.032 1.028 1.024 1.021 1.017 1.013 1.010 1.006 1.002 0.998 0.994 0.991 0.987 0.983 0.979 0.976 0.972 0.968 0.964 0.960 0.956 0.952 0.948 0.944 0.940

A more precise conversion factor can be calculated from Table 5.3.1.

Field Geologists’ Manual

GEOLOGICAL MAPPING

5.4.1. FRACTIONAL SCALES AND IMPERIAL SYSTEM EQUIVALENTS Fractional Scale of Map

Miles per Inch

Feet per Inch

Chains per Inch

Metres per Inch

Inches per 1000 Feet

1: 1: 1: 1: 1:

200 240 250 400 480

0.003 0.004 0.004 0.006 0.008

16.667 20 20.83 33.33 40

0.252 0.303 0.316 0.505 0.606

5.080 6.096 6.350 10.160 12.192

60 50 48 30 25

1: 1: 1: 1: 1:

500 600 1 000 1 200 1 500

0.008 0.009 0.016 0.019 0.024

41.667 50 83.333 100 125

0.631 0.758 1.263 1.515 1.894

12.700 15.240 25.400 30.480 38.100

24 20 12 10 8

1: 1: 1: 1: 1:

2 000 2 400 2 500 3 000 3 600

0.032 0.038 0.039 0.047 0.057

166.667 200 208.333 250 300

2.525 3.030 3.156 3.788 4.545

50.800 60.960 63.500 76.200 91.440

6 5 4.800 4 3.333

1: 1: 1: 1: 1:

4 000 4 800 5 000 6 000 7 000

0.063 0.076 0.079 0.095 0.110

333.333 400 416.667 500 583.333

5.050 6.061 6.313 7.576 8.838

101.600 121.920 127 152.400 177.800

3 2.500 2.400 2 1.714

1: 1: 1: 1: 1:

7 200 7 920 8 000 8 400 9 000

0.114 0.125 0.126 0.133 0.142

600 660 666.667 700 750

9.091 10 10.100 10.605 11.363

182.880 201.168 203.200 213.360 228.600

1.667 1.515 1.500 1.429 1.333

1: 1: 1: 1: 1:

9 600 10 000 10 800 12 000 13 200

0.152 0.158 0.170 0.189 0.208

800 833.333 900 1 000 1 100

12.121 12.626 13.635 15.152 16.666

243.840 254 274.321 304.801 335.281

1.250 1.200 1.111 1 0.909

1: 1: 1: 1: 1:

14 400 15 000 15 600 15 840 16 000

0.227 0.237 0.246 0.250 0.253

1 200 1 250 1 300 1 320 1 333.333

18.181 18.938 19.695 20 20.202

365.761 381.001 396.241 402.337 406.400

0.833 0.800 0.769 0.758 0.750

1: 1: 1: 1: 1:

16 800 18 000 19 200 20 000 20 400

0.265 0.284 0.303 0.316 0.322

1 400 1 500 1 600 1 666.667 1 700

21.210 22.725 24.240 25.250 25.755

426.721 457.201 487.681 508.002 518.161

0.714 0.667 0.625 0.600 0.588

1: 1: 1: 1: 1:

21 120 21 600 22 800 24 000 25 000

0.333 0.341 0.360 0.379 0.395

1 760 1 800 1 900 2 000 2 083.333

26.664 27.270 28.785 30.303 31.563

536.449 548.641 579.121 609.601 635.001

0.568 0.556 0.526 0.500 0.480

1: 1: 1: 1: 1:

30 000 31 680 40 000 45 000 48 000

0.473 0.500 0.631 0.710 0.758

2 500 2 640 3 333.333 3 750 4 000

37.879 40 50.505 56.818 60.606

762.002 804.674 1 016 1 143 1 219.202

0.400 0.379 0.300 0.267 0.250

1.

l

From Moran, W R, 1958. Handbook for Geologists, (Union Oil Company of California), by permission.

Field Geologists’ Manual

175

GEOLOGICAL MAPPING

Fractional Scale of Map

Miles per Inch

Feet per Inch

Chains per Inch

Metres per Inch

Inches per 1000 Feet

1: 1: 1: 1: 1:

50 000 60 000 62 500 63 360 80 000

0.789 0.947 0.986 1 1.263

4 166.667 5 000 5 208.333 5 280 6 666.667

63.131 75.758 78.914 80 101.010

1 270 1 524 1 587.500 1 609.300 2 032

0.240 0.200 0.192 0.189 0.150

1: 1: 1: 1: 1:

90 000 96 000 100 000 125 000 126 720

1.420 1.515 1.578 1.973 2

7 500 8 000 8 333.333 10 416.667 10 560

113.636 121.212 126.263 157.828 160

2 286 2 438.405 2 540 3 175 3 218.7

0.133 0.125 0.120 0.096 0.095

1: 1: 1: 1: 1:

200 000 250 000 253 440 380 160 500 000

3.157 3.946 4 6 7.891

16 666.667 20 833.333 21 l20 31 680 41 666.667

252.525 315.657 320 480 631.313

5 080 6 350 6 437.4 9 656.1 l2 700

0.060 0.048 0.0473 0.0316 0.024

1: 1: 1: 1:

760 320 1 000 000 5 000 000 10 000 000

12 15.783 78.914 157.828

63 360 83 333.333 416 666.667 833 333.333

960 1 262.626 6 313.131 12 626.262

19 312.2 25 400 l27 000 254 000

0.0158 0.0120 0.002 0.001

Recommended practice

2

The following range of scales for maps and plans is recommended:

It is recommended that the following contour intervals be adopted: 0.5; 1.0; 2; 5; 10; 20; 50; 100; 200 m

Plans: 1:250; 500; 1000; 2000; 2500; 5000; 10 000 Maps: 1:25 000; 50 000; 100 000; 200 000; 250 000; 500 000; 1 000 000

2.

From the Australian Institute of Cartographers, Metric Conversion Subcommittee, Report No. 2.

5.4.2. FRACTIONAL SCALES AND UNIT PLAN AREAS Fractional Scale of Map

1.

176

Inches per Mile

Acres per Square Inch

Square Inches per Acre

l

Square Miles per Square Inch

1: 1: 1: 1: 1:

200 240 250 400 480

316.80 264.00 253.44 158.40 132.00

0.0064 0.0092 0.0100 0.0225 0.0367

156.816 108.900 100.362 39.204 27.225

0.000 010 0.000 014 0.000 015 0.000 040 0.000 057

1: 1: 1: 1: 1:

500 600 1 000 1 200 1 500

126.720 105.600 63.360 52.800 42.240

0.0399 0.0574 0.1594 0.2296 0.3587

25.091 17.424 6.273 4.356 2.788

0.000 06 0.000 09 0.000 25 0.000 36 0.000 56

1: 1: 1: 1: 1:

2 000 2 400 2 500 3 000 3 600

31.680 26.400 25.344 21.120 17.600

0.6377 0.9183 0.9964 1.4348 2.0661

1.568 1.089 1.004 0.697 0.484

0.0010 0.0014 0.0016 0.0022 0.0032

From Moran, W R, 1958. Handbook for Geologists. (Union Oil Company of California), by permission.

Field Geologists’ Manual

GEOLOGICAL MAPPING

Fractional Scale of Map

Inches per Mile

Acres per Square Inch

Square Inches per Acre

Square Miles per Square Inch

1: 1: 1: 1: 1:

4 000 4 800 5 000 6 000 7 000

15.840 13.200 12.672 10.560 9.051

2.5508 3.6731 3.9856 5.7392 7.8117

0.392 0.272 0.251 0.174 0.128

0.0040 0.0057 0.0062 0.0090 0.0110

1: 1: 1: 1: 1:

7 200 7 920 8 000 8 400 9 000

8.800 8 7.920 7.543 7.040

8.2645 10 10.203 11.249 12.913

0.121 0.100 0.098 0.089 0.077

0.0129 0.0156 0.0159 0.0176 0.0202

1: 1: 1: 1: 1:

9 600 10 000 10 800 12 000 13 200

6.600 6.336 5.867 5.280 4.800

14.692 15.942 18.595 22.957 27.778

0.068 0.063 0.054 0.044 0.036

0.0230 0.0249 0.0291 0.0359 0.0434

1: 1: 1: 1: 1:

14 400 15 000 15 600 15 840 16 000

4.400 4.224 4.062 4 3.960

33.058 35.870 38.797 40 40.812

0.030 0.028 0.026 0.025 0.024

0.0516 0.0560 0.0606 0.0625 0.0638

1: 1: 1: 1: 1:

16 800 18 000 19 200 20 000 20 400

3.771 3.520 3.300 3.168 3.106

44.995 51.653 58.770 63.769 66.345

0.022 0.019 0.017 0.016 0.015

0.0703 0.0807 0.0918 0.0996 0.1037

1: 1: 1: 1: 1:

21 120 21 600 22 800 24 000 25 000

3 2.933 2.779 2.640 2.534

71.111 74.380 82.874 91.827 99.639

0.014 0.013 0.012 0.011 0.010

0.1111 0.1162 0.1295 0.1435 0.1557

1: 1: 1: 1: 1:

30 000 31 680 40 000 45 000 48 000

2.112 2 1.584 1.408 1.320

143.480 160 255.076 322.830 367.309

0.007 0.006 0.004 0.003 1 0.002 7

0.2242 0.2500 0.3985 0.5044 0.5739

1: 1: 1: 1: 1:

50 000 60 000 62 500 63 360 80 000

1.267 1.056 1.014 1 0.792

398.556 573.921 622.744 640 1 020.304

0.002 5 0.001 7 0.001 6 0.001 6 0.000 9

0.6227 0.8967 0.9730 1 1.5942

1: 1: 1: 1: 1:

90 000 96 000 100 000 125 000 126 720

0.704 0.660 0.634 0.507 0.500

1 291.322 1 469.240 1 594.225 2 490.976 2 560

0.000 77 0.000 68 0.000 627 0.000 401 0.000 390

2.0173 2.2957 2.4909 3.8922 4

1: 1: 1: 1: 1:

200 000 250 000 253 440 380 160 500 000

0.317 0.253 0.250 0.167 0.127

6 376.900 9 963.906 10 240 23 040 39 855.626

1: 1: 1:

760 320 1 000 000 10 000 000

Field Geologists’ Manual

0.083 0.063 0.0063

92 160 159 422.507 15 942 250.70

0.000 157 0.000 100 0.000 098 0.000 043 4 0.000 025 0 0.000 010 9 0.000 006 3 0.000 000 063

9.9639 15.5686 16 36 62.2744 144 249.0976 24 909.76

177

GEOLOGICAL MAPPING

5.4.3. NOMOGRAM FOR ESTIMATING AREA

1.

178

1

From Moran, W R, 1958. Handbook for Geologists, (Union Oil Company of California). By permission with amendments.

Field Geologists’ Manual

GEOLOGICAL MAPPING

5.4.4. NOMOGRAM FOR ESTIMATING TRUE WIDTH

1.

1

From Palmer, H S, 1918. New graphic method for determining the depth and thickness of strata and the projection of dip. USGS Prof. Paper 120-G, pp 123-128, by permission.

Field Geologists’ Manual

179

GEOLOGICAL MAPPING

5.5. GEOLOGICAL TIME SCALE

1

PLANKTIC FORAMINIFERAL ZONATIONS NEW ZEALAND

Blow 1979; Kennett & Srinivasan 1983

Berggren et al. 1994a,b

Stage

Symbol

Low-latitude

Series

Chrons

Period / Epoch

European Stage

ZONATIONS

Polarity

Geochronometric Scale (Ma)

QUATERNARY STAGES

Haweran

Wq

Castlecliffian

Wc

Holocene

0.1

Late

0

N.23

0.2 0.3

0.8 0.9 1.0

N.22

1.1

1.5 1.6

a

Matuyama

CM

C1r

1.4

Early

1.2

Calabrian

J

1.3

Wanganui

0.7

N22

Pleistocene

0.6

Middle

Brunhes

0.5

C1

0.4

b

Nukumaruan Wn

1.7

2.0

1.

180

Pia.

Late

O

Plio.

1.9

C2

1.8

PL6 N.21

20/A/233

Prepared by the Australian Geological Survey Organisation, Canberra.

Field Geologists’ Manual

GEOLOGICAL MAPPING

C3

Gilbert

Zanclean

9 10

CN14 CN13

C3Br

C4 C4r C4A C4Ar

Tortonian

C5

11

a

CN12

a

NN14 NN13

CN11

NN12

CN10

a b a b

NN17 NN15

NN16

PT1

b

NN11

CN9

NN10 NN9 NN8

CN8 ba CN7 ba CN6

PL6 PL5

14

C5AC C5AD

C5AB

15

C5B

Langhian

16

PL2 b

PL1

18 19 20 21

C6A C6AA C6AAr

24 25

NN3

C6

C10

30

C11

31 32

Late

Oligocene

C9

29

C12

Chattian

Tf 2 Balcombian

Tf 1

M2

Globigerina woodi connecta

Longfordian

b a

Rupelian

Priabonian

Globigerina euapertura

a a

Te 1-4

b

NP23

NP19/20

P20

CP18

CP16

CP15

c b a b

NP18

a

NP17

b

Td

P19

Globigerina angiporoides

P18

Globigerina brevis

Tc

Globigerina linaperta

Tb

P17 P16

C18

Willungan

CP14

41

NP16

NP15

CP12

C22

NP13

CP11

P9

NP12

CP10

P7

C24

NP10

b

CP8

b

NP9

56

Thanetian

60 61 C27 C28

Late

Selandian

Waiauan

Sw

Lillburnian

Sl

Clifdenian

Sc

Altonian

Pl

Otaian

Po

Waitakian

Lw

Duntroonian

Ld

Whaingaroan

Lwh

Runangan

Ar

Kaiatan

Ak

Bortonian

Ab

Porangan

Dp

Heretaungan

Dh

Danian

Late

C29

K

P6

NP7

CP6 CP5

NP5

CP4

NP4

CP3

Ta2

a Pseudohastigerina wilcoxensis

P5

CP7

NP6

NP3 NP2 NP1

64

C30

NP8

a

a

Morozovella crater

b

Mangaorapan

Dm

Waipawan

Dw

Teurian

Dt

c b P4

a

P3

Wangerripian

Globigerina triloculinoides

b a

Ta1

P2

Early

C26

Paleocene

C25

58

65

CP9

Dannevirke

Early

NP11

55

63

Tt

P8

Ypresian

53

62

Tongaporutuan

b a

C23 52

57

Tk

Acarinina primitiva

P10

NP14

51

59

Johannian

b a

C21

49

54

Wo

Kapitean

Ta3

P11

CP13

47

50

Globigerinatheka index

P12

c

Lutetian

46

48

Wp

Opoitian

P13

a

Middle

Eocene

C19

C20

Wm

Waipipian

Aldingan

Testacarinata inconspicua

P14

40

45

Mangapanian

P15

Bartonian

39

44

Wn

Globoquadrina dehiscens

C17 38

43

Nukumaruan

Te5

Globigerina woodi woodi

P22

b

37

42

Series

Batesfordian

Globigerinoides trilobus

CP19

NP21 Late

C16

Praeorbulina glomerosa curva

M3

b

CP17

C15

a

M1

NP22

36

Bairnsdalian

Symbol

a

C13

35

Gr. mayeri Orbulina suturalis

c b

M4

P21

33 34

b

Mitchellian

a

c

NP24

Early

28

Tf 3

miotumida

?

M11

M8 M7

CN2

NP25

C8

27

Cheltenhamian

Stage

a

C7 C7A

26

M10

M9

CN4

NN1

Kalimnan

M6

CN1

C6B C6C

Globorotalia

a

NN2

Aquitanian

Tg

b

M5

Burdigalian

C5E

Werrikooian Yatalan

Globorotalia conomiozea

M14

a

NN6

NN4

22 23

CN5

NN5

Th

Globorotalia puncticulata

M12

b

CN3

C5D

a

M13

C5C

Early

17

Serravallian

Globorotalia inflata

a

NN7 Middle

13

C5Ar C5AA

Miocene

C5A

Globorotalia truncatulinoides

PL4 PL3

C5r 12

a

a

d

NN18

C3B

Late

8

NN19

Messinian

C3A 7

NN20

Wanganui

Piacenzian

6

b

b

Calabrian

Taranaki

5

CN15

Southern Mid-latitude

Southland

Gauss

Berggren et al., 1994a, b

Landon

C2A

4

Low-latitude Okada & Bukry, 1980

New Zealand

South Eastern

Australian East Indian Local Stages Letter Stage

Arnold

C2r

M

INTERNATIONAL FORAMINIFERAL ZONES

Pareora

Brunhes H Matuyama

Standard

NN21

L

Late Early

C2

Pliocene Ple.

3

C1r

INTERNATIONAL NANNOFOSSIL ZONES Martini, 1971

Berggren et al., 1994a, b

C1 1 2

Epoch

Chrons

European Stage

Early

0

Polarity

Geochronometric Scale (Ma)

TERTIARY STAGES

Maastrichtian

Field Geologists’ Manual

CP2 CP1

c

b a

P1 b

Globigerina pauciloculata

a P α & PO

Haumurian

20/A/232

181

GEOLOGICAL MAPPING

CRETACEOUS STAGES

182

Field Geologists’ Manual

GEOLOGICAL MAPPING

JURASSIC STAGES

Field Geologists’ Manual

183

GEOLOGICAL MAPPING

TRIASSIC STAGES

184

Field Geologists’ Manual

GEOLOGICAL MAPPING

SERIES

AGE (Ma)

PERMIAN STAGES

N O RT H STAGES

S O UT H CHINA

LOPINGIAN

251

?

LOPINGIAN DZHULFIAN

TATARIAN

CAPITANIAN

MIDIAN

CAPITANIAN

MAOKOUAN

KAZANIAN MURGABIAN

WORDIAN

ROADIAN

UFIMIAN

WORDIAN

ROADIAN

270

KUNGURIAN

CHIHSIAN

BOLORIAN

LEONARDIAN

AKTASTINIAN

ARTINSKIAN

SAKMARIAN

TASTUBIAN

SAKMARIAN

ASSELIAN

298

Field Geologists’ Manual

ASSELIAN

20/A/237

185

GEOLOGICAL MAPPING

CARBONIFEROUS STAGES

186

Field Geologists’ Manual

GEOLOGICAL MAPPING

DEVONIAN STAGES

Field Geologists’ Manual

187

GEOLOGICAL MAPPING

SILURIAN STAGES

Ma

410

415

nilssoni

420

425

celloni

430

cyphus

435

188

Field Geologists’ Manual

GEOLOGICAL MAPPING

ORDOVICIAN STAGES

Field Geologists’ Manual

189

GEOLOGICAL MAPPING

CAMBRIAN STAGES

190

Field Geologists’ Manual

GEOLOGICAL MAPPING

COMPARATIVE PRECAMBRIAN SUBDIVISIONS IUGS

(Subcommission on Precambrian Stratigraphy)

AGE

EON

ERA

PERIOD

OLD AUSTRALIAN SUBDIVISION Dunn et al.,1966

INTERNATIONAL COMPARISONS NORTH AMERICA

Plumb, 1990 Preiss, in press

CANADA

U.S.S.R.

CHINA

STH AFRICA

"Neoproterozoic III"

Statherian 1800

PALAEOPROTEROZOIC

Orosirian 2050

Rhyacian 2300

CARPENTARIAN 1800

EARLY PROTEROZ.

1400

CARPENTARIAN 1800

2300

Siderian

2400 2500

2500 Ma

2500

2500

3500

PALAEOARCHAEAN

1400

Paleohel 1750

Neoaph

1860

Mesoapheb. 2250

Jixian System

Namibian 900

1050

Middle 1350

Lower 1600

1650

Changcheng System

Lower Proterozoic

2050

Lower Proterozoic

Vaalian

Paleoaph 2500

ARCHAEAN

Mogolian

1850

2500

2500 2600

Randian

2800

ARCHAEAN

ARCHAEAN*

2800 Ma

MESOARCHAEAN 3200 Ma

Neohel

1000

NULLAGINIAN

NEOARCHAEAN

3000

1600

Early Proterozoic (X)

**

(Nullaginian)

Middle Proterozoic (Y)

Qingbaikou

1000

680 700

Upper

PROTEROZOIC

1600 Ma

1400

800

ARCHAEAN (W)

ARCHAEAN

ARCHAEAN

ARCHAEAN

ARCHAEAN

1400

Calymmian

PROTEROZOIC

Ectasian

**

Aphebian

2000

MESOPROTEROZOIC

1200

PROTEROZOIC

PROTEROZOIC +

Stenian

1500

900

ADELAIDEAN

Vendian Kudash

Sinian Sys.

700

RIPHEAN

Tonian

1000 Ma

Neohad

Paleohad

PROTEROZOIC

~830

850

PROTEROZOIC

1000

(Z) Late Proterozoic

ADELAIDEAN

Cryogenian

Hadrynian

545 Ma 650

NEOPROTEROZOIC

Helikian

500

PROTEROZOIC

(Ma)

3000

Swazian

3600 Ma

EOARCHAEAN 4000 +

Subdivision of the Proterozoic by the Subcommission on Precambrian Stratigraphy (SPS) has been formalised by the IUGS, and is now in widespread use (Plumb, K.A., Episodes, 14, 139-140).

* Subdivision of the Archaean is provisional only. At the time of writing (March 1999) the recommendations shown for the Archaean have been accepted by formal postal ballot of SPS and a formal proposal is in preparation for ratification and formalising by the IUGS.

Dunn, Plumb, & Roberts, 1966, J. Geol. Soc. Aust. , 13:593-608 Plumb, 1990, In Geology of the Mineral Deposits of Australia and Papua New Guinea (Ed. F.E. Hughes), pp27-32 (AusIMM, Melbourne). Preiss, in press, Precambrian Research. The old scale is included mainly for comparative purposes; it is recommended that it be used only in reference to the successions from which it was named. Note that it is a chronostratigraphic subdivision, and is conceptually different from the purely chronometric IUGS scale. (No units are yet defined to fill the time gaps shown by ** above).

Decade of North American Geology Series. Spec. Publs Geol. Soc Am. Throughout USA, Canada & Mexico. W,X,Y,Z: old USGS terms for same units.

Okulitch, 1988. Geol. Surv. Can. Pap. , 87-23. Okulitch also incorporates the adjacent DNAG 3-fold subdivision of the Proterozoic, as an alternative.

Keller, 1979. Sun & Lu, 1985. Precambrian Res., Geol. Mag., 116: 419-504. 28: 137-162. Wide opinion that base Changcheng is now 1850 Ma (cf. Sun & Lu). ChangchengJixian boundary usually 1400 Ma: prefer Sun & Lu.

Decision by South African Committee for Stratigraphy, August 1988 (unpublished). Modifies SACS, 1980. Handb. Geol. Surv. S. Afr.

Provided by I. Sweet (AGSO) and K.A.Plumb (Consultant)

REFERENCES Berggren W A, Kent, D V, Swisher, C C and Aubry, M P, 1995. A revised Cenozoic geochronology and chronostratigraphy, in Geochronology, Time Scales and Global Stratigraphic Correlation, SEPM Special Publication 54 (Eds: Berggren W A, Kent, D V, Aubry M P and Hardenbol, J), pp 129-212. (This was originally received as two separate preprints which were to be published in 1994, however, they were amalgamated into one paper and published a year later). Blow, W H, 1979. The Cainozoic Globigerinida; a study of the morphology, taxonomy, evolutionary relationships and the stratigraphical distribution of some Globigerinida (mainly Globigerinacea), (E J Brill: Leiden). Kennett, J P and Srinivasan, M S, 1983. Neogene Planktonic Foraminifera: a Phylogenetic Atlas, (Hutchinson Ross: Stroudsburg).

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Martini, E, 1971. Standard Tertiary and Quaternary calcareous nannoplankton zonation (Ed: Farinacci, A), pp 739-785 in Proceedings of the Second Planktonic Conference, Roma (Edizioni Tecnoscienza: Roma). Nowlan, G S, 1993. The ancient biosphere, in Geoscience Canada, 20(3), pp 113-122. Okada, H and Bukry, D, 1980. Supplementary modification and introduction of code numbers to the low-latitude coccolith biostratigraphic zonation, in Marine Micropaleontology, 5: 321-325. Strusz, D L, 1989. Australian Phanerozoic Timescales: 3. Silurian - biostratigraphic chart and explanatory notes. Bureau of Mineral Resources, Geology and Geophysics, Record 1989/33.

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5.6.1. STANDARD MAPPING SYMBOLS – AGSO SYSTEM 1 INTRODUCTION A standard series of symbols is used on geological maps published by government agencies in Australia. The symbols are presented in Symbols Used on Geological Maps, available from the Australian Geological Survey Organisation (AGSO) at GPO Box 378, Canberra, ACT, AUSTRALIA 2601 or by phone at 61 2 6249 9111. Only those symbols that may be required for field drafting are presented here. AGSO has digital versions of the symbols, identified as AGSOSYM, suitable for use in computer applications such as MicroStation and Arc/Info. These are available by application to the AGSO Sales Centre. Symbol fonts suitable for use in PC-based applications

such as Maplnfo, ArcView, etc are being prepared. The symbols are also available from AGSO as a wall chart. Standard symbols to show the age of rock units and standard colours for geological maps are provided in Section 5.6.3. of this manual. Some of the patterns used to show rock type, shown at the end of this section, are also available from AGSO in digital format, identified as PUBPAT.CEL (MicroStation Cell Library). Line thickness is generally 0.15 mm for geological boundaries, and for bedding, foliation, joint, cleavage and lineation symbols (Sections 2, 6, 7, 8, 9, 10 and 11 herein), 0.2 mm for dykes and veins and mining symbols (Sections 4 and 14), 0.3 mm for fold axes (Section 5), and 0.4 mm for fault traces (Section 3).

Arrows and arrowheads The style of arrow and arrowhead for structural symbols indicates a particular type of observation: Bedding (including facing, direction of sedimentation, prevailing dip of folded strata, and plunge). Direction of movement. Metamorphic foliation, other than cleavage (cleavage follows past usage). Primary banding, other than bedding (eg flow banding). Lineation of all kinds, including trace of a plane on another plane. Specific types of lineation. Arrows with both open and closed triangles are used as part of fold symbols. Fold, facing not known (eg 5.11.1). Vertical fold (eg 5.8.1). Other styles of arrows available for miscellaneous purposes are but the compiler should ensure that the styles adopted are distinctive; this is most important when draftsmen are not available for compilation. Combined symbols Where more than one structural element is observed at a locality, symbols are usually combined on the map. Examples appear under Faults, Folds, Bedding, Metamorphic Foliation, Cleavage, and Lineation. To avoid lengthy and complicated descriptions, combined structural symbols may be shown separately in the symbols reference and the following note added: 'Some structural elements observed at a single locality are combined on the map' For ease of drafting combined symbols should either be standardised so they can be reproduced on stripping film, or be formed by combining standard basic symbols. Not measured or prevailing dips and plunges Where dips or plunges are measured the value is shown with the symbol. Where not measured, or where the symbol shows the prevailing dip or plunge, no value is shown and 'not measured' or 'prevailing' is added to the symbol description if desired. eg

Strike and dip of strata, dip not measured or Prevailing strike and dip of strata or Strike and dip of strata

To avoid repetition of 'not measured' or 'prevailing' dip and plunge descriptions in a reference with numerous structural symbols, insert the following note after the last structural symbol:

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'Dips and plunges without values are not measured, or prevailing’ A combined dip and plunge symbol will commonly show the plunge value, but if it does not, the plunge value can be measured from the geometry of the symbol. eg

Strike and dip of strata and plunge of bedding-cleavage intersection or Strike and dip of strata and plunge of bedding-cleavage intersection

Facing or younging not known Double lines in structural symbols at least in large-scale maps, indicate that the facing or younging is not known (eg 6.2.11. 5.14.9 to 5.14.12). On small-scale maps double lined symbols present difficulties in drafting and reproduction and should be avoided. Classification of geological boundaries, faults, and fold axial surface traces Classification is governed by: ! Geological certainty; and ! Planimetric accuracy. For example, boundaries are established or inferred. Established boundaries may be accurate (located within the thickness of the line drawn), approximate, or concealed; inferred boundaries are approximate and may be concealed (deduced, not observed). A concealed, but not inferred, boundary is one established by sub-surface exploration or is an established boundary beneath cover. For cartographic convenience, question marks may be omitted from inferred boundaries and faults portrayed in geological cross-sections, If this is done it should be noted above the cross-section.

Units of measurement Care should be taken to use legal units of measurement on maps and to avoid the use of non-legal units as far as possible. Information on the standing of units may be obtained from publications of the Metric Conversion Board.

Other sources of standard symbols ! Standard symbols for age of rock units ! Standard colours or geological ages

‘Australia Standard Colour Scheme and Stratigraphic Symbols for Geological Maps’, Section 5,6.3.

! Screens and patterns (in black and white) showing the range of variations that can be achieved by use of screens and overprinting patterns available to BMR, at the end of this section. The International Standards Organisation (ISO) has compiled International Standard ISO/DIS 710 which covers graphical symbols for use on detailed maps, plans, and geological cross-sections (including letter symbols for minerals and rocks). Some of the symbols adopted in this booklet are at variance with ISO symbols. Australian Standards Association, Standard A. SK183 covers lithological symbols for coal seams, some associated rocks, and letter symbols for some minerals and rocks. State and Territory authorities may also be consulted for local standards.

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PATTERNS FOR GEOLOGICAL MAPS IN BLACK AND WHITE Patterns can be differentiated by varying weight and density of stipple, weight and spacing of lines, etc. Line patterns wherever possible should be oriented with the trend of the rock denoted.

Sedimentary rocks Conglomerate

Sandstone, quartzite, arkose, etc.

Sedimentary rocks (cont.) Shale, siltstone, claystone, etc. Sandy

Sandy conglomerate, pebbly sandstone, etc.

Normal

Chert Bedded

Limestone and dolomite

Sandy limestone

Coal, carbonaceous shale, etc. Black coal unspecified

Broken coal

Massive

Coal with shale bands

Cannel coal

Carbonaceous shale

Shale with coal bands

Cannel shale

Brown coal

Oil shale

Grades of Black coal Calorific value−B.T.U. >11 500 11 500-10 000 <10 000 Ash content (used when calorific is not available) < 15% 15% < 20% 20% and above

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Suitable for thin beds, coal seams, etc.

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Metamorphic rocks Slate, phyllite, schist, etc

Igneous rocks

High grade metamorphic: schist, gneiss, etc

Sandy slate or interbedded sediments

Acid and intermediate plutonic rocks

Basic plutonic or hypabyssal rocks

Hypabyssal rocks

Bedded lavas

Volcanic rocks

Suitable for massive rocks (hornfels, etc) or for areas in which open pattern required

Miscellaneous Tuff or tuffaceous sandstones

Bedded tuff, tuffaceous shale or slate

Brecciated rock or scree

Alluvium

Suitable for small areas denoting gossan, ore, etc, or for picking out small outcrops Breccia

Soil cover

In special cases a letter pattern may be useful to denote lithological changes within a unit Hornblende granite

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Biotite granite

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5.6.2. GRAPHIC REPRESENTATION OF COAL SEAMS

Symbol No:

Symbol Shading system

Line system

Abb.

Description and remarks

Symbol No:

1

Symbol Shading system

Line system

Abb.

Description and remarks

1

U

COAL− undifferentiated

7

D

COAL− dull (up to and including 1 per cent bright)

2

B

COAL− bright (greater than 90 per cent bright)

8

Dch

COAL− dull conchoidal (Canneloid)

Bd

COAL− bright with dull bands (over 60 and up to, including 90 per cent bright)

9

F

DB

COAL− interbanded dull and bright (over 40 and up to, including 60 per cent bright)

10

W

COAL− weathered

Db

COAL− mainly dull with frequent bright bands (over 10 and up to, including 40 per cent bright)

11

X

COAL− heat altered

Dmb

COAL− dull with minor bright bands (over 1 and up to, including 10 per cent bright)

12

R

NON-COAL− undifferentiated

3

4

5

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Description

13

Cr

COAL− interlayed with non-coal

14

Rc

NON-COAL− interlayed with coal

15

Sc

STONY COAL

16

Sh

SHALE

17

Ms

MUDSTONE

18

Ss

SANDSTONE

19

Cgl

CONGLOMERATE

20

Tf

TUFF

21

Ig

IGNEOUS ROCK

Symbol

EXAMPLE OF SYMBOLS AND ABBREVIATIONS

MINERAL ABBREVIATIONS

1.

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From Anon, 1970. Symbols for the Graphical Representation of Coal Seams, Aust Standard K 183—1970, p 8. (Standards Assocn Aust: Sydney), by permission.

Mineral Calcite Carbonate Iron Pyrite Siderite Sulphur

Abbreviation Calc CO3 Fe Py Sid S

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5.7 ABRIDGED GUIDE TO LITHOSTRATIGRAPHIC NOMENCLATURE IN 1 AUSTRALIA

(i)

Lithostratigraphy— that element of stratigraphy which is concerned with the organisation of strata into units based on their lithologic character.

(ii) Biostratigraphy— that element of stratigraphy which is concerned with the organisation of strata into units based on their fossil content. (iii) Chronostratigraphy— that element of stratigraphy which is concerned with the

SERIES III

N

Sequence 4 Sequence 3

3500 5100

3200

Zone P

Biozone z Biozone x

Biozone y

R

Sequences

Sequence 2

Series and Stages

Sequence 1

Barren

N

Biozone d Biozone c Biozone b Biozone a

Seismic Vel. (m/Sec.)

Stage K

Magnetic Reversals

Zone R

Barren

Member .

Member Formation C

Form. B

Spores and Pollen Zone S

RO ST SEQU N RA UN OSTR TIG ENCE I T S AT R . UN APH ITS IC

SERIES IV

Mollusks

Zone Q

Foraminifera

.

Formations Members

GEOPHYSICAL UNITS

3000

BIOSTRATIGRAPHIC UNITS

4200

HO U N S T RA I T S T.

Formation D

(b) Categories of stratigraphic classification

CH

LIT

Formation A

It is possible to classify stratified rocks according to any of their properties: lithology, fossil content, magnetic polarity, electrical properties, seismic response, chemical or mineralogical composition, sequence boundaries, geochemistry, and many others. A different set of units is needed for each property (Figure 1).

Stage J

Provided by H R E Staines and revised by A T Brakel, 1999.

Barren

1.

(a) General

Stage G

The Australian Code of Stratigraphic Nomenclature (ACSN) (1973) was replaced by the International Stratigraphic Guide (ISG) (Hedberg, 1976) in 1978. An abridged version of the ISG, interspersed with notes relating to Australian practice, was published as the Field Geologist’s Guide to Stratigraphic Nomenclature in Australia (FGG) (Staines, 1985). The second edition of the ISG (Salvador, 1994) has now been adopted as the official guide by the Australian Stratigraphic Names Committee, except for adaptations to Australian conditions as indicated by the Notes in Staines (1985) and subsequent decisions of the Committee. To provide a concise reference in the present volume the Field Geologist’s Guide has been further extensively abridged. The complete FGG and/or USG should be consulted by workers wishing to establish new lithostratigraphic units. The FGG concerns itself only with lithostratigraphic nomenclature. In matters of biostratigraphic or chronostratigraphic nomenclature, the ISG should be consulted.

2. PRINCIPLES OF STRATIGRAPHIC CLASSIFICATION

Stage F

1. INTRODUCTION

FIG 1 - Illustration of differences in position in a stratigraphic section of division points for different properties or attributes of strata.

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organisation of strata into units based on their age relations. (iv) Sequence stratigraphy— that element of stratigraphy which is concerned with the organisation of strata into units based on the unconformities and correlative conformities (sequence boundaries) that contain them. (c) Distinguishing terminologies for each category For lithostratigraphy and chronostratigraphy the numerous terms represent different hierarchical ranks; for biostratigraphic units they result from the recognition of various kinds of biozones (see Table 1). (d) Chronostratigraphic and geochronologic units

‘Early’, ‘Middle’ and ‘Late’ should be used for time (geochronologic) terms and ‘Lower’, Middle’, and ‘Upper’ should be used for time-rock (chronostratigraphic) terms. Ideally, all of these terms should be formalised by capitalisation of the initial letter. Because of the difficulties of global correlation it is not possible to unequivocally apply formal chronostratigraphic terms to Australian sequences, and therefore informal usage, ie with lower case initial letters, is allowable. However, care should be taken to avoid inadvertent formalisation, eg in all-upper-case typing and in written reporting of an oral presentation.

Note 2. Abbreviation of ‘lower’ The abbreviation ‘L’ or ‘l’ for ‘lower’ should not be used because the letter can also stand for ‘late’.

3. DEFINITIONS AND PROCEDURES

Each interval of stratified rocks represents a certain interval of geologic time. Accordingly, each chronostratigraphic unit (interval of rock strata) has a corresponding geochronologic unit (interval of geologic time) (See Table 1).

(a) Definitions (i)

Note 1. Geochronologic and chronostratigraphic terms

Stratigraphy is literally the descriptive science of rock strata, and covers all classes of rocks—igneous, metamorphic, and sedimentary, consolidated and unconsolidated.

TABLE 1 Summary of categories and unit terms in stratigraphic classification. (If additional ranks are needed, prefixes Sub and Super may be used with some unit-terms when appropriate. Although restraint is recommended to avoid complicating the nomenclature unnecessarily. Stratigraphic categories

Principal stratigraphic unit-terms

Lithostratigraphic

Group Formation Member Bed(s)

Biostratigraphic

Biozones Assemblage zones Range zones (various kinds) Acme-zones Interval zones Other kinds of biozones

Chronostratigraphic

Eonothem Erathem System Series Stage Chronozone

Sequence stratigraphic

Sequence

Other stratigraphic categories (mineralogic, environmental, seismic, magnetic, etc)

Zone (with appropriate prefix)

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Equivalent geochronologic units

Eon Era Period Epoch Age Chron

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(ii) Stratum. A geologic stratum is a layer of rock characterised by certain unifying characters, properties, or attributes that distinguish if from adjacent layers. (iii) Stratigraphic classification is the systematic organisation of the Earth’s rock strata into units with reference to any of the characters, properties, or attributes that rocks may possess. (iv) A stratigraphic unit is a stratum or assemblage of adjacent strata recognised as a distinct entity in the classification of the Earth’s rock sequence. (v) Stratigraphic terminology deals with the unit terms used in stratigraphic classification, such as formation, stage, biozone. It can be either formal or informal.

Note 3. Formal and informal lithostratigraphic units The ISG distinguishes between formal and informal lithostratigraphic units, but most of the examples of informal units constitute such casual usage that they do not fall within the definition of ‘stratigraphic nomenclature’. To avoid confusion authors are strongly urged not to establish informal units wit the binomial form of a geographic name followed by an uncapitalised lithological term. (vi) Stratigraphic nomenclature deals with the proper names given to specific stratigraphic units. (vii) A stratotype is the type representative of a named stratigraphic unit or of a stratigraphic boundary. (b) Procedures for establishment and description of stratigraphic units (See Sections 5 and 6) (c) Special requirements for establishment and description of stratigraphic units The same general rules for outcrop sections apply to subsurface units.

Note 4. Subsurface units It is desirable that formal names not be given to formations which are identified in only one borehole. At least two borehole sections are required if surface sections are not available.

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(d) Publication Establishment of a formal stratigraphic unit requires that an adequate description of the unit be published in a recognised scientific medium, such as a regularly issued scientific journal.

Note 5. Publications The following are not regarded as publications for stratigraphic nomenclature purposes: (i)

Any source which may only be quoted from by permission of the issuing body.

(ii) Preliminary edition maps of BMR, AGSO, or State/Territory Geological Surveys. (iii) Reports and abstracts of addresses delivered to scientific meetings. (iv) GSA Specialist Group newsletters, and similar issues. (The Australian Geologist is regarded as a publication). Quotation in a publication, of a previously unpublished name renders the name ‘published’, even if quotation marks are used.

Note 6. Recording of published names of units which are adequately described or defined The Central Register of Stratigraphic Names records all names that consist of a geographic name and a lithological or stratigraphic term (formation, group, member) and are published in a recognised scientific or technical journal, whether the name of the unit is valid or not. (e) Priority Priority in publication of a properly proposed, named, and defined unit should be respected. (f) Synonymy Before attempting to establish a new formal stratigraphic unit, authors should refer to national, state or territory records of stratigraphic names to determine whether a name has been previously used. (g) Revision or redefinition of previously established units Revision or redefinition of an adequately established unit without changing its name requires as much justification, and the same kind of information, as for establishing a new unit. (h) Subdivision When a unit is divided into two or more units, the original name should not be employed for any of the subdivisions. However, it may be retained in a higher category which includes the new units.

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(i) Change in rank Change in rank of a stratigraphic unit does not require redefinition of the unit or its boundaries or alteration of its proper name. (j) Reduction in number of names through correlation If correlation has established the equivalence of two named stratigraphic units, the later name should be replaced by the earlier. (k) Uncertainty in assignment

Note 7. Hyphenation of two unit names to describe strata that cannot be certainly assigned to either This practice has not been followed in Australia in the past and it is strongly recommended that it should be avoided. (l) Abandoned names A name for a stratigraphic unit, once applied and then abandoned, preferable should not be revived except in its original sense.

Note 8a. Re-use of abandoned names Because of the shortage of available geographic names in some areas, re-use of abandoned names may be approved in some limited circumstances, provided the name is used in a different geological province, and there is no possibility of confused, (Brakel, 1989). Validly defined abandoned names may be re-used if they have been absent from the literature for 25 years, with the following exceptions: (i)

in the case of poorly known names that now disused because of hierarchical changes, the absence from the literature must be 50 years before they can be re-used;

(ii) widely known names that are now disused because of hierarchical changes or because the units have subsequently been found to be geologically invalid may not be re-used. For abandoned names that were published invalidly for some reason, the situation is more complication. The National Convener of the Stratigraphic Names Committee, or the local State/Territory Subcommittee, can give advice on whether or not a particular abandoned name can be re-used. (m) Duplication of names Duplication of names should be avoided. A name previously applied to any unit should be later be

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applied to another unless geographic separation precludes confusion.

Note 8b. Duplication of names Because of the shortage of available geographic names in some areas, some duplication of names may be acceptable. The same geographic name should not be used for two units:(i)

in the same State or Territory, or in contiguous States or Territories; or

(ii) of approximately the same age; or (iii) of similar rock types. Advice will be given on request by the Convener of the Stratigraphic Nomenclature Committee whether duplication of a particular name is acceptable.

4. STRATOTYPES A stratotype (type section) is the original or subsequently designated type of a named stratigraphic unit or of a stratigraphic boundary, identified as a specific interval or a specific point in a specific sequence of rock strata, and constituting the standard for the definition and recognition of the stratigraphic unit or boundary. A complete exposure of all strata in the unit from bottom to top and throughout its entire lateral extent would be the ideal stratotype. However, because it is impossible to find or establish such a comprehensive stratotype, reliance is usually placed on a single section, as complete and well exposed as possible. The description of a stratotype should be both geographic and geologic. The geographic description should enable anyone to find the stratotype easily in the field. The geologic description should cover thickness, lithology, papaeontology, mineralogy, structure, geomorphic expression and other geologic features of the type section. The boundaries and relations with adjacent units particularly should be described in detail, and reasons for choice of boundaries should be given. A unit-stratotype is the type section of strata serving as the standard for the definition and recognition of a stratigraphic unit. The upper and lower limits of a unit-stratotype are its boundary-stratotypes (see Figure 2a). A boundary-stratotype is a specific point in a specific sequence or rock strata that serves as the standard for definition and recognition of a stratigraphic boundary (see Figure 2b). A composite-stratotype is a unit-stratotype formed by the combination of several specified type intervals of strata known as component-stratotypes. The type locality of a stratigraphic unit, boundary, or other feature is the specific geographic locality in

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FIG 2a - unit-stratotype and boundary stratotypes for a lithostratigraphic unit (Formation B). FIG 2b - boundary- stratotypes for chronostratigraphic units (Upper boundary of stage A is lower boundary of stage B).

degree of overall lithologic homogeneity. Lithostratigraphic units are recognised and defined by observable physical features and not by inferred geologic history or mode of genesis. Only major lithologic features readily recognisable in the field should serve as the basis for lithologic units.

which its stratotype is situated, or lacking a designated stratotype, the locality where is was originally defined or named. The type area (or type region) is the geographic territory surrounding the type locality.

5. LITHOSTRATIGRAPHIC UNITS (a) Purpose of lithostratigraphic classification The purpose of lithostratigraphic classification is to organise systematically rock strata of the Earth into Named units that will represent the principal variations of these rocks in lithologic character. (b) Definitions (i)

Lithostratigraphy is the element of stratigraphy that deals with the lithology of strata and with their organisation into units based on lithologic character.

(ii) Lithostratigraphic classification is the organisation of rock strata into units on the basis of their lithologic character. (iii) A lithostratigraphic unit is a body of rock strata that is unified by consisting dominantly of a certain lithologic type or combination of lithologic types. It may consist of sedimentary, or igneous, or metamorphic rocks, or of an association of two or more of these. The critical requirement of the unit is a substantial

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(c) Kinds of lithostratigraphic units (i)

The conventional hierarchy of formal lithostratigraphic terms is as follows:

Group

two or more formations

Formation

primary unit of lithostratigraphy

Member

named lithologic entity within a formation

Bed

named distinctive layer in a member or formation

(ii) Formation The formation is the primary formal unit of lithostratigraphic classification. The thickness of units of formation rank follows no standard and may range from less than a metre to several thousand metres, depending on the size of units locally required to best express the lithologic development of a region.

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Formations may be composed of sedimentary rocks, or extrusive igneous rocks, or metamorphic rocks, or under some circumstances associations of two or more of these types of rock. (iii) Member A member is the formal lithostratigraphic unit next in rank below a formation and is always a part of a formation. It is recognised as a named entity within the formation because it possesses lithologic characters distinguishing it from adjacent parts of the formation. No fixed standard is required for the extent or thickness of a member. A member may extend laterally from one formation to another. (iv) Bed A bed is the smallest formal unit in the hierarchy of lithostratigraphic units. It is a unit layer in a stratified sequence of rocks which is lithologically distinguishable from other layers above and below. Customarily only distinctive beds (commonly known as marker beds) are given proper names and considered formal lithostratigraphic units. In relatively unexplored country where a formal and properly surveyed hierarchy of formations and groups cannot always be established initially, the use of a geographic name coupled with ‘beds’ (uncapitalised) will be accepted as a temporary informal designation.

Note 9. Use of ‘Group’ or ‘beds’ for poorly identified sequences ‘Group’ should be used only where the upper and lower limits of the unit can be identified and specified. A unit should be named and designated as ‘ . . . beds’ only when it is essential for stratigraphic classification or descriptive purposes (see Note 3). The geographic component should still be reserved with the Central Registry.

Note 10. Status of former ‘Beds’ units The term ‘Beds’ has been used under the provisions of the Australian Code (Article 27) for a sequence of poorly known strata, but in the ISG ‘Beds’ has a very different connotation. In future references to such units, the term ‘Beds’ should be changed to the informal term ‘beds’, and the unit should be regarded as an informal unit until further work is carried out. Later work may enable the unit to be redefined as a formation or as a group. (v) Group A group is the formal lithostratigraphic unit

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next in rank above a formation. The term is applied most commonly to a sequence of two or more contiguous associated with significant unifying lithologic features in common. The proposal for recognition of a group should outline clearly the unifying characteristics on which it is based and the formations of which it is composed.

Note 11. Establishment of a unit at group level without constituent formations when it is expected that formations will later be established It is recommended that stratigraphers should avoid establishing groups without constituent formations in anticipation of the possible action of future field workers. It is considered preferable to establish the unit as a formation and allow future workers to subdivide it, establish constituent formations, and change the rank of the original formation to group. The name of a group should preferably be derived from an appropriate geographic feature near the type areas of its component formations.

Note 12. Lithologic term in name of group In the special circumstance where a group consists of formations of the same or similar lithology, an appropriate lithologic term may be included in the name of the group if it is desired to indicate the character of the whole group. The component formations of a group are not necessarily everywhere the same.

Note 13. Reduction in rank from group to formation in lateral extensions of a unit without constituent formations It is recommended that the rank of group be retained, rather than the unit be permitted to carry the name of ‘. . . Group’ and ‘ . . . Formation’. (vi) Subgroup and supergroup A group may on occasion be divided into subgroups. The term supergroup may be used for several associated groups, or for associated formations and groups with significant features in common. (vii) Complex A complex is a lithostratigraphic unit composed of diverse types of any class or classes of rock (sedimentary, igneous, metamorphic) and characterised by highly complicated structure.

Note 14. Complex It is desirable to confine the term ‘Complex’ to a large

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mass of diverse rocks. Such a mass is unlikely to have the rank of formation or member; rather it is likely to consist of sequences which, if mappable, would constitute a group, supergroup or number of groups.

(ii) A unit-stratotype section (holostratotype) is often usefully supplemented by one or more auxiliary reference sections (hypostratotypes).

(viii) Informal lithostratigraphic units Informal lithostratigraphic units include lithologic bodies to which casual reference is made but which cannot be justified as formal units (eg shaly zones, sandy beds, coal measures).

Note 15. Coal measures Australian practice accepts ‘Coal Measures’ as a formal unit name equivalent in rank to group, subgroup, or formation. The term ‘seam’ is an informal term. Where individual coal seams are named with a geographic component they should be defined as formations or members, and named accordingly, eg Bulli Coal, Balgownie Coal Member. (ix) Some special aspects of igneous rocks Igneous rock bodies of more or less tabular form, conforming to the general stratification of the rock section, may constitute the basis for lithostratigraphic units. However, many igneous rocks occur as bodies injected across the dominant stratification of the section. They are an important part of the lithologic picture.

Note 16. Names of cross-cutting igneous bodies Such bodies are normally quite distinct from the surrounding rock unit, and if named have names of the same style as stratigraphic units, ie geographic name followed by lithological term. For stratigraphic nomenclature purposes they should therefore be treated as stratigraphic units and should be named as far as possible according to the principles in 5(f). (d) Procedures for establishing lithostratigraphic units (i)

Each named lithostratigraphic unit of whatever rank should have a clear and precise standard definition based on the fullest possible knowledge of its lateral and vertical variations. The designation of a type section (unit-stratotype) is essential in the definition of a lithostratigraphic unit. The unit, as recognised elsewhere, may contain a greater or lesser thickness of strata than in the stratotype, and may span a greater or lesser time interval than the stratotype. The only critical requirement of the unit as identified elsewhere is that it has essentially the same lithology and relative stratigraphic position as in the stratotype.

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(iii) Boundaries of lithostratigraphic units are placed at positions of lithologic change. (e) Procedures for extending lithostratigraphic units—lithostratigraphic correlation A lithostratigraphic unit and its boundaries should be extended away from the type locality only as far as the definitive lithologic features on which the unit was based in its type section are known to exist. (f) Naming of a lithostratigraphic units The name of a lithostratigraphic unit should be formed from the name of an appropriate local geographic feature, combined with the appropriate term for its rank (group, formation, member, bed), or with the name of the dominant rock type of which the unit is composed, or with both. Descriptive adjectives should not be included.

Note 17. Geographic component of name Authors have the option of using the full geographic name, consisting of both proper name and feature term (eg Mount Bowen, Turpentine Creek), or using only the proper name (Bowen, Turpentine) providing no confusion can arise; however the essential part of the geographic name is regarded as the proper name. Authors are encouraged to use the proper name only.

Note 18. Abbreviation of formal name after first reference Unit names are often used incorrectly by later authors; eg Kombolgie Formation appears as Kombolgie Sandstone, or the incorrect rank is used. It is recommended that the full stratigraphic name be used as much as possible.

Note 19. Change of lithological term for local or regional variation in a unit Change of the lithological term is undesirable for local variations in a unit, but may be desirable for regional variations. Reasons for any change should be fully explained. (i)

Geographic Component of name a.

Source. The geographic name should be the name of a natural or artificial feature at or near which the lithostratigraphic unit is typically developed (see Note 17).

Note 20a. Scarcity of geographic names

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The names of landholdings, parishes and counties given on cadastral maps are a fruitful source of names for stratigraphic units. Should there be no available or suitable geographic name, a name for an unnamed feature may be proposed to the relevant authority. b.

Duplication. Duplication of geographic names should be avoided (see Section 3(n); also Notes 8, 17, and 20).

c.

Names for parts of units. The same name should not be applied both to the unit as a whole and to a part of it. The terms lower, middle, and upper should not be used for formal subdivisions of a lithostratigraphic unit.

d.

Spelling. Spelling of the geographic component of a lithostratigraphic name should conform to the usage of the State that contains the type locality.

e.

Changes in geographic names. Change in the name of a geographic feature does not entail change of the corresponding name of a stratigraphic unit.

f.

Inappropriate names. A name that suggests some well-known locality, region, or political division should not, in general, be applied to a unit typically developed in another less well-known locality of the same name.

g.

Names of off-shore lithstratigraphic units. If the offshore well in which a new lithostratigraphic unit has been penetrated has been given a name taken from coastal, oceanographic, or other features, this name can be used for a subsurface unit providing that the requirements of Section 3(c) are followed.

For intrusive igneous rocks, the lithologic terms should express the name of the dominant rock type, for example, Dido Granodiorite.

Note 22. Use of the same geographic name for a stratigraphic unit and a structural or form feature (eg fault, batholith, dyke) This usage is allowable provided there is no likelihood of confusion. The stratigraphic name and the form name should apply to precisely the same rock mass. (iii) Preservation of traditional names Although it is strongly urged that all new lithostratigraphic units be named in accordance with the recommendations of this chapter, it is realised that there are many well-established and traditionally used lithostratigraphic units, of long historical standing, for which exception should be made. (g) Revision of lithostratigraphic units (i)

A change in the lithologic term applied to a lithostratigraphic unit does not necessarily require a new geographic term. If the original designation is not everywhere applicable, the term ‘Formation’ may be preferable.

(ii) Change in rank of a lithostratigraphic unit does not require alteration of the geographic part of its name. It is possible for a member to become a formation, or vice versa, and for a formation to become a group or vice versa.

Note 20b. Use of well names In Australia, this restricted use of well names recommended by the ISG has been unable to supply enough geographic names for offshore units. All wells are now regarded as geographic localities in their own right and may be used for naming lithostratigraphic units. (ii) Lithologic component of name Where a lithologic term is used in the name of a lithostratigraphic unit, the simplest generally acceptable term is recommended (eg limestone, sandstone, granite, serpentinite). Lithogenetic terms such as ‘turbidite’ or ‘flysch’ should be avoided.

Note 21. Use of ‘Volcanics’ and Metamorphics’ as the lithological term of stratigraphic names These terms are useful in Australian stratigraphy, and it is proposed to continue their use, but only as formation terms.

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6. SEQUENCE STRATIGRAPHIC UNITS Sequence stratigraphy is the study of genetically related packages of sediments in a chronostratigraphic framework. In the most commonly used scheme, the fundamental unit is the sequence, which is bounded above and below by unconformities and their correlative conformities (Van Wagoner et al, 1988). There is at present no agreement within Australia or elsewhere on how sequence units should be defined, what the hierarchy of those units should be, or how they should be named. It is apparent, however, that as a sequence can extend from onshore subaerial deposits to shallow marine shelf and deep sea turbidite deposits, there can be no type sections as in lithostratigraphy. Instead, a sequence must be defined in terms of its sequence boundaries, and these should have a type locality. A Variety of units of different rank have been used, up to at least sixth order, the most common being the supersequence and the megasequence. Because most authors have left their interpreted units in an informal state, the matter of how to name them has not

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arisen until recently. Although no scheme for naming sequence units exists yet, the Stratigraphic Names Committee recommends that the names not make use of geographic names as in lithostratigraphy, and that the names of lithostratigraphic units not be re-used for sequence units, particularly if the correspondence between the two types of units is not precise. Workers wishing to set up formal sequence stratigraphic units should contact their local Divisional State or Territory Stratigraphic Names Subcommittee, or the National Convener, for any news on progress in setting up guidelines for these units.

7. IGNEOUS GEOCHEMICAL UNITS The study of the geochemistry of igneous units, particularly granitoids and their related volcanics, has led to the grouping of lithological igneous units into higher rank geochemical units called suites and supersuites. A suite is a body or bodies of igneous rocks in whatever form they occur (eg pluton, dyke, sill, flow) that is considered co-magmatic on the basis of some, but not necessarily all, of the criteria of field evidence, petrography, geochemistry, geochronology, and geophysics. In defining a suite, the same general principles apply as in defining a group in lithostratigraphy, ie the component units should be listed, the characteristics on which the suite is based should be outlined, and the name should be derived from an appropriate geographic locality followed by the term Suite. Usually one of the component units is designated as the type unit of the suite. A supersuite is a group of suites and individual formation rank units that are considered to be of similar petrogenesis, but not necessarily co-magmatic, on the basis of some, but not necessarily all, of the criteria of field evidence, petrography, geochemistry, geochronology, and geophysics. In defining a supersuite, the same general principles apply as in defining a suite. Usually one of the component suites is designated as the type unit of the supersuite. Although it has been the practice in some regions to give suites and supersuites the same geographic name as the designated type units, this is not recommended by the Stratigraphic Names Committee. However, existing suite and supersuite names should not be changed solely for this reason, especially if doing so would cause confusion. At the time of writing, there is still an on-going debate regarding the classification and nomenclature of igneous geochemical units, and changes and elaborations to the guidelines are possible. The local Divisional State or Territory Stratigraphic Names Subcommittee, or the National Convener, should be contacted for the latest developments.

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8. AUSTRALIAN PROCEDURES (a) Administrative structure The machinery set up to provide orderly use of stratigraphic nomenclature in Australia consists of: (i)

The Stratigraphic Names Committee of the Geological Society of Australia, which consists of all members of the respective Divisional Subcommittees administered by its Convener;

(ii) Divisional Stratigraphic Names Subcommittees, which are responsible for stratigraphic nomenclature matters within their own Divisions; and (iii) The Central Register of Stratigraphic Names, which is maintained by the Australian Geological Survey Organisation, Canberra, and is compiled from all publications received in the Australian Geological Survey Organisation Library. (b) Reservation of names for proposed units (i)

The Query Stratigraphic Names Database should first be searched on the World Wide Web (WWW). This is reached on the AGSO Web site at http://www.agso.gov.au by clicking on Services, then Australian Stratigraphic Names Database, and using the search engine. If the name is found here it is available only for the unit to which the published name refers.

(ii) If the proposed name is not found on the WWW, then the appropriate volumes of the Lexique Stratigraphique International (Subcommission for the Stratigraphic Lexicon, 1958, 1959, 1962, 1963, 1966, 1975) may be consulted if available, or the local State or Territory Subcommittee on Stratigraphic Nomenclature may be asked for advice on the availability of the name. (iii) If the above searches do not locate any prior usage of the proposed name, the name should be referred to the Stratigraphic Index Officer, Australian Geological Survey Organisation, GPO Box 378, Canberra ACT 2601, who will advise whether the name is available or not. (The e-mail at the time of writing is [email protected], but this will change with time). (iv) If the name is pre-empted, the author is invited to submit alternatives. Where there is room for doubt, or a judgement is required, the Stratigraphic Index Officer

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refers the inquiry to the National Convener of the Stratigraphic Names Committee. (v) If the name is available, it is reserved for five years for the author, who is invited to complete a definition form and obtain approval for the completed definition from the relevant Divisional Subcommittee. (vi) Application may be made for the re-use of abandoned names, and in some circumstances approval may be given (see Section 3(1) Note 8a). (c) Approval of definitions of units before publication The completed definitions form should be sent by mail or e-mail to the Subcommittee for the State or Territory in which the unit occurs. Once the definition is approved, it is lodged with the Central Register, where it is available for reference. Reservation of a name and getting approval for the definition of a unit give no standing to that unit. Priority and standing are established only by publishing in a recognised scientific or technical publication (see ISG, 3.B.4 and Note 5). Definitions should be published, if possible, in the form approved by the Divisional Subcommittee, and preferably in the same publication in which the name of the unit is first used. (d) Central Register of Stratigraphic Names All information indexed prior to 1979 is held on cards. All articles indexed since 1969, and some from previous years, have been entered into a computer database, and work is proceeding to enter the remainder. The following major indexes are available: Author Stratigraphic name 1:250 000 sheet area Subject (using AMF Thesaurus for key words) Reserved name Approved definitions by Divisional Subcommittees These may be accessed via any field or combination of fields. As new data and changes in data are recorded, the Australian Stratigraphic Names Database on the world wide web is kept up to date.

7. ACKNOWLEDGEMENTS Dr E K Carter was the initiator of the Field Geologist’s Guide and a major contributor to several draft versions. Committee members, Geological Society members, and Geological Survey staff all offered comments which helped to mould the Guide into its published form

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(Staines, 1985). The publishers of the ISG, John Wiley and Sons, gave permission to reproduce extracts from Chapters 2 to 5 of the ISG, after representations by Dr Hollis D Hedberg and Dr Amos Salvador.

8. REFERENCES Australian Code of Stratigraphic Nomenclature, 1973 (4th edition, reprinted with corrigenda and additional notes), Geol Soc Aust J 20(1):105 - 112. Brakel, A T, 1989. Proposals for the re-use of invalid and superseded stratigraphic names in Australia, Record 1989/51 (Bureau of Mineral Resources: Australia). Hedberg, H D (Ed), 1976. International Stratigraphic Guide (John Wiley: New York). Salvador, A (Ed), 1994. International Stratigraphic Guide (International Union of Geological Sciences, and Geological Society of America). Staines, H R E, 1985. Field geologist’s guide to lithostratigraphic nomenclature in Australia, Aust J Earth Sci, 32:83 - 106. Subcommission for the Stratigraphic Lexicon, 1958. Lexique Stratigraphique International, Volume 6 Oceania, Fascicule 5a, Queensland (Centre National de la Recherche Scientifique: Paris). Subcommission for the Stratigraphic Lexicon, 1958. Lexique Stratigraphique International, Volume 6 Oceania, Fascicule 5e, South Australia (Centre National de la Recherche Scientifique: Paris). Subcommission for the Stratigraphic Lexicon, 1959. Lexique Stratigraphique International, Volume 6 Oceania, Fascicule 5b, New South Wales (Centre National de la Recherche Scientifique: Paris). Subcommission for the Stratigraphic Lexicon, 1959. Lexique Stratigraphique International, Volume 6 Oceania, Fascicule 5d, Tasmania (Centre National de la Recherche Scientifique: Paris). Subcommission for the Stratigraphic Lexicon, 1962. Lexique Stratigraphique International, Volume 6 Oceania, Fascicule 5g, Northern Territory (Centre National de la Recherche Scientifique: Paris). Subcommission for the Stratigraphic Lexicon, 1963. Lexique Stratigraphique International, Volume 6 Oceania, Fascicule 5f, Western Australia (Centre National de la Recherche Scientifique: Paris). Subcommission for the Stratigraphic Lexicon, 1966. Lexique Stratigraphique International, Volume 6 Oceania, Fascicule 5c, Victoria (Centre National de la Recherche Scientifique: Paris). Subcommission for the Stratigraphic Lexicon, 1975. Lexique Stratigraphique International, Volume 6 Oceania, Fascicule 5h, Australia Generalities (Centre National de la Recherche Scientifique: Paris). Vab Wagoner, J C, Posamentier, H W, Mitchum, R M, Vail, P R, Sarg, J F, Loutit, T S and Hardenbol, J, 1988. An overview of the fundamentals of sequence stratigraphy and key definitions, in Sea-level changes: an integrated approach, SEPM Special Publication 42, (Eds: C K Wilgus, B S Hastings, H W Posamentier, J C Van Wagoner, C A Ross and C G St C Kendall) pp 39 - 45.

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5.8. CHECK LISTS FOR RECORDING OUTCROP INFORMATION A description of a rock unit should convey to the reader a factual picture (in words) of the unit, its inherent properties, and its characteristics. The description should be systematic and concise. Completeness should not suffer at the expense of brevity, however, because it is from the description of the rock unit that the correlation and history are inferred. While it is not practical to impose a fixed system or order for describing lithologic units, especially in the individual’s notebook in the field, uniformity in sequence of description makes for clarity. A logical procedure in describing an outcrop is to first record the location, the nature of the outcrop, the attitude of the bed, the rock-type (eg sandstone). Following the rock-type, list those characteristics and properties which make it distinctive. (Moran, W R, 1958. Handbook for Geologists, Union Oil Co. of California.) The following list of observations may be followed in sequence: 1.

2.

3.

4. 5.

8.

Location: A full grid reference, the location method; map or GPS. The map datum and assumed accuracy of the GPS position. Sufficient extra description so that a person unfamiliar with the area may find the outcrop being described. Topography: Relief, shapes and arrangement of topographic units, linearity of features, relationship of lithological types to topographic forms, depth of weathering and typical weathering profile, maturity of topography. Nature of the vegetation: dominant species present, open or closed forest, woodland, shrubland, grassland, heath or nil vegetation. Nature of the outcrop to be described; including dimensions, form and shape. Lithological observations at outcrops: Colour of weathered and fresh surface, colour banding, degree and depth of weathering, grain size, mineral composition, field rock name (in capitals or underlined), relationship to units above and below (contact relationship and type). Presence of ‘economic’ minerals, degree of weathering, visual estimate of grade, position, type and dimensions of samples if taken.

6.

7.

attitude (for dykes, sills, etc.); fracture systems; lithologic structures (flow structure, schlieren, flow banding, segregations, etc.); contact relations; contact metamorphism; and inclusions (kind, shape, size, arrangement, and source); position and description of specimens collected. For a metamorphic rock, note further: Kind and degree of metamorphism; any preserved original structures (see igneous and sedimentary rocks, linear schistosity, gneissic structure, etc.); attitude of structure; relations of original structures to secondary structures; classification of original rock before metamorphism, position and description of specimens collected. For a sedimentary rock, note further: Whether detrital (clastic, fragmental), chemical, or organic; mode of occurrence (bed, lens, clastic pipe, clastic dyke); dimensions (thickness, lateral extent, etc.); attitude; direction of face in regions of intense folding; breadth of outcrop; degree of consolidation (unconsolidated, loose, compacted only by adhesive properties of some constituents, consolidated by virtue of a cement); composition, shape, size, and arrangement of constituents in detrital (fragmental) rocks, (larger fragments, matrix, cement); lithologic structures (cross-bedding, ripple-marks, sun cracks, local unconformity, contemporaneous deformation, etc); inclusions (concretions, nodules, geodes ); kinds, attitude, distribution, and abundance of fossils; stratigraphic sequence. Possible economic value, and for a possible petroleum source or reservoir horizon, details of porosity, petroliferous odour; description of samples or specimens collected.

9.

For a vein-type mineral deposit: Vein shape and dimensions; attitude and relation to host structures; wall rock alteration; type of vein-wall rock contact, arrangement of vein constituents (layering, cockade structures, zoning, etc), relative amount and grain size of minerals present; visual estimate of grade; position, type and dimensions of samples or specimens collected.

For an igneous rock, note further: Mode of occurrence; dimensions of igneous bodies;

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5.9. CLASSIFICATION OF FAULTS

1

CLASSIFICATION OF FAULTS BASED ON SLIP Oblique-slip

Translational movement

Dip- and strike-slip terms in combination: for example, normal right-slip fault, or, for a vertical fault. vertical oblique-slip fault, north side down and westward.

Dip-slip Normal-slip fault (hanging wall block down). Reverse-slip fault (hanging wall block up). For vertical faults, specify the movement of one block relative to the other; for example vertical dip-slip fault, east side down.

Rotational movement Plane fault 2

Strike-slip Right-slip (dextral) fault (opposite block to the right). Left-slip (sinistral) fault (opposite block to the left). For horizontal faults, describe the direction of movement of the hanging wall block; for example, horizontal north-east slip fault.

Clockwise-rotational fault (opposite block clockwise). Anticlockwise-rotational fault (opposite block anticlockwise). 1

From: Ragan, D M, 1973. Structural Geology. (John Wiley: New York), by permission, after Rickard (1972).

2.

Slip on curved fault surface may also occur.

Classification diagrams for translation faullts. (a) Dip-pitch triangular grid. (b) Fault categories on the dip pitch triangles. The special cases of dip-slip and strike-slip faults are shown shaded; the oblique-slip categories are blank.

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5.10. CLASSIFICATION OF FOLDS BY DIP ISOGONS AND BY HINGE SURFACE 1. BY DIP ISOGONS1

a

b

Construction of dip isogons

FOLD ORIENTATION

1.

From Ramsay, J G, 1967. Folding and Fracturing of Rocks. (McGraw-Hill: New York), by permission.

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2. BY HINGE SURFACEl Terms describing the attitude of folds Angle Term 0° Horizontal. 1°- 10° Sub-horizontal 10° - 30° Gentle 30° - 60° Moderate 60° - 80° Steep 80° - 89° Sub-vertical 90° Vertical

Example a b c 1.

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Dip of Hinge Surface 85° 70° 56°

Dip of hinge surface

Plunge of hinge line

Recumbent fold

Horizontal fold

Gently inclined fold Moderately inclined fold Steeply inclined fold

Gently plunging fold Moderately plunging fold Steeply inclined fold

Upright fold

Vertical fold

Plunge of Hinge Line 20° 45° 55°

Description of Fold Upright gently plunging Steeply inclined moderately plunging Moderately inclined reclined

From Ragan, D M, 1973. Structural Geology. (John Wiley: New York), by permission, after Rickard (1971).

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5.11. GRAPH SHOWING ANGLE OF TRUE DIP OR SLOPE, VERTICAL 1 EXAGGERATION, AND EXAGGERATED DIP

Example—with a vertical exaggeration of v/h = 10, a true dip of 6° is represented by an exaggerated dip of about 45°. 1. From Ragan, D M, 1968. Structural Geology. (John Wiley: New York), by permission.

5.12. SELECTED BIBLIOGRAPHY Harris, L B, 1986. Structural Controls of Gold Mineralization (Earth Resources Foundation: Sydney). Hobbs, B E, Means, W D, and Williams, P F, 1976. An Outline of Structural Geology (John Wiley: New York). Hopwood, T P, 1974. Structural geology and mineral exploration, A.M.F. course notes, Adelaide. McClay, K R, 1987. The Mapping of Geological Structures (Open University Press: Milton Keynes). Price, N J and Cosgrove, J W, 1990. Analysis of Geological Structures (Cambridge University Press: Cambridge).

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Ramsay, J G and Huber, M I, 1985. The Techniques of Modern Structural Geology, Vol 1 Strain Analysis, (Academic Press: London). Ramsay, J G and Huber, M I, 1987. The Techniques of Modern Structural Geology, Vol 2 Folds and Fractures (Academic Press: London). Simpson, C and Schmid, S M, 1983. An evaluation of criteria to deduce the sense of movement in sheared rocks, Geol Soc Amer Bull 81: 41-60. Turner, F J, and Weiss, L E, 1963. Structural Analysis of Metamorphic Tectonites (McGraw-Hill: New York). Weiss, L E, 1972. The Minor Structures of Deformed Rocks (Springer-Verlag: Berlin).

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6. GEOMETRIC AND SURVEYING DATA 6.1. FORMULAE FOR SOLUTION OF TRIANGLES1 FOR RIGHT ANGLE TRIANGLES

FOR OBLIQUE TRIANGLES

1.

From Peele, Robert, 1918. Mining Engineers’ Handbook, Vol II, third edition, pp 36-17 to 36-19 (John Wiley: New York), by permission.

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6.2.1. FORMULAE FOR AREA, PERIMETER ETC OF PLANAR FIGURES

1

Rectangle n Sides

Regular polygon

Triangle

Circular sector

Circular segment Quadrilateral

Parallelogram

Circular zone

Trapezoid Circular lune

1.

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From Peele, Robert, 1918. Mining Engineers’ Handbook, Vol II, third edition, pp 36-11 to 36-13 (John Wiley: New York), by permission.

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Circle

Ellipse

Parabola

Irregular figures

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6.2.2. FORMULAE FOR SURFACE AREA, VOLUME ETC OF SOLIDS

1.

274

1

From Peele, Robert, 1918. Mining Engineers’ Handbook, Vol II, third edition, pp 36-11 to 36-15 (John Wiley: New York), by permission.

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6.3. APPARENT DIP IN A DIRECTION NOT PERPENDICULAR TO THE STRIKE 1. TABLE OF TRUE AND APPARENT DIP

1

ANGLE BETWEEN STRIKE AND DIRECTION OF SECTION 80°

TRUE DIP 10° 15° 20° 25° 30° 35° 40° 45° 50° 55° 60° 65° 70° 75° 80° 85°

75°

70°

65°

60°

55°

50°

45°

40°

35°

30°

25°

20°

15°

10°

5°

6° 9° 12° 15° 18° 22° 26° 30° 34° 39° 45° 51° 58° 65° 73° 81°

5° 8° 10° 13° 16° 19° 23° 27° 31° 36° 41° 46° 54° 62° 71° 80°

4° 6° 9° 11° 14° 16° 20° 23° 27° 31° 36° 42° 49° 58° 67° 78°

3° 5° 7° 9° 11° 13° 16° 19° 22° 26° 30° 36° 43° 52° 63° 76°

3° 4° 5° 7° 9° 10° 12° 15° 17° 20° 24° 29° 35° 44° 56° 71°

2° 3° 4° 5° 6° 7° 8° 10° 12° 14° 17° 20° 25° 33° 45° 63°

1° 1° 2° 2° 3° 4° 4° 5° 6° 7° 9° 11° 13° 18° 26° 45°

APPARENT DIP 10° 15° 20° 25° 30° 35° 40° 45° 50° 55° 60° 65° 70° 75° 80° 85°

10° 14° 19° 24° 29° 34° 39° 44° 49° 54° 59° 64° 69° 74° 80° 85°

9° 14° 19° 24° 28° 33° 38° 43° 48° 53° 58° 64° 69° 74° 79° 85°

9° 14° 18° 23° 28° 32° 37° 42° 47° 52° 58° 63° 69° 74° 79° 84°

9° 13° 18° 22° 27° 31° 36° 41° 46° 51° 56° 62° 68° 73° 78° 84°

8° 12° 17° 21° 25° 30° 35° 39° 44° 49° 55° 60° 67° 72° 78° 84°

8° 12° 16° 20° 24° 28° 33° 37° 42° 48° 53° 59° 65° 71° 77° 83°

7° 10° 14° 18° 22° 26° 31° 35° 40° 45° 51° 57° 63° 69° 76° 83°

6° 10° 13° 17° 20° 24° 28° 33° 37° 43° 48° 54° 60° 67° 75° 82°

Values for true dip etc not stated above may be calculated from: tan (apparent dip) = tan (true dip) × sin (angle between strike and direction of section). 2. NOMOGRAM FOR ESTIMATING APPARENT DIP

2

1.

From Forrester, J D, 1946. Principles of Field and Mining Geology (John Wiley: New York), by permission.

2.

From Palmer, H S, 1918. New graphic method for determining the depth and thickness of strata and the projection of dip, USGS Prof. Paper 120-G, pp 123- 128, by permission.

Example: if true dip is 43°, the apparent dip on a vertical section making a 35° angle with the strike of the bedding would be 28°.

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6.4. TABLE OF SLOPE ANGLES, GRADIENTS, AND PER CENT GRADE Gradient, grade, slope and inclination are synonymous. All are usually defined by a vertical rise or fall over a horizontal distance, thus a fall of one unit vertically in 12 units horizontal distance may be stated as a negative gradient (grade, slope, inclination) of one in 12 (or 1:12). This slope may also be expressed as a grade of −8.33 per cent, a fall of 83.3 m per km, or slope angle of 4°46´ (tangent is 0.0833). The relationship between these terms is:

Slope angle ( φ ) is that for which tan φ = H V 100V = 100 tan φ. Per cent grade is = H

Gradient is 1:

Slope angle

Approx. gradient

% Grade

Slope angle

Approx. gradient

% Grade

0°01´ 0°02´ 0°03´ 0°04´ 0°05´ 0°06´ 0°07´ 0°08´ 0°09´ 0°10´ 0°11´ 0°12´ 0°13´ 0°14´ 0°15´ 0°16´ 0°17´ 0°18´ 0°19´ 0°20´ 0°21´ 0°22´ 0°23´ 0°24´ 0°25´ 0°26´ 0°27´ 0°28´ 0°29´ 0°30´

1:3437 1:1719 1:1146 1:859 1:688 1:573 1:491 1:430 1:382 1:344 1:313 1:286 1:264 1:246 1:229 1:215 1:202 1:191 1:181 1:172 1:164 1:156 1:149 1:143 1:138 1:132 1:127 1:123 1:119 1:115

0.03 0.06 0.09 0.12 0.15 0.17 0.20 0.23 0.26 0.29 0.32 0.35 0.38 0.41 0.44 0.47 0.49 0.52 0.55 0.58 0.61 0.64 0.67 0.70 0.73 0.76 0.79 0.81 0.84 0.87

0°31´ 0°32´ 0°33´ 0°34´ 0°35´ 0°36´ 0°37´ 0°38´ 0°39´ 0°40´ 0°42´ 0°44´ 0°45´ 0°46´ 0°48´ 0°50´ 0°52´ 0°54´ 0°56´ 0°58´ 1°00´ 1°05´ 1°09´ 1°20´ 1°26´ 1°43´ 2°00´ 2°17´ 2°35´ 2°52´

1:111 1:107 1:104 1:101 1:98 1:95 1:93 1:90 1:88 1:86 1:82 1:78 1:76 1:75 1:72 1:69 1:66 1:64 1:61 1:59 1:57 1:53 1:50 1:43 1:40 1:33 1:29 1:25 1:22 1:20

0.90 0.93 0.96 0.99 1.02 1.05 1.08 1.11 1.13 1.16 1.22 1.28 1.31 1.34 1.40 1.45 1.51 1.57 1.63 1.69 1.75 1.89 2.00 2.33 2.50 3.00 3.49 4.00 4.51 5.00

Field Geologists’ Manual

V H

Slope angle 3°00´ 3°26´ 3°30´ 4°00´ 4°30´ 4°34´ 5°00´ 5°09´ 5°30´ 5°43´ 6°00´ 6°51´ 7°00´ 7°58´ 8°00´ 8°32´ 9°00´ 9°05´ 10°00´ 11°00´ 11°19´ 12°00´ 13°00´ 14°00´ 15°00´ 16°00´ 17°00´ 18°00´ 19°00´ 20°00´

Approx. gradient 1:19 1:17 1:16 1:14 1:13 1:12.5 1:11.4 1:11.1 1:10.4 1:10.0 1:9.5 1:8.3 1:8.1 1:7.1 1:7.1 1:6.7 1:6.3 1:6.3 1:5.7 1:5.1 1:5.0 1:4.7 1:4.3 1:4.0 1:3.7 1:3.5 1:3.3 1:3.1 1:2.9 1:2.7

% Grade 5.24 6.00 6.12 6.99 7.87 8.00 8.75 9.01 9.63 10.00 10.51 12.01 12.28 13.99 14.05 15.00 15.8 16.0 17.6 19.4 20.0 21.3 23.1 24.9 26.8 28.7 30.6 32.5 34.4 36.4

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6.5. FIELD GRID SPACING AND ELEVATION CONVERSION TABLE HORIZ. SPACING REQUIRED SLOPE ANGLE 1° 2° 3° 4° 5° 6° 7° 8° 9° 10° 11° 12° 13° 14° 15° 16° 17° 18° 19° 20° 21° 22° 23°

278

20

25

30

40

50

60

70

80

90

100

PEG SPACING (SLOPE DISTANCE) / DIFFERENCE IN ELEVATION 20.0/ 0.4 20.0/ 0.7 20.0/ 1.0 20.0/ 1.4 20.1/ 1.7 20.1/ 2.1 20.2/ 2.5 20.2/ 2.8 20.3/ 3.2 20.3/ 3.5 20.4/ 3.9 20.4/ 4.3 20.5/ 4.6 20.6/ 5.0 20.7/ 5.4 20.8/ 5.7 20.9/ 6.1 21.0/ 6.5 21.2/ 6.9 21.3/ 7.3 21.4/ 7.7 21.6/ 8.1 21.7/ 8.5

25.0/ 0.4 25.0/ 0.9 25.0/ 1.3 25.1/ 1.7 25.1/ 2.2 25.1/ 2.6 25.2/ 3.1 25.2/ 3.5 25.3/ 4.0 25.4/ 4.4 25.5/ 4.9 25.6/ 5.3 25.7/ 5.8 25.8/ 6.2 25.9/ 6.7 26.0/ 7.2 26.1/ 7.6 26.3/ 8.1 26.4/ 8.6 26.6/ 9.1 26.8/ 9.6 27.0/ 10.1 27.2/ 10.6

30.0/ 0.5 30.0/ 1.0 30.0/ 1.6 30.1/ 2.1 30.1/ 2.6 30.2/ 3.2 30.2/ 3.7 30.3/ 4.2 30.4/ 4.8 30.5/ 5.3 30.6/ 5.8 30.7/ 6.4 30.8/ 6.9 30.9/ 7.5 31.1/ 8.0 31.2/ 8.6 31.4/ 9.2 31.6/ 9.7 31.7/ 10.3 31.9/ 10.9 32.1/ 11.6 32.4/ 12.1 32.6/ 12.7

40.0/ 0.7 40.0/ 1.4 40.1/ 2.1 40.1/ 2.8 40.2/ 3.5 40.2/ 4.2 40.3/ 4.9 40.4/ 5.6 40.5/ 6.3 40.6/ 7.1 40.7/ 7.8 40.9/ 8.5 41.1/ 9.2 41.2/ 10.0 41.4/ 10.7 41.6/ 11.5 41.8/ 12.2 42.1/ 13.0 42.3/ 13.8 42.6/ 14.6 42.8/ 15.4 43.1/ 16.2 43.5/ 17.0

50.0/ 0.9 50.0/ 1.7 50.1/ 2.6 50.1/ 3.5 50.2/ 4.4 50.3/ 5.3 50.4/ 6.1 50.5/ 7.0 50.6/ 7.9 50.8/ 8.8 50.9/ 9.7 51.1/ 10.6 51.3/ 11.5 51.5/ 12.5 51.8/ 13.4 52.0/ 14.3 52.3/ 15.3 52.6/ 16.2 52.9/ 17.2 53.2/ 18.2 53.6/ 19.2 53.9/ 20.2 54.3/ 21.2

60.0/ 1.1 60.0/ 2.1 60.1/ 3.1 60.1/ 4.2 60.2/ 5.2 60.3/ 6.3 60.5/ 7.4 60.6/ 8.4 60.8/ 9.5 60.9/ 10.6 61.1/ 11.7 61.3/ 12.8 61.6/ 13.9 61.8/ 15.0 62.1/ 16.1 62.4/ 17.2 62.7/ 18.3 63.1/ 19.5 63.5/ 20.7 63.9/ 21.8 64.3/ 23.0 64.7/ 24.2 65.2/ 25.5

70.0/ 1.2 70.0/ 2.4 70.1/ 3.7 70.2/ 4.9 70.3/ 6.1 70.4/ 7.4 70.5/ 8.6 70.7/ 9.8 70.9/ 11.1 71.1/ 12.3 71.3/ 13.6 71.6/ 14.9 71.8/ 16.2 72.1/ 17.5 72.5/ 18.8 72.8/ 20.1 73.2/ 21.4 73.6/ 22.7 74.0/ 24.1 74.5/ 25.5 75.0/ 26.9 75.5/ 28.3 76.0/ 29.7

80.0/ 1.4 80.0/ 2.8 80.1/ 4.2 80.2/ 5.6 80.3/ 7.0 80.4/ 8.4 80.6/ 9.8 80.8/ 11.2 81.0/ 12.7 81.2/ 14.1 81.5/ 15.6 81.8/ 17.0 82.1/ 18.5 82.4/ 19.9 82.8/ 21.4 83.2/ 22.9 83.7/ 24.5 84.1/ 26.0 84.6/ 27.5 85.1/ 29.1 85.7/ 30.7 86.3/ 32.3 86.9/ 34.0

90.0/ 1.6 90.1/ 3.1 90.1/ 4.7 90.2/ 6.3 90.3/ 7.9 90.5/ 9.5 90.7/ 11.1 90.9/ l2.6 91.1/ 14.3 91.4/ 15.9 91.7/ 17.5 92.0/ 19.1 92.4/ 20.8 92.8/ 22.4 93.2/ 24.1 93.6/ 25.8 94.1/ 27.5 94.6/ 29.2 95.2/ 31.0 95.8/ 32.8 96.4/ 34.6 97.1/ 36.4 97.8/ 38.2

100.02/ 1.75 100.06/ 3.49 100.14/ 5.24 100.24/ 6.99 100.38/ 8.75 100.55/ 10.51 100.75/ 12.28 100.98/ 14.05 101.25/ 15.84 101.54/ 17.63 101.87/ 19.44 102.23/ 21.26 102.63/ 23.09 103.06/ 24.93 103.53/ 26.79 104.03/ 28.67 104.57/ 30.57 105.15/ 32.49 105.76/ 34.43 106.42/ 36.40 107.11/ 38.39 107.85/ 40.40 108.64/ 42.45

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GEOMETRIC AND SURVEYING DATA

HORIZ. SPACING REQUIRED SLOPE ANGLE 24° 25° 26° 27° 28° 29° 30° 31° 32° 33° 34° 35° 36° 37° 38° 39° 40° 41° 42° 43° 44° 45°

20

25

30

40

50

60

70

80

90

100

PEG SPACING (SLOPE DISTANCE) / DIFFERENCE IN ELEVATION 21.9/ 8.9 22.1/ 9.3 22.3/ 9.8 22.4/ 10.2 22.7/ 10.6 22.9/ 11.1 23.1/ 11.5 23.3/ 12.0 23.6/ 12.5 23.8/ 13.0 24.1/ 13.5 24.4/ 14.0 24.7/ 14.5 25.0/ 15.1 25.4/ 15.6 25.7/ 16.2 26.1/ 16.8 26.5/ 17.4 26.9/ 18.0 27.3/ 18.7 27.8/ 19.3 28.3/ 20.0

27.4/ 11.1 27.6/ 11.7 27.8/ l2.2 28.1/ l2.7 28.3/ 13.3 28.6/ 13.9 28.9/ 14.4 29.2/ 15.0 29.5/ 15.6 29.8/ 16.2 30.2/ 16.9 30.5/ 17.5 30.9/ 18.2 31.3/ 18.8 31.7/ 19.5 32.2/ 20.2 32.6/ 21.0 33.1/ 21.7 33.6/ 22.5 34.2/ 23.3 34.8/ 24.1 35.4/ 25.0

32.8/ 13.4 33.1/ 14.0 33.4/ 14.6 33.7/ 15.3 34.0/ 16.0 34.3/ 16.6 34.6/ 17.3 35.0/ 18.0 35.4/ 18.7 35.8/ 19.5 36.2/ 20.2 36.6/ 21.0 37.1/ 21.8 37.6/ 22.6 38.1/ 23.4 38.6/ 24.3 39.2/ 25.2 39.8/ 26.1 40.4/ 27.0 41.0/ 28.0 41.7/ 29.0 42.4/ 30.0

43.8/ 17.8 44.1/ 18.7 44.5/ 19.5 44.9/ 20.4 45.3/ 21.3 45.7/ 22.2 46.2/ 23.1 46.7/ 24.0 47.2/ 25.0 47.7/ 26.0 48.2/ 27.0 48.8/ 28.0 49.4/ 29.1 50.1/ 30.1 50.8/ 31.3 51.5/ 32.4 52.2/ 33.6 53.0/ 34.8 53.8/ 36.0 54.7/ 37.3 55.6/ 38.6 56.6/ 40.0

54.7/ 22.3 55.2/ 23.3 55.6/ 24.4 56.1/ 25.5 56.6/ 26.6 57.2/ 27.7 57.7/ 28.9 58.3/ 30.0 59.0/ 31.2 59.6/ 32.5 60.3/ 33.7 61.0/ 35.0 61.8/ 36.3 62.6/ 37.7 63.5/ 39.1 64.3/ 40.5 65.3/ 42.0 66.3/ 43.5 67.3/ 45.0 68.4/ 46.6 69.5/ 48.3 70.7/ 50.0

65.7/ 26.7 66.2/ 28.0 66.8/ 29.3 67.3/ 30.6 68.0/ 31.9 68.6/ 33.3 69.3/ 34.6 70.0/ 36.1 70.8/ 37.5 71.5/ 39.0 72.4/ 40.5 73.2/ 42.0 74.2/ 43.6 75.1/ 45.2 76.1/ 46.9 77.2/ 48.6 78.3/ 50.3 79.5/ 52.2 80.7/ 54.0 82.0/ 56.0 83.4/ 57.9 84.9/ 60.0

76.6/ 31.2 77.2/ 32.6 77.9/ 34.1 78.6/ 35.7 79.3/ 37.2 80.0/ 38.8 80.8/ 40.4 81.7/ 42.1 82.6/ 43.7 83.5/ 45.5 84.4/ 47.2 85.5/ 49.0 86.5/ 50.9 87.6/ 52.8 88.8/ 54.7 90.1/ 56.7 91.4/ 58.7 92.8/ 60.8 94.2/ 63.0 95.7/ 65.3 97.3/ 67.6 99.0/ 70.0

87.6/ 35.6 88.3/ 37.3 89.0/ 39.0 89.8/ 40.8 90.6/ 42.5 91.5/ 44.3 92.4/ 46.2 93.3/ 48.1 94.3/ 50.0 95.4/ 52.0 96.5/ 54.0 97.7/ 56.0 98.9/ 58.1 100.2/ 60.3 101.5/ 62.5 102.9/ 64.8 104.4/ 67.1 106.0/ 69.5 107.6/ 72.0 109.4/ 74.6 111.2/ 77.3 113.1/ 80.0

98.5/ 40.1 99.3/ 42.0 100.1/ 43.9 101.0/ 45.9 101.9/ 47.9 102.9/ 49.9 103.9/ 52.0 105.1/ 54.1 106.1/ 56.2 107.3/ 58.4 108.6/ 60.7 109.9/ 63.0 111.2/ 65.4 112.7/ 67.8 114.2/ 70.3 115.8/ 72.9 117.5/ 75.5 119.3/ 78.2 121.1/ 81.0 123.0/ 83.9 125.1/ 86.9 127.3/ 90.0

109.46/ 44.52 110.34/ 46.63 111.26/ 48.77 112.23/ 50.95 113.26/ 53.17 114.34/ 55.43 115.47/ 57.74 116.66/ 60.09 117.92/ 62.49 119.24/ 64.94 120.62/ 67.45 122.08/ 70.02 123.61/ 72.65 125.21/ 75.36 l26.90/ 78.13 l28.68/ 80.98 130.54/ 83.91 132.50/ 86.93 134.56/ 90.04 136.73/ 93.25 139.02/ 96.57 141.42/ 100.00

NOTE: The peg spacing (slope distance) lengths shown are intended for use in rapidly pegging a reasonably accurate grid, using compass, clinometer and tape. The differences in elevation may be recorded, from which approximate topographic contours may be derived.

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6.6.1. STADIA FORMULA AND METHOD OF CHECKING A THEODOLITE

1

STADIA FORMULA

CHECKING A THEODOLITE

Practically all the theodolites in use in Australia are internal focusing, ie the image is seen at the centre of the telescope, and have a staff multiplication factor of 100. This factor enables a simple calculation of slope distance as 100 times the staff intercept. For a typical setting, as below:

No adjustment should be required to the horizontal angle, unless the instrument has been badly treated, in which case it should be serviced by a professional. However, checking and adjusting the vertical circle is required regularly, and may be carried out as stated below:

H.I. is height of instrument above peg A V is vertical angle s is stadia ( slope) distance, theodolite to staff m is mid reading on the staff H is horizontal distance, peg A to peg B D is difference in elevation, peg A to peg B H = s.cos2 V s  D = H.I. +  sin 2V − m 2  Stadia tables provide a listing of cos2V and ½ sin 2V for a range of angles V and stadia distance (s).

1.

Place two pegs A and B, in an open area, with A and B about 70 to 100 m apart and with B less than 2 m higher than A. Drive both pegs in until the tops are at ground level.

2.

Set up the theodolite perfectly level beside A, so that the telescope just clears the staff when placed on A. With the telescope level, ie with vertical angle 0°00´, note the central cross hair on the staff as reading A1. Then read the height with the staff at peg B, with a level sight, calling this B1.

3.

Set up the instrument beside peg B, as in the previous case, and read B2 and A2. Leave the theodolite set up at peg B.

4.

Calculate the two differences in elevation B1 − A1 and B2 − A2. The mean of these two levels, ie (B1 − A1) + (B2 − A2) M= 2 is the true difference in elevation between A and B.

5.

With the theodolite remaining at peg B and the staff on peg A adjust the vertical circle until a vertical angle of 0°00´ (ie a level sight) shows a reading of the staff of B2 + M.

6. A1 B1 Difference

4.86 2.98 1.88

B2 A2

5.14 6.86 1.72

Typical readings are: 1.

280

From Peele, Robert, 1918. Mining Engineers’ Handbook, Vol. II, third edition, pp 17-08, 09 (John Wiley: New York), by permission.

M = ½ (1.88 + 1.72) = 1.80 Adjust the vertical circle screws so that a level sight gives a mid wire reading (A2) of 5.14 + 1.80 = 6.94.

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GEOMETRIC AND SURVEYING DATA

6.6.2. STADIA TABLES Slope angle 0°20´ 0°40´ 1°00´ 1°20´ 1°40´ 2°00´ 2°20´ 2°40´ 3°00´ 3°20´ 3°40´ 4°00´ 4°20´ 4°40´ 5°00´ 5°20´ 5°40´ 6°00´ 6°20´ 6°40´ 7°00´ 7°20´ 7°40´ 8°00´ 8°20´ 8°40´ 9°00´ 9°20´ 9°40´ 10°00´ 10°20´ 10°40´ 11°00´ 11°20´ 11°40´ 12°00´ 12°20´ 12°40´ 13°00´ 13°20´ 13°40´ 14°00´ 14°20´ 14°40´ 15°00´ 1.

Horiz. distance 100.00 99.99 99.97 99.95 99.92 99.88 99.83 99.78 99.73 99.66 99.59 99.51 99.43 99.34 99.24 99.14 99.03 98.91 98.78 98.65 98.51 98.37 98.22 98.06 97.90 97.73 97.55 97.37 97.18 96.98 96.78 96.57 96.36 96.14 95.91 95.68 95.44 95.19 94.94 94.68 94.42 94.15 93.87 93.59 93.30

Vertical component 0.58 1.16 1.75 2.33 2.91 3.49 4.07 4.65 5.23 5.80 6.38 6.96 7.53 8.11 8.68 9.25 9.83 10.40 10.96 11.53 12.10 12.66 13.22 13.78 14.34 14.90 15.45 16.00 16.55 17.10 17.65 18.19 18.73 19.27 19.80 20.34 20.87 21.39 21.92 22.44 22.96 23.47 23.99 24.49 25.00

Slope angle 15° 20´ 15° 40´ 16° 00´ 16° 20´ 16° 40´ 17° 00´ 17° 20´ 17° 40´ 18° 00´ 18° 20´ 18° 40´ 19° 00´ 19° 20´ 19° 40´ 20° 00´ 20° 20´ 20° 40´ 21° 00´ 21° 20´ 21° 40´ 22° 00´ 22° 20´ 22° 40´ 23° 00´ 23° 20´ 23° 40´ 24° 00´ 24° 20´ 24° 40´ 25° 00´ 25° 20´ 25° 40´ 26° 00´ 26° 20´ 26° 40´ 27° 00´ 27° 20´ 27° 40´ 28° 00´ 28° 20´ 28° 40´ 29° 00´ 29° 20´ 29° 40´ 30° 00´

1

Horiz. distance 93.01 92.71 92.40 92.09 91.77 91.45 91.12 90.79 90.45 90.11 89.76 89.40 89.04 88.67 88.30 87.93 87.54 87.16 86.77 86.37 85.97 85.56 85.15 84.73 84.31 83.89 83.46 83.02 82.58 82.14 81.69 81.24 80.78 80.32 79.86 79.39 78.92 78.44 77.96 77.48 76.99 76.50 76.00 75.50 75.00

Vertical component 25.50 26.00 26.50 26.99 27.48 27.96 28.44 28.92 29.39 29.86 30.32 30.78 31.24 31.69 32.14 32.58 33.02 33.46 33.89 34.31 34.73 35.15 35.56 35.97 36.37 36.77 37.16 37.54 37.93 38.30 38.67 39.04 39.40 39.76 40.11 40.45 40.79 41.12 41.45 41.77 42.09 42.40 42.71 43.01 43.30

Factors for calculating horizontal distance and difference of elevation, for a staff intercept of 100.

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6.7. AIRPHOTO SCALE NOMOGRAM AND FORMULA

AIR PHOTO SCALE FORMULA 1.

From the information supplied on the margin of the airphoto, when the elevation of a point, or the average ground height, is known, then the scale is:

1:

282

altimeter ht. − ground ht. focal length of camera lens

2.

When an airphoto distance can be related to an accurately known ground distance from a topographic map then the airphoto scale is:

1:

map dist. × map scale factor airphoto distance

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GEOMETRIC AND SURVEYING DATA

6.8. DETERMINATION OF THE LINE OF INTERSECTION OF TWO PLANES (TANGENT VECTOR METHOD) Assume a bed dipping towards 054° at an angle of 30°, and a fault dipping at 60° towards 164°. To find the plunge of the line of intersection of the two planes: 1.

Draw the two planes as tangent vectors.

2.

Draw a line through the origin, at right angles to the line joining the two tangent vectors.

3.

Read the bearing of the line of intersection with a protractor (090°) , and measure the length of the tangent vector (0.465 units). This is the tangent of the angle of dip of the line of intersection (25°).

6.9. GRAPHICAL SOLUTION OF THE THREE POINT PROBLEM The dip and strike of any planar horizon may be found if the position and elevation of any three points on the horizon are known. A typical example is : Coordinates Point

N

E

Elevation

A B

150

72

1250

320

260

C

900

−20

200

1332

Plot A, B and C on any convenient scale, as shown opposite. Draw a line joining the points of greatest and least heights (B and C). A line giving the strike will pass from the point of intermediate height (A) through a point D along BC. To find D, measure the length BC (350), and calculate the length of BD from— height A − height B BD 1250 − 900 350 = = = height C − height B BC 1332 − 900 432 = 0.81 BD = 0.81 × BC = 0.81 × 350 = 283.5 Line AD is thus the strike direction, and the bearing can be read using a protractor (127°). The dip is found by constructing a line at right angles to AD, through B, which meets the (strike) line AD at E. Draw BF perpendicular to BE, and of length equal to the difference in height between A and B, ie 350. The angle BEF is the dip angle (54°).

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6.10. ORTHOGRAPHIC AND WULFF (EQUAL ANGLE) STEREONETS, SCHMIDT (EQUAL AREA) STEREONET AND CONTOURING DEVICE

ORTHOGRAPHIC NET

284

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N

S

WULFF NET

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SCHMIDT NET

286

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DEVICE FOR THE CONTOURING OF DATA POINTS PLOTTED IN EQUAL AREA PROJECTION The ellipses are projections of circles of one per cent area from the surface of the reference sphere. The data points plotted in equal area projection on a tracing overlay are rotated at five or ten degree increments over the contouring device. At each increment the number of data points falling within each of the ellipses is recorded at the ellipse centre positions on a second transparent counting overlay. After 180 degrees

rotation the counting is complete. By dividing the total number of data points by 100 the data point density required for a one per cent contour per one per cent area is derived. The data point densities for various percentage increments are determined as multiples of the one per cent density value and the counting overlay is contoured accordingly.

CONTOURING DEVICE

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7. ENGINEERING GEOLOGY

1

7.1.1. FIELD GEOTECHNICAL TESTING METHODS2 Many techniques and tests are available for on-site geotechnical investigations. Listed are a range of techniques that are commonly considered. Other more specialised techniques and tests are available and can also be considered when circumstances dictate. (a)

(iii) In situ stress measurement. (f)

(iii) Borehole logging.

(iii) California bearing ratio. (g)

(iii) Magnetics.

(h)

Blasting tests and blast vibration monitoring.

(i)

Topographic studies: (i)

(iii) Photogrammetry and photo interpretation.

Drilling and sampling:

(iv) Remote sensing.

Rotary core drilling.

(ii) Auger boring and coring.

(j)

(v) Disturbed sampling.

(iii) Pumping tests.

In situ subsurface testing:

(iv) Groundwater level measurement.

Standard penetration tests.

(v) Chemical quality.

(ii) Dynamic cone penetrometer.

and

microbiological

water

(iii) Static cone penetrometer.

(k)

Seismicity studies:

(iv) Vane shear test.

(l)

Exploratory pits, trenches, shafts, tunnels and galleries.

1.

This chapter was revised by geotechnical engineer R L Smith of Gutteridge, Haskins and Davey Pty Ltd, Perth.

2.

From Appendix B of Australian Standard 1726-1993, by permission.

(v) Pressuremeter. (vi) Impression packer. (vii) Core orientation device. (viii)Borehole periscope TV and photography. (e)

Packer tests.

(ii) Rising head, constant head and falling head tests.

(iv) Undisturbed sampling.

(i)

Groundwater studies: (i)

(iii) Percussion drilling.

(d)

Topographic mapping.

(ii) Terrain evaluation.

(v) Subsurface radar (i)

Inclinometer.

(ii) Extensometer.

(iv) Geophysical borehole logging. (c)

Slope and excavation stability monitoring: (i)

Seismic refraction.

(ii) Resistivity and conductivity.

Plate bearing test.

(ii) Density measurement. of

Geophysical methods: (i)

In situ soil testing in excavations: (i)

Regional geological mapping.

(ii) Detailed geological mapping excavations and outcrops.

Direct shear tests.

(ii) Plate bearing tests.

Geological studies: (i)

(b)

(i)

In situ testing in excavations and galleries:

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7.1.2. LABORATORY GEOTECHNICAL TESTING METHODS For civil engineering purposes laboratory testing provides the means of identifying and classifying soil and rock properties. Listed are some of the commonly considered laboratory tests. Reference should be made to the relevant Australian Standard or appropriate test method for such requirements as sample condition and size. (a)

(ii) Triaxial compression tests. (iii) Direct shear tests. (iv) California bearing ratio. (h)

Crushing tests.

(iii) Geological type.

(iii) Point load strength test.

(iv) Rock defects and weathering.

(iv) Los Angeles value.

and

(v) Deval attrition.

pertinent

Classification—soil/water properties:

(vi) Polishing of aggregates. (i)

In situ/natural moisture content.

Chemical tests: (i)

pH.

(ii) Liquid, plastic and shrinkage limits.

(ii) Cation exchange capacity.

(iii) Plasticity and liquidity indices.

(iii) Individual exchangeable cations.

(iv) Linear shrinkage.

(iv) Soluble salts content.

(v) Dispersion tests.

(v) Sulfate content.

(vi) Permeability tests.

(vi) Organic matter content.

Material density tests:

(vii) Potential reactivity of aggregates.

In situ/natural density.

(viii) Resistivity tests. (j)

(iii) Dry density/moisture content relation of a soil. (v) Maximum and minimum density of sands. Particle size and shape tests: (i)

Sieve and hydrometer analysis.

(ii) Aggregate shape, flakiness index and angularity.

Mineralogical tests: (i)

Petrographic examination.

(ii) X-ray diffraction.

(iv) Aggregate bulk density and unit mass.

290

Aggregate strength and durability tests: (i)

Consistency, structure and particle size.

(ii) Particle density.

1.

Unconfined compression test.

(ii) Soundness.

(i)

(e)

Soil strength tests:

(ii) Colour, inclusions and accessory materials.

(i)

(d)

(iii) Free swell. (g)

Both disturbed and undisturbed samples may be obtained for laboratory testing. Generally the laboratory test method will indicate the type of test sample required.

(v) Similar characteristics information. (c)

Consolidation/oedometer tests.

(ii) Soil-water suction.

(i)

Visual examination: (i)

Soil deformation characteristics: (i)

Sample disturbance: (i)

(b)

(f)

1

(k)

Miscellaneous tests.

The tests listed above are either standard or well established investigation methods. The list is not intended to be exhaustive, and in any site investigation consideration should be given to the design or use of special tests suited to the problems of the site or relevant to other requirements such as road or rail engineering.

From Appendix C of Australian Standard 1726-1993, by permission.

Field Geologists’ Manual

ENGINEERING GEOLOGY

7.2.1. PHYSICAL PROPERTIES FOR UNWEATHERED ROCKS Rock type

Identification

Uniaxial compressive strength (MPa) Range

Clastic material Conglomerate, Gila Dacite tuff, welded Diabase Diorite Dolomite ,, ,, ,, Granite, biotite ,, ,, Granodiorite ,, , altered Gypsum Hematite, crystalline Hornfels Limestone ,, , arenaceous ,, , bleached ,, , breccia ,, , jasperoidal ,, , mural ,, , siliceous ,, , silicified ,, , ,, ,, , ,, Magnetite, massive ,, , ,, Marble Meta-arkose, schistose Monzonite, ext. altered ,, , quartz ,, , ,, ,, , ,, , altered ,, , ,, , porphyritic Porphyry, altered, silicified ,, , extremely altered ,, , granite ,, , granodiorite, alt. ,, , quartz monzonite ,, ,, ,, ,, ,, ,, , alt. ,, , rhyolitic 1.

26A 25H 10H 10B OD 1A 1B 1C 1D OA 12B 16A 16B 4A 5H 5D OB 15N 15G 7A 15C 19A 14B 14A 15D 16J 5A 9B OC 5C 6C 25A 25B 25E 5G 21B 15B 14D 16C 10D 25C 25D 9A

From: White, C G, 1969. A rock drillability index. Quart. Colo. Sch. Mines, 64, (2), by permission.

Field Geologists’ Manual

Average 2

69.1–126.2 UN3 6.7–20.3 144.4–168.6 212.4–229.0 56.6–96.8 42.5–60.8 42.3–72.5 80.0–120.8 142.2–160.5 76.1–100.8 148.9–198.1 18.1–25.9 28.5–34.9 181.7–249.9 304.4–341.4 41.4–48.6 39.0–57.7 73.8–130.7 97.2–125.9 UN 93.8–119.1 69.6–132.7 55.8–116.7 UN 53.6–106.6 59.2–77.8 239.7–327.8 54.4–73.2 98.1–103.02 15.5–21.2 53.4–144.3 106.7–130.0 72.0–114.9 125.5–170.2 132.4–196.2 7.4–28.3 65.2–91.7 38.3–82.5 70.5–100.5 65.0–118.7 56.8–101.4 104.7–195.5

89.8 UN 12.9 158.3 221.6 69.3 49.5 57.6 92.5 148.5 88.8 179.5 21.2 32.4 235.5 327.0 45.2 46.1 105.3 110.5 UN 101.2 91.5 86.1 UN 74.3 75.1 284.6 61.5 98.1 17.9 94.8 116.0 97.3 154.4 159.5 18.2 76.0 66.4 86.0 98.0 72.9 149.4

Young’s modulus GPa

Scleroscope hardness

26.2 UN 3.4 40.7 38.6 27.6 14.5 15.2 26.9 39.3 22.1 26.9 5.5 17.9 50.3 56.5 11.0 9.7 24.8 24.1 UN 32.4 22.1 25.5 UN 24.1 16.5 59.3 11.7 20.7 3.4 26.9 23.4 22.8 33.8 24.8 6.2 20.0 15.2 29.0 20.7 15.9 33.8

77 — 17 70 78 38 36 33 39 76 59 72 27 6 67 79 14 30 46 42 UN 41 42 37 85 49 42 50 30 36 6 50 67 61 61 76 17 65 42 55 56 59 81

1

Schmidt impact value 66 33 35 60 65 58 53 53 61 62 54 65 36 42 60 65 39 56 61 61 43 55 59 54 61 60 58 60 44 48 31 59 68 61 60 58 39 61 55 51 62 58 62

2. Values based on a limited number of tests. 3. UN Rock unsuitable for preparation of test specimen.

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ENGINEERING GEOLOGY

Rock type

Potash ,, Pyrite, massive Quartzite ,, ,, ,, ,, ,, ,, ,, , impure Rhyolite ,, , ext. alt. Salt ,, Sandstone ,, ,, Schist ,, ,, , altered ,, ,, ,, , brecciated ,, , chlorite, cummingtonite Shale ,, , altered ,, , oil Siltstone ,, ,, Sphalerite, massive, pyritic Trona Tuff

Identification

OB 3B 12D 5B 10C 12A 14C 16D 16E 28A 5E 15L 15H 2A 3A 15A 20B 29A 8B 8C 10E 10G 10A 13B 15K 16G 11B 14G 20A 20E 12E 11A 27A

Uniaxial compressive strength (MPa) Range 19.0–25.2 21.9–31.2 63.2–107.9 122.6–158.6 UN 148.0–215.2 80.7–196.5 70.7–129.0 58.7–97.6 236.8–270.62 168.4–262.12 64.3–82.52 UN 28.0–32.1 30.3–35.0 15.4–26.0 86.9–119.1 19.4–30.1 135.0–263.9 90.4–189.4 80.9–148.0 UN 32.7–70.6 19.7–65.7 57.7–113.6 33.4–50.8 23.4–29.2 44.3–110.1 79.8–122.4 101.8–119.6 57.4–110.2 22.5–39.6 114.4–170.4

Average 21.3 26.8 92.0 140.2 UN 181.5 125.7 90.1 73.5 249.7 200.4 73.7 UN 30.0 32.5 20.6 98.8 25.6 177.9 131.0 106.1 UN 48.1 43.3 75.8 40.5 26.4 64.1 98.5 110.0 74.3 31.0 151.4

Young’s modulus 4.1 0.7 33.1 35.2 UN 36.5 20.7 30.3 17.9 34.5 42.1 16.5 UN 6.9 3.4 4.1 21.4 4.1 37.9 26.2 22.1 UN 15.9 20.7 20.0 11.0 2.8 11.7 17.2 22.1 22.1 12.4 25.5

Scleroscope hardness

Schmidt impact value

4 4 48 83 72 76 67 44 79 71 56 62 27 4 4 25 50 15 77 61 46 35 45 54 53 24 19 31 40 45 35 21 55

20 19 62 62 51 59 59 59 56 68 57 61 43 24 24 45 59 42 67 64 56 39 42 52 53 38 39 48 53 57 52 47 64

S.I. equivalents calculated from Imperial System values using 103 psi = 6.894 76 MPa. For soft rocks the point load test results are too variable for tabulation.

292

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Field Geologists’ Manual

Excluding chalk and coral rock.

— — — — — — 17 48 29 — 4 — 10 12 —

Determined by the resonant bar velocity method.

— — — — — — 76 62 83 — 33 — 50 52 —

5.

28 14 31 14 17 8 8 12 3 12 3 8 4 2 8

Tangent modulus of elasticity at the midstrength point.

51 46 55 50 26 21 27 46 36 23 33 44 25 29 34

+50 per cent of tests — — 34–38 — — 14–21 14–21 — — — — — 4–7 — —

4.

— — — — — — 28 — — — — — 7 — —

Min.

4

Dynamic modulus of elasticity (103MPa) Max. Min. +50 per cent of tests 104 46 — 85 41 — 96 70 — 42 25 28–34 85 22 — 104 24 48–69 82 10 — 105 23 69–90 97 8 — — — — 48 10 — — — — 55 6 — 68 10 10–17 64 7 —

Number of petrographically distinct groups tested in uniaxial compression. Fewer groups were tested for other properties listed.

— — — — — — 56 — — — — — 19 — —

Max.

Static modulus of elasticity3 (103MPa) Max. Min.

3.

210 81 160 155 62 153 159 114 37 46 72 145 33 75 34

+50 per cent of tests — — 276–345 172–241 — 172–241 172–241 — 138–207 207–241 69–138 — — 69–138 —

Modulus of rupture (MPa)

2.

516 359 357 333 359 251 294 314 259 238 194 629 235 231 316

Min.

Tensile strength (MPa) Max. Min.

From Obert, I and Duval, W I, 1967. Rock Mechanics and the Design of Structures in Rock (John Wiley: New York), by permission. Converted to S.I. units 3 using 10 psi = 6.894 76 MPa.

13 9 10 11 10 15 17 11 46 8 15 11 48 18 8

Amphibolite Basalt Diabase Diorite Dolomite Gneiss Granite Greenstone Limestone5 Marble Marlstone Quartzite Sandstone Shale Siltstone

Max.

Compressive strength (MPa)

1.

Number of test groups2

Rock type

1

7.2.2. STATIC MECHANICAL PROPERTIES OF UNWEATHERED ROCKS

ENGINEERING GEOLOGY

293

ENGINEERING GEOLOGY

7.3.1. RECOMMENDED ORDER OF DESCRIPTION OF ROCK 1 PROPERTIES (a)

Composition of rock material: (i)

(b)

Rock name.

(i)

(ii) Grain size.

Strength.

(ii) Weathering.

(iii) Texture and fabric.

(c)

(iv) Colour.

1.

Condition of rock material:

Rock mass properties: (i)

From clause A3.2 of Australian Standard 1726-1993, by permission.

Structure of rock.

(ii) Defects – type, orientation, spacing, roughness, waviness, continuity. (iii) Weathering (of the rock mass).

7.3.2. ROCK WEATHERING CLASSIFICATION Term Residual soil

Symbol RS

Extremely weathered rock

XW

Distinctly weathered rock

DW

Slightly weathered rock Fresh rock

SW FR

1.

1

Definition Soil developed on extremely weathered rock; the mass structure and substance fabric are no longer evident; there is a large change in volume but the soil has not been significantly transported. Rock is weathered to such an extent that it has ‘soil’ properties, ie it either disintegrates or can be remoulded, in water. Rock strength usually changed by weathering. The rock may be highly discoloured, usually by iron staining. Porosity may be increased by leaching, or may be decreased due to deposition of weathering products in pores. Rock is slightly discoloured but shows little or no change of strength from fresh rock. Rock shows no sign of decomposition or staining.

From Table A9 of Australian Standard 1726-1993, by permission.

7.3.3. ROCK STRENGTH CLASSES Term

EL VL

Point load index (MPa) Is50 ≤ 0.03 > 0.03 ≤ 0.1

Low

L

>0.1 ≤ 0.3

Medium

M

>0.3

≤ 1.0

High

H

>1

≤3

Very high

VH

>3

≤ 10

Extremely high

EH

>10

Extremely low Very low

Letter symbol

1

Field guide to strength Easily remoulded by hand to a material with soil properties. Material crumbles under firm blows with sharp end of pick; can be peeled with knife; too hard to cut a triaxial sample by hand. Pieces up to 3 cm thick can be broken by finger pressure. Easily scored with a knife; indentations 1 mm to 3 mm show in the specimen with firm blows of the pick point; has dull sound under hammer. A piece of core 150 mm long by 50 mm diameter may be broken by hand. Sharp edges of core may be friable and break during handling. Readily scored with a knife; a piece of core 150 mm long by 50 mm diameter can be broken by hand with difficulty. A piece of core 150 mm long by 50 mm diameter cannot be broken by hand but can be broken by a pick with a single firm blow; rock rings under hammer. Hand specimen breaks with pick after more than one blow; rock rings under hammer. Specimen requires many blows with geological pick to break through intact material; rock rings under hammer.

Note that although relationships between Unconfined Compression Strength (UCS) and Point Load Index (PLI) exist, they do vary with rock types and the degree of weathering. A ratio of UCS/PLI of 24 has been used, but much lower ratios (as low as ten) can occur. 1.

294

From Table A8 of Australian Standard 1726-1993, by permission.

Field Geologists’ Manual

ENGINEERING GEOLOGY

7.3.4. BULKING FACTORS FOR EXPANSION OF COMMON ROCK MATERIALS

Material Unconsolidated sediments Wet sand Dry sand Wet gravel Dry gravel Wet clayey gravel Clay Clayey soil

Density (g/cm3) In place After excavation

% Expansion

1.95 1.60 2.0 1.8 1.92 1.86 1.76

1.56 1.28 1.60 1.4 1.28 1.49 1.41

20-30 20-30 20-30 20-30 50 20-30 20-30

Rocks Basalt Dolomite Gneiss Granite Limestone Quartz Sandstone Slate

3.0 2.56 2.69 2.72 2.69 2.64 2.42 2.80

1.72 1.73 1.54 1.55 1.54 1.51 1.38 1.52

75 50 75 75 75 75 75 85

Ores Bauxite (Weipa) Iron ore (Hamesley hematite) Range Iron ore (Hamersley hematite) Average Iron ore (Mt Whaleback - Brockman type) Iron ore (Mt Whaleback - Marra Mamba) Iron ore (Pilbara-limonite deposits) Copper (Bougainville porphyry ore) Lead-zinc (Broken Hill) Nickel (Kambalda massive sulphides) Uranium (Mary Kathleen)

1.4 4.21-4.45 4.3 3.85 2.8 2.5 2.6 3.5 3.6 4.1

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7.3.5. DISCONTINUITY SPACING Term Extremely wide Very wide Wide Moderately wide Moderately narrow Narrow Very narrow

1

Spacing >2m 600 mm-2 m 200-600 mm 60-200 mm 20-60 mm 6-20 mm < 6 mm

7.3.6 APERTURE OF DISCONTINUITY SURFACES Term Wide Moderately wide Moderately narrow Narrow Very narrow Extremely narrow Tight 1.

296

1

Aperture (discontinuities) Thickness (veins, faults) > 200 mm 60-200 mm 20-60 mm 6-20 mm 2-6 mm > 0-2 mm Zero

From Anon., 1977. A description of rock masses for engineering purposes. Report by the Geological Society Engineering Group working party, Q J Eng Geol, 10: 356-410, by permission.

Field Geologists’ Manual

Field Geologists’ Manual

Specific

General

Extent

34

Physical description

1

Engineering properties

Term

Foliation Cleavage

Discontinuous microfractures may be present near parallel to the layering

May occur in a zone continuous through several different rock substance types

Usually governed by the thickness and lateral extent of the rock substance or mass containing the defect

Where not uniformly developed, these structures represent defects in the rock mass, ie as individual layers or layered zones

Deformation modules usually higher for β = 0O than β = 90O

Tensile strength usually max. when β = 0 min. when β = 90O O

Compressive Strengths min. when β = 30O to 45O O O Initial shear usually max. when β = 0 and 90

Where uniformly developed in a rock substance any of these types of structure render that rock substance anisotropic in its behaviour under stress

Generally no microfractures

Arrangement in layers of mineral grains of similar sizes or composition, and/ or arrangement of elongated or tabular minerals near parallel to one another and/ or to the layers

Bedding

2

Layering (Layer)

Rock properties, very fissile rock mass When excavated forms GRAVEL. (generally GP)

Joints tightly closed cemented, but cements (usually chlorite or calcite) are weaker than the rock substance SOIL properties, GRAVEL (GP, GM or GC)

Joints not cemented but either coated with soil substance or are open, filled with air, water or both

TYPE ‘R’ ranging to TYPE ‘S’

Zone with roughly parallel planar boundaries of rock material intersected by closely spaced generally (<50 mm) joints and/ or microscopic fracture (cleavage) planes. The joints are at small angles to the zone boundaries; they are usually slightly curved and divide the mass into unit blocks of lenticular or wedge shape; their surfaces are smooth or slickensided

Sheared zone

SOIL properties either cohesive or non-cohesive Usually shows planar anisotropy; lowest shear strength in direction of slickensides in plane parallel in boundaries

Zone with roughly parallel planar boundaries, composed of disoriented, usually angular fragments of the host rock substance. The fragments may be of clay, silt, sand or gravel sizes, or mixtures of any of these. Some minerals may be altered or decomposed, but this is not necessarily so. Boundaries commonly slickensided

Crushed seam/ zone

Extremely decomposed (XD) seam has SOIL properties usually cohesive but may be non-cohesive Mostly very compact except when soluble minerals removed Slightly to highly decomposed substances ROCK properties but usually lower strengths than the fresh rock substances

Zone of any shape but commonly with roughly parallel planar boundaries in which the rock material is discoloured and usually weakened. The boundaries with fresh rock are usually gradational. Geological structures in the fresh rock are usually preserved in the decomposed rock. ‘Weathered’ and ‘altered’ are more specific terms

Decomposed seam/ zone

Weak seams or zones

SOIL properties usually cohesive (CL or CH) but may be non-cohesive

Zone of any shape but commonly with roughly parallel planar boundaries composed of soil substance. May show layering roughly parallel to the zone boundaries. Geological structures in the adjacent rock do not continue into the infill substance

Infilled seam/ zone

From 10 mm to 50 m or more, depends on origin

Generally large (50 m to many km)

Weathered zones related to present or past land surface limited extent. Altered zones occur at any depth

Usually small limited to mechanically weathered zone. Can be great in rocks subject to solution

Engineering properties commonly different from place to place especially where the defect passes through several different rock substance types

C cohesion of coating/cement/ Both types show extreme planar anisotropy. Lowest wall-rock shear strength in direction of slickensides, in plane φ friction angle or coating/ parallel to boundaries cement/ wall- rock / angle of roughness of surface Kn normal stiffness Ks tangential stiffness

PARAMETERS

Tensile strength low/ zero Sliding resistance depends upon properties of coatings or cement and condition of surfaces

A discontinuity or crack, planar, curved or irregular, across which the rock usually was little tensile strength. The joint may be open (filled with air or water) or filled by soil substance or by rock substance which acts as a cement, joint surfaces may be rough, smooth, or slickensided

Joint

Fractures and fractured zones

1

7.4.1. COMMON DEFECTS IN ROCK MASS

ENGINEERING GEOLOGY

297

298

Map symbols (horiz, vert, dipping)

6

Terms not used (for these defects)

5

Associated description, etc

Description required

Origin (usually controls extent)

Shearing during folding or faulting Consolidation, compaction

Fabric description, and spacing and extent of microfractures

Viscous flow Crystal growth at high pressures and temperatures Shearing under high confining pressure Faulting

Degree of decomposition

Decomposition of minerals, removal or rupture of cement, due to circulation of mineralized waters usually along joints, sheared zones or crushed zones

Cohesive soil carried into open joint or cavity as a suspension in water Non- cohesive soil falls or washes in

Shear-, shatter-, shattered-, crush-, broken-, blocky-zone; slip, shear, mylonite, gouge, breccia, fault- breccia, crush breccia, pug. The terms ‘fault’ or ‘fault- zone’ are only used in a genetic or general sense and must be qualified by the use of the defined terms given above. ‘Mylonite’ is rock substance with intense planar foliation, developed due to shearing at great depth beneath the earth’s crust

Fissure, crack, slip, shear, break, fracture (except in general sense for joints, faults cleavage planes)

Rotten, disintegrated, softened, soft (unless in defined sense for clay)

Attitude of zone. Classify as weathered or altered if possible and determine origin and defects or defects influencing decomposition

Vein, fissure, pug, gouge

Attitude of zone. Type of defect which is infilled, origin of infill substance

Standard description of soil or rock substance

Zone width, shape and extent

Failure by large movement within narrow zone Generally formed at shallow depth (< 3000 m)

Attitude of zone. Direction of slickensides and amount, direction, and sense of displacement. Type of fault. History of past movements. Any modern activity. Likelihood of future movements. The terms ‘major’ and ‘minor’ fault are defined whenever used. The definitions are made on the basis of (a) width and nature of the fault materials, (b) significance to the project

Pattern of joints or micro-fractures and resulting shape and size of unit blocks. Standard description of joints

Shear failure by small displacements along a large number of near-parallel intersecting planes. The different strengths of Types R and S are usually due to (a) different depths of rock cover at the time of faulting or (b) later cementation or (c) later mechanical weathering

Spacing, attitude of joint and of slickensides

Shape, aperture, surface condition, coating, filling, extent

Shearing, extension or torsion failure, arising from faulting, folding, relief of pressure, shrinkage due to cooling or loss of fluid

Allocate to set, determine origin type

Attitude of planes and of any linear structure, extent

Strata, stratification, schistosity, gneissosity, micro-fissuring

Graded, discordant, slumpbedding; other primary structures; Facing, Attitudes Lineations

Ease of splitting and nature of fracture faces

Bed thickness, grain types and sizes

Deposition in layers

ENGINEERING GEOLOGY

Field Geologists’ Manual

ENGINEERING GEOLOGY

7.4.1. NOTES 1.

2.

3.

4.

5.

6. 7. 8.

The actual defect is described, not the process which formed or may have formed it, eg, ‘sheared zone’, not ‘zone of shearing’: the latter suggests a currently active process. The terms ‘layering’, ‘bedding’, etc are used as the main headings on this portion of the Table allowing them to refer to both rock substances and masses. These notes refer to the engineering properties of the defect type, not those of the rock mass containing the defect. In general, each rock defect is more permeable than the material in which it occurs, and the defect strength becomes lower with increase in water content/pressure. Such terms as ‘strong’, ‘strongly’, or ‘weakly’, are never used to indicate the degree of development of a defect or group of defects. Geological map symbols conform where possible to symbols used on geological maps. Thickness, openness—measured in millimetres normal to plane of the discontinuity. Roughness—a measure of the inherent surface unevenness and waviness of the discontinuity relative to its mean plane, as follows:

10. Persistence – the areal extent of defect. Give trace lengths, in metres. 11. Spacing – measure of the spacing of defects. Measure mean and range of spacings for each set where possible (do not use descriptive terms). Alternative criteria may be used for quantitative description of the fracture state of rock cores such as the solid core recovery, fracture log, and rock quality designation (RQD). The simplest measure is the solid core recovery ratio, particularly when contrasted with the total core recovery (which includes fragmented cores). A fracture log is a count of the number of natural fractures present over an arbitrary length. RQD is often used as a quantitative measure of the rock recovered as lengths of 100 mm or more. Only core lengths determined by geological fractures should be measured. If the core is broken by handling or by the drilling process (ie the fracture surfaces are fresh, irregular breaks rather than natural joint surfaces) the fresh broken pieces are fitted together and counted as one piece. The terms used in this Note are defined as follows: (a) Fracture log or frequency (F) is the number of natural fractures present in a unit length of core (usually 1 m). (b) Recovery ratio or total core recovery (R) is the ratio of total length of core recovered to length or core run drilled (usually 1.5 m or 3.0 m) expressed as a percentage.

Roughness Class I II III IV V VI VII VIII IX 9.

Description Rough or irregular, stepped Smooth, stepped Slickensided, stepped Rough or irregular, undulating Smooth, undulating Slickensided, undulating Rough or irregular, planar Smooth, planar Slickensided, planar

Coating or infilling: Clean –

no visible coating or infilling.

Stain –

no visible coating or infilling but surfaces are discoloured by mineral staining.

Veneer –

a visible coating or infilling of soil or mineral substance but usually unable to be measured (less than 1 mm). If discontinuous over the plane, patchy veneer.

Coating –

a visible coating or infilling of soil or mineral substance, greater than 1 mm thick. Describe composition and thickness.

Field Geologists’ Manual

(c) Rock quality designation (RQD) is the ratio of length of rock core recovered in pieces of 100 mm or longer to length of core run drilled (usually 1.5 m or 3.0 m) expressed as a percentage. 12. Defect spacing in three dimensions. The spacing of defects may be described with reference to the size and shape of rock blocks bounded by defects, as follows: Term Description Blocky Equidimensional Tabular Thickness much less than length or width Columnar Height much greater than cross section

1.

From Table A10 of Australian Standard 1726-1993, by permission.

299

300 extremely rapid

1 ft/5 yr-0.06 m/yr extremely slow

very slow

5 ft/mo-1.5 m/mo slow 5 ft/yr-1.5 m/yr

moderate

5 ft/d-1.5 m/d

rapid

1 ft/min-0.3 m/min

very rapid

10 ft/s-3 m/s

FLANK - The side of the landslide. CROWN - The material that is still in place, practically undisplaced and adjacent to the highest parts of the main scarp. ORIGINAL GROUND SURFACE - The slope that existed before the movement which is being considered took place. If this is the surface of an older landslide, that fact should be stated. LEFT AND RIGHT - Compass directions are preferable in describing a slide, but if right and left are used they refer to the slide as viewed from the crown. SURFACE OF SEPARATION - The surface separating displaced material from stable material but not known to have been a surface on which failure occurred. DISPLACED MATERIAL - The material that has moved away from its original position on the slope. It may be in a deformed or undeformed state. ZONE OF DEPLETION - The area within which the displaced material lies below the original ground surface. ZONE OF ACCUMULATION - The area within which the displaced material lies above the original ground surface.

-109

-108

-107

-10

6

-105

-10

4

-103

-102

-101

1

10

102

ft/sec

RATE OF MOVEMENT SCALE Approximate ranges of rates of movement are according to the scale below

1. Modified from Figure 2.1 in Varnes, DJ, 1978. Slope movement and types and processes, in Landslides: Analysis and Control, Transportation Research Board, National Academy of Sciences, Washington DC, Special Report 176.

NOMENCLATURE MAIN SCARP - A steep surface on the undisturbed ground around the periphery of the slide, caused by the movement of slide material away from undisturbed ground. The projection of the scarp surface under the displaced material becomes the surface of rupture. MINOR SCARP - A steep surface on the displaced material produced by differential movements within the sliding mass. HEAD - The upper parts of the slide material along the contact between the displaced material and the main scarp. TOP - The highest point of contact between the displaced material and the main scarp. TOE OF SURFACE OF RUPTURE - The intersection (sometimes buried) between the lower part of the surface of rupture and the original ground surface. TOE - The margin of displaced material most distant from the main scarp. TIP - The point on the toe most distant from the top of the slide. FOOT - That portion of the displaced material that lies downslope from the toe of the surface of rupture. MAIN BODY - That part of the displaced Material that overlies the surface of rupture between the main scarp and toe of the surface of rupture.

SLUMP-EARTH FLOW

1

7.4.2. CLASSIFICATION OF LANDSLIDES

ENGINEERING GEOLOGY

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ENGINEERING GEOLOGY

Field Geologists’ Manual

301

302

(DOMINANT)

Movement is by a combination of one or more of the five principal types of movement described above. Many landslides are complex, although one type of movement generally dominates over the others at certain areas within a slide or at a particular time.

VI. COMPLEX

Includes spatially continuous deformation and surficial as well as deep creep. Involves extremely slow and generally nonaccelerating differential movements among relatively intact units. Movements may 1. Be along many shear surfaces that are apparently not connected; 2. Result in folding, bending, or bulging; or 3. Roughly simulate those of viscous fluid& in distribution of velocities.

V. FLOWS

TYPE OF MOVEMENT

1 km 0.6 mile

3.

1.8 km

(1.1 m Debris flow or slide iles)

Rock Fall

EXAMPLES ROCK FALL-DEBRIS FLOW (ROCK-FALL AVALANCHE), Extremely rapid

2.

1.

BEDROCK

1

3 2

e

d

c

b

a

ROCK SLIDE-ROCK FALL

1640ft

500m

Note: Sackung or gravitational sagging is illustrated by 1, 2, and 3.

Gravity downslope movement of clayey rocks and coal on the margin of a sedimentary basin

SLUMP AND TOPPLE

100m 328ft

4.

ENGINEERING GEOLOGY

Field Geologists’ Manual

(DOMINANT)

Field Geologists’ Manual

IV. LATERAL SPREADS

B. TRANSLATIONAL

A. ROTATIONAL

III. SLIDES

Bedrock

DEBRIS SLIDE

DEBRIS SLUMP

Clean sand

Firm clayey gravel

Firm clay Soft clay with water-bearing silt and sand layers

EARTH LATERAL SPREAD

EARTH BLOCK SLIDE

Clay

EARTH SLUMP

EARTH TOPPLE

DEBRIS TOPPLE

II. TOPPLES

Clayey gravel

EARTH FALL

EARTH

DEBRIS FALL

DEBRIS

I. FALLS

TYPE OF MOVEMENT

ENGINEERING GEOLOGY

303

304

(DOMINANT)

VI. COMPLEX

IN SOIL Movement within the displaced mass is such that the form taken by the moving material or the apparent distribution of velocities and displacements resemble those of viscous fluids. Slip surfaces within moving material are usually not visible or are short-lived. Boundary between moving mass and material in place may be a sharp surface of differential movement or a zone of distributed shear. Movement ranges from extremely rapid to extremely slow.

V. FLOWS

TYPE OF MOVEMENT

CAMBERING AND VALLEY BULGING

DEBRIS SLIDE

BLOCK STREAM

DEBRIS AVALANCHE, very rapid to extremely rapid

DEBRIS FLOW, very rapid

DEBRIS

NOTE: Most, if not all slow earth flows in cohesive materials are complex in that finite shear occurs along the flanks and basal surface, although the distribution of velocities within the displaced material may indicate plastic flow.

LOESS FLOW (dry, caused by earthquakes), extremely rapid. Also moist or wet DRY SAND FLOW, rapid to very rapid

RAPID EARTH FLOW (QUICK CLAY FLOW), very rapid

EARTH FLOW very slow to rapid

WET SAND OR SILT FLOW, rapid to very rapid

SLUMP - EARTH FLOW

SOIL CREEP, extremely slow

SOLIFLUCTION

EARTH

ENGINEERING GEOLOGY

Field Geologists’ Manual

ENGINEERING GEOLOGY

7.5.1 ORDER OF DESCRIPTION OF SOILS (a)

Composition of soil (disturbed or undisturbed state). The description should include the following: (i)

(ii) Consistency (undisturbed state only). (c)

Classification group symbol (use block letters) (see 7.5.1.).

(i)

(ii) Soil name (use block letters). (d)

(iv) Colour of soil.

NOTES:

NOTE: Precise description of properties shown in italics is frequently impracticable. Conditions of soil. The following conditions are important: (disturbed

Soil origin, eg FILL, ALLUVIUM, COLLUVIUM, SLOPEWASH, RESIDUAL SOIL.

(ii) Other matters believed to be significant.

(vi) Other minor soil components – name, estimated proportion, plasticity, or particle characteristics, colour.

or

1.

Field Geologists’ Manual

Additional observations. Certain additional observations may sometimes be required, such as the following: (i)

(v) Secondary soil components – name, estimated proportion, plasticity or particle characteristics, colour.

Moisture condition undisturbed state).

Zoning.

(iii) Cementing.

(iii) Plasticity or particle characteristics of soil.

(i)

Structure of soil. In the undisturbed state, the following aspects should be noted: (ii) Defects.

NOTE: The presence of fill should be indicated at this stage.

(b)

1

1.

Soil origin cannot generally be deduced on the basis of material appearance and properties alone, but requires further geological evidence and field observation.

2.

Soil origin, eg ‘FILL’ and ‘TOPSOIL’ is emphasised by use of BLOCK LETTERS.

From Australian Standard 1726-1993, by permission.

305

SANDS (more than half of coarse fraction is smaller than 2.36 mm)

GRAVELS (more than half of coarse fraction is larger than 2.36 mm)

COBBLES

BOULDERS

Major divisions

COARSE GRAINED SOILS (more than half of material less than 63 mm is larger than 0.075 mm)

306

fine

0.2

0.6

2.36

6

20

0.075

medium

coarse

fine

medium

coarse

63

200

Particle size, mm

‘Dirty’ materials with excess of non-plastic fines, zero to medium dry strength

Silty gravels, gravelsand-silt mixtures

Clayey gravels, gravelsand-clay mixtures

GM

GC

SC

SM

SP

SW

‘Dirty’ materials with excess of non-plastic fines, zero to medium dry strength

Silty sands, sand-silt mixtures

‘Dirty’ materials with excess of plastic fines, medium to high dry strength

Predominantly one size or range of sizes with some intermediate sizes missing, not enough fines to bind coarse grains, no dry strength

Poorly graded sands and gravelly sands; little or no fines, uniform sands

Clayey sands, sandclay mixtures

Wide range in grain size and substantial amounts of all intermediate sizes, not enough fines to bind coarse grains, no dry strength

Well graded sands, gravelly sands, little or no fines

‘Dirty’ materials with excess of plastic fines, medium to high dry strength

Predominantly one size or range of sizes with some intermediate sizes missing, not enough fines to bind coarse grains, no dry strength

GP

Poorly graded gravels and gravel-sand mixtures, little or no fines, uniform gravels

Field identification Sand and Gravels

Wide range in grain size and substantial amounts of all intermediate sizes, not enough fines to bind coarse grains, no dry strength

Typical names

Well-graded gravels, gravel-sand mixtures, little or no fines

GW

Group symbol

passing 63 mm for classification of fractions according to the criteria given in ‘Major Divisions’

12-50

12-50

0-5

0-5

12-50

12-50

0-5

0-5

% (2) < 0.075 mm

Above ‘A’ line and Ip >7

Below ‘A’ line or Ip <4

Below ‘A’ line and Ip >7

Below ‘A’ line or Ip <4

PLASTICITY OF FINE FRACTION

D60 D10

>6

>4

Cu=

Fails to comply with above

Fails to comply with above

Cs=

Laboratory classification

between 1 and 3

between 1 and 3

2

(D30) D10 D60

1

7.5.2. DESCRIPTION, IDENTIFICATION AND CLASSIFICATION OF SOILS

2. Borderline classifications occur when the percentage of fines (fraction smaller than 0.75 mm size) is greater than 5% and less than 12%. Borderline classifications require the use of dual symbols eg SP-SM, GW-GC

1. Identify lines by the method given for fine grained soils.

NOTES

ENGINEERING GEOLOGY

Field Geologists’ Manual

Field Geologists’ Manual

FINE GRAINED SOILS (more than half of material less than 63 mm is smaller than 0.075 mm)

Pt

OH

CH

MH

OL

CL, CI

ML

Low to medium

High

Low to medium

Low

Medium

None

Silty fine sands and silts have about the same slight dry strength, but can be distinguished by the feel when powdering the dried specimen. Fine sand feels gritty whereas a typical silt has the smooth feel of flour.

A typical inorganic silt possesses only very slight dry strength.

After removing particles larger than 0.2 mm size, mould a pat of soil to the consistency of putty, adding water if necessary. Allow the pat to dry completely by oven, sun or air drying, and then test its strength by breaking and crumbling between the fingers. This strength is a measure of the character and quantity of the colloidal fraction contained in the soil. The dry strength increases with increasing plasticity. High dry strength is characteristic for clays of the CH group.

‡

Toughness

Use the gradation curve of material

Below ‘A’ line

Above ‘A’ line

Below ‘A’ line

Below ‘A’ line

Above ‘A’ line

Below ‘A’ line

Effervesces with H2O2

More than 50% passing 0.06 mm

Very fine clean sands give the quickest and most distinct reaction whereas a plastic clay has no reaction. Inorganic silts, such as a typical rock flour, shows a moderately quick reaction.

The rapidity of appearance of water during shaking and of its disappearance during squeezing assist in identifying the character of the fines in a soil.

Place the pat in the open palm of the hand and shake horizontally, striking vigorously against the other hand several times. A positive reaction consists of the appearance of water in the surface of the pat which changes to a livery consistency and becomes glossy. When the sample is squeezed between the fingers, the water and gloss disappear from the surface, the pat stiffens, and finally it cracks or crumbles.

After removing particles larger than 0.2 mm size, prepare a pat of moist soil with a volume of 10 3 cm . Add enough water if necessary to make the soil soft but not sticky.

† Dilatancy (Reaction to shaking)

Identified by colour, odour, spongy feel and generally by fibrous texture

None to very slow

None

High to very high Medium to high

Slow to none

Slow

None to very slow

Low to medium

Low to medium

Medium to high

Quick to slow

None to low

†

Dilatancy

Dry* strength

* Dry strength (Crushing characteristics)

Peat and other highly organic soils

Organic clays of medium to high plasticity, organic silts

Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, clastic silts Inorganic clays of high plasticity, fat clays

Organic silts and organic silty clays of low plasticity

Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, Iean clays

Inorganic silts are very fine sands, rock flour, silty or clayey fine sands or clayey silts with slight plasticity

1. From Table A1 of Australian Standard 1726-1993, by permission.

These procedures are to be performed on the minus 0.2 mm size particles. For field classification purposes, screening is not intended, simply remove by hand the coarse particles that interfere with the tests.

Field identification procedure for fine grained soils or fractures

HIGHLY ORGANIC SOILS

SILTS and CLAYS (liquid limit >50%)

SILTS and CLAYS (liquid limit <50%)

Weakness of the thread at the plastic limit and quick loss of coherence of the lump below the plastic limit indicate either inorganic clay of low plasticity, or materials such as kaolin-type clays and organic clays which occur below the A-line. Highly organic clays have a very weak and spongy feel at the plastic limit.

After the thread crumbles, the pieces should be lumped together with a slight kneading action continued until the lump crumbles. The tougher the thread near the plastic limit and the stiffer the lump when it finally crumbles, the more potent is the colloidal clay fraction in the soil.

soil about 10 cm in size is moulded to the consistency of putty. If too dry, water must be added and if sticky, the specimen should be spread out in a thin layer and allowed to lose some moisture by evaporation. The specimen is then rolled out by hand on a smooth surface or between the palms into a thread about 3 mm in diameter. The thread is then folded and rerolled repeatedly. During this manipulation the moisture content is gradually reduced and the specimen stiffens, finally loses its plasticity, and crumbles when the plastic limit is reached.

3

After removing particles larger than 0.2 mm size, a specimen of

‡ Toughness (Consistency near plastic limit)

I

ENGINEERING GEOLOGY

307

7.5.3. CALCAREOUS SEDIMENTARY ROCK NOMENCLATURE

1

ENGINEERING GEOLOGY

308

NOTES: (1) Non-carbonate constituents are likely to be siliceous apart from local concentrations of mixed heavy minerals. (2) In description the rough proportions of carbonate and non-carbonate constituents should be quoted and details of both the particle minerals and matrix minerals should be included. (3) The preferred lithological nomenclature has been shown in block capitals; alternatives have been given in brackets and these may be substituted in description if the need arises.

(4) Calcareous is suggested as a general term to indicate the presence of unidentified carbonate. Where applicable, when mineral identification is possible calcareous referring to calcite or alternative adjectives such as dolomitic, aragonitic, sideritic etc should be used. 1.

From Clark, A R, and Walker, P F, 1977. A proposed scheme for classification and nomenclature for use in the engineering descriptions of Middle Eastern sedimentary rocks, Geotchnique, 27: 93-99. Field Geologists’ Manual

ENGINEERING GEOLOGY

7.5.4. CONSISTENCY OF SOILS There are two distinct methods of description of this matter: (i)

Essentially cohesive soils. Consistency of essentially cohesive soils may be described in terms of a scale of strength (see Table below). If a mineral cement appears to be present, it is also useful to note whether slaking occurs on immersing the air dry material in water. In the field the undrained shear strength can also be assessed using a pocket penetrometer for firm to very stiff soils or a hand vane for very soft to firm soils. These devices must be used with calibration charts.

(ii) Essentially non-cohesive soils. The consistency of essentially non-cohesive soils is described in

1

terms of the density index, as defined in AS 1289.0. It is not possible to make an assessment of the density index without some form of test on an undisturbed or in situ sample. These soils are inherently difficult to assess, and normally a penetration test procedure (SPT, DCP or CPT) is used in conjunction with published correlation tables. Alternatively, in situ density tests can be conducted in association with minimum and maximum density tests performed in the laboratory. The Table below lists terms applicable to these soils.

1.

From Australian Standard 1726-1993, by permission.

CONSISTENCY TERMS – COHESIVE SOILS Term

Undrained shear strength kPa

Field guide to consistency

Very soft

≤12

Soft

>12

≤25

Can be moulded by light finger pressure

Firm

>25

≤50

Can be moulded by strong finger pressure

Stiff

>50

≤100

Very stiff

>100 ≤200

Cannot be moulded by fingers Can be indented by thumb Can be indented by thumb nail

Hard

>200

Can be indented with difficulty by thumb nail

Exudes between the fingers when squeezed in hand

CONSISTENCY TERMS – NON-COHESIVE SOILS Term

Density index % ≤15

Very loose Loose

>15

≤35

Medium dense

>35

≤65

Dense

>65

≤85

Very dense

>85

7.5.5. SOIL MOISTURE CONTENT This is described by appearance and feel of the soil using one of the following terms: (i) ‘Dry’ (D) –

Cohesive soils; hard and friable or powdery, well dry of plastic limit.

Cohesive soils can be moulded. Granular soils tend to cohere. (iii) ‘Wet’ (W) –

Granular soils; cohesionless and free-running. (ii) ‘Moist’ (M) – Soil feels colour.

cool,

darkened

Soil feels colour.

cool,

darkened

in

Cohesive soils usually weakened and free forms on hands when handling.

in

Granular soils tend to cohere. 1.

Field Geologists’ Manual

1

From Australian Standard 1726-1993, by permission.

309

ENGINEERING GEOLOGY

7.6 DYNAMIC PENETRATION TEST can be performed on soil that is essentially undisturbed by the drilling process.

The most common dynamic penetration test used in boreholes is the ‘standard penetration test’ (SPT). It is usually applied to cohesionless soils, but is also a valuable tool for preliminary site studies in cohesive soil and deeply weathered rock. The penetration tool is a thick-walled splitspoon sampler (Raymond Sampler) 50 mm OD and 35 mm ID. The sampler is attached to the bottom of drilling rods and driven 450 mm into the soil at the bottom of the borehole with a 63.5 kg hammer falling freely through 760 mm. Only the number of blows for the last 300 mm of driving is recorded as the standard penetration resistance N. It is food practise to count the number of blows for every 150 mm of penetration in the full 450 mm of driving. After withdrawal from the borehole the tube is split and the sample examined for laminations or other structural features. A standard procedure for this test is described below. Various suggestions have been made relating to the adjustment of the measured N values to allow for the influence of effective over-burden pressure and the adjustment of measured N values in fine sand beneath the water table, but these adjustments are not universally applicable. When N values are being measured beneath the water table however great care is needed to minimise errors caused by disturbance of granular soils by inflow of water. Any drilling equipment can be used, provided it has a winch and the head can be moved out of the way so that the hammer can operate in line with the drillhole. An automatic trap hammer is shown on page 380 of Australian Drilling Manual (Australian Drilling Industry Training Committee Ltd: Sydney). Hand-held penetrometers are used in soils to a maximum depth of about 4 m – see AS 1289, section 6.3.2 and 6.3.3.

Casing or drilling mud shall be provided for use in soils that will not stand open. Where rotary techniques are used, the drilling bit shall be designed to provide side discharge rather than downward discharge. (b) Sampler rods for driving the sampler, having a stiffness not less than that of an AW rod (see BS 4019, Part 1). For holes deeper than 15 m, steadies shall be used at intervals of 6 m or, alternatively, stiffer rods shall be used. The diameter of the rods shall not exceed 70 mm (NQ rod). (c) Sampler as shown in Figure 1. The drive shoe shall be of hardened steel and shall be replaced or repaired when it becomes dented or distorted sufficiently to affect the test results. The coupling head shall have a check valve with a minimum vent area of 390 mm2 or four 13 mm diameter vent ports, or both. The central section of the sampler is normally of split construction allowing easy removal of the sample. However, a continuous tube conforming to the dimensions of Figure 1 is also acceptable. The sampler may have a core retainer which should be thin and flexible enough to cause minimum interference to the soil entering the sampler. (d) Drive hammer assembly, consisting of a 63.5 ±1 kg mass, a driving head and guide permitting a free fall or 760 ±15 mm. The assembly shall incorporate a self-tripping mechanism so that the hammer is allowed to fall freely without any energy loss due to lifting winch inertia. The striking face of the anvil shall preferably be domed, 3 mm in 100 mm, to prevent off-centre impact between the hammer and anvil. The driving head and guide shall be essentially vertical.

DETERMINATION OF THE PENETRATION RESISTANCE OF A SOIL1 1.

2.

Scope of method. The method describes the procedure for determining the resistance of soils to the penetration of a split-tube sampler, and the obtaining of disturbed samples of the soils for identification purposes (Note 1). Apparatus. The following apparatus is required: (a) Drilling equipment, capable of providing a clean stable hole for insertion of the sampler, and such that the penetration test

1.

310

From AS 1289.6.3.1-1993, by permission.

3.

Procedure. The procedure shall be as follows: (a) Drill a vertical hole of at least 65 mm diameter to the depth at which the test is to be conducted. Clean out the hole using equipment that will ensure that the material to be sampled is not disturbed by the operation. In saturated sands and silts, slowly withdraw the drilling bit or bailer or central plug of hollow flight augers to prevent loosening of the soil around the hole. Maintain a positive hydrostatic head

Field Geologists’ Manual

ENGINEERING GEOLOGY

in the borehole over the natural piezometric pressure at the test location by the use of water, drilling mud or weighted drilling mud, should artesian conditions exist. Casing, when used, shall not be driven below sampling level.

(ii) The penetration resistance in the form of the following examples: (A) for full penetration, the number of blows for each 150 mm penetration and the N value, eg for successive blow counts of 4, 7 and 11 for each 150 mm penetration

For sands below the water table, the use of hollow flight auger or percussion drilling methods is not recommended (see Note 2).

4, 7, 11 N = 18;

(b) (i) Measure the length of the sampler and all drilling subs and driving rods. Attach the sampler, which shall be cleaned at the beginning of each test, to the driving rods and carefully lower it to the bottom of the hole. Make sure that it is freely lowered and that caving of the bore or flow of soil into the casing by more than 50 mm has not taken place by measuring the depth at which the sampler strikes the soil in the bottom of the borehole. Record the depth of the sample tip. If there is evidence that soil is present inside the casing the sampler must be removed from the hole and the casing cleaned out before the sampler is reintroduced. Attach the driving assembly, and drive the sampler with blows of the 63.5 ±1 kg hammer falling 760 ±15 mm.

(B) for a result of four blows for the first 150 mm, 18 blows for next 150 mm and 30 blows for next 15 mm— 4, 18, 30/15 mm; and (C) for a result of 30 blows for the first 80 mm penetration— 30/80 mm. Include the abbreviations RW (rod, weight only caused full penetration), HW (hammer and rod weight only caused full penetration), and HB (hammer bouncing) where appropriate. (b) General information: (i) Date of drilling. (ii) Location of borehole and identifying number of the hole.

(ii) Drive the sampler 450 mm and record the number of blows for each successive 150 mm of penetration. The first 150 mm of penetration is the seating drive. The number of blows for the second and third 150 mm of penetration (ie together from 150 mm to 450 mm) are added, and termed the penetration resistance (N). (iii) If a total of 30 blows causes less than 100 mm penetration at any stage, discontinue the test.

(c)

4.

(iii) Reduced level of ground surface. (iv) Casing size and depth of installation, or presence of drilling mud and depth of test. (v) Information on the water levels in the borehole during testing. (vi) Soil description (or note that sample not recovered).

NOTES ON TEST:

(iv) If there is no measurable penetration or the hammer is bouncing for five consecutive blows, discontinue the test.

1.

Bring the sampler to the surface and dismantle. Place a representative sample of the soil in an airtight container to maintain the sample moisture content and label with project bore number and depth. If more than one soil type is encountered, use a separate container for each soil type.

Interpretation of results. This test gives a value for the penetration resistance of any soil. For the interpretation of N values to give in situ density or strength parameters the reader is referred to current standard texts.

2.

Drilling method. It is known that in clean sands below the water table with the use of hollow spiral flight augers or percussion drilling methods, a ‘running sand’ condition can very easily be created. For this reason, use of this equipment is regarded as ‘non-standard’. However, in situations where alternative equipment is not available, the risk of disturbance to the soil can be reduced by skilled operators. Techniques such as the use of a water or mud head within the casing

Test report. Report the following results and general information as appropriate: (a) Results: (i) The depth at commencement of test.

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311

ENGINEERING GEOLOGY

3.

and the slow extraction of the bailer or auger plug will reduce the potential for problems. Where this type of drilling equipment is used, reporting of the results should specifically draw attention to its use and to the precautions taken.

NOTES: 1.

The split barrel may be larger than 35 mm internal diameter provided that it also incorporated a liner of suitable thickness but not exceeding 2 mm.

Gravelly soils. In gravelly soils it is sometimes found convenient to replace the split tube by a solid cone of 50 mm diameter and 60 degree included angle. The penetration resistance so obtained can differ from that measured with a sample tube, and therefore the use of such a cone should be appropriately reported.

2.

Sample retainers in the driving shoe to prevent loss of sample are permitted, but must not obstruct the passage of the sample into the sampler.

3.

The external corners at A may be rounded such that the tip edge is not less than 1.0 mm wide.

A

Dimensions in millimetres. FIG 1 - Typical split-tube sampler assembly.

312

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Field Geologists’ Manual

2

Clean sands, clean sand and gravel mixtures

1

1.0

-1

10

-2

10

-5

10

K, cm/s

-3

-4

10

Horizontally capillary test

10

Electoosmosis

Poor drainage

-5

10

Falling head - much experience necessary

Polymer grouts

Vacuum well points

Computations from grain size distribution, surface area and porosity

Reliable

-4

10

-6

10

Very fine sands, organic and inorganic silts, mixtures of sand, silt and clay, glacial till, stratified clay deposits, etc

-3

10

1

-6

10

-7

10

-7

10

-8

10

-9

10

Computations from consolidation test

Permeameterfairly reliable- experience necessary

Practically impervious

-9

10

Impervious soils, eg homogeneous clays below zone of weathering

-8

10

Impervious sections of dams

Fine-grained soils, normally ‘impervious’ but modified by effect of vegetation and weathering (in situ) or dry compaction (fill)

K, cm/s

Silicate grouts

10

-2

Direct testing of soil in place, eg field pumping tests-reliable; experience required

Well points

Good drainage

Constant head permeameterreliable

10

10

-1

Pervious sections of dams

1.0

Cement grout

Clean gravel

10

1

From Australian Standard 1726-1981, by permission.

INDIRECT DETERMINATION OF K

DIRECT DETERMINATION OF K

Grouting

Drainage

2

10

10

Earth dams

TYPES OF SOILS

ENGINEERING APPLICATIONS AND PROPERTIES

7.7.1. HYDRAULIC CONDUCTIVITY (PERMEABILITY)

ENGINEERING GEOLOGY

313

314

1.

R O C K S

S E D I M E N T A R Y 2.5 12 45

Loess Aeolian sand Tuff 0.08 20 0.16

fine medium coarse

Gravel, 450 273 150

3.8 14 28

fine medium coarse

Sand,

1.45 1.58 1.48

1.76 1.85 1.93

1.55 1.69 1.73

1.38

0.0025

Silt

0.08

1.49

negligible

negligible

Clay

1.51

1.61

1.76 1.68

2.53

negligible

0.29

Horizontal (m/day)

Dry unit weight (g/ml)

Shale

Claystone

0.2 3.1 negligible

fine medium

Vertical (m/day)

Siltstone

Sandstone,

Repack (m/day)

Coefficient of permeability

2.67 2.66 2.50

2.68 2.71 2.69

2.67 2.66 2.65

2.66

2.67

2.73

2.66

2.65

2.65 2.66

Density of solids

Property

49 45 41

43 39 39

46

42

6

43

35

33 37

Porosity undisturbed (%)

46 38

34 32 28

32 35 34

46

48

43

Porosity repack (%)

27 3 21

7 7 9

8 4 5

28

38

29

13 10

Specific retention (%)

18 38 21

29 24 21

33 32 30

20

6

12

21 27

Specific yield (%)

From Hazel, C R, 1973. Lecture notes on groundwater hydraulics, Australian Water Resources Council 1973, Groundwater School, Adelaide. After USGS Hydrologic Laboratory, by permission.

Wind-laid deposits

Water-laid deposits

Strata

1

7.7.2. SUMMARY OF THE ARITHMETIC MEAN OF HYDRAULIC PROPERTIES FOR ALL ROCK TYPES

ENGINEERING GEOLOGY

Field Geologists’ Manual

Field Geologists’ Manual

Silt Sand Gravel

Washed drift

Schist Slate

METAMORPHIC ROCKS

Limestone Dolomite Peat

Clay Silt Sand Gravel

Till

Weathered granite Weathered gabbro Basalt

Chemical and organic deposits

Ice-laid deposits

IGNEOUS ROCKS

SEDIMENTARY ROCKs

Strata

38 204

0.5 30

Repack (m/day)

0.16 negligible

1.4 0.16 0.008

5.7

1

0.2 14

1

Vertical (m/day)

1.8

Horizontal (m/day)

Coefficient of permeability

1.76

1.50 1.73 2.53

1.94 2.02 0.13

1.38 1.55 1.60

1.78 1.88 1.91

Dry unit weight (g/ml)

2.79 2.94

2.74 3.02 3.07

2.75 2.69 1.54

2.72 2.69 2.68

2.65 2.70 2.69 2.72

Density of solids

Property

38

45 43 17

30 26 92

49 44 39

34 31

Porosity undisturbed (%)

36 41

26

Porosity repack (%)

17

49

13

9 3

28 14 12

Specific retention (%)

26

44

14

40 41

6 16 16

Specific yield (%)

ENGINEERING GEOLOGY

315

8. HYDROGEOLOGY

1

8.1.1. THE INTERNATIONAL ASSOCIATION OF HYDROGEOLOGISTS The International Association of Hydrogeologists (IAH) is a professional association for those within disciplines related to groundwater, its occurrence, utilisation, testing and management. IAH is an international, scientific and educational organisation and was established to foster cooperation and information exchange related to the study of groundwater. IAH is non-government and non-profit and has over 3000 members from 120 countries. The Association is affiliated with the International Union of Geological Sciences (IUGS), and was founded during the 20th International Geological Congress in 1956.

The Australian national chapter was founded in 1978 and is one of the most active. Activities are organised nationally and within each state or territory. State branches have their own meetings. Conferences are held in Australia every two to three years, and seminars are held more frequently. The national Newsletter is published quarterly. Members are entitled to use ‘MIAH’ (Member of the International Association of Hydrogeologists) after their name. Anyone directly or indirectly engaged in study, research, or management of water in its various forms related to hydrogeology is eligible to become a member.

1

Contact:

Revised by Mr R Ellis, Hydrogeologist with the Queensland Department of Natural Resources. Much of the new information herein was provided by that Department, with their permission.

Website:

http://www.ngu.no/iah

E-mail:

[email protected]

8.1.2. AUSTRALASIAN HYDROGEOLOGY AUTHORITIES State and National water authorities maintain groundwater databases, and control water use by a licensing system. All Australian States and Territories licence water bore drillers, and require water bores to be constructed and decommissioned to a set of standards. These are described in The Minimum Construction Requirements for Water Bores in Australia, published by the Agriculture and Resource Management Council of Australia and New Zealand (1997), and available from all state water authorities. The following agencies are involved in water resource investigations and management in Australia, Papua New Guinea and New Zealand.

BUREAU OF RURAL SCIENCES Postal address:

CSIRO LAND AND WATER DIVISION (EIGHT LOCATIONS) Adelaide Laboratory

Postal address: Private Bag No 2, Glen Osmond, SA 5064 Phone: (08) 8303 8400 Fax: (08) 8303 8590 E-mail: [email protected] Internet: www.clw.csiro.au Albury Laboratory

Postal address:

PO Box E11, Kingston, ACT 2604

PO Box 921, Albury, NSW 2640

Phone: (02) 6272 4282 Fax: (02) 6272 4747 E-mail: [email protected] Internet: www.brs.gov.au

Phone: (02) 6058 2300 Fax: (02) 6043 1626 E-mail: [email protected] Internet: www.clw.csiro.au

Field Geologists’ Manual

317

HYDROGEOLOGY

Atherton Laboratory

Townsville Laboratory

Postal address:

Postal address:

PO Box 780, Atherton, QLD 4883

Private Mail Bag, PO Aitkenvale, QLD 4814

Phone: (07) 0918 800 Fax: (07) 0913 245 E-mail: [email protected] Website: www.clw.csiro.au

Phone: (074) 7538 8500 Fax: (074) 7538 8600 E-mail: [email protected] Internet: www.clw.csiro.au

Brisbane Laboratory

WESTERN AUSTRALIAN WATER AND RIVERS COMMISSION

Postal address: 80 Meiers Road, Indooroopilly, QLD 4068 Phone: (07) 3896 9516 Fax: (07) 3896 9525 E-mail: [email protected] Internet: www.clw.csiro.au Canberra Laboratory

Postal address: GPO Box 1666, Canberra, ACT 2601 Phone: (02) 6246 5700 Fax: (02) 6246 5800 E-mail: [email protected] Internet: www.clw.csiro.au Griffith Laboratory

Postal address: Private Bag 3, Griffith, NSW 2680 Phone: (02) 6960 1500 Fax: (02) 6960 1600 E-mail: [email protected] Internet: www.clw.csiro.au Perth Laboratory

Postal address: Private Bag, PO Wembley, WA 6014 Phone: (08) 9333 6200 Fax: (08) 9387 8211 E-mail: [email protected] Internet: www.clw.csiro.au

Postal address: PO Box 6740, Hay Street, East Perth, WA 6892 Phone: (08) 9278 0300 Fax: (08) 9278 0301 E-mail: [email protected] Website: www.wrc.wa.gov.au

VICTORIAN DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENT Postal address: Head Office, 8 Nicholson Street, East Melbourne, VIC 3002 Phone: (03) 9637 8000 Fax: (03) 9637 8148 E-mail: available from web site Internet: www.nre.vic.gov.au

MINERAL RESOURCES TASMANIA Postal address: PO Box 56, Rosny Park, TAS 7018 Phone: (03) 6233 8333 Fax: (03) 6233 8338 E-mail: [email protected] Internet: www.mrt.tas.gov.au

PRIMARY INDUSTRIES AND RESOURCES SOUTH AUSTRALIA Postal address: GPO Box 1671, Adelaide, SA 5001 Phone: (08) 8463 3345 Fax: (08) 8463 3342 E-mail: available from web site Website: www.pir.sa.gov.au

318

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HYDROGEOLOGY

QUEENSLAND DEPARTMENT OF NATURAL RESOURCES Postal address:

Phone: (02) 9228 6666 Fax: (02) 9233 4357 E-mail: [email protected] Internet: www.dlwc.nsw.gov.au

INSTITUTE OF GEOLOGICAL AND NUCLEAR SCIENCES—NEW ZEALAND

80 Meiers Road, Indooroopilly, QLD 4068 Phone: (07) 3896 9332 Fax: (07) 3896 9625 E-mail: [email protected] Internet: www.dnr.qld.gov.au

Postal address: PO Box 30-368, Lower Hutt, NZ

NORTHERN TERRITORY DEPARTMENT OF LANDS, PLANNING AND ENVIRONMENT Postal address:

Phone: +64 4 570 1444 Fax: +64 4 570 4603 E-mail: available from web site Internet: www.gns.cri.nz

GEOLOGICAL SURVEY OF PAPUA NEW GUINEA

PO Box 30, Palmerston, NT 0831

Postal address:

Phone: (08) 8999 3662 Fax: (08) 8999 9366 E-mail: [email protected] Internet: www.lpe.nt.gov.au

Box 778, Port Moresby, PNG

NEW SOUTH WALES DEPARTMENT LAND AND WATER CONSERVATION

Phone: +67 5 3212422 Fax: +67 5 3211360

Postal address: GPO Box 39, SYDNEY, NSW 2001

8.2.1. APPROXIMATE WATER SUPPLY REQUIREMENTS FOR HOMES 1 AND FARMS WATER REQUIREMENTS FOR DWELLINGS Purpose Per person, for all purposes

Requirement

Requirement

Av. household

225 000 L/yr

Hand basin

5 L/usage

Washing machine

40-265 L/load

Bath

50-150 L

Hose, 12 mm

680 L/h

Shower

40-250 L

Hose, 19 mm

1140 L/h

Lawn sprinkler

650 L/h

Dripping tap

150 L/d

Full flush toilet Dishwasher

1.

200 L/d

Purpose

12 L 20-90 L/load

From DNR Water Facts (Dept of Natural Resources: Brisbane), by permission.

Field Geologists’ Manual

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HYDROGEOLOGY

LIVESTOCK WATER USE (litres per day) Type

Average and peak

Type

Average and peak

Dairy cow, in milk

70-85

Horses, working

Dairy cow, dry

45-60

Horses, grazing

35-45

Beef cattle

45-60

Brood sows

22-30

Calves

22-30

Mature pigs

11-15

Nursing ewes, dry feed

9-11.5

Laying hens

0.3-0.4

7-8.5

Non-laying hens

0.18-0.23

Turkeys

0.55-0.7

Mature sheep, dry feed Mature sheep, irrigated pasture Fattening lambs, dry pasture

3.5-4.5

Fattening lambs, irrigated pasture

1.1-1.5

55-60

2.2-3

8.2.2. WINDMILL PUMPING CAPACITY Mill Diameter (m)

1

Nominal diameter of pump cylinder (mm) 50

60

65

70

75

Total head (m)

Av. Output (L/d)

Total Head (m)

Av. Output (L/d)

Total Head (m)

Av. Output (L/d)

Total Head (m)

Av. Output (L/d)

Total Head (m)

Av. Output (L/d)

1.8

18

4700

16

6000

13

7400

11

9000

10

10 700

2.4

33

5200

28

6600

23

8100

20

9800

17

11 700

3.0

60

5100

51

6400

43

7900

37

9600

32

11 400

3.6

72

5500

68

7000

58

8600

49

10 400

43

12 400

4.3

113

4700

95

6000

81

7400

69

8900

60

10 500

1.

320

From DNR Water Facts W44, March 1995 (Dept of Natural Resources: Brisbane), by permission.

Field Geologists’ Manual

HYDROGEOLOGY

8.2.3. VOLUMES CORRESPONDING TO STANDARD PIPE SIZES

1

Volume = Pipe inner diameter in millimetres2 × 0.000 7854 = volume in litres per metre length. Internal dia (mm)

Volume (l/m)

Internal dia (mm)

Volume (l/m)

Internal dia (mm)

Volume (l/m)

10

0.08

120

11.3

320

80.4

15

0.18

130

13.3

330

85.6

20

0.31

140

15.4

340

90.8

25

0.49

150

17.7

350

96.2

30

0.71

160

20.1

360

102

35

0.96

170

22.7

370

108

40

1.26

180

25.4

380

113

45

1.59

190

28.4

390

119

50

1.96

200

31.4

400

126

55

2.38

210

34.6

410

132

60

2.83

220

38.0

420

139

65

3.32

230

41.6

430

145

70

3.85

240

45.2

440

152

75

4.42

250

49.1

450

159

80

5.03

260

53.1

460

166

85

5.67

270

57.3

470

173

90

6.36

280

61.6

480

181

95

7.09

290

66.1

490

189

100

7.85

300

70.7

500

196

110

9.50

310

75.5

600

283

1.

See Section 10.1 for volumes of standard drill hole sizes.

Field Geologists’ Manual

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HYDROGEOLOGY

8.2.4. GRAPH SHOWING FLOW FROM VARIOUS DIAMETER PIPES

1.

322

From NSW Water Conservation and Commission (after E Smith), by permission.

1

Irrigation

Field Geologists’ Manual

HYDROGEOLOGY

8.2.5. FACTORS FOR CALCULATING VOLUME OF PARTIALLY FILLED 1 HORIZONTAL CIRCULAR TANKS

1.

Ratio a/d

Per cent of volume

Ratio a/d

Per cent of volume

Ratio a/d

Per cent of volume

0.01

0.169

0.35

31.192

0.70

74.768

0.05

1.869

0.40

37.353

0.75

80.449

0.10

5.204

0.45

43.644

0.80

85.763

0.15

9.405

0.50

50.000

0.85

90.595

0.20

14.237

0.55

56.356

0.90

94.796

0.25

19.551

0.60

62.647

0.95

98.131

0.30

25.232

0.65

68.808

1.00

100.000

From Department of Natural Resources, Queensland, Driller’s Note Book, Table 9, by permission.

8.2.6. CONVERSION FACTORS FOR UNITS OF PRESSURE

1.

1

psi

atms

Feet head of water

Inches head of water

kg/cm2

Metres head of water

Inches of mercury

mm of mercury

bar

kPa (Exact conversion factor)

1

0.0680

2.3108

27.730

0.0703

0.7043

2.0360

51.754

0.0689

6.894 757

14.696

1

33.959

407.51

1.0332

10.351

29.291

760.57

1.0132

101.325

0.4327

0.0294

1

12

0.0304

0.3048

0.8811

22.396

0.0298

2.983 6959

0.0361

0.0024

0.0833

1

0.0025

0.0254

0.0734

1.8644

0.0025

0.248 641 32

14.223

0.9678

32.867

394.41

1

10.018

28.959

736.11

0.9807

98.0665

1.4223

0.0966

3.2808

39.371

0.0998

1

2.8907

73.479

0.0979

9.789 0284

0.4912

0.0334

1.1350

13.620

0.0345

0.3459

1

25.419

0.0339

3.386 3837

0.0193

0.0013

0.0446

0.5358

0.0014

0.0136

0.0393

1

0.0013

0.133 2219

14.504

0.9869

33.515

402.19

1.0197

10.216

29.530

750.63

1

100

0.1450

0.0099

0.3352

4.0219

0.0102

0.1022

0.2953

7.5063

0.01

1

Calculated from the exact conversion factors shown in the kPa column, from AS/NZS 1376:1996.

Field Geologists’ Manual

323

1

8.2.7. CONVERSION FACTORS FOR PUMPING TEST UNITS

HYDROGEOLOGY

324

Field Geologists’ Manual

HYDROGEOLOGY

1.

From Kruseman G P and De Ribber, N A, 1991. Analysis and evaluation of pumping test data, Bulletin 11, International Institute for Land Reclamation and Improvement, by permission.

Field Geologists’ Manual

325

HYDROGEOLOGY

8.2.8. CIRCULAR ORIFICE METER DISCHARGE TABLE

150 NB Orifice Barrel

Clear Observation Tube

Reference Scale

10 NB Pet Cock

10 NB Pet Cock

Central Reference Point

From Bore

Orifice Meter

1.2 m to nearest bend tee or valve

610mm

Orifice Plate

Rubber Gasket Pipe Support

Ground Level

Orifice meter plate diameter (mm) 25 51 76 102 114

Formula Q = 0.0115774ch 0.5 Where Q = Discharge in litres per second c = Discharge coefficient h = Height in millimetres of water in tube

Tube height mm 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700

25 mm L/s m3/d 0.426 0.602 0.738 0.852 0.952 1.043 1.127 1.205 1.278 1.347 1.413 1.475 1.536 1.594 1.650 1.704 1.756

37 52 64 74 82 90 97 104 110 116 122 127 133 138 143 147 152

Plate diameter 76 mm L/s m3/d

51 mm L/s m3/d 1.759 2.488 3.047 3.519 3.934 4.309 4.655 4.976 5.278 5.563 5.835 6.094 6.343 6.583 6.814 7.037 7.254

152 215 263 304 340 372 402 430 456 481 504 527 548 569 589 608 627

4.062 5.745 7.036 8.125 9.084 9.951 10.748 11.495 12.187 12.847 13.474 14.073 14.648 15.200 15.734 16.250 16.750

351 496 608 702 785 860 929 993 1053 1110 1164 1216 1266 1313 1359 1404 1447

c 3.68 15.2 35.1 69.3 94.2

102 mm L/s m3/d 8.021 11.343 13.892 16.042 17.935 19.647 21.221 22.686 24.062 25.364 26.602 27.785 28.920 30.011 31.065 32.083 33.071

693 980 1200 1386 1550 1697 1834 1960 2079 2191 2298 2401 2499 2593 2684 2772 2857

114 mm L/s m3/d 10.903 15.419 18.884 21.806 24.379 26.706 28.846 30.838 32.708 34.478 36.160 37.768 39.311 40.794 42.226 43.611 44.953

942 1332 1632 1884 2106 2307 2492 2664 2826 2979 3124 3263 3396 3525 3648 3768 3884

L/s Litres per second m3/d Cubic metres per day For use with 152 mm outer diameter aluminium orifice meter. Tables based on water temperature of 16°C. Source: Queensland Department of Natural Resources.

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Field Geologists’ Manual

HYDROGEOLOGY

8.2.9. RECTANGULAR AND V-NOTCH WEIR BOARD DISCHARGE TABLE 300 mm

Reference Point

610 mm or 305 mm

Reference Point

90

150 mm

150 mm

150 mm

V Notch

Weir Board V – Notch

Rectangular

0.17556H 2.48 Q= 3600

0.20955(L − 0.2H)H1.5 Q= 3600

Q = Discharge in litres per second H = Depth in millimetres of water over weir L = Width in millimetres of weir crest

Weir board discharge tables Depth mm

305 mm Board

V - Notch L/s

m3/d

10

0.015

1

20

0.052

7

30

0.225

40

0.458

50 60

610 mm Board

914 mm Board

L/s

m /d

3

L/s

m /d

3

19

2.858

247

5.773

499

8.658

751

40

4.371

378

8.859

765

13.347

1153

0.797

69

6.067

524

12.340

1.066

18.612

1608

1.253

108

7.921

684

16.167

1397

24.412

2109

70

1.836

159

9.913

857

20.304

1754

30.695

2652

80

2.557

221

12.029

1039

24.724

2136

37.419

3233

90

3.425

296

14.254

1232

29.402

2540

44.550

3849

100

4.448

384

16.578

1432

34.320

2965

52.062

4498

110

5.633

487

18.991

1641

39.460

3409

59.929

5178

120

6.990

604

21.486

1856

44.808

3871

68.131

5886

130

8.525

737

24.054

2078

50.352

4350

76.649

6623

140

10.245

885

26.690

2306

56.079

4845

85.469

7384

150

29.386

2539

61.980

5355

94.574

8171

160

32.137

2777

68.044

5879

103.951

8981

170

34.939

3019

74.264

6416

113.590

9814

180

37.785

3265

80.631

6967

123.477

10668

190

40.673

3514

87.138

7529

133.604

11543

L/s

3

m /d

Source: Queensland Department of Natural Resources.

Field Geologists’ Manual

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HYDROGEOLOGY

8.2.10. PRESSURE CORRESPONDING TO HEAD OF WATER Head (m)

Pressure (kPa)

Head (m)

Pressure (kPa)

Head (m)

1

Pressure (kPa)

1

9.796

50

489.80

350

3428.6

2

19.592

60

587.76

400

3918.4

3

29.388

70

685.72

450

4408.2

4

39.184

80

783.68

500

4898.0

5

48.980

90

881.64

1000

9796.0

6

58.776

100

979.6

7

68.572

120

1175.5

8

78.368

140

1371.4

9

88.164

160

1567.4

10

97.96

180

1763.3

20

195.92

200

1959.2

30

293.88

250

2449.0

40

391.84

300

2938.8

1.

Calculated for water at maximum density (4º or 39.2ºF), when P in psi = 0.4334 H in feet, and P in kilopascals = 9.796 H in metres. At 20ºC and one atmosphere, one foot head of water = 0.432 749 psi and one metre head of water = 9 .789 04 kPa.

8.3.1. NOTES ON WATER SAMPLING A water analysis is essential before water is used for stock, domestic or irrigation purposes. The chemical and biological characteristics of the water can affect crops, animals or humans. Correct sampling of groundwater is a specialist field. The accuracy of the final analysis is dependent on the sample being taken correctly from the bore, knowledge of the water source, the correct use of preservatives, and the elapsed time until the sample is analysed. These notes outline the reasons for groundwater sampling (see Table 1), some of the methods of sampling and equipment used (see Table 2) and types of bottles and preservation methods (see Table 3). If a serious groundwater sampling program is to be undertaken, it is essential to liase with an hydrogeologist and the laboratory analysing the samples. Before a representative sample can be taken from a bore, the stale water must be removed. Generally three times the volume of water in the bore should be pumped out. The pump rate, the type of pump, the standing water level and the date should be recorded.

328

Some parameters such as pH, temperature and dissolved oxygen need to be measured in the field. Sensitive parameters such as heavy metals and pesticides need special bottles and preservatives. Bottles should be cleaned prior to sampling, and filled to the top with no air gap. They should be labelled with the date and the details of the source (bore, well, tap etc) and the sampler. For the most reliable results, the time between the sampling and the analysis should be kept to a minimum. Bacteriological samples need to be collected in sterile containers, supplied by the laboratory. These should be cooled and sent immediately for analysis. A standard chemical analysis usually shows major ions, electrical conductivity, pH and a range of other parameters. Generally, a water sample taken from a drill hole during drilling will be suitable only for analysis of major ions, as other parameters such as dissolved gases and pH will be disturbed. There are numerous laboratories and consultants that can arrange or do the groundwater sampling and analysis.

Field Geologists’ Manual

HYDROGEOLOGY

TABLE 1 Reasons for determining water quality parameters. Parameter

Reason for sampling

Bacteria

The coliform group of organisms is the primary bacterial indicator recommended for testing for the presence of faecal pollution. Although coliforms may be derived from non-faecal sources (eg soil, vegetation) the fact that they are present in large numbers in the faeces of man and other warm blooded animals means they can be detected even after considerable dilution. The presence of faecal coliforms, in particular Eschericha coli, provides definite evidence of faecal pollution, hence points to possible presence of pathogenic organisms. Iron bacteria are a serious problem in some areas, causing damage to bore casing and pumps.

Ca Mg K Na (positively charged) H/CO3/SO4 (negatively charged)

These are all major ions, which are general water quality indicators. Generally dissolved in concentrations of milligrams per litre (mg/L), the major ions are present in water bodies as a result of weathering. Fluctuations over time can occur as a result of land clearing, irrigation and climatic cycles.

Conductivity

Conductivity is the measure of the ability of an aqueous solution to carry an electric current. This ability depends on the presence of ions; on their total concentration, mobility and valence; and the temperature at measurement. Conductivity is an indicator of other parameters and is used mainly to give a quick indication of Total Dissolved Ions (TDI), which for many waters may be useful as an estimator for Total Dissolved Solids (TDS).

Cu Pb Cd Ni Cr Zn Fe Mn Al Se Hg and As

Metals that are present in trace amounts (ng/L or µg/L). Some of the metals can be toxic to humans and stock in larger concentrations or different oxidation states. The metals are present as a result of weathering or discharge from industry and their ability to stay in solution is affected by pH and DO.

Cyanide CN

Can be an indicator of leakage from industrial or mineral processes, especially gold mining.

Dissolved oxygen (DO)

Oxygen has a key role in many important chemical reactions. Can indicate corrosive conditions.

Gross and ß radiation

Indicators of the presence of radionuclides and are useful to determine whether testing for specific radionuclides is required.

Pesticides

Organochlorides, organo-phosphates, herbicides, and fungicides are a few examples. The presence in water limits or prohibits use for stock or domestic purposes.

pH

pH or hydrogen ion activity is an indicator of relative alkalinity or acidification. pH has a direct influence on the chemistry of the water body, altering the composition of some elements and making the water encrusting or corrosive.

Silica

High levels of silica cause encrustation when water is boiled.

Temperature

It is used in conjunction with pressure and salinity to calculate DO per cent from DO mg/L. It can be used as an indicator of aquifer conditions.

Total Dissolved Solids (TDS)

TDS are those solids ‘in solution’ that pass through a filter of standard pore size and will include dissolved salts, silica and colloidal material. TDS = Silica + Total Anions + Total Cations - (HCO3 × 0.5083), all parameters expressed in mg/L.

Unfiltered nutrients

Total N and total P give nutrient status. In groundwater, they tend to be in the ionic forms NO3 and PO4. High levels of NO3 (> 10 mg/L as N) can be toxic, especially to newborn babies. Nutrients promote the growth of algae.

Source: Water Quality Sampling Guidelines, Department of Natural Resources, Queensland, 1999, in preparation.

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HYDROGEOLOGY

TABLE 2 Sampling devices - advantages and disadvantages. Sampling equipment Bailer

Yield NA

Advantages • • • • • •

Can be constructed from variety of material compatible with parameter of interest Can be different diameter and length to suit the sampling point No external power source required Easy to clean or disposable Inexpensive and readily available Lower surface area to volume ratio reduces outgassing of volatile organics

Disadvantages • • • • • •

Syringe devices

NA

• • • • • • • • •

Air-lift sampler

Dependant upon capacity of compressor and bore, and the submergence of the airpipe

Suction-lift pumps

Flow rate high. • Low head, < 8 m • • • •

Neither aeration nor outgassing occurs as it does not come in contact with atmospher Can be made of inert or any material Inexpensive, highly portable and simple to operate Can be used in small diameter wells Sample can be collected at various intervals

• • • •

Flow rate 1 L/min. head over 100 m

• • •

Submersibe 15 - 30 L/min pump 9-90 m head

• • • • •

Inertial pump

> 5 L/min 45 m head (these are quite optimistic figures)

• • • •

Inefficient for collecting large samples Syringes can not be used for evacuating stagnant water The use of syringes is limited to water with a low suspended solids content Some leakage may occur around the plunger when syringes are used to sample water containing high level of suspended solids

Relatively portable • Readily available Inexpensive Some are suitable for well • development–depends on yield rate of device •

Causes changes in carbon dioxide concentration and thus not suitable for sampling for pH-sensitive parameters Because of degassing effect on sample it is not appropriate method of sampling for detailed chemical analysis Aeration is impossible to avoid unless elaborate precautions are taken

• •

Limited sampling depth (6-8 m) Loss of dissolved gases and volatiles due to vacuum effect Potential of hydrocarbon contamination of samples due to use of petrol or diesel for running the pump Use of centrifugal pumps results in aeration and turbulence

Highly portable Easily available Flow rate can be controlled Inexpensive Can be constructed in small diameter

• •

Bladder pump

Time consuming, non-continuous flow The person sampling the bore is susceptible to exposure to any contaminants in the sample It may be difficult to determine the point within the water column that the sample represents Can be impractical to remove storage water in a deep bore with a bailer Aeration may result during transfer of sample from bailer to sample bottle Bailer check valves may fail to function properly

• Portable, small diameter Non-contact, gas driven pump that uses • compressed air to expand and contract • flexible bladder Minimal effect on water chemistry because of non-contact and exclusion from the atmosphere

Non-continuous flow Low flow rate Time consuming to purge bore

• Constructed from various materials Wide range of diameters Readily available High pumping rates are possible for • evacuation of large volumes Provides a continuous sample over • extended periods of time •

Conventional units are unable to pump sediment laden water without incurring damage to pump Smallest diameter pump is relatively inexpensive Most of submersible pumps are too large for 50 mm diameter pumps Must be able to pump at low rate for sampling and a high rate for purging

• Simple construction, inexpensive Manual, gas or electric motor driven Good for sediment clogged bores If dedicated, it avoids cross- • contamination •

For use primarily in small diameter bores as large bores increase the possibility of tubing sway Works optimally with deep installation of tubing. This may result in the bore not being properly purged Low flow capacity

Source: Based on Murray-Darling Basin Groundwater Quality Sampling Guidelines Murray-Darling Basin, Canberra, August, 1997. (Originally from Jiwan and Gates, 1992).

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TABLE 3 Summary of bottle type, preservative required and holding times for water quality samples. PARAMETERS TO BE MEASURED Silica and FILTRATE Filterable reactive P, major ions Oxides of N, Ammonia (Filtered nutrients) Sample volume Bottle type

Filtered

Metals

Bacteria

Pesticides

Gross and ß Other indicators radiation Cyanide = 1 Selenium = 2 Mercury = 3 Aluminium = 4

100 mL

1L

500 mL

125 mL

1L

1L

1=1L 2,3,4 = 500 mL

P(R)

P(D)

P(A)

G (sterile) P (sterile)

G(S)

P(S)

1 = P(R) 2 = P(A) 3 = G(A) 4 = P(A)

Yes

No

No/Yes

No

No

No

No

20 mm

No

10 mm for acid

10 mm air space

No

No

No

None

None

5 mL conc. HNO3

None

None

5 mL conc. HNO3

1 = 5 mL NaOH 2 = 5 mL HNO3 3 = 5 mL HNO3 then 5 mL potassium dichromate 4 = 5 mL HNO3

Cooling requirement

Refrigerate immediately, freeze within 12 hours

Not required

None

Refrig.

Refrig.

None

1 = refrigerate 2,3,4 = None

Store in dark

No

No

No

No

Yes

No

1 = Yes 2,3,4 = No

Delivery time limit

24 hours chilled 28 days frozen

14 days

28 days

24 hours

7 Days

No limit

1 = 24 hours 2 = 28 days 3 = 3 days 4 = 28 days

Air space in bottle Additive

Bottle Types: P Polyethylene G Glass Bottle Preparation: (A) Acid Washed (D) Detergent Washed (S) Solvent Washed (R) Reverse Osmosis Water Washed Cooling: Refrigerate 1°C to 4°C Freeze −4°C or lower Source: Water Quality Sampling Guidelines, Department of Natural Resources, Queensland, 1999, in preparation. Reference: Murray-Darling Basin Groundwater Quality Sampling Guidelines, Murray-Darling Basin, Canberra, August, 1997.

8.3.2 GUIDELINES FOR CHARACTERISTICS OF DRINKING WATER The determination of drinking water quality is a complex subject. This table shows values and comments about common quality parameters used in the determination of drinking water suitability. Organic compounds (including pesticides, fungicides and herbicides) are not presented as they are numerous and

Field Geologists’ Manual

sometimes difficult to determine. The assessment of the microbiological content of water is a specialised field and is not covered here. Water that has been distributed by metallic pipes may contain higher concentrations of metals such as zinc, copper, chromium and cadmium.

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HYDROGEOLOGY

The following information is given as a guide only. For further information, refer to the full text of Australian Drinking Water Guidelines, 1996 NHMRC. Characteristic

Guideline values

Comments

#

Health Aesthetic ** > 85 per cent

Dissolved oxygen pH

6.5 - 8.5

Hardness as CaCO3

**

200

Total dissolved solids Aluminium (acid soluble) Ammonia (as NH3) Arsenic Barium Boron Cadmium Chloride Chromium (as Cr (VI)) Copper Cyanide Fluoride Iron Lead Manganese Mercury

** *

500 0.2 0.5

0.007 0.7 0.3 0.002 ** 0.05 2 0.08 1.5 * 0.01 0.5 0.001

Molybdenum Nickel Nitrate (as nitrate)

0.05 0.02 50

Selenium Sodium Sulfate Zinc

0.01 ** 500 *

250 1

0.3 0.1

180 250 3

Groundwater usually has low oxygen concentrations that can allow toxic trace elements to enter or remain in solution Extreme pH values may adversely affect health, and can allow toxic trace elements to enter or remain in solution Caused by calcium and magnesium salts. Hard water is difficult to lather and can cause encrustations 500-1000 is acceptable based on taste < 0.1 mg/L is desirable Presence may indicate sewage contamination or agricultural activities From natural sources and mining/industrial/agricultural wastes From natural sources From natural sources or contamination From industrial or agricultural contamination From natural sources or contamination From industrial/agricultural contamination From natural sources From industrial waste, some plants and bacteria From natural sources From natural sources From natural sources From natural sources. Contributes to hardness Low concentrations from natural sources, from industrial processes and effluent From natural sources, higher concentrations from mining and agriculture From natural sources From natural sources and pollution from sewage and agricultural activities Generally low concentrations from natural sources From natural sources From natural sources Generally low concentrations from natural sources

#

Aesthetic values are not listed if the chemical does not cause aesthetic problems, or if the value determined from health considerations is lower. * Insufficient data to set a guideline value based on health considerations. ** No health-based guideline value is considered necessary. Note: All values except pH and dissolved oxygen in milligrams per litre (mg/L). Source: Adapted from Australian Drinking Water Guidelines, 1996, National Health and Medical Research Council and Agriculture and Resource Management Council of Australia and New Zealand.

8.3.3. RECOMMENDED STOCK WATER QUALITY Good quality water is essential for successful livestock production through the maintenance of animal health and fertility. Contaminants in water may produce residues in animal products and creating human health risks. Some of the common parameters are given below. It is emphasised that other water quality parameters can have an effect on the suitability of water, and should be taken into consideration when determining whether water is suitable for this livestock drinking.

332

Calcium Stock should tolerate concentrations of calcium in water up to 1000 mg/L, if calcium is the dominant cation and dietary phosphorous levels are adequate. Magnesium Insufficient information is available to set a guideline value for magnesium in livestock drinking water.

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Nitrate and Nitrite Nitrate concentrations less than 400 mg/L in livestock drinking water should not be harmful to animal health. Water containing more than 1500 mg/L nitrate is likely to be toxic to animals and should be avoided.

Recommended water quality guideline values (low risk) for heavy metals and metalloids in livestock drinking water Metal or metalloid Aluminium Arsenic

Sulfate Adverse effects to stock are not expected if the concentration of sulfate in drinking water does not exceed 1000 mg/L. Levels of sulfate greater than 2000 mg/L may cause chronic or acute health problems in stock. Total Dissolved Solids (TDS)

Beryllium Boron Cadmium Chromium Cobalt Copper

The following table outlines the recommended concentrations of Total Dissolved Solids in drinking water for livestock. Tolerances of livestock to drinking water total dissolved solids Livestock

Beef cattle Dairy cattle Sheep Horses Pigs Poultry *

TDS (mg/L) No adverse effects on animals expected

Animals may have initial reluctance to drink or there may be some scouring, but stock should adapt without loss of production

0-4000 0-2500 0-5000 0-4000 0-4000 0-2000

4000-5000 2500-4000 5000-10 000 4000-6000 4000-6000 2000-3000

Loss of production and a decline in animal condition and health would be expected. Stock may tolerate these levels for short periods if introduced gradually 5000-10 000 4000-7000 10 000-13 000* 6000-7000 6000-8000 3000-4000

Sheep on lush green feed may tolerate up to 13 000 mg/L TDS without any loss of condition or production.

Heavy metals and metalloids Stock tolerance to many metals in drinking water is also dependent on dietary intake of the metal. The guidelines in the table are the metal concentrations below which there is a minimal risk of toxic effects.

Field Geologists’ Manual

Fluoride Iron Lead Manganese Mercury Molybdenum Nickel Selenium Uranium Vanadium Zinc

Guideline value (low risk) (mg/L) 5 0.5 5* ND 5 0.01 1 1 0.5 (sheep) 1 (cattle) 5 (pigs) 5 (poultry) 2 Not sufficiently toxic 0.4 Not sufficiently toxic 0.002 0.05 1 0.02 0.2 ND 20

*

It may be tolerated if not provided as a food additive and natural levels in the diet are low. ND Not determined, insufficient background data to calculate.

Pesticides and other organic toxicants In the absence of adequate information on pesticides derived specifically for livestock under Australian and New Zealand conditions, it is recommended that, as a conservative measure the Australian Drinking Water Guidelines, 1996, National Health and Medical Research Council and Agriculture and Resource Management Council of Australia and New Zealand be adopted for stock drinking water quality. Source: Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Draft, July, 1999, Australian and New Zealand Environment and Conservation Council, and Agriculture and Resource Management Council of Australia and New Zealand.

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8.3.4. RECOMMENDED IRRIGATION WATER QUALITY Salinity is the term used when referring to the presence of soluble salts in waters or in or on soils. It is an important factor when considering the suitability of waters and soils for growing crops. However, the suitability of particular water for irrigation depends also on factors such as toxicity of specific metals, pH, and other parameters. The suitability of the water will also depend on the salt tolerance of the crop, the climate, the soil and the irrigation practice. It is recommended that specialist assess all of the above factors to determine the suitability of a particular water for a particular crop under a given set of circumstances. The following information is a general guide for determining suitability of waters for a variety of crops on a variety of soils. The Electrical Conductivity (EC) of water is measured in microsiemens per centimetre (µS/cm). The salinity of soils is usually measured in decisiemens per metre (dS/cm).

Average root zone salinity (ECse) can then be calculated from the following equation: EC se =

EC i 2.2 LF

where: ECse = Average root zone salinity in dS/m. Eci = Electrical conductivity of irrigation water in dS/m. LF = Average leaching fraction.

TABLE 2 Soil and water salinity criteria based on plant salt tolerance groupings. Water or soil salinity rating

Plant salt tolerance grouping

(1 dS/m = 1000 µS/cm)

Average root zone salinity or EC se (in dS/m)

The Average Root Zone Salinity (ECse) indicates the salt content of the soil-water in the crop’s root zone. The Average Root Zone Leaching Fraction (LF) is the fraction of applied water that passes the root zone.

Sensitive crops

Very low

< 0.95

Moderately sensitive crops Moderately tolerant crops Tolerant crops

Low

0.95 - 1.9

Medium

1.9 - 4.5

TABLE 1 Soil type and average root zone leaching fraction.

Very tolerant crops Generally too saline

Soil Type

Average root zone LF

High

4.5 - 7.7

Very high

7.7 - 12.2

Extreme

> 12.2

0.6 0.33 0.33 0.2

Sand Loam Light clay Heavy clay

TABLE 3 Tolerance of plants to salinity in irrigation. Common name

Sorghum Barley Cotton Sugarbeet Safflower Wheat Sunflower Oats Soybean Rice Sugarcane

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Scientific name

Sorghum bicolor Hordeum vulgare Gossypium hirsutum Beta vulgaris Carthamus tinctorius Triticum aestivum Helianthus annual app. Avena sativa Glycine max Oryza sativa Saccharum officinarum

Average root zone salinity threshold (ECse) Field crops 6.8 8.0 7.7 7.0 6.5 6.0 5.5 5.0 5.0 3.0 1.7

ECi threshold for crops growing in Sand

Loam

Clay

9.4 12.6 12.1 11.0 8.2 9.4 7.5 7.0 7.0 4.8 4.3

5.3 7.2 6.9 6.3 4.7 5.3 4.3 4.0 4.0 2.7 2.5

3.1 4.2 4.0 3.7 2.7 3.1 2.5 2.3 2.3 1.6 1.4

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TABLE 3 (cont.) Tolerance of plants to salinity in irrigation. Common name

Fig Date Olive Peach Rockmelon Orange Grape Avocado Apple Lemon Strawberry

Scientific name

Average root zone salinity threshold (EC se )

Chloris gayana Cynodon dactylon Pennisetum clandestinum Sorghum sudanense Trifolium alexandrinum

Fruits 4.2 4.0 4.0 3.2 2.2 1.7 1.5 1.3 1.0 1.0 1.0 Pastures 7.0 6.9 3.0 2.8 2.0

Ficus carica Phoenix dactylifera Olea europaea Prunus persica Cucumis melo Citrus sinensis Vitis spp. Persea americana Malus sylvestris Citrus limon Fragaria

ECi threshold for crops growing in Sand

Loam

Clay

5.3 8.7 5.1 4.7 4.6 2.9 3.3 2.3 2.0 1.3 1.6

3.0 5.0 2.9 2.7 2.6 1.7 1.9 1.3 1.2 0.7 0.9

1.8 2.9 1.7 1.6 1.5 1.0 1.1 0.8 0.7 0.4 0.5

12.8 10.8 8.0 6.5 3.8

7.3 6.1 4.6 3.7 2.2

4.2 3.6 2.6 2.1 1.3

Rhodes grass Couch grass Kikuya grass Sudan grass Clover Lucerne, Hunter river Siratro Paspalum

Medicago sativa

2.0

4.7

2.7

1.6

Macroptilium atropurpureum Paspalum dilatatum

4.2 3.7

2.4 2.1

1.4 1.2

Cauliflower Cucumber Tomato Potato Lettuce Onion Bean Carrot

Brassica oleracea Cucumis sativus Lycopersicon esculentum Solanum tuberosum Latuca sativa Allium cepa Phaseolus vulgaris Daucus carota

2.0 1.8 Vegetables 2.5 2.5 2.3 1.7 1.3 1.2 1.0 1.0

3.2 4.2 3.5 3.2 2.7 2.3 1.9 2.2

1.8 2.4 2.0 1.8 1.5 1.3 1.1 1.2

1.1 1.4 1.2 1.1 0.9 0.8 0.6 0.7

Source: Department of Natural Resources, Queensland.

REFERENCES Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Draft, July, 1999, Australian and New Zealand Environment and Conservation Council, and Agriculture and Resource Management Council of Australia and New Zealand.

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Salinity Management Handbook, Department of Natural Resources, Queensland, 1997.

335

9. GEOPHYSICS 9.1. PHYSICAL PROPERTIES AND CONVERSION FACTORS Physical Properties The successful application of geophysics depends on a knowledge of the physical properties of the earth section being examined. Contrasting properties of the host environment and the target must be proposed in order that the appropriate geophysical technique can be selected and applied. The most commonly used properties are density, magnetic susceptibility, electrical conductivity, polarizability, radioactivity and seismic velocity. The following tables2 summarise the physical properties of many of the more common rocks and minerals. Values for particular rock units are quite often obtainable from state and federal geological survey offices. Also, measurements can be made on rock samples collected from the field of interest.

Conversion of SI units to CGS or Electromagnetic CGS units The International System of Units, denoted as SI (Système Internationale), was established in 1960 as a comprehensive electrical-mechanical-thermodynamical system of units. It is an extension of the MKSA (metre-kilogram-second-ampere) system. A useful source of information on units is ‘The Dictionary of Units’ by Frank Tapson which can be found on the Internet at http://www.ex.ac.uk/cimt/dictunit. 1.

From Sharma, P V, 1986. Geophysical Methods in Geology, 2nd Edition. (Elsevier: New York).

2.

If not stated otherwise, the following tables are taken from: Telford, W M, Geldard, L P, Sheriff, R E, 1990. Applied Geophysics, 2nd Edition, (Cambridge University Press: Cambridge), by permission.

SI units Quantity Mass Length Time Acceleration Subunit for gravity Density Force Pressure Viscosity Energy Power Heat flow Conductivity (thermal) Heat production Current Potential difference Electric field Electric charge Capacitance Resistance Resistivity Conductivity Magnetic flux Magnetic flux density (B-field) Subunit for the B-field Magnetizing field (H-field)

Field Geologists’ Manual

1

Corresponding equivalent in c.g.s. or electromagnetic c.g.s. units

Name

Symbol

kilogram metre second metres/second2 gravity unit kilogram/metre3 newton pascal pascal sec joule watt watt/metre2 watt/metre °C watt/metre ampere

kg m s m/s2 g.u. =µm/s2 kg/m3 N Pa=N/m2 Pa s J W=J/s W/m2 W/m °C A A

volt volt/metre coulomb farad ohm ohm metre siemen/metre or mho/metre weber tesla

V V/m C=A s F=C/V Ω =V/A Ωm S/m σ WB=Vs T=Wb/m2

103gm 102cm s 102 gal = 102 cm/s2 10-1milligal (mgal) 10-3 g/cm3 105 dynes 10 dynes/cm2=10-5bar 10 poise 107ergs=0.24cal 107ergs 23.9 µcal/cm2s 2.39 × 10-3cal/cm s °C 2.39 × 10-7 cal/cm3 s 10-1e.m.u. (Or ‘absolute amp’) 108 e.m.u. 106 e.m.u. 10-1 e.m.u. 10-9 e.m.u. 109 e.m.u. 1011 e.m.u. 10-11 e.m.u. 108 maxwell 104 gauss (G)

nanoTesla

nT

1γ = 10-5 gauss (G)

ampere/metre

A/m

4π10-3 oersted (Oe)

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GEOPHYSICS

SI units (cont.) Quantity Inductance

Name

Symbol

Corresponding equivalent in c.g.s. or electromagnetic c.g.s. units

henry

H=Wb/A

109 e.m.u.

-7

Permeability*

henry metre

µ o = 4π 10 H/m

1 (for vacuum)

Susceptibility

dimensionless

k

4π e.m.u.

Magnetic pole strength

ampere metre

Am

10 e.m.u.

Magnetic moment

ampere metre

2

Am

2

103 e.m.u.

Magnetization

ampere/metre

A/m

10-3 e.m.u.

* Permeability for vacuum. Further physical constants are available from Markowitz, W, 1973. SI International System of Units, Geophys. Survey, 1: 217 - 241.

Prefixes of the SI System By using appropriate prefixes the SI unit can be made bigger or smaller. For example the basic unit of length is metre. For large distances this becomes a kilometre yotta zetta exa peta tera giga mega kilo hecto deca

(Y) (Z) (E) (P) (T) (G) (M) (k) (h) (da)

deci centi milli micro nano pico femto atto zepto yocto

(d) (c) (m) (µ) (n) (p) (f) (a) (z) (y)

1 000 000 000 000 000 000 000 000 1 000 000 000 000 000 000 000 1 000 000 000 000 000 000 1 000 000 000 000 000 1 000 000 000 000 1 000 000 000 1 000 000 1 000 100 10 1 0.1 0.01 0.001 0.000 001 0.000 000 001 0.000 000 000 001 0.000 000 000 000 001 0.000 000 000 000 000 001 0.000 000 000 000 000 000 001 0.000 000 000 000 000 000 000 001

=1024 =1021 =1018 =1015 =1012 =109 =106 =103 =102 =101 =100 =10-1 =10-2 =10-3 =10-6 =10-9 =10-12 =10-15 =10-18 =10-21 =10-24

(a thousand metres); or for smaller measurements, a millimetre (a thousandth of a metre). The full range of prefixes with their symbols and multiplying factors is given below.

(a thousand millions = a billion) (a million) (a thousand)

(a thousandth) (a millionth) (a thousand millionth)

The symbol for micro (µ) is the Greek letter ‘mu’.

9.2. GRAVITY SURVEYING METHODS AND TABLES GRAVITY SURVEYS The method takes advantage of the different rock densities to map both regional and detailed structure and lithology; station spacing may vary from a few kilometres to a few metres depending on the scale of

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the target sought. Corrections applied to the basic instrument measurement include those for tidal variation (earth and sun), latitude, elevation and terrain. The final parameter is usually the bouguer anomaly which is a vertical gravity acceleration expressed in µm/s2. The older traditional units include milligals

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(mgals; 0.1mgl=1.0 µm/s2) and gravity units (gu; 1.0 g.u.=1.0 µm/s2). Vertical elevation to ten centimetre accuracy and horizontal position to one metre accuracy are usually achieved using differential GPS. Conventional measurements can be taken on land,

under water and in drill-holes. Recent developments to measure the gravity gradient from a fixed wing aircraft are available on a company proprietary basis.

TABLE 1 Densities of sediments and sedimentary rocks Rock type

Range (wet) g/cm

3

Average (wet) g/cm

3

Range (dry) g/cm

3

Average (dry) g/cm

Alluvium

1.96-2.0

1.98

1.5-1.6

1.54

Clays

1.63-2.6

2.21

1.3-2.4

1.70

-

1.80

-

-

Gravels

1.7-2.4

2.0

1.4-2.2

1.95

Loess

1.4-1.93

1.64

0.75-1.6

1.20

Sand

1.7-2.3

2.0

1.4-1.8

1.60

Sand & clays

1.7-2.5

2.1

-

-

Silt

1.8-2.2

1.93

1.2-1.8

1.43

Soils

Glacial drift

1.2-2.4

1.92

1.0-2.0

1.46

Sandstones

1.61-2.76

2.35

1.6-2.68

2.24

Shales

1.77-3.2

2.4

1.56-3.2

2.10

Limestones

1.93-2.90

2.55

1.74-2.76

2.11

Dolomite

2.28-2.90

2.70

2.04-2.54

2.30

3

Porosity is the percentage of the bulk volume of a rock that is occupied by pores, whether connected or isolated. Permeability is the capacity of a porous rock for transmitting a fluid. The usual unit is the millidarcy.

TABLE 2 Densities of igneous rocks Rock type

Range g/cm

Rhyolite glass

3

Average g/cm

3

Rock type

Range g/cm

3

Average g/cm

2.24

Quartz diorite

2.62-2.96

2.79

2.2-2.4

2.30

Diorite

2.72-2.99

2.85

Vitrophyre

2.36-2.53

2.44

Lavas

2.80-3.00

2.90

Rhyolite

2.35-2.70

2.52

Diabase

2.50-3.2

2.91

Obsidian

2.20-2.28

Dacite

2.35-2.8

2.58

Essexite

2.69-3.14

2.91

Phonolite

2.45-2.71

2.59

Norite

2.70-3.24

2.92

Trachyte

2.42-2.8

2.60

Basalt

2.70-3.30

2.99

Andesite

2.4-2.8

2.61

Gabbro

2.70-3.50

3.03

Nepheline syenite

2.53-2.7

2.61

Hornblende-gabbro

2.98-3.18

3.08

Granite

2.50-2.81

2.64

Peridotite

2.78-3.37

3.15

Granodiorite

2.67-2.79

2.73

Pyroxenite

2.93-3.34

3.17

Porphyry

2.60-2.89

2.74

Acid igneous (av.)

2.30-3.11

2.61

Syenite

2.60-2.95

2.77

Basic igneous (av.)

2.09-3.17

2.79

Anorthosite

2.64-2.94

2.78

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TABLE 3 Densities of metamorphic rocks Rock type

Range g/cm

3

Average g/cm

3

Rock type

Range g/cm

3

Average g/cm

Quartzite

2.5-2.7

2.60

Serpentinite

2.4-3.10

2.78

Schists

2.39-2.9

2.64

Slate

2.7-2.9

2.79

Graywacke

2.6-2.7

2.65

Gneiss

2.59-3.0

2.80

Granulite

2.52-2.73

2.65

Chloritic slate

2.75-2.98

2.87

Phyllite

2.68-2.8

2.74

Amphibolite

2.90-3.04

2.96

Marble

2.6-2.9

2.75

Eclogite

3.2-3.54

3.37

2.63-2.91

2.77

Metamorphic (av.)

2.4-3.1

2.74

Quartzitic slate

3

TABLE 4 Densities of nonmetallic minerals and miscellaneous materials Type Snow

Range g/cm

3

Average g/cm

3

Type

Range g/cm

3

Average g/cm

-

0.125

Gypsum

2.2-2.6

2.35

0.6-0.9

-

Bauxite

2.3-2.55

2.45

0.88-0.92

-

Kaolinite

2.2-2.63

2.53

1.01-1.05

-

Orthoclase

2.5-2.6

-

-

1.05

Quartz

2.5-2.7

2.65

Asphalt

1.1-1.2

-

Calcite

2.6-2.7

-

Lignite

1.1-1.25

1.19

Talc

2.7-2.8

2.71

Soft coal

1.2-1.5

1.32

Anhydrite

2.9-3.0

2.93

1.34-1.8

1.50

Biotite

2.7-3.2

2.92

-

1.50

Magnesite

2.9-3.12

3.03

Carnallite

1.6-1.7

-

Fluorite

3.01-3.25

3.14

Sulphur

1.9-2.1

-

Epidote

3.25-3.5

-

Chalk

1.53-2.6

2.01

Diamond

-

3.52

Graphite

1.9-2.3

2.15

Corundum

3.9-4.1

4.0

Rock salt

2.1-2.6

2.22

Barite

4.3-4.7

4.47

Zircon

4.0-4.9

4.57

Petroleum Ice Sea water Peat

Anthracite Brick

3

TABLE 5 Densities of minerals Mineral

Range g/cm

3

Average g/cm

3

Mineral

Range g/cm

3

Average g/cm

Copper

-

8.7

Silver

-

10.5

Sphalerite

3.5-4.0

-

Covellite

-

3.8

Malachite

3.9-4.03

4.0

Gold

15.7-19.4

Oxides, carbonates

Sulphides, arsenates 3.75

Limonite

3.5-4.0

3.78

Chalcopyrite

4.1-4.3

4.2

Siderite

3.7-3.9

3.83

Stannite

4.3-4.52

4.4

Rutile

4.18-4.3

4.25

Stibnite

4.5-4.6

4.6

4.5-4.8

4.65

4.4-4.8

4.7

Manganite

4.2-4.4

4.32

Pyrrhotite

Chromite

4.3-4.6

4.36

Molybdenite

340

3

Field Geologists’ Manual

GEOPHYSICS

TABLE 5 Densities of minerals (cont.) Mineral Oxides, carbonates Ilmenite

Range g/cm

3

Average g/cm3

Mineral Sulphides, arsenates

Range g/cm3

Average g/cm3 4.85

4.67

Marcasite

4.7-4.9

4.7-5.0

4.82

Pyrite

4.9-5.2

5.0

Magnetite

4.9-5.2

5.12

Bornite

4.9-5.4

5.1

Franklinite

5.0-5.22

5.12

Millerite

5.3-5.65

5.4

5.5-5.8

5.65

Pyrolusite

4.3-5.0

Hematite

4.9-5.3

5.18

Chalcocite

Cuprite

5.7-6.15

5.92

Cobaltite

5.8-6.3

6.1

Cassiterite

6.5-7.1

6.92

Arsenopyrite

5.9-6.2

6.1

Wolframite

7.1-7.5

7.32

Smaltite

6.4-6.6

6.5

Uraninite

8.0-9.97

9.17

Bismuthinite

6.5-6.7

6.57

Argentite

7.2-7.36

7.25

Niccolite

7.3-7.67

7.5

Galena

7.4-7.6

7.5

Cinnabar

8.0-8.2

8.1

9.3. MAGNETIC SURVEY METHODS AND TABLES SURVEY METHODS The physical property used is magnetic susceptibility. This is the ratio of the magnetic moment per unit volume to the magnetic field strength and, therefore, is dimensionless. The values are positive for paramagnetic materials and negative for diamagnetic materials. Most magnetic rocks present an overwhelming proportion of induced magnetism, which is due to the influence of the present day geomagnetic field. Remanent magnetism is the result of a previous geomagnetic field which is ‘frozen’ into the rock. Remanent magnetism is usually present in all magnetic anomalies to a small degree, but in some cases it is present in a much greater proportion. This has the effect of reversing the polarity of the anomaly.

Regional applications of the magnetic method are for the definition of structure and lithology. Detailed applications will have the same purpose plus the possible definition of discrete magnetic mineral bodies, eg magnetite, pyrrhotite, mineral sands. Usually the total magnetic intensity of the earth’s magnetic field is measured and presented in units of nanoTeslas. Corrections for diurnal and secular variation are made to the data. Measurements can be obtained from fixed wing or helicopter airborne platforms; vehicle or pedestrian modes on the ground; and using a probe for drillhole data. GPS is used for positioning. Charts for the components and derivatives of the earth’s magnetic field can be obtained from the website at www.ngdc.noaa.gov/seg/potfld/geomag.shtml.

TABLE 1 Magnetic susceptibilities of various rocks Type

Range × 10

-5

Average × 10

Sedimentary

-5

Type

Range × 10

-5

Average × 10

Igneous

Dolomite

0-60

8

Granite

0-3200

Limestones

2-220

20

Rhyolite

20-2400

-

Sandstones

0-1320

25

Dolerite

80-2400

1100

Shales

4-1180

40

Augite-syenite

2200-2900

-

60

Olivine-diabase

Av. var. sed. (48)

0-3180

Metamorphic Amphibolite

Field Geologists’ Manual

-5

-

50

160

-

1600

Diabase

60-10300

3600

Porphyry

20-1300

4000

341

GEOPHYSICS

TABLE 1 Magnetic susceptibilities of various rocks (cont.) Type

Range × 10-5

Average × 10

-5

Metamorphic Schist

Range × 10

Type

95

Gabbro

60-5800

4800

20-11500

4800

40-8000

5600 8400

Phyllite

-

100

Basalts

Gneiss

8-1590

-

Diorite

-

280

Pyroxenite

-

Serpentinite

Average × 10

-5

Igneous 25-240

Quartzite

-5

200-1110

-

Peridotite

6100-12400

10300

Slate

0-2400

400

Andesite

-

10700

Av. var. met. (61)

0-4600

280

Av. acid igneous

2-5200

520

Av. basic igneous

35-7730

2070

Range × 10-5

Average × 10-5

TABLE 2 Magnetic susceptibilities of various minerals Type

Range × 10-5

Average × 10-5

Type

Graphite

-6

Siderite

80-250

Quartz

-1

Pyrite

3-330

Rock salt

-1

Limonite

175

Anhydrite, gypsum

-1

Arsenopyrite

190

Calcite

0.5- -1

Hematite

40-3000

440

190-7500

480

100-500000

100000

20000-250000

150000

100000-1000000

500000

Coal

2

Chromite

Clays

16

Franklinite

Chalcopyrite

25

Pyrrhotite

Sphalerite

48

Ilmenite

72

Magnetite

Cassiterite

100

29000

9.4. ELECTROMAGNETIC, RESISTIVITY AND INDUCED POLARISATION SURVEY METHODS AND TABLES ELECTROMAGNETIC METHODS The electromagnetic methods use the physical property of conductivity (this is the inverse of resistivity). Equipment is available which utilises either time-domain or frequency-domain principles. In both cases a particular parameter, or parameters, of the secondary electromagnetic field is measured, from which information regarding the rock types and structure is derived. Systems are available for airborne, ground and drillhole applications. Initially developed to find massive sulphide deposits, the EM method can now be applied to many other problems in mineral exploration, geotechnical, environmental and hydrogeological situations.

342

RESISTIVITY AND INDUCED POLARISATION METHODS The electrical method generally referred to as resistivity also uses the physical property of conductivity, but by convention the units used are those for resistivity, ie ohm.metres. Induced polarisation is an over-voltage phenomenon (a secondary effect) and may be measured in units of milliseconds, percentage frequency effect, or milliradians depending on the type of equipment being used. The resistivity/IP method can be applied on the ground and in drillholes. Magneto-metric resistivity (MMR) is a variation where it is the magnetic component of the secondary field which is measured. Resistivity/IP is generally applied in the search for disseminated sulphide mineralisation but also provides information for lithology and structure.

Field Geologists’ Manual

GEOPHYSICS

TABLE 1 Resistivities of minerals Mineral

Resistivity range Ωm

Formula -3

2 × 10 to 10

4

Resistivity average Ωm 1.7 × 10-3

Argentite

Ag2S

Bismuthinite

Bi2S2

18 to 570

---------

Covellite

CuS

3 × 10-7 to 8 × 10-5

2 × 10-5

Chalcocite Chalcopyrite Bornite Marcasite

Cu2S CuFeS2 Cu5FeS4 FeS2

-5

10-4

3 × 10 to 0.6 -5

4 × 10-3

-5

3 × 10-3

1.2 × 10 to 0.3 2.5 × 10 to 0.5 -3

5 × 10-2

10 to 3.5 -5

Pyrite

FeS2

2.9 × 10 to 1.5

3 × 10-1

Pyrrhotite

FemSn

6.5 × 10-8 to 5 × 10-2

10-4

Cinnabar

HgS

--------------------

2 × 107

-3

6

Molybdenite

MoS2

10 to 10

Galena

PbS

3 × 10-5 to 3 × 102

2 × 10-3

Millerite

NiS

--------------------

3 × 10-7

Stannite

Cu2FeSnS2

10-3 to 6 × 103

---------

Stibnite

Sb2S3

105 to 1012

5 × 106

Sphalerite

ZnS

1.5 to 10

10

7

-4

102 -1

Cobaltite

CoAsS

3.5 × 10 to 10

Smaltite

CoAs2

-------------------

5 × 10-5

Arsenopyrite

FeAsS

2 × 10-5 to 15

10-3

Niccolite

NiAs

-7

10 to 10

---------

-3

-6

2 × 10-5 -5

Sylvanite

AgAuTe4

4 × 10 to 2 × 10

Bauxite

Al2O3.nH2O

2 × 102 to 6 × 103

---------

Braunite

Mn2O3

0.16 to 1.2

---------

Cuprite

Cu2O

10-3 to 300

30

Chromite

FeCr2O4

1 to 106

---------

Specularite

Fe2O3

-----------------------

6 × 10-3

Hematite

Fe2O3

3.5 × 10-3 to 107

---------

Limonite

2Fe2O3.3H2O

103 to 107 -5

---------

--------3

Magnetite

Fe3O4

5 × 10 to 5.7 × 10

Ilmenite

FeTiO3

10-3 to 50

Wolframite

Fe,Mn,WO4

10 to 105

---------

Manganite

MnO(OH)

10-2 to 0.3

---------

Pyrolusite

MnO2

5 × 10-3 to 10 10

--------14

Quartz

SiO2

4 × 10

Cassiterite

SnO2

4 × 10-4 to 104

0.2

Rutile

TiO2

30 to 1000

500

Uraninite (Pitchblende)

UO2

1 to 200

---------

Anhydrite

CaSO4

--------------------

109

Calcite

CaCO3

---------------------

2 × 1012

Fluorite

CaF2

---------------------

8 × 1013

Siderite

Fe2(CO3)3

---------------------

70

Rock salt

NaCl

30 to 1013

---------

Field Geologists’ Manual

to 2 × 10

-----------------

---------

343

GEOPHYSICS

TABLE 1 Resistivities of minerals (cont.) Mineral

Resistivity range Ωm

Formula

1011 to 1012 10 to 1014 2 × 102 to 3 × 103 2 × 102 to 106 9 × 102 to 1014 2 × 102 to 106 1011 to 1012 0.6 to 105 10 to 1011 10-3 to 105 9 to 200 --------------------30 to 103 0.1 to 3 × 103 10 to 100 --------------------0.5 to 150 1 to 100 -------------------------------------------------------------

Sylvite KCl Diamond C Serpentinite Hornblende Mica Biotite Phlogopite Bituminous coal Coals (various) Anthracite Lignite Fire clay Meteoric waters Surface waters (ign. rocks) Surface waters (sediments) Soil waters Natural waters (ign. rocks) Natural waters (sediments) Sea water Saline waters, 3 per cent Saline waters, 20 per cent

Resistivity average Ωm ----------------------------------------------------------------------------------------30 ------------------------100 9 3 0.2 0.15 0.05

TABLE 2 Resistivities of various ores Ore

Resistivity Ωm

Other minerals

Gangue

2% (chalcopyrite)

80%

300

40%

20%

40%

130

60%

5%(ZnS) + 15%

20%

0.9

75%

10% (ZnS) + 5%

10%

0.14

95%

5% (ZnS)

Pyrite 19%

1.0

95%

5%

7.0

Pyrrhotite 41%

59%

2.2 × 10-4

58%

42%

2.3 × 10-4

79%

21%

1.1 × 10-5

95%

18%

8.5 × 10-5

95%

5%

1.4 × 10-5 4 × 13-3 to 3 × 107

SbS2 in quartz FeAsS 60%

FeS 20%

20% SiO2

10-4 to 10-2

FeAsS

3 × 10-3

Cu5FeS4 Cu5FeS4 40% (Fe,Mn)WO4 80%

344

0.39

60% SiO2

7 × 10-2 2 × 104

Field Geologists’ Manual

GEOPHYSICS

TABLE 2 Resistivities of various ores (cont.) Ore

Other minerals

(Fe,Mn)WO4

Resistivity Ωm

Gangue 3

10 to 107

CoAsS

7 × 10-2

PbS massive

0.8

PbS near massive PbS 50 - 80%

10-2 to 3

Fe2O3

0.1 to 300

Fe2O3

2.5 to 103 45

Iron Fe3O4 60% Fe3O4 from contact met.

0.5 to 102

Diss. brown iron oxide

8 × 102 to 3 × 106

75% brown iron oxide

2 × 104 to 8 × 105

25%

2.5 × 103

Fe2O3 fine grained Fe3O4

5 × 103 to 8 × 103

Fe3O4 in pegmatite

7 × 103 to 2 × 105

Zinc 30%

5% PbS, 15% FeS

0.75

50%

20

70%

3% chalco,17% PbS, 10% FeS

80%

10% PbS, 10% FeS

80%

2% chalco, 1% PbS, 2% FeS

15%

1.3

90%

5% PbS

5%

130

1.7 × 103

0.13

Graphitic slate

10-4 to 10-3

Graphite, massive

2 × 102 to 4 × 103

MoS2

1.6

MnO2, colloidal ore Cu2S

3 × 10-2

CuFeS2

10-4 to 1

CuFeS2, 80%

10% FeS

10%

0.66

CuFeS2, 90%

2% FeS

8% SiO2

0.65 103

FeCr2O4 FeCr2O4, 95%

1.2 × 104

5% serp.

TABLE 3 Resistivities of igneous and metamorphic rocks Resistivity range, Ωm

Rock type Granite Granite porphyry Feldspar porphyry Albite Syenite Diorite Diorite porphyry Porphyrite Carbonized porphyry

Field Geologists’ Manual

2

6

3 × 10 to 10 4.5 × 103 (wet) to 1.3 × 106 (dry) 4 × 103 (wet) 3 × 102 (wet) to 3.3 × 103 (dry) 102 to 106 104 to 105 1.9 × 103 (wet) to 2.8 × 104 (dry) 10 to 5 × 104 (wet) to 3.3 × 103 (dry) 2.5 × 103 (wet) to 6 × 104 (dry)

345

GEOPHYSICS

TABLE 3 Resistivities of igneous and metamorphic rocks (cont.) Resistivity range, Ωm

Rock type 2

5

3 × 10 to 9 × 10 2 × 104 to 2 × 106 (wet) to 1.8 × 104 (dry) 60 to 104 2 × 104 (wet) 4.5 × 104 (wet) to 1.7 × 102 (dry) 103 (wet) to 1.7 × 102 (dry) 20 to 5 × 107 102 to 5 × 104 103 to 106 10 to 1.3 × 107 (dry) 103 to 6 × 104 (wet) 3 × 103 (wet) to 6.5 × 103 (dry) 8 × 103 (wet) to 6 × 107 (dry) 20 to 104 2 × 103 (wet) to 105 (dry) 10 to 102 6 × 102 to 4 × 107 6.8 × 104 (wet) to 3 × 106 (dry) 102 to 2.5 × 108 (dry) 2.5 × 102 (wet) to 2.5 × 108 (dry) 10 to 2 × 108

Quartz porphyry Quartz diorite Porphyry (various) Dacite Andesite Diabase porphyry Diabase (various) Lavas Gabbro Basalt Olivine norite Peridotite Hornfels Schists (calcareous and mica) Tuffs Graphitic schists Slates (various) Gneiss (various) Marble Skarn Quartzites (various)

TABLE 4 Resistivities of metals and rocks Element

Resistivity range Ωm

Resistivity average Ωm

----------

4.5 × 10-7

Arsenic

----------

2.2 × 10

-7

Bismuth

----------

1.2 × 10-6

----------

1.7 × 10

-8

2.4 × 10

-8

Sulphur

10 to 10

10

-3

Tellurium

-4

10

-7

Tin

----------

1.1 × 10-7

Uranium

----------

3 × 10-7

Zinc

----------

5.8 × 10-8

Antimony

Copper Gold Graphite

----------7

5 × 10 to 10

Iron

----------

Lead

---------

2.2 × 10-7

----------

-7

Mercury

346

9.6 × 10

Element

Resistivity range Ωm

Resistivity average Ωm

Molybdenum

----------

5.7 × 10-8

Nickel

----------

7.8 × 10-8

Platinum

----------

10-7

Silver

----------

1.6 × 10-8

7

16

10 to 2 × 10

1014 -3

10-3

Field Geologists’ Manual

GEOPHYSICS

TABLE 5 Resistivities of sediments Resistivity range Ωm

Rock type Consolidated shales

20 to 103

Argillites

10 to 102

Conglomerates

2 × 103 to 104

Sandstones

1 to 6.4 × 108

Limestones

50 to 107 3.5 × 102 to 5 × 103

Dolomite Unconsolidated wet clay

20

Marls

3 to 70

Clays

1 to 100

Alluvium and sands

10 to 800

Oil sands

4 to 800

TABLE 6 Variation of rock resistivity with water content Rock Siltstone Siltstone Coarse grain ss Coarse grain ss Medium grain ss Medium grain ss Graywacke ss

% H 2O .54 .38 .39 .18

Resistivity Ωm 4

5.6 × 10

8

9.6 × 10

5

1.5 × 10

10

8

0.1

3 × 103

Peridotite

0

Pyrophyllite

0.76

Pyrophyllite

0

6 × 106 1011

Granite

0.31

4.4 × 103

0.1

1.4 × 10

Granite

0.19

1.8 × 106

4.7 × 10

3

Granite

0

4

Diorite

0.02

Diorite

0

6 × 106 4 × 104

1.16

Arkosic ss

1.0

1.4 × 103

11 1.3 0.96

0.6 × 10

3

1010 5.8 × 105

Basalt

0.095

6 × 10

3

Basalt

0

8 × 10

3

Olivine-pyroxenite

0.028

Olivine-pyroxenite

0

The effect of magnetic permeability on electrical measurements is very slight except in the case of concentrated magnetite, pyrrhotite and titanomagnetite.

1.3 × 108 2 × 104 5.6 × 107

TABLE 7 Magnetic permeabilities

MAGNETIC PERMEABILITIES

Field Geologists’ Manual

1.8 × 107

8

5.8 × 10

Dolomite

Peridotite

4.2 × 103

0.45

Dolomite

Resistivity Ωm

1.0

Graywacke ss Organic limestone

% H2O

Rock

Mineral

Permeability

Mineral

Permeability

Magnetite

5

Rutile

1.0000035

Pyrrhotite

2.55

Calcite

0.999987

Ilmenite

1.55

Quartz

0.999985

Hematite

1.05

Hornblende

1.00015

Pyrite

1.0015

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GEOPHYSICS

DIELECTRIC CONSTANTS OF ROCKS AND MINERALS The dielectric constant is a measure of the electrical polarisation resulting in an applied electric field. This polarisation may be molecular, electronic or ionic. The dielectric constant varies inversely with frequency. Most of the values given below have been made at

frequencies of 100 kHz or higher. The dielectric constant and conductivity of rock material are important considerations in Ground Penetrating Radar surveys.

TABLE 8 Dielectric constants of rocks and minerals Rock, mineral

Dielectric constant

Rock, mineral

Dielectric constant

Galena

18

Gypsum

5 to 11.5

Sphalerite

7.9 to 69.7

Beryl

5.5 to 7.8

Corundum

11 to 13.2

Biotite

4.7 to 9.3

Cassiterite

23

Epidote

7.6 to 15.4

Hematite

25

Orthoclase

3 to 5.8

Rutile

31 to 170

Plagioclase felspar

5.4 to 7.1

Fluorite

6.2 to 6.8

Quartz

4.2 to 5

Calcite

7.8 to 8.5

Zircon

8.6 to 12

Apatite

7.4 to 11.7

Granite (dry)

4.8 to 18.9

Barite

7 to 12.2

Gabbro

8.5 to 40

Peridote

8.6

Diorite

6.0

Norite

61

Serpentine

6.6

Quartz porphyry

14 to 49.3

Gneiss

8.5

Diabase

10.5 to 34.5

Sandstone (dry to moist)

4.7 to 12

Trap

18.9 to 39.8

Packed sand (dry to moist)

2.9 to 105

Dacite

6.8 to 8.2

Soil (dry to moist)

3.9 to 29.4

Obsidian

5.8 to 10.4

Basalt

12

Sulphur

3.6 to 4.7

Clays (dry to moist)

7 to 43

Rock salt

5.6

Petroleum

2.07 to 2.14

Anthracite

5.6 to 6.3

Water (20°C)

80.36

Ice

3 to 4.3

348

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GEOPHYSICS

9.5. RADIOMETRIC SURVEYS AND TABLES SURVEY METHODS The method utilises the gamma radiation emitted from the isotopes or daughter products of potassium, uranium and thorium. The principal applications are in the search for uranium, heavy mineral sands, alteration haloes and general geological mapping. The effective

penetration of gamma radiation is generally less than ten metres of regolith material. Instrumentation is available for airborne, ground and drillhole applications.

TABLE 1 Naturally occurring radioactive isotopes Element Potassium Calcium Vanadium Rubidium Indium Lanthanum Cerium Neodymium Samarium Samarium Samarium Gadolinium Lutecium Hafnium Rhenium Platinum Platinum Lead Thorium** Uranium** Uranium** * **

Isotope 40

19K 48 20Ca 50 23V 87 37Rb 115 49In 138 57La 142 58Ce 144 60Nd 147 62Sm 148 62Sm 149 62Sm 152 64Gd 176 71Lu 174 72Hf 187 75Re 190 78Pt 192 78Pt 204 82Pb 232 90Th 235 92U 238 92U

Abundance %

Half-life (years) 9

Type of radiation

Energy (MeV)

0.012

1.3 × 10

β, K-cap + γ*

1.46

0.18

f2 × 1016

β

0.12

0.24

6 × 1015

β, K-cap + γ*

0.17, 1.59

4.7 × 1010

β

0.27

27.8

β

0.60

1.1 × 1011

β, K-cap + γ*

0.54, 0.81, 1.43

11.1

--------

α

1.5

23.8

5 × 1015

α

1.8

14.97

1011

α

2.32

11.2

1.2 × 1013

α

2.14

13.8

~ 4 × 1014

α

1.84

0.2

1.1 × 1014

α

2.24

2.6

3 × 1010

β, γ

0.088, 0.20, 0.31

0.16

2 × 1015

95.72 0.089

6 × 10

14

α

2.5

10

β

p 0.008

0.013

6 × 1011

α

3.11

0.78

~1015

α

2.6

1.48

-------

α

------

62.9

100 0.72 99.3

7 × 10

1.39 × 1010

α,β,γ

0.03-2.62

8

α,β,γ

0.02-0.9

4.5 × 109

α,β,γ

0.4-2.5

7.1 × 10

K-electron capture followed by γ-ray emission. Each of these undergoes a long series of disintegrations yielding lead isotopes 208, 207, 206 respectively. During these disintegrations numerous γ-rays are emitted, in addition to the α-and β-particles.

Field Geologists’ Manual

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GEOPHYSICS

TABLE 2 Natural radioactive series of thorium and uranium Thorium series Element

Isotope

Half-life 10

1.4 × 10 yr

Decay constant sec

Thorium

90Th

232

Radium

88Ra

228

6.7 yr

3.3 × 10-9

Actinium

228 89Ac

6.1 yr

3.1 × 10-4

Thallium Lead

α, SF*, γ

0.059

--------

β, γ

0.03

--------

β, γ

0.06-0.97

f 10

1.91 yr

α, γ

0.085-0.214

5

3.64 day

2.2 × 10-6

α, γ

0.24, 0.29

--------

51 sec

1.3 × 10-2

α, γ

0.54

--------

0.16 sec

4.3

α

---------

--------

10.6 hr

1.8 × 10-5

β, γ

0.11-0.41

5

220 86Rn 216 84Po 212 82Pb 212 83Bi 212 84Po 208 81Tl 208 82Pb

Polonium

No. of γ-rays

224

Radon

Bismuth

γ-ray energies (MeV)

88Ra

1.15 × 10

-4

β, α, γ

0.04-2.2

f 10

0.3 × 10-6sec

2.3 × 106

α

---------

--------

3.1 min

3.7 × 10-3

β, γ

0.28-2.62

5

60.6 min

1.9 × 10

-8

Radiation

90Th

Radium

Lead

-18

228

Thorium

Polonium

1.58 × 10

-1

stable Actinium series

Uranium Thorium Protactinium Actinium Thorium Francium Radium Radon Astatine Polonium Astatine Bismuth Bismuth Polonium Lead Thallium Lead

350

92U

235

8

7.1 × 10 yr

3.1 × 10-17

α, SF*, γ

0.07-0.38

10

231

25.6 hr

7.4 × 10-6

β, γ

0.08-0.31

f 10

3.4 × 104yr

6.5 x 10-13

α, γ

0.29-0.36

f 10

90Th 231 91Pa 237 89Ac 227 90Th 223 87Fr 223 88Ra 219 86Rn 219 85At 215 84Po 215 85At 215 83Bi 211 83Bi 211 84Po 211 82Pb 207 81Tl 207 82Pb

-9

β, α, γ

0.09-0.19

9

18.2 day

4.35 × 10-7

α, γ

0.05-0.33

f 10

22 min

5.2 × 10-4

β, α, γ

0.05-0.31

4

11.7 day

6.76 × 10-7

α, γ

0.03-0.45

f 10

4 sec

0.17

α, γ

0.27, 0.4

--------

21.6 yr

10

α, β

--------

--------

1.8 × 10-3sec

3.8 × 102

α, β

--------

--------

10-4sec

6.9 × 103

α

--------

--------

8 min

1.44 × 10-3

β

--------

--------

2.15 min

5.35 × 10-3

α, β, γ

0.35

--------

54 sec

1.28 × 10

-2

0.52 sec

1.32

α,

0.56, 0.88

--------

36 min

3.2 × 10-4

β, γ

0.065-0.83

--------

4.8 min

2.4 × 10-3

β, γ

0.89

4

Stable

--------

--------

--------

--------

Field Geologists’ Manual

GEOPHYSICS

TABLE 2 Natural radioactive series of thorium and uranium (cont.) Element

Isotope

Half-life

Decay constant sec-1

Radiation

γ-ray energies (MeV)

No. of γ-rays

--------

Uranium Series Uranium Thorium Protactinium Uranium Thorium Radium Radon Polonium Astatine Radon Bismuth Polonium Lead Lead Bismuth Polonium Thallium Thallium Lead

92U

238

4.5 × 109yr

4.9 × 10-18

α, SF*, γ

0.048

234

24.1 day

3.3 × 10-7

β, γ

0.03-0.09

3

6.7 hr

2.84 × 10-5

β, γ

0.044-1.85

f 10

2.48 × 105yr

8.9 × 10-14

α, SF*, γ

0.053, 0.118

--------

2.75 × 10-10

α, γ

0.068-0.25

7

1622 yr

1.35 × 10

-11

α, γ

0.19-0.64

4

3.82 day

2.07 × 10-6

α, γ

0.51

--------

3.05 min

3.8 × 10-3

α, β

--------

--------

1.35 sec

0.51

α

--------

--------

0.03 sec

--------

α

0.61

--------

90Th 234 91Pa 234 92U 230 90Th 226 88Ra 222 86Rn 218 84Po 218 85At 218 86Rn 214 83Bi 214 84Po 214 82Pb 210 82Pb 210 83Bi 210 84Po 210 81Tl 206 81Tl 206 82Pb

4

8 × 10 yr

β, α, γ

0.45-2.43

f 10

1.64 × 10-4sec

4.2 × 103

α

--------

--------

26.8 min

4.3 × 10-4

β, γ

0.05-0.35

f 10

21 yr

1.05 × 10-9

β, γ

0.047

--------

5 day

1.58 × 10-6

β

--------

---------------

19.7 min

5.85 × 10

-4

α, γ

0.79

1.3 min

8.85 × 10-3

β, γ

0.3, 0.78, 1.1

--------

4.2 min

----------

β

--------

--------

138.4 day

5.7 × 10

-8

Stable

--------

SF* = spontaneous fission

TABLE 3 Radioactive minerals 1. Potassium minerals Mineral

Occurrence

Orthoclase and microline felspars [KAlSi3O8]

Main constituents in acid igneous rocks and pegmatites

Muscovite [H2KAl(SiO4)3]

Main constituents of acid igneous rocks and pegmatites

Alunite [K2Al6(OH)12SO4] Sylvite, carnallite [KCl, MgCl2 . 6H2O] Monazite [ThO2 + rare earth phosphate] Thorianite [(Th,U)O2] Thorite, uranothorite [ThSiO4 + U]

Field Geologists’ Manual

Alteration in acid volcanics Saline deposits in sediments 2. Thorium minerals Granites, pegmatites, gneiss Granites pegmatites, placers Granites, pegmatites, placers

351

GEOPHYSICS

TABLE 3 Radioactive minerals (cont.) 3. Uranium minerals Mineral

Occurrence

Uraninite [Oxide of U, Pb, Ra + Th, rare earths]

Granites, pegmatites and with vein deposits of Ag, Pb, Cu, etc.

Carnotite [K2O . 2UO3 . V2O5 . 2H2O]

Sandstones

Gummite [Uraninite alteration]

Associated with uraninite

TABLE 4 Background radiation in rocks and waters Rock

Ci/g (×10-12)

K (ppm)

Th (ppm)

U (ppm)

Hornblende Granite Basalts Olivine Ultramafics Marble Quartzite Sandstones Slates Dolomites Chalk Chondrites Fe meteorite

1.2 0.7-4.8 0.5 0.33

35 000 9000

15 2

4 0.6

10

0.2

0.05

850

0.08 0.015

0.02 0.04

1.9 5.0 2-4 3-8 8 0.4

Water (radium)

Ci/g (×10-12)

Saratoga, NY Bath, UK Carlsbad, Czech St. Lawrence River Valdemorillo, Spain Aix-les-Bains, France Manitou, CO Hot Springs, AR Atlantic Ocean Indian Ocean

0.01-0.1 0.14 0.04-0.1 0.00025 0.02 0.002 0.003 0.0009 0.014-0.034 0.007

Ci = curie; it is the activity that results in 3.7 × 1010 disintegrations per second.

9.6. SEISMIC SURVEY METHODS AND DATA SURVEY METHODS Longitudinal velocity, sometimes referred to as compressional velocity, is the physical property utilised by the seismic method. Acoustic impedance is the product of the rock velocity and density. Seismic refraction surveys generally have applications within the geotechnical field at depths of investigation ranging from 5 to 50 metres; but with a suitably large energy

source the method can be used for crustal studies. Seismic reflection surveys will supply structural and lithological information for depths ranging from 50 metres to many kilometres depending on the field parameters. Various corrections are applied to the data to refer it to a consistent datum plane. Surveys can be carried out on land surfaces and on water. Drillhole applications are also available.

TABLE 1 Compressional seismic wave velocities* Velocity( m/s) 200-400 400-1400 1400-1800 1800-2400 2400-3700 3700-4500 4500-6000

Rock description Soil, unconsolidated surface deposits Unconsolidated clays, silts, unsaturated sands, gravels Saturated sands and gravels; compact clays and silts; completely weathered rocks Consolidated sediments; probably water saturated; highly weathered/fractured metamorphic and igneous rocks; weathered and jointed sandstones and shales Shales, sandstones; weathered and/or sheared metamorphic and igneous rocks and limestones Slightly weathered and/or fractured igneous rocks; limestones; some very hard sandstone and shale Unweathered metamorphic and igneous rocks; some limestones and dolomite

* From Greenhalgh, S A, and Whitely, R J, 1977. Effective application of seismic refraction method to highway engineering projects, Australian Road Research, 7(1), March 1977.

352

Field Geologists’ Manual

GEOPHYSICS

Velocity (Vp) m/s

Rock type

330

Air

1400-1500

Water

3000-4000

Ice

300-1700

Alluvium, sand

1500-2600

Glacial moraine

2000-4500

Sandstones

2400-5000

Slates and shales

3500-6000

Limestones and dolomites

4000-5500

Rock salt

5000-6200

Granites and gneisses

5500-6300

Basalt

6400-6800

Gabbro

7500-8100

Dunite

7800-8400

Peridotite

9.7. DOWN-HOLE SURVEY METHODS All geophysical methods used on the surface can be modified and applied in drillholes. In mineral exploration those most commonly used are electromagnetic, induced polarisation/resistivity and magnetometric resistivity (MMR); and to a lesser extent magnetics, magnetic susceptibility and natural radioactivity. Geotechnical drillhole logs will include

electrical, natural gamma, sonic and a number of specialised variations to determine lithology, rock boundaries and structure. Additional methods may include borehole camera, caliper and temperature logs. The petroleum and coal industries routinely log exploratory wells and drillholes as an aid to lithological identification and cross-hole correlation.

9.8. AIRBORNE SURVEY METHODS Airborne magnetic and radiometric surveys are commonly used to define and delineate lithology and structures at an early stage in an exploration or mapping program. A regional survey may have a flight spacing of between 200 m and 500 m; detailed surveys may have a line spacing as close as 40 m. Modern instrumentation provides measurements on a virtually continual basis along the line. With magnetics, the total magnetic field is recorded; however, vertical and horizontal fields and gradients can be measured if required. Radiometric surveying conventionally records at least total count and the potassium, uranium and thorium channels, but the trend is towards recording the full radiometric spectrum.

Field Geologists’ Manual

Airborne electromagnetic surveying is usually applied as a detailed survey in the search for conductive bodies, but in some instances it is used on a regional basis for structural and lithological information. On a regional basis it may also be used for salinity studies. Airborne gravity is achieved from a fixed wing platform by measuring the gravity gradient rather than the direct acceleration of gravity Fixed wing or helicopter platforms are selected depending on the purpose of the survey and the local terrain conditions.

353

GEOPHYSICS

9.9. EARTHQUAKE MAGNITUDE AND INTENSITY

Vibrations produced by earthquakes are detected, recorded and measured on seismographs. From this data, the time, epicentre and focal depth of the earthquake can be determined and estimates can be made of the amount of energy that was released. The Richter Scale: When the earth quakes, the amplitude of the wave recorded on the seismograph is measured and then mathematically corrected to what the amplitude would have been if it had been recorded at a distance of 100 kilometres from the epicentre. The Richter magnitude derived from these corrected seismograph recordings indicates the amount of energy released as if it had been recorded at this standard 100 kilometre distance. On the Richter scale the magnitude varies logarithmically with the wave amplitude of the quake recorded by the seismograph. Each whole number step of magnitude represents an increase of ten times in the measured wave amplitude of an earthquake and an increase of 31 times in the amount of energy released. For example, the amplitude of an 8.3 magnitude earthquake is 10,000 times as large as a shock of magnitude 4.3. And a magnitude of 8.3 earthquake releases almost one million times more energy than one of magnitude 2.3. A quake of magnitude two on the Richter scale is the smallest quake normally felt by humans. Earthquakes with a Richter magnitude of seven or more are commonly considered to be major. The Richter magnitude scale has no fixed maximum or minimum; 1.

354

After Richter, C F, 1958. Elementary Seismology (Freeman: New York), in Kinemetrics, August, 1972.

1

observations have placed the largest recorded earthquakes in the world at about 8.9 and the smallest at about -3. Earthquakes with magnitudes smaller than two are called ‘micro-earthquakes’. Richter magnitudes are not used to estimate damage. The Modified Mercalli Intensity Scale: This scale measures the intensity of an earthquake’s effects in a given locality. It is based on actual observations of earthquake effects at specific places. The values range from I to XII. An earthquake can have only one magnitude but can have many intensities which decrease with distance from the epicentre. I

Not felt except by very few under especially favourable circumstances.

II

Felt by only a few persons at rest, especially on upper floors of buildings. Delicately suspended objects may swing.

III

Felt quite noticeably indoors, especially on upper floors of buildings, but many people do not recognise it as an earthquake. Standing motor cars may rock slightly. Vibration like passing of truck. Duration estimated.

IV

During the day felt indoors by many, outdoors by few. At night some awakened. Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked noticeably.

V

Felt by nearly everyone, many awakened. Some dishes, windows etc., broken; a few instances of cracked plaster; unstable objects overturned.

Field Geologists’ Manual

GEOPHYSICS

Disturbance of trees, poles and other tall objects sometimes noticed. Pendulum clocks may stop.

IX

Damage considerable in specially designed structures; well-designed frame structures thrown out of plumb; great in substantial buildings with partial collapse. Buildings shifted off foundations. Ground cracked conspicuously. Underground pipes broken.

VII Everybody runs outdoors. Damage negligible in buildings of good design and construction; slight to moderate in well built ordinary structures; considerable in poorly built or badly designed structures; some chimneys broken. Noticed by persons driving motor cars.

X

Some well built wooden structures destroyed; most masonry and frame structures destroyed with foundations; ground badly cracked. Rails bent. Landslides considerable from riverbanks and steep slopes. Shifted sand and mud. Water splashed (slopped) over banks.

VIII Damage slight in specially designed structures; considerable in ordinary substantial buildings, with partial collapse; great in poorly built structures. Panel walls thrown out of frame structures. Fall of chimneys, factory stacks, columns, monuments and walls. Heavy furniture overturned. Sand and mud ejected in small amounts. Changes in well water. Persons driving motor cars disturbed.

XI

Few, if any (masonry) structures remain standing. Bridges destroyed. Broad fissures in ground. Underground pipelines completely out of service. Earth slumps and land slips in soft ground. Rails bent greatly.

VI

Felt by all, many frightened and run outdoors. Some heavy furniture moved; a few instances of fallen plaster or damaged chimneys. Damage slight.

XII Damage total. Practically all works of construction are damaged greatly or destroyed. Waves seen on ground surface. Lines of sight and level are distorted. Objects are thrown upward into the air.

COMPARISON OF MAGNITUDE AND INTENSITY It is difficult to compare magnitude and intensity because intensity is linked with the particular ground and structural conditions of a given area, as well as

Richter magnitude

distance from the earthquake epicentre, while magnitude is a measure of the energy released at the focus of the earthquake.

Mercalli intensity

Effects

2

I-II

Usually detected only by instruments.

3

III

Felt outdoors.

4

V

Felt by most people, slight damage.

5

VI-VII

Felt by all; many frightened and run outdoors; damage minor to moderate.

6

VII-VIII

Everybody runs outdoors; damage moderate to major.

7

IX-X

Major damage.

8

X-XII

Total and major damage.

Field Geologists’ Manual

355

10. DRILLING 10.1. NOMINAL CORE AND HOLE DIAMETERS, AND VOLUMES PER FOOT AND PER METRE LENGTH 1.CONVENTIONAL DRILLING SIZES Nominal core diameter

Size

1

Nominal core volume Nominal hole diameter Nominal hole volume per m per m per ft per ft length length length length (m3 × 10-3) (cu in) (Imp gal) (litre) (cu in) (inch) (mm)

(inch)

(mm)

XRT

0.735

18.7

5.1

0.27

1.175

29.8

13.0

0.047

0.70

EX, EXM2, EWM

0.845

21.5

6.7

0.36

1.485

37.7

20.8

0.075

1.12

EXT

0.905

23.0

7.7

0.42

1.485

37.7

20.8

0.075

1.12

E17 AX, AXM2, AWM

0.968

24.6

8.8

0.47

1.485

37.7

20.8

0.075

1.l2

1.185

30.1

13.2

0.71

1.890

48.0

33.7

0.121

1.81

AXT

1.280

32.5

15.4

0.83

1.890

48.0

33.7

0.121

1.81

A17

1.310

33.3

16.2

0.87

1.890

48.0

33.7

0.l21

1.81

BX, BXM, BWM NX, NXM, NXMS, NWM

1.655

42.0

25.8

1.39

2.360

59.9

52.5

0.189

2.82

2.155

54.7

43.8

2.35

2.980

75.7

83.7

0.302

4.50

AM3, AMS3

1.032

26.2

10.0

0.54

1.890

48.0

33.7

0.121

1.81

BM, BMS3

1.281

32.5

15.5

0.83

2.360

59.9

52.5

0.189

2.82

NM3, NMS3

1.862

47.3

32.7

1.76

2.980

75.7

83.7

0.302

4.50

AMLC2

1.062

27.0

10.6

0.57

1.890

48.0

33.7

0.121

1.81

BMLC

1.386

35.2

18.1

0.97

2.360

59.9

52.5

0.189

2.82

NMLC

2.045

51.9

39.4

2.12

2.980

75.7

83.7

0.302

4.50

HMLC

2.50

63.5

58.9

3.17

3.874

98.4

141.4

0.510

7.60

A19DT

1.156

29.4

l2.6

0.68

1.890

48.0

33.7

0.121

1.81

A19TT

1.062

27.0

10.6

0.57

1.890

48.0

33.7

0.121

1.81

B19DT

1.565

39.8

23.1

1.24

2.360

59.9

52.5

0.189

2.82

B19TT

1.500

38.1

21.2

1.14

2.360

59.9

52.5

0.189

2.82

N19DT

2.095

53.2

41.4

2.22

2.980

75.7

83.7

0.302

4.50

N19TT

2.045

51.9

39.4

2.12

2.980

75.7

83.7

0.302

4.50

H19DT

2.500

63.5

58.9

3.17

3.783

96.1

134.9

0.486

7.25

H19TT

2.406

61.1

54.6

2.93

3.783

96.1

134.9

0.486

7.25

P19DT2

3.369

85.6

107.0

5.75

4.835

122.8

220.3

0.794

11.85

P19TT2

3.275

83.2

101.1

5.43

4.835

122.8

220.3

0.794

11.85

2

1. 2. 3.

The nominal core diameter is the manufacturers standard bit inside diameter, and the nominal hole diameter is the manufacturers standard reamer shell outside diameter—supplied by Mindrill Limited. Rare. Obsolete.

Field Geologists’ Manual

357

DRILLING

2. WIRELINE DRILLING SIZES Nominal core diameter Size

3

(inch)

(mm)

1

Nominal core volume

Nominal hole diameter

per ft length (cu in)

per m length 3 -3 (m × 10 )

(inch)

(mm)

Nominal hole volume per ft per m length length (cu in) (Imp gal) (litre)

AXWL

0.938

23.8

8.3

0.45

1.890

48.0

33.7

0.121

1.81

BXWL3

1.315

33.4

16.3

0.88

2.360

59.9

52.5

0.189

2.82

NXWL3

1.718

43.6

27.8

1.50

2.980

75.7

83.7

0.302

4.50

AQ, AQU

1.062

27.0

10.6

0.57

1.890

48.0

33.7

0.121

1.81

BQ, BQU

1.433

36.5

19.3

1.04

2.360

60.0

52.5

0.189

2.82

NQ, NQU

1.875

47.6

33.1

1.78

2.980

75.8

83.7

0.302

4.50

HQ

2.500

63.5

58.9

3.17

3.783

96.1

134.9

0.486

7.25

PQ2

3.345

85.0

105.4

5.67

4.828

122.6

219.7

0.792

11.81

BXHR3

1.595

40.5

24.0

1.29

2.360

59.9

52.5

0.189

2.82

NXHR3

2.095

53.2

41.4

2.22

2.980

75.7

83.7

0.302

4.50

BQ3

1.320

33.5

16.4

0.88

2.360

59.9

52.5

0.189

2.82

NQ3

1.775

45.1

29.7

1.60

2.980

75.7

83.7

0.302

4.50

HQ3

2.406

61.1

54.6

2.93

3.783

96.1

134.9

0.486

7.25

PQ3

3.270

83.1

100.8

5.42

4.828

122.6

219.7

0.792

11.81

A18DT2

1.156

29.4

12.6

0.68

1.890

48.0

33.7

0.121

1.81

A18TT2

1.062

27.0

10.6

0.57

1.890

48.0

33.7

0.121

1.81

B18DT

1.565

39.8

23.1

1.24

2.360

59.9

52.5

0.189

2.82

B18TT

1.500

38.1

21.2

1.14

2.360

59.9

52.5

0.189

2.82

N18DT

2.095

53.2

41.4

2.22

2.980

75.7

83.7

0.302

4.50

N18TT

2.045

51.9

39.4

2.12

2.980

75.7

83.7

0.302

4.50

H18DT

2.500

63.5

58.9

3.17

3.783

96.1

134.9

0.486

7.25

H18TT

2.406

61.1

54.6

2.93

3.783

96.1

134.9

0.486

7.25

P18DT2

3.369

85.6

107.0

5.75

4.835

122.8

220.3

0.794

11.85

P18TT2

3.275

83.2

101.1

5.43

4.835

122.8

220.3

0.794

11.85

CHD76

1.713

43.5

27.7

1.49

2.98

75.7

83.7

0.302

4.50

CHD101

2.50

63.5

58.9

3.17

4.0

101.3

150.8

0.544

8.06

CHD134

3.346

85.0

105.5

5.67

5.276

134.0

262.3

0.946

14.10

LTK46

1.40

35.6

18.5

0.99

1.819

46.2

31.2

0.137

1.68

LTK56

1.78

45.2

29.9

1.60

2.217

56.3

46.3

0.204

2.49

1. 2. 3.

358

The nominal core diameter is the manufacturers standard bit inside diameter, and the nominal hole diameter is the manufacturers standard reamer shell outside diameter—supplied by Mindrill Limited. Rare. Obsolete.

Field Geologists’ Manual

Field Geologists’ Manual

60

58

56

43

48

Collar

50

100

160

250

026

028

032

031

030

c Bng (mag)

356

358

002

001

360

255

205

130

75

25

e Hole depth for calc.1

50

75

55

50

25

f Hole length for calc.

Elevation calculation

4NW

2NW

2 NE

1 NE

0

–0.7431

–0.7986

–0.8290

–0.8480

–0.8660

–37,2

–59.9

–45.6

–42.4

–21.6

998.0

1035.2

1095.1

1140.7

1183.1

+1204.7

j g i h Bearing Sin dip Differ- Elevation for ence in angle calc.2 elevation (±)

Conversion of survey data

d Bng (grid)

0.6691

0.6018

0.5592

0.5299

0.5000

k Cos dip angle

33.46

45.14

30.76

26.50

12.50

0.9976

0.9994

0.9994

0.9998

1.0000

0.0698

0.0349

0.0349

0.0175

0.0000

n Sin bng (sin g)

+33.4

+45.1

+30,7

+26.5

+12.5

o Northing ± (1 × m)

Calculation of coordinates m l Cos Horiz. bng advance (f × k) (cos g)

–2.3

–1.6

+1.1

+0.5

–

p Easting ± (1 × n)

1412.2

1378.8

1333.7

1303.0

1276.5

1264.0

North (± ο)

4829.7

4832.0

4833.6

4832.5

4832.0

4832.0

East (± p)

Coordinates

See also Wilson, G J, 1968. New ways to compute directional surveys, World Oil, November 1968: 107-109.

2. For the calculation, when the grid bearing (d) is 0 to 90° use grid bearing ( +N, +E) when the grid bearing (d) is 90° to 180°, use 180°—grid bearing (–N, +E) when the grid bearing (d) is 180° to 270°. use grid bearing —180° ( –N, –E) when the grid bearing (d) is 270° to 360°, use 360°—grid bearing (+N, –E)

to half way to the next. The coordinates and elevation of the lower half way point are calculated (See example above).

1. Calculation is based on the tangential method, in which the drillhole survey measurements are assumed to be the average values for a hole length from half way to the previous survey

255 TD

b Dip angle (±)

Survey data

a Hole depth

10.2.1. CALCULATION OF DRILLHOLE ELEVATIONS AND COORDINATES FROM DOWN-HOLE SURVEYS

DRILLING

359

DRILLING

10.2.2. ESTIMATION OF HOLE DIP FROM ACID TUBE SURVEYS

For a more convenient estimation of hole dip angle use a Bon Goniometer, or a Thompson-Cumming true dip etch reader, available from J K Smit and Sons International Limited.

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DRILLING

10.3. DETERMINATION OF TRUE WIDTH FROM OBLIQUE DRILLHOLE INTERSECTION 1. GRAPHICAL SOLUTION Given:

Planar target formation: Strike Direction True Dip

= 040° =60° towards 130° (S.E.)

Drillhole intersection: Hole Bearing Hole Dip Angle Intersection Width

= 270° or 40° off true dip line (130 = 310) = 45° = 10.0 units

Solution (Refer to diagram): Approach: Rotation of vertical planes to horizontal plane. This solution is a simple extension of the standard geometric rotation to determine either true or apparent dip given one or the other and strike directions (ie triangles ABC, ACD and ADE). AB = Oblique intersection = 10.0 units. ∴ Point A is pierce point into target plane, CD is strike of target formation. Construction Procedure: (Select suitable scale for plotting, accuracy and ease of measurement.) i.

Triangle ABC in vertical plane of drillhole to show entry dip angle CAB (45°) and oblique intersection AB.

ii.

Triangle ACD in horizontal plane with angle CAD = 40° being angle between true dip and intersection planes, and angle CDA = 90°.

iii. Triangle ADE in vertical plane of true dip with angle ADE = 90°, and DE = BC. Join AE which represents foreshortened intersection AB viewed normal to true dip plane. AE = approximately 8.9 units. iv.

Extend AD to F such that angle AFE = true dip of 60° and FE passes through point E.

v.

Triangle AFE in the vertical plane shows true dip with FE representing the lower side of the target plane. Construct a perpendicular from point A (pierce point of target plane) to FE at point G. GA = true width of target formation, and length GA = approximately 8.2 units.

(Provided by D R Cheeseman, July 4, 1974.)

Field Geologists’ Manual

2. MATHEMATICAL SOLUTION T a b c

= true thickness = dip of drillhole (45°) = dip of formation (60°) = angle between direction of dip and direction of hole (40°) AB = drillhole intercept (10 units) T = AB (sin a × cos b − cos a × sin b × cos c) = 10 (0.707 × 0.500 − 0.707 × 0.866 × −0.766) = 10 (0.353 + 0.469) = 8.22 See also Peele, R, 1945. Mining Engineers’ Handbook, 3rd edition, Vol 1, pp 9-68, 9-69 (John Wiley: New York).

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10.4. CHECK LISTS FOR DRILLHOLE LOGGING PETROLEUM WELLS For petroleum exploration and production wells, a standard Composite Well Log format has been established by the Bureau of Mineral Resources. This lists all the status and location data at the beginning, then describes in a series of columns: Drilling rate, drilling activity, lithology (graphic column presentation), depth, hydrocarbon analysis data; spontaneous potential, resistivity, gamma ray and neutron logs, lithologic descriptions; casing, plugs and deviation information; and stratigraphic position (stage and series).

MINERAL EXPLORATION DRlLLHOLFS For mineral exploration drillholes, no standard exists. Information recorded on the top of the first page of the drill log is generally hole number; name of the prospect, mine, etc; location—both grid coordinates and cadastral position; elevation of hole collar; hole direction and inclination; total depth; size of hole and core in depth ranges; depths of casing used; date of start and completion of drilling; name of the person logging core or cuttings; and page number—often as sheet.…of…. Subsequent pages generally show only the hole number and page number.

(in metres and millimetres); and calculated per cent core recovered; a list of assays; a graphic lithological section; lithology—degree of weathering, colour, grain size, field rock name (often in capitals or underlined), proportions of rock minerals, attitude of bedding or foliation ( the angle between the planar structure and the long axis is generally stated, often termed θ), attitude and spacing of joints; and attitude, width and description of sheared zones. The interval in which ore minerals are present is listed separately, with ore mineral species in capitals or underlined, and with notes on weathering, grain size, grain relationships, orientation of ore minerals and of zones of mineralisation, gangue minerals present, their grain size and relation to the ore minerals, and a visual estimate of grade as per cent metal. Non-coring drillholes For non-coring drillholes, the same general location information is provided, with data on the bit diameters or baler diameters used for each section drilled. Recovery of cuttings is shown as volume recovered for a stated interval, and per cent recovery calculated for the theoretical volume which should be recovered for that hole diameter. Surveys and summary

Diamond drillholes For diamond drillholes, the range of data shown is generally length of coring run, in metres and millimetres, as defined by the driller’s core blocks; length drilled; measured length of core recovered

362

Drillhole surveys are generally listed at the end of the lithological-mineralisation log, and a summary of the log listing the intervals of various major lithological units, and the intervals of economic mineralisation as average grades above a selected minimum grade.

Field Geologists’ Manual

11. MISCELLANEOUS 11.1. ADDRESSES OF AUSTRALASIAN GEOLOGICAL SURVEYS AND UNIVERSITIES WITH GEOSCIENCE DEPARTMENTS Australian Capital Territory Australian Geological Survey Organisation, GPO Box 378, Canberra , ACT 2601. Dept of Geology, and Research School of Earth Sciences, Australian National University, Canberra ACT 0200. Dept of Geology, Faculty of Applied Science, University of Canberra, PO Box 1, Belconnen, ACT 2616. New South Wales Geological Survey of New South Wales, Dept of Mineral Resources, PO Box 536, St Leonards, NSW 2065. Dept of Geology and Geophysics, University of New England, Armidale, NSW 2351. Dept of Geology, University of Newcastle, Callaghan, NSW 2308. Dept of Applied Geology, University of New South Wales, PO Box 1, Kensington, NSW 2033. Dept of Applied Geology, University of Technology, PO Box 123, Broadway, NSW 2007. Dept of Earth and Planetary Sciences, Macquarie University, North Ryde, NSW 2109. Dept of Geology and Geophysics, University of Sydney, Sydney, NSW 2006. School of Geosciences, University of Wollongong, Wollongong, NSW 2522. Faculty of Resource Science and Management, Southern Cross University, PO Box 157, Lismore NSW 2480.

Dept of Geology, University of South Australia, Smith Road, Salisbury East, SA 5109. School of Earth Sciences, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001. Dept of Applied Geology, Gartrell School of Mining, Metallurgy and Applied Geology, University of South Australia, Ingle Farm SA 5095. Tasmania Mineral Resources Tasmania, PO Box 56, Rosny Park, Tas 7018. Dept of Geology, University of Tasmania, GPO Box 252 C, Hobart, Tas. 7001. Victoria Geological Survey of Victoria, Dept of Natural Resources and Energy, PO Box 500, East Melbourne, Vic 3001. Department of Geology, Latrobe University College of Advanced Education, PO Box 199, Bendigo, Vic 3550. School of Earth Sciences, Latrobe University, Bundoora, Vic 3083. Dept of Geology, Ballarat University College, PO Box 663, Ballarat, Vic 3353. School of Earth Sciences, University of Melbourne, Parkville, Vic 3052. Dept of Earth Sciences, Monash University, Clayton, Vic 3168. Dept of Civil and Geological Engineering, Royal Melbourne Institute of Technology, GPO Box 2476V, Melbourne, Vic 3001.

Queensland Geological Survey of Queensland, Dept of Mines and Energy, GPO Box 194, Brisbane Qld 4001. School of Earth Sciences, James Cook University of North Queensland, Townsville, Qld 4811. James Cook University, Cairns campus, PO Box 6811, Cairns, Qld 4870. James Cook University, Mackay campus, PO Box 301, Mackay, Qld 4740. Dept of Earth Sciences, The University of Queensland, St Lucia, Qld 4072. School of Geology, Queensland University of Technology, GPO Box 2434, Brisbane Qld 4001.

Western Australia Geological Survey of Western Australia, 100 Plain St, Perth, WA 6004. Dept of Mineral Science, Murdoch University, South St, Murdoch WA 6150. Dept of Mineral Exploration and Mining Geology, Western Australian School of Mines, Curtin University, Kalgoorlie, PO Box 597, Kalgoorlie, WA 6430. School of Applied Geology, Curtin University (Perth), GPO Box U1987, Perth, WA 6001. Dept of Geology and Geophysics, University of Western Australia, Nedlands, WA 6009.

South Australia Mineral Resources Group, Primary Industries and Resources South Australia, GPO Box 1671, Adelaide, SA, 8001. Dept of Geology and Geophysics, The University of Adelaide, Adelaide, SA 5005.

Field Geologists’ Manual

New Zealand New Zealand Institute of Geological and Nuclear Sciences Ltd, PO Pox 30-368, Lower Hutt, New Zealand.

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MISCELLANEOUS

Dept of Geology, University of Auckland, Private Bag 92019, Auckland, NZ. Dept of Geology, University of Canterbury, Private Bag 4800, Christchurch, NZ. Dept of Geology, University of Otago, PO Box 56, Dunedin, NZ. Dept of Earth Sciences, University of Waikato, Private Bag 3105, Hamilton, NZ. Department of Geology, Victoria University of Wellington, PO Box 600, Wellington, NZ.

Papua New Guinea Geological Survey of Papua New Guinea, PO Box 778, Port Moresby, PNG. Geology Dept, The University of Papua New Guinea, Box 414, University PO NCD, Port Moresby, PNG. Dept of Mining Engineering, The Papua New Guinea University of Technology, Private Mail Bag, Lae, PNG.

11.2. SAFETY PRECAUTIONS ON ENTERING OLD WORKINGS SAFETY EQUIPMENT Hard hat. Cap lamp. Long trousers. Steel-toed boots. Eye protectors. Safety belt. Lengths of rope should be available on surface. Matches and candle.

SHAFTS Check for collapse of ground surrounding the shaft collar (coning effect). Check condition of timber at shaft collar, eg rotten, split. Test thoroughly and carefully any decking covering a shaft. Check for loose concrete slabs at the collar of a concrete lined shaft. Clear loose rocks and any movable objects away from shaft collar, so there is no possibility of them being knocked down the shaft. Check headframe for any loose timber, etc, that may fall. Watch for flooded creeks which could swell and flood shaft. It is bad policy to explore unknown mines in stormy weather. Check state of shaft immediately below collar—rotten or split timber, loose ground, loose timber. Check for spiders, snakes, wasps, etc.

LINES OF COMMUNICATION Never enter an old mine alone. Always ensure there is someone on the surface to initiate a rescue operation.

1

Always tell someone where you are going. If the mine is large, mark the walls for guides on the return journey.

LADDERWAYS There are three points of contact on the ladder. Grasp the rungs, not the sides of the ladder. Check the condition of all ladders you use—rust, rotten timber, missing rungs. Check the ladder anchorage—rust in metal clogs, attached to rotten timber, unsafe landings—if unsure use a safety belt. Check ground and timber around you as you descend—loose timber and stones. Beware of loose stones on landings as they can cause you to slip. Wherever possible remove hazards for people following you. Never look upwards unless you are wearing eye protection, and then only if necessary. If you are following someone be careful not to knock objects onto him. Descend slowly and be careful of poor foothold space between rungs and wall. Always make sure there is a ladder beneath you.

OVERHEAD Loose stones in back—check by sight and sound. Watch for slabbing on the walls. Check that old sets are still properly blocked and dogged. Don’t follow anyone up a muck pile—wait for him to reach the top before you ascend. Watch for hang-ups in chutes and ore passes. Beware of protruding pipes and pieces of wire at eye level.

UNDERFOOT 1.

364

From Burford, J, 1971. Metalliferous mines-safety precautions on entering old workings. Qld Govt Min Jour, November 1971, by permission.

Watch for open holes—winzes, chutes, ore passes. Watch for sumps under water.

Field Geologists’ Manual

MISCELLANEOUS

Beware of wet slime used for filling, it could retain its moisture content. Rope off any sections of the mine that you consider unsafe. Check for snakes which may have fallen down shaft. Pools of water covered by boards may indicate a winze. Test all boards over pools of water before walking on them.

(ii) will cause a person to breathe more heavily and deeply; (iii) when breathed in large quantities, it may cause a distinctly acid taste. Carbon monoxide (a)

Colourless, odourless, tasteless gas. It is very poisonous in extremely low concentrations, eg concentrations over 1000 ppm cause unconsciousness, respiratory failure, and death if exposure is continued for more than one hour. It is explosive in air.

(b)

Sources of CO:

GASES The possibility of striking gases is greater in old workings where ventilation circuits may have broken down and dangerous concentrations of these gases have been allowed to collect, especially in deadend drives, raises and winzes.

(a)

Air deficient in oxygen becomes dangerous when O2 concentration falls below 16 per cent. Normal air concentration is 21 per cent.

(b)

Oxygen depletion is caused by

(c)

dilution by other gases;

(iii) ground water, depleted of its own oxygen, absorbing oxygen from the atmosphere; (iv) timber decay which is due to fungus growth requiring O2. The action is accelerated by hot humid air and crushed timber. A candle or match flame will be extinguished when O2 concentration falls below 17 per cent;

(ii) Breathing will become faster at 17 per cent oxygen concentration. At 15 per cent concentration dizziness, headaches and buzzing in the ears should occur.

Hydrogen sulphide (H 2 S) (a)

A very poisonous gas, but rarely found in mines. Often found with stagnant waters. H2S is very soluble and may be liberated in dangerous quantities by stirring up stagnant waters in traversing old mine workings.

(b)

Sources of H2S: (i)

(b)

Methane (CH 4 ) (a)

Colourless, odourless gas. Non-explosive in air. It is heavier than air and will be found near the floor where the air is still.

Can be found in metalliferous mines. Colourless, odourless, tasteless gas. Explosive in air within a certain range of concentrations—set off by open flame. It is lighter than air—usually found near the back.

(b)

Source—decaying of old timbers.

Sources of CO2:

(c)

Tests:

(i)

(i)

Mine fires, eg slow combustion of timber in an abandoned mine;

(iii) Oxidation of carbonate ores. Tests: (i)

Oxides of nitrogen (NO, NO 2 ) (a)

will extinguish a candle flame;

Field Geologists’ Manual

No direct effect on men but may replace O2 in air;

(ii) Davey safety lamp, Drager tube.

(ii) Blasting; (c)

Action of acid water on sulphide ore;

(ii) Reducing action of bacteria in acid water.

Carbon dioxide (a)

The gas will cause headaches, quickly followed by staggering, confusion of mind, nausea and finally death. High concentrations will give no forewarnings before collapsing;

(ii) There is no method of detecting CO without the use of an instrument, eg, Drager Multigas Detector.

Tests for oxygen depletion: (i)

Tests: (i)

(ii) sulphide minerals and carbonaceous shales oxidising slowly;

(c)

Mine fires;

(ii) Blasting operations.

Oxygen

(i)

(i)

Small concentrations can cause death. Enough NO2 to produce irritation in nose and air passages

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MISCELLANEOUS

is very dangerous. Its effect on these passages may not be felt until several hours after contact and even then may result in death.

(b)

Source—results from fires in sulphide ore bodies.

(c)

Tests:

(b)

Source of NO and NO2—formed by partial detonation of explosives.

(i)

(c)

Tests:

(ii) Suffocating pungent odour.

(i)

Odour (similar to burnt powder);

(ii) NO2 has a reddish colour. (NO immediately goes to NO2 on contact with oxygen). Sulphur dioxide (SO 2 ) (a)

Detected by irritating effect on eyes and respiratory passages;

Very poisonous and colourless. Has a pungent sulphurous odour.

SAMPLING Use eye protectors. While sampling watch for nearby effects—loosening of pieces overhead, slabbing on walls. Do not sample shatter points caused by explosives or around old drill holes. Small quantities of explosives remaining could be detonated by a hammer blow.

11.3. RADIO ALPHABET Letter

Word

Spoken as*

Letter

Word

Spoken as*

A

ALFA

AL FAH

N

NOVEMBER

NO VEM BER

B

BRAVO

BRAH VOH

O

OSCAR

OSS CAH

C

CHARLIE

CHAR LEE

P

PAPA

PAH PAH

D

DELTA

DELL TAH

Q

QUEBEC

KE BECK

E

ECHO

ECK OH

R

ROMEO

ROW ME OH

F

FOXTROT

FOKS TROT

S

SIERRA

SEE AIR RAH

G

GOLF

GOLF

T

TANGO

TANG GO

H

HOTEL

HOH TELL

U

UNIFORM

YOU NEE FORM

I

INDIA

IN DEE AH

V

VICTOR

VICK TAH

J

JULIETT

JEW LEE ETT

W

WHISKEY

WISS KEY

K

KILO

KEY LOH

X

X-RAY

ECKS RAY

L

LIMA

LEE MAH

Y

YANKEE

YANG KEY

M

MIKE

MIKE

Z

ZULU

ZOO LOO

* The syllables to be emphasised are in bold type.

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11.4.1. TIME OF BEGINNING AND END OF DAYLIGHT FOR THE SOUTHERN HEMISPHERE

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MISCELLANEOUS

11.4.2. SEVENTY YEAR LETTER CALENDAR

The Letter opposite each of the 70 years in the Index indicates the Calendar required for that year. Thus, if the year sought is 1978, use Calendar A; 1992, L; 2010, F and so on. Asterisk alongside year indicates Leap Year.

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MISCELLANEOUS

11.5.1. GRAPH PAPER, MILLIMETRE RULING

370

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11.5.2. TRIANGULAR GRAPH PAPER

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11.6. OCCUPATIONAL HEALTH AND SAFETY THE AusIMM STATEMENT At its meeting on 27 September 1996, Council approved the following statement of the principles which members must observe as professionals working in the minerals industry. Council noted that this topic had been discussed in depth at the Branch Representatives Meeting in Perth in March 1996 and that it reflects the need expressed by many members for guidance as to the ethical requirements and their responsibilities with respect to the Environment and Safety and Health. Statement: The Institute expects and encourages each of its members to work for the welfare of present and future generations, in particular in the areas of the environment, safety and health, Therefore, The Institute:

• Expects members to acquire and maintain the level of knowledge required to meet their environmental, safety and health responsibilities in all aspects of their professional activities and, within their areas of competence, to practise and promulgate appropriate procedures to meet these responsibilities.

• Encourages members, within their areas of competence, to assist the industry, governments and the community by contributing relevant expertise to

372

discussions of risk assessment as well as the costs and benefits associated with environmental and safety and health issues.

• Expects members, as a minimum, to comply with applicable laws and regulations and to have due regard to sound practice in environmental and safety and health management. The Institute will assist members to acquire knowledge and to develop their understanding of these topics through its programs of Conferences and its Publications. SELECTED BIBLIOGRAPHY Anon, 1989. Drilling Safety and First Aid (Australian Drilling Industry Training Committee: Sydney). Anon, 1991. Survival—Remote Area First Aid (St John Ambulance: Forrest, WA). Anon, 1992. Planning for Field Safety (American Geological Institute: Alexandria, VA). Anon, 1998. Exploration Safety Guidelines (Queensland Dept of Mines and Energy: Brisbane). Dunlevy, M, 1981. Stay Alive—A Handbook on Survival (Australian Government Publishing Service: Canberra). Mills, D, 1996. Travelling Well—The Essential Handbook for Healthy Travel (Traveller’s Medical and Vaccination Centre: Brisbane). Radusin, S (Ed), 1992. Australian Bush Survival Skills and Search Rescue Manual (Start Publishing: Cannington, WA).

Field Geologists’ Manual

12. MATHEMATICAL TABLES AND CONVERSION FACTORS 12.1. TRIGONOMETRIC FUNCTIONS Deg. 0

sin .0000

cos 1.000

tan .0000

1 2 3 4

.0175 .0349 .0523 .0698

.9998 .9994 .9986 .9976

.0175 .0349 .0524 .0699

5 6 7 8 9

.0871 .1045 .1219 .1392 .1564

.9962 .9945 .9925 .9903 .9877

10 11 12 13 14

.1736 .1908 .2079 .2250 .2419

15 16 17 18 19

sec 1.0000

cot ∞

57.30 28.65 19.11 14.34

1.0002 1.0006 1.0014 1.0024

57.29 28.64 19.08 14.30

.0875 .1051 .1228 .1405 .1584

11.474 9.5668 8.2055 7.1853 6.3925

1.0038 1.0055 1.0075 1.0098 1.0125

11.43 9.5144 8.1443 7.1154 6.3138

.9848 .9816 .9781 .9744 .9703

.1763 .1944 .2126 .2309 .2493

5.7588 5.2408 4.8097 4.4454 4.1336

1.0154 1.0187 1.0223 1.0263 1.0306

5.6713 5.1446 4.7046 4.3315 4.0108

.2588 .2756 .2924 .3090 .3256

.9659 .9613 .9563 .9511 .9455

.2679 .2867 .3057 .3249 .3443

3.8637 3.6280 3.4203 3.2361 3.0716

1.0353 1.0403 1.0457 1.0515 1.0576

3.7321 3.4874 3.2709 3.0777 2.9042

20 21 22 23 24

.3420 .3584 .3746 .3907 .4067

.9397 .9336 .9272 .9205 .9135

.3640 .3839 .4040 .4245 .4452

2.9238 2.7904 2.6695 2.5593 2.4586

1.0642 1.0711 1.0785 1.0864 1.0946

2.7475 2.6051 2.4751 2.3559 2.2460

25 26 27 28 29

.4226 .4384 .4540 .4695 .4848

.9063 .8988 .8910 .8829 .8746

.4663 .4877 .5095 .5317 .5543

2.3662 2.2812 2.2027 2.1301 2.0627

1.1034 1.1126 1.1223 1.1326 1.1434

2.1445 2.0503 1.9626 1.8807 1.8040

30 31 32 33 34

.5000 .5150 .5299 .5446 .5592

.8660 .8572 .8480 .8387 .8290

.5774 .6009 .6249 .6494 .6745

2.0000 1.9416 1.8871 1.8361 1.7883

1.1547 1.1666 1.1792 1.1924 1.2062

1.7321 1.6643 1.6003 1.5399 1.4826

35 36 37 38 39

.5736 .5878 .6018 .6157 .6293

.8192 .8090 .7986 .7880 .7771

.7002 .7265 .7536 .7813 .8098

1.7434 1.7013 1.6616 1.6243 1.5890

1.2208 1.2361 1.2521 1.2690 1.2868

1.4281 1.3764 1.3270 1.2799 1.2349

40 41 42 43 44

.6428 .6561 .6691 .6820 .6947

.7660 .7547 .7431 .7314 .7193

.8391 .8693 .9004 .9325 .9657

1.5557 1.5243 1.4945 1.4663 1.4396

1.3054 1.3250 1.3456 1.3673 1.3902

1.1918 1.1504 1.1106 1.0724 1.0355

Field Geologists’ Manual

cosec ∞

373

MATHEMATICAL TABLES AND CONVERSION FACTORS

374

Deg. 45 46 47 48 49

sin .7071 .7193 .7314 .7431 .7547

cos .7071 .6947 .6820 .6691 .6561

tan 1.0000 1.0355 1.0724 1.1106 1.1504

cosec 1.4142 1.3902 1.3673 1.3456 1.3250

sec 1.4142 1.4396 1.4663 1.4945 1.5243

cot 1.0000 0.9657 0.9325 0.9004 0.8693

50 51 52 53 54

.7660 .7771 .7880 .7986 .8090

.6428 .6293 .6157 .6018 .5878

1.1918 1.2349 1.2799 1.3270 1.3764

1.3054 1.2868 1.2690 1.2521 1.2361

1.5557 1.5890 1.6243 1.6616 1.7013

0.8391 0.8098 0.7813 0.7536 0.7265

55 56 57 58 59

.8192 .8290 .8387 .8480 .8572

.5736 .5592 .5446 .5299 .5150

1.4281 1.4826 1.5399 1.6003 1.6643

1.2208 1.2062 1.1924 1.1792 1.1666

1.7434 1.7883 1.8361 1.8871 1.9416

0.7002 0.6745 0.6494 0.6249 0.6009

60 61 62 63 64

.8660 .8746 .8829 .8910 .8988

.5000 .4848 .4695 .4540 .4384

1.7321 1.8040 1.8807 1.9626 2.0503

1.1547 1.1434 1.1326 1.1223 1.1126

2.0000 2.0627 2.1301 2.2027 2.2812

0.5774 0.5543 0.5317 0.5095 0.4877

65 66 67 68 69

.9063 .9135 .9205 .9272 .9336

.4226 .4067 .3907 .3746 .3584

2.1445 2.2460 2.3559 2.4751 2.6051

1.1034 1.0946 1.0864 1.0785 1.0711

2.3662 2.4586 2.5593 2.6695 2.7904

0.4663 0.4452 0.4245 0.4040 0.3839

70 71 72 73 74

.9397 .9455 .9511 .9563 .9613

.3420 .3256 .3090 .2924 .2756

2.7475 2.9042 3.0777 3.2709 3.4874

1.0642 1.0576 1.0515 1.0457 1.0403

2.9238 3.0716 3.2361 3.4203 3.6280

0.3640 0.3443 0.3249 0.3057 0.2867

75 76 77 78 79

.9659 .9703 .9744 .9781 .9816

.2588 .2419 .2250 .2079 .1908

3.7321 4.0108 4.3315 4.7046 5.1446

1.0353 1.0306 1.0263 1.0223 1.0187

3.8637 4.1336 4.4454 4.8097 5.2408

0.2679 0.2493 0.2309 0.2126 0.1944

80 81 82 83 84

.9848 .9877 .9903. .9925 .9945

.1736 .1564 1392 .1219 .1045

5.6713 6.3138 7.1154 8.1443 9.5144

1.0154 1.0125 1.0098 1.0075 1.0055

5.7588 6.3925 7.1853 8.2055 9.5668

0.1763 0.1584 0.1405 0.1228 0.1051

85 86 87 88 89

.9962 .9976 .9986 .9994 .9998

.0872 .0698 .0523 .0349 .0175

11.43 14.30 19.08 28.64 57.29

1.0038 1.0024 1.0014 1.0006 1.0002

11.474 14.34 19.11 28.65 57.30

0.0875 0.0699 0.0524 0.0349 0.0175

Field Geologists’ Manual

MATHEMATICAL TABLES AND CONVERSION FACTORS

12.2. THE INTERNATIONAL SYSTEM OF UNITS (S.I.) Physical quantity length

mass ( commonly called ‘weight’)

time interval

area

volume

volume (for fluids only)

velocity and speed

force energy power density

density (for fluids only) pressure pressure (for meteorology) electric current potential difference or electromotive force electrical resistance frequency

temperature plane angle

Field Geologists’ Manual

Name of unit metre millimetre centimetre kilometre international nautical mile (for navigation) kilogram gram tonne second minute hour day square metre square millimetre square centimetre hectare cubic metre cubic millimetre cubic centimetre cubic decimetre litre§ millilitre kilolitre metre per second kilometre per hour knot (for navigation) newton* joule* watt* kilogram per cubic metre tonne per cubic metre gram per cubic centimetre kilogram per litre gram per millilitre pascal bar millibar ampere † volt*, † ohm* † hertz* revolution per minute kelvin degree Celsius‡ radian milliradian

1

Value base unit 0.001 m 0.01 m 1 000 m

Symbol m mm cm km

1 852 m base unit (1 000 g) 0.001 kg 1 000 kg base unit 60 s 60 min 24 h SI unit 0.000 001 m2 0.000 1 m2 10 000 m2 SI unit 10- 9m3 0.000 001 m3 0.001 m3 0.001 m3 0.001 L 1 000 L (1 m3) SI unit L 0.27 m/s 1 n mile/h or 0.514 m/s SI unit SI unit SI unit SI unit 1 000 kg/m3 1 000 kg/m3 1 000 kg/m3 1 000 kg/m3 SI unit (N/m2) 100 000 Pa 100 Pa base unit SI unit SI unit SI unit 1 Hz 60 base unit K SI unit 0.001 rad

n mile kg g t s min h d m2 mm2 cm2 ha m3 mm3 cm3 dm3 L mL kL m/s or m s-1 km/h or km h-1 kn N J W kg/m3 or kg m- 3 t/m3 or tm- 3 g/cm3 or g cm- 3 kg/L or kgL- 1 g/mL or g mL- 1 Pa b mb A V Hz rpm or rev/min K °C rad mrad

375

MATHEMATICAL TABLES AND CONVERSION FACTORS

Physical quantity

Nmne of unit degree minute

Value π/180 rad 1o

Symbol ° ′

60 second amount of substance * † ‡ §

1.

mole

′′

1′ 60 base unit

mol

Decimal multiples commonly associated with this unit are kilo (× 1000), mega (× 1 000 000) and giga ( × 1 000 000 000). Decimal submultiples commonly associated with this unit are milli (× 0.001) and micro (× 0.000 001). The units of temperature on the Celsius scale (°C) and the thermodynamic scale (K) are equal. A temperature t on the Celsius scale is related to a temperature T on the thermodynamic scale by the relationship t = T – 273.15. For use of symbol L see Australian Standard 1000 – 1979.

From Metric Conversion Board, 1971. Metric Conversion for Australia, pp 15 and 16 (Australian Government Publishing Service: Canberra), by permission.

12.3.1. RECOMMENDED PRACTICE FOR METRIC CONVERSION 1 ft2 1 yd2 1 ac 1 square mile 1 rood 1 perch

UNITS Precision Conversion factors have in general been given to seven significant figures, a lesser number of significant figures implying an exact conversion factor. The number of figures used should relate to the required precision. Care is required when converting any imperial measurements that too much precision is not introduced or implied. Refer to MCB publication Metric Practice. eg 94 ft = 28.7 m NOT = 28.6512 m Surveying Distance All measurements between survey stations should be recorded in metres (m) to three decimal places. 1 ft = 0.304 8 m 1 yd = 0.9144 m 1 mile = 1609.344 m Measurements of rock excavations should be to the nearest 0.1 metre. Area Lease areas will be expressed in hectares (ha) or square kilometres (km2) . 10 000 m2 = 1 ha 100 ha = 1 km2 Smaller areas will be expressed in square metres (m2).

376

= 0.092 903 04 m2 = 0.836 127 4 m2 = 0.404 685 6 ha = 2.589 988 km2 = 1011.714 m2 = 25.292 85 m2

Volume Most usual unit will be cubic metres (m3) although litres (L) may be used for fluid measurement. 1 ft3 = 0.028 316 85 m3 2 1 yd = 0.764 5544 9 m3 1000 litres = 1 m3 Note: Two symbols for litre (L and 1) are legally prescribed in regulations under the Commonwealth Weights and Measures (National Standards) Act. However, the Metric Conversion Board recommends L as the preferred symbol. It is the only officially recommended symbol in USA and is preferred in Canada. It is also being used increasingly in other countries (from AS 1000-1979). Angles No change is involved. Angles will continue to be recorded in degrees, minutes and seconds.

Levelling Four and five metre staffs are available graduated at metre (m) and 10 millimetre (mm) intervals.

Field Geologists’ Manual

MATHEMATICAL TABLES AND CONVERSION FACTORS

Note: Estimate millimetres Graduated facings can be obtained.

Mine datum At all new mining developments the reduced level should be started in terms of a datum which is 10 000 metres (m) below the Australian Height Datum determined by National Mapping. Contours—select from range 0.5 m, 1.0 m, 2.0 m, 5.0 m depending on degree of detail.

Density Density is expressed as tonnes per cubic metre (t/m3) or kilograms per cubic metre (kg/m3). Note: The term specific gravity should be phased out (Refer AS 1376 – 1973)

Note 4: The General Conference on Weights and Measures has deprecated the use of the metric carat. However its use still prevails in international gem trade. It is hoped that the trade will ultimately adopt the gram in place of the metric carat. 1 CM = 0.2g. 1 carat (1877) = 1.028 CM At this stage, in New South Wales, Victoria, Queensland, and Tasmania, diamonds and other precious stones may only be sold by reference to the metric carat.

Alluvial deposits Alluvial deposits at present expressed in terms of pounds, ounces, pennyweights or grams per cubic yard will be expressed as grams per cubic metre (g/m3 ).

Mine plans

Ore grades

For mine planing, recommended scales are specified in Australian Standard AS 1100.7. Co-ordinate grid lines 100 or 200 millimetres (mm) apart are recommended. Grid lines at these spacing suit the recommended scales by giving suitably rounded numbers for major co-ordinate lines and are not so far apart that major scale errors are introduced due to paper shrinkage.

Grades of some ore eg tungstic oxide, antimony ore, manganese ore, beryllium ore, have been expressed as a percentage of a ton (a ton of material at one per cent). These will be expressed as a percentage of a tonne (t). All other grades will continue to be expressed as percentages.

Sampling

Express as megajoules per kilogram (MJ/kg).

Precious metal grades (gold, silver)

Relevant conversion factors

Express in grams per tonne (g/t). Note 1: This is numerically equal to parts per million. It is recommended that grades be converted now in grams per tonne, with a conversion of mass back to ounces troy being made prior to sale. If grades are converted to ounces per tonne, a later conversion would undoubtedly be necessary to grams per tonne. The consequent confusion of two conversions is to be avoided. Note 2: Until London Bullion Market changes to SI units, gold and silver bullion will be marketed in ounce troy.

Uranium grade Express in kilograms per tonne (kg/t). Note 3: This is numerically equal to parts per 1000.

Specific energy for coal

Mass (precious metals) 1 dwt = 1.555 174 g 1 oz tr = 31.103 48 g Mass (ore, etc) 1 ton = 1.016 047 t 1 sh tn = 0.907 184 7 t Grade 1 dwt/sh tn = 1.714 286 g/t 1 dwt/ton = 1.530 612 g/t 1 oz tr/ton = 30.612 24 g/t 1 oz tr/sh tn = 34.285 71 g/t 1 lb/ton = 0.446 428 6 kg/t 1 lb/yd3 = 593.276 3 g/m3 1 oz (avoirdupois)/yd3 = 37.079 78 g/m3 1 dwt/yd3 = 2.034 906 g/m3 3 1 gr/yd = 0.084 753 78 g/m3 Specific energy 1 Btu/lb = 0.002 326 MJ/kg

Grade of diamonds and other gem deposits Express as metric carats per cubic metre (CM/m3 ).

Field Geologists’ Manual

377

MATHEMATICAL TABLES AND CONVERSION FACTORS

Mine ventilation

Velocity of air Use metres per second (m/s). 1 ft/min = 0.005 08 m/s Useful rule of thumb: 200 ft/min = 1 m/s

Notes I. Gauge and absolute pressure The distinction between gauge and absolute pressure should be made clear by following the convention that unless otherwise stated pressures refer to gauge pressures: if an absolute pressure is intended it must be specified eg an absolute pressure of 4.2 kPa.

Flow of air

2. Conversion of columns of liquids

Use cubic metres per second (m3/s). 1 ft3/min = 0.000 471 947 4 m3/s

All factors relating columns of liquids to pascals are dependent on fluid density, the local value of ‘g’ and temperature. Factors given are for the conditions as nominated in Australian Standard 1376-1973.

Note: Useful rule of thumb for conversion: 2000 ft3/min = 1 m3/s

Density

Differential pressure

Use kilograms per cubic metre (kg/m3), tonnes per cubic metre (t/m3). 1 lb/ft3 = 16.018 46 kg/m3

Fluids in glass manometers are commonly used to measure pressure differences. Results should be expressed in pascals. Where p = h × ρ × gn p = differential pressure (Pa) h = manometer reading (m) ρ = fluid density (kg/m3) gn = acceleration due to gravity = 9.806 65 m/s2

Note: Correct for temperature and pressure Density air (dry) =  pressure (kPa) 293.15  3 1.205 ×  kg/m 101.325  temp (K) Density air (dry) at 20°C and 101.325 kPa = 1.205 kg/m3. Density moist air (50 per cent r.h.) at 20°C and 101.325 kPa = 1.184 kg/m3.

Temperature Use degrees Celsius (°C). Record to one decimal point. For thermodynamic calculations use kelvin (K). K = °C + 273.15.

Pressure units Use pascals (Pa), kilopascals (kPa) or megapascals (MPa). Reference will be found to the millibar in UK practice. The pascal is the SI unit of pressure and its use in Australia is recommended. The millibar (mb) is retained for meteorological use only. 1 inH2O at 20°C and 9.806 65 m/s2 = 0.248 641 6 kPa 1 inHg at 0°C and 9.806 65 m/s2 = 3.386 384 kPa 1 mmHg at 0°C and 9.806 65 m/s2 = 0.133 322 2 kPa 1 mmH2O at 20°C and 9.806 65 m/s2 = 9.789 039 Pa 1 lbf/in2 = 6.894 757 kPa

378

Velocity pressure Use pascals (Pa) Where Pv = ½ Cv2ρ Pv = measured velocity pressure (Pa) C = dimensionless coefficient for the pitot-static tube (normally close to unity) v = air velocity (m/s) p = air density (kg/m3) Airway resistance (Formula and ‘K’ factors) Based on Chezy Darcy and Atkinson’s relationships. Expressed in pascals (Pa) fρ CLQ2  fρ Sv2  =  2 A3  2 A  KCLQ2 = A3

P =

= PQ2 fρ 2 KCL  P  ‘R’ = 3  = 2  A  Q  ‘K’ =

where P f

= frictional pressure loss (Pa) = dimensionless coefficient

Field Geologists’ Manual

MATHEMATICAL TABLES AND CONVERSION FACTORS

ρ = air density (kg/m3) C = airway circumference (m) L = length of airway (m) A = cross-section area of airway (m2) S = rubbing surface area C × L (m2) V = airflow velocity (m/s) Q = airflow quantity (m3/s) ‘K’ = friction factor (kg/m3) ‘R’ = resistance (kg/m3)

Mass flow Expressed as kilograms per second (kg/s), grams per second (g/s). 1 lb/s = 0.453 592 4 kg/s 1 lb/min = 7.559 873 g/s

Velocity Express as metres per second (m/s) 1 ft/min = 0.005 08 m/s

Note (1) The ‘K’– and ‘R’–factors include a density term. For general understanding and communication their values will be quoted for air at standard density (‘KS’). For other conditions the correct values can be obtained thus— ρ 1.205 ρ ‘R’ = ‘RS’ × 1.205

‘K’ = ‘KS’ ×

Both South Africa and Great Britain are using ‘K’ and ‘R’ as above. The metric unit for ‘K’ is kg/m3. The imperial unit for ‘K’ is lbf.min2/ft4. ‘K’ metric = 1.855 364 × ‘K’ imperial at standard gravity. Note (2) ‘K’ imperial relates to volume flow in thousands of cubic feet per minute. ‘K’ metric relates to volume flow in cubic metres per second.

Refrigeration

Pressure Express as kilopascals (kPa) . Useful rules of thumb: 100 lbf/in2 = 700 kPa 1 inH2O = 0.25 kPa 1 inHg = 3.5 kPa For marking of pressure gauges refer to Australian Standard 1349—1973.

Rockdrill penetration speed Expressed in millimetres per minute (mm/min) to nearest ten millimetres. For high penetration rates in very soft rock express as metres per minute (m/min) to nearest 0.1 metre. Useful rule of thumb: 1 ft/ min = 300 mm/min.

Pipe diameter and wall thickness Express in millimetres (mm). Note: Rounded nominal dimensions are used to describe pipe; ie six inch diameter becomes 150 mm pipe.

Use watts (W) or multiples 1 ton (refrigeration) = 12 000 Btu/h = 3.516 853 kW

Pressure loss (frictional)

Compressed Air

Express as kilopascals per kilometre (kPa/km), pascals per metre (Pa/m).

Relevant conversion factors

Volume flow—compressor capacity 3

Express as cubic metres per second (m /s), litres per second (L/s). Useful rules of thumb: 2000 ft3/min = 1 m3/s 2 ft3/min = 1 L/s ie A 30 000 ft3/min compressor will be known as a 15 m3/s compressor. A 100 ft3/min compressor will be known as a 50 L/s compressor.

Field Geologists’ Manual

Volume flow 1 ft3/min = 0.000 471 947 4 m3/s = 0.471 947 4 L/s Mass flow 1 lb/min = 7.559 873 g/s 1 lb/s 0.453 592 4 kg/s Velocity 1 ft/min = 0.005 08 m/s Pressure 1 lbf/in2 = 6.894 757 kPa

379

MATHEMATICAL TABLES AND CONVERSION FACTORS

1 inH2O

= 248.641 6 Pa at 20°C and 9.806 65 m/s2 1 inHg = 3.386 384 kPa at 0°C and 9.806 65 m/s2 Rockdrill penetration rate 1 ft/min = 304.8 mm/min Pressure loss 1 lbf/in2 .1000 ft = 22.620 59 Pa/m

Note: Express in metres (m) in calculations.

Diameter of solid particles Describe in millimetres (mm), micrometres (µm) Note 1: Express in metres (m) in calculations. Note 2: The term ‘micron’ should no longer be used as a synonym for ‘micrometre’.

Water supply and pumping

Force or resistance

Quantity of water

Express as newtons (N). 1 lbf = 4.448 222 N at standard gravity.

Express in terms of litres (L), kilolitres (kL), megalitres (ML) or cubic metres. 1 ac. ft = 1 233.482 m3 or 1.233 482 ML

Volume flow (i)

Pumping rates previously expressed as gallons per minute to be expressed as litres per second (L/s). Useful rule of thumb: 100 gal/min= 7.5 L/s

(ii) Daily water supply to towns or plants previously expressed in gallons to be expressed in megalitres. Useful rule of thumb: 1 × 106 gal = 4.5 ML

Pressure, head of liquid or slurry Express as pascals (Pa), kilopascals (kPa) . 1 mm H2O (20°C and 9.806 65 m/s2) = 9.789 039 Pa.

Hydraulic gradient Express as kilopascals per metre (kPa/m) of pipe.

Flow rate Describe in litres per second (L/s) but use cubic metres per second (m3/s) in calculations.

Velocity of flow or settling velocity Express in metres per second (m/s).

Head While the SI unit of pressure is the pascal, it may be necessary in certain circumstances to talk in terms of head of liquid. Useful rule of thumb: 1 mH2O = 10 kPa

Density Express as tonnes per cubic metre (t/m3) or kilograms per litre (kg/L). Note 1: The term ‘specific gravity’ should be phased out (Refer AS 1376—1973). Note 2: 1 t/m3 = 1 kg/L

Pump power Express in/kilowatts (kW)

Viscosity

Relevant conversion factors

(i)

Quantity of water 1 gal = 4.546 09 litres 1 US gal = 3.785 412 litres Flow 1 gal/min = 0.075 768 17 L/s Power 1 hp = 0.745 699 9 kW Pumping solids (pulp flow)

Diameter of pipe Describe in millimetres (mm)

380

Dynamic viscosity. Express as pascal second (Pa.s), millipascal second (mPa.s). Note: It is expected that the poise (P) will be used by certain industries for some time, although this practice should be phased out as soon as possible. 1P = 0.1 Pa.s 1 cP = 1 mPa.s

(ii) Kinematic viscosity. Express as square metres per second (m2/s) or square millimetres per second (mm2/s). Note: It is expected that the usages of stokes (St) could continue for some time in certain circumstances although this should also be phased out as soon as possible.

Field Geologists’ Manual

MATHEMATICAL TABLES AND CONVERSION FACTORS

= 100 mm2/s = 1 mm2/s

1 St 1 cSt

Tear strength Express as newtons (N).

Power

Impact

Express as kilowatts (kW), megawatts (MW) and gigawatts (GW).

Express as joules (J).

Length Metallurgical

Express as metres (m).

Concentration

Thickness

Reagent consumption is to be expressed in kilograms per tonne or grams per tonne (kg/t, g/t).

Express as millimetres (mm).

Smelting

Express as millimetres (mm).

(i)

Belt speed

Metal loss in slag is to be expressed as kilograms per tonne (kg/t).

(ii) Hearth areas are to be expressed in square metres (m2). (iii) Furnace thermal efficiency, previously expressed as millions of British thermal units per long ton of solid charge will now be expressed as gigajoules per tonne (GJ/t). 1 × 10 Btu/ton = 1.038 392 GJ/t 6

Refining Tankhouse-current density will be expressed as amperes per square metre (A/m2).

Particle size (i)

Express as millimetres (mm) or micrometres (µm). Note: The term ‘micron’ should no longer be used as a synonym for ‘micrometre’.

(ii) Mesh sizes. Screens will be designated in aperture sizes in millimetres (mm) and micrometres (µm). Refer to Australian Standard 1152.

Width

Express as metres per second (m/s). Rock mechanics

Stresses Express as megapascals (MPa). 1 lbf/in2 = 0.006 894 757 MPa Useful rules of thumb: 1 000 lbf/in2 = 7 MPa 30 000 lbf/in2 = 210 MPa 45 000 lbf/in2 = 315 MPa

Young’s Modulus Express as megapascals (MPa)

Compressive strength Express as megapascals (MPa)

Tensile strength Express as megapascals (MPa) Fuel

Conveyor belts

Specific energy Tensile strength

Express in megajoules per kilogram (MJ/kg).

Express as kilopascals (kPa), megapascals (MPa).

Belt tension Express as newtons (N).

Ply adhesion Express as kilonewtons per metre (kN/m).

Heating value (i)

Gaseous Fuel. Express in megajoules per cubic metre (MJ/m3) at stated pressure, temperature and humidity.

(ii) Liquid Fuel. Express in megajoules per litre (MJ/L).

Cover tensile strength Express as kilopascals (kPa).

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381

MATHEMATICAL TABLES AND CONVERSION FACTORS

Relevant conversion factors 1 Btu/lb 1 Btu/ft3

To convert x mile/gal to y litre/100 km

= 0.002 326 MJ/kg = 0.037 258 95 MJ/m3

Note: It is assumed the volumes involved are measured under the same conditions of temperature, pressure and humidity.

y =

282.480 94 x

Timber

Express Winding Ropes

Width in millimetres (mm). Thickness in millimetres (mm). Length in metres (m), standard lengths are in rises of 0.3 m starting at 1.8 m. Volume in cubic metres (m3) 100 super feet = 0.235 973 7 m3

Rope circumference Should not be used. Express as millimetres diameter (mm).

Rope diameter

REPORTING RESULTS

Express as millimetres (mm).

Rope mass Express as kilograms per 100 metres (kg/100 m). Refer to AS 1426-1973 steel wire ropes for winding and haulage purposes in mines.

It is desirable that a uniform approach be adopted by the mining and metallurgy industry for the reporting of results to statutory authorities and to the press. Mass of ore, mullock and concentrates

tonnes (t)

Tensile strength

Development advance

metres (m)

Express as megapascals (MPa) .

Volumes of rock

cubic metres (m3)

Note: that UK catalogues are still quoting as kgf/mm2. 1 kgf/mm2 = 9.806 65 MPa

Breaking load Express as kilonewtons (kN) .

Mass of products—such as: blister copper, crude lead, coal or ilmenite, etc precious metals (gold and silver)

tonnes (t)

diamonds

metric carats (CM) grams (g)

oil

tonnes (t)

Explosives breaking rate Express explosives breaking rate as tonnes per kilogram (t/kg) and powder factor as kilograms per tonne (kg/t). Transport (haulage)

grams (g) kilograms (kg)

Volumes of: natural gas

cubic metres (m3)

oil

cubic metres (m3)

Express Velocity as kilometres per hour (km/h). Mass × distance as tonne kilometre (t.km). Fuel consumption as litres per 100 kilometres (L/100 km) Mass per distance as tonne per kilometre (t/km).

Relevant conversion factors 1 mile/h = 1.609 344 km/h 1 ton.mile = 1.635 169 t.km 1 ton/mile = 0.631 342 3 t/km

382

The following convention is in accordance with the 9th CGPM meeting and also in accordance with the current Commonwealth Style Manual of the Australian Government. Terms

Significance

Corresponding Decimal Factor

million

thousand × thousand

106

billion

million × million

1012

trillion

million × billion

1018

quadrillion

million × trillion

1024

Field Geologists’ Manual

MATHEMATICAL TABLES AND CONVERSION FACTORS

A different convention is in use in the United States of America and now also in France where: ‘billion’ signifies a thousand times a million (109) ‘trillion’ signifies a million times a million (1012) ‘quadrillion’ signifies a million times a US billion (1015) In view of the existence of the different conventions, use of the terms billion, trillion and quadrillion should be avoided.

UNITS, PREFIXFS AND THEIR SYMBOLS UNITS AND PREFIXFS WITHIN SI Name ampere atto (prefix 10-18) candela centi (prefix 10-2)* coulomb deci (prefix 10-1)* deka (prefix 101)* farad femto (prefix 10-15) giga (prefix 109) gram hecto (prefix 102)* henry hertz joule kelvin kilo (prefix 103) kilogram lumen lux mega (prefix 106) metre micro (prefix 10-6) milli (prefix 10-3) mole nano (prefix 10-9) newton ohm pascal pico (prefix 10-12) radian

Symbol A a cd c C d da F f G g h H Hz J K k kg lm lx M m µ m mol n N Ω Pa p rad

second siemens steradian tera (prefix 1012) tesla volt watt weber * not generally used in technical applications.

s S st T T V W Wb

OTHER UNITS WHICH MAY BE ENCOUNTERED IN THE INDUSTRY Name ampere hour centipoise centistokes day degree (angle) degree Celsius hectare hour kilogram per litre kilometre per hour kilowatt hour knot litre ‡ metric carat millibar minute ( angle ) minute (time) nautical mile (international) revolution per minute revolution per second second (angle) tonne § tonne per cubic metre watt hour

Symbol A.h cP (†) cSt (†) d ° °C ha h kg/L km/h kW.h kn L(*) CM(†) mb ′ min n mile r/min r/s ′′ t t/m3 W.h

*

See note re ‘litre’.

†

Continued use in Australia deprecated.

‡

Used in conjunction with all prefixes – eg millilitre, microlitre, etc.

§

Used in conjunction with positive power prefixes – eg megatonne.

From Metric Conversion Board; Engineering Industry Advisory Committee, 1974. Metric Conversion Information Brochure, Mining and Metallurgy Industry, pp 9-14 (Australian Government Publishing Service: Canberra), by permission, amended to agree with AS 1000-1979.

Field Geologists’ Manual

383

MATHEMATICAL TABLES AND CONVERSION FACTORS

12.3.2. CONVERSION FACTORS, IMPERIAL AND INTERNATIONAL SYSTEMS One acre

(Multiplier for Col. 1) = 160 square perches = 4 roods = 43 560 sq. ft = 4840 square yards = 0.404 685 6 ha = 4046.856 m2 acre foot = 1233.482 m3 = 43 560 cu. ft = 271 327 Imp. gallons Admiralty nautical mile = 1.853 184 km atmosphere = 1013.25 millibars (20°C) = 101.325 x 103 Pa (20°C) = 760 mm head of mercury (20°C) = 10.3509 metres head of water (20°C) = 14.6960 pounds force/square inch (20°C) average month = 30.42 days = 730 hours = 4.34 weeks barrel, US = 0.158 987 m3 = 0.125 to 0.150 t crude oil = 158.987 3 L = 34.97 Imp. gallons = 42 US gallons British thermal unit (Btu) = 1055.06 J Btu/cubic foot = 37.258 95 kJ/m3 Btu/gallon = 0.232 kJ/L Btu/hour = 0.2931 W Btu/pound = 2.326 J/g* = 0.002 326 MJ/kg bushel = 1.284 352 cubic feet = 0.0364 m3 bushel, US = 0.0352 m3 = 0.968 940 bushel calorie, international = 4.1868 J* calorie, 15° (water calorie) = 4.1855 J* calorie, thermochemical = 4.184 J* carat, metric (CM) = 0.2 g = 3.0865 grains cental = 100 pounds cent/cubic yard = 0.764 555 cents/m3 cent/long ton = 1.016 047 cents/t cent/short ton = 0.907 185 cents/t chain = 100 links = 66 feet = 22 yards = 20.116 8 m* * Exact Australian Standard conversion factor.

384

One Cheval vapeur (C.V.) circle cubic centimetre cubic metre

(Multiplier for Col. 1) = 735.5 W = 6.2832 radians = 0.061 024 cubic inches = 103 L = 61023.7 cubic inches = 35.314 7 cubic feet = 1.307 95 cubic yards = 27.4962 bushels = 219.969 248 Imp. gallons cubic foot = 1728 cubic inches = 0.028 317 m3 = 6.228 84 gallons = 28.316 85 L cubic foot/second = 28.3168 L/s cubic foot/long ton = 27.87 × 10-6m3/kg cubic foot/pound = 64.43 m3/kg cubic foot/minute = 471.947 4 × 10-6m3/s cubic inch = 16 387.064 mm3* = 276.837 minims cubic yard = 27 cubic feet = 0.764 554 857 m3 = 168.178 Imp. gallons cycle/second = 1 Hz degree (angle) = 17.453 293 × 10-3 rad degree Celsius = 0.555 (°F − 32) degree Fahrenheit = 1.8 (°C) + 32 degree Kelvin (TK) = C + 273.15 drachm = 3 scruples = 60 grains = 3.887 934 6 g drachm, fluid = 60 minims = 3.551 633 mL = 0.216 734 cubic inches dram = 27.343 75 grains = 1.771 845 g fathom = 6 feet = 1.8288 m* fluid ounce = 8 fluid drachms = 28.413 062 mL = 1.731 375 cubic inches foot = 12 inches = 0.3048 m* foot head of water = 2983.6992 Pa (at 20°C) foot/minute = 5.08 × 10-3 m/s* foot poundal = 0.042 14 J foot pound force = 1.335 818 J

Field Geologists’ Manual

MATHEMATICAL TABLES AND CONVERSION FACTORS

One (Multiplier for Col. 1) foot pound force/minute= 80.149 W foot pound force/second= 1.335 818 W foot/second = 0.3048 m/s* foot, superficial = 2.359 737 × 10-3 m3 furlong = 10 chains = 201.168 m* gallon = 160 fluid ounces = 8 pints = 4 quarts = 4.546 09 L* = 1.200 95 US gallons = 277.42 cubic inches = 0.160 544 cubic feet = 4.546 09 × 10-3 m3* gallon (US) = 3.785 412 L = 0.832 675 Imp. gallons = 231 cubic inches* = 0.133 681 cubic feet gallon/hour = 1.262 803 × 10-3L/s gallon/minute = 0.075 768 17 L/s giga (G) = 109 gill = 142.065 mL = ¼ pint grain = 0.041 667 pennyweight = 1.428 57 × 10-4 pounds = 0.064 798 918 g* grain/cubic yard = 0.084 753 78 g/m3 grain/gallon (Clark Hardness) = 14.3 ppm CaCO3 by weight grain/US gallon (Clark Hardness) = 17.1 ppm CaCO3 by weight grain/normal cubic foot = 2.2883 × 106 µg/m3 (suspended solids) gram = 15.432 358 grains = 5 Metric carats (CM) = 35.273 962 × 10-3 ounces = 2.204 623 × 10-3 pounds gram/cubic centimetre = 1 g/mL = 1 kg/L = 1 t/m3 = 62.427 961 lbs/ft3 = Density gram/cubic metre = 11.7993 grains/cubic yard = 0.491 64 dwt/cubic yard = 1.686 × 10-3 lbs/cubic yard gram/tonne = 1 part per million (ppm) = 0.0001 per cent = 0.583 33 dwt (Troy)/short ton * Exact Australian Standard conversion factor.

Field Geologists’ Manual

One

(Multiplier for Col. 1) = 0.653 33 dwt (Troy)/long ton = 0.029 17 oz (Troy)/short ton = 0.032 666 oz (Troy)/long ton = 0.002 24 lbs (avoir)/long ton gravity, standard = 9.806 65 m/s2* = 32.174 05 ft/s2 hand = 0.1016 m = 4 inches hectare = 10 000 m2 = 11959.9 square yards = 2.471 053 8 acres horsepower = 745.699 87 W = 550 foot pounds force/second horsepower hour = 2.684 519 MJ hundredweight = 112 pounds = 50.802 345 kg inch = 25.4 mm* inch head of water = 248.6416 Pa at 20°C joule = 0.737 562 foot pound force kilo (k) = 103 kilogram (kg) = 2.204 622 6 pounds = 32.150 745 oz Troy kilogram force = 9.806 65 N kilogram force/square centimetre = 98.0665 kPa kilogram force/square metre = 9.806 65 Pa kilogram force metres per second per second = 1 N kilogram/cubic metre = 0.062 428 lbs/cubic foot kilogram/litre = Density kilogram/metre = 0.671 97 lb/ft kilolitre = 219.969 gallons kilometre = 0.621 371 miles kilometre/litre = 2.824 8 m.p.g. kilonewton = 224.809 pounds force kilopascal = 0.145 lbs/sq. inch kilowatt = 737.562 foot lbs force/second = 1.34102 horsepower kilowatt hour = 3.6 MJ = 3412.14 British thermal units knot, international = 1.852 km/hour link = 7.92 inches = 0.66 feet = 0.201 168 m litre = 0.219 969 gallons = 0.264 17 US galls. = 1.759 75 pints = 50.812 839 cu. ins. = 35.195 fluid ounces = 0.001 m3 282.481 m.p.g. litre per 100 km = litres /100 km litre/second = 13.2 gallons/minute

385

MATHEMATICAL TABLES AND CONVERSION FACTORS

One (Multiplier for Col. 1) long ton (see ton, long) mega (M) = 106 metre = 3.280 84 feet = 1.093 613 2 yards metre/second = 196.850 39 feet/minute metric carat = 0.2 grams metric horsepower = 735.5 W micro (µ) = 10-6 mile = 5280 feet = 1760 yards = 80 chains = 8 furlongs = 1.609 344 km* mile/gallon = 0.354 km/L 282.481 L/100 km m.p.g. mile/hour = 0.447 04 m/s milli (m) = 10-3 millibar = 100 Pa millilitre = 0.035 195 fluid ounces = 0.281 561 fluid drachms = 16.893 6 minims millilitre/second = 0.792 gallons/hour millimetre = 0.039 4 inches millimetre/second = 0.196 85 ft/minute minute (angle) = 0.290 89 × 10-3 radians minim = 0.059 194 mL = 3.612 24 × 10-3 cubic inches nano (n) = 10-9 nautical mile, Admiralty = 1.853 184 km nautical mile, international = 1.852 km newton = 0.224 8 lbs force ounce (Apothecaries) = 8 drachms = 1 ounce (Troy) ounce (Avoirdupois) = 437.5 grains = 16 drams = 28.349 523 g ounce (fluid) see fluid ounce ounce/cubic yard = 37.07978 g/m3 ounce (Troy) = 20 pennyweights = 480 grains = 31.103 477 g ounce (T)/long ton = 30.612 24 g/t ounce (T)/short ton = 34.285 71 g/t part per million (ppm)—see gram/tonne pascal = 0.020 885 lbs force/sq. ft =

* Exact Australian Standard conversion factor.

386

One (Multiplier for Col. 1) peck = 9.092 18 × 10-3 m3 = 2 gallons pennyweight (Troy) = 24 grains = 1.555 173 8 g pennyweight (T) / cu. yd. = 2.034 906 g/m3 pennyweight (T) / l. ton = 1.530 612 g/t pennyweight (T) / sh. ton = 1.714 286 g/t perch (area) = 25.292 85 m2 perch (length) = 5.0292 m* pico (p) = 10-12 pferdestarke (PS) = 735.5 W pi (π) = 3.141 592 654 pint = 20 fluid ounces = 0.568 261 L = 34.667 4 cubic inches point (rainfall) = 0.254 mm* pole = 5.0292 m* pound (Avoir) = 7000 grains = 16 ounces = 453.592 37 g* pound (Troy) = 12 ounces (Troy) = 5760 grains pound force/square inch = 6.894 757 kPa pound/cubic foot (Density) = 16.018 46 kg/m3 = 0.016 018 t/m3 pound/cubic inch (Density) = 27.68 t/m3 pound/cubic yard (Assay) = 593.2763 g/m3 pound/long ton (Assay) = 0.446 428 6 kg/t pound/minute = 7.559 873 g/s pound force = 4.448 N pound force/square foot = 47.880 259 Pa pound/short ton (Assay)= 398.597 g/t quart = 40 fluid ounces = 2 pints = 1.136 522 L quarter (mass) = 12.700 586 kg quintal = 100 kg radian = 57.295 78° rod = 5.0292 m* rood = 1210 square yards = 1011.714 m2 scruple = 20 grains = 1.296 g short ton see ton, short square (of flooring) = 100 sq.ft = 9.29 m2 square centimetre = 0.155 000 square inches square foot = 144 square inches = 0.092 903 04 m2 square inch = 645.16 mm2

Field Geologists’ Manual

MATHEMATICAL TABLES AND CONVERSION FACTORS

One square kilometre square metre

(Multiplier for Col. 1) = 0.386 102 square miles = 10.763 91 square feet = 1550.003 square inches square mile = 640 acres = 2.589 988 km2 square millimetre = 1.55 × 10-8 square inch square yard = 9 square feet = 0.836 127 4 m2* = 0.836 127 4 × 10-4 ha stone = 6.350 293 2 kg super foot — see foot, superficial tera (T) = 1012 tex (mass/unit length of textiles) = 1 g/km therm = 105.506 MJ* thermie = 106 water calories = 4.1855 MJ* ton, assay = 32.6667 g (in which 1 mg = 1 ounce (T) per long ton

* Exact Australian Standard conversion factor.

One ton, long

(Multiplier for Col. 1) = 2240 pounds = 20 hundredweights = 1.016 047 t ton, short (US) = 2000 pounds = 0.907 185 t ton, refrigeration = 3.516 853 kW ton (long)/vertical foot = 3.3335 t/m tonne (t) = 0.984 2 long tons = 1.102 3 short tons = 106 g = 2204.62 lbs = 1000 kg tonne/square mile/month = 13.1 mg/m2/d tonne/cubic metre = 62.4238 lbs/cubic foot tonne/vertical metre = 0.3 long tons/vertical foot US survey foot = 1.000 002 0 feet = 1200 ÷ 3937 m velocity of sound (0°C) = 332 m/s water Btu = 1 Btu (60°F) = 1054.54 J watt = 0.737 56 foot lbs force/ second yard = 3 feet = 0.9144 m*

From Australian Standard 1376, Conversion Factors, with permission from the Standards Association of Australia.

Field Geologists’ Manual

387

MATHEMATICAL TABLES AND CONVERSION FACTORS

12.3.3. CONVERSION FACTORS FOR FOREIGN, RARE AND OBSOLETE WEIGHTS AND MEASURES 2

are (metric)

= 100 m

arpent (ancient French)

= (1) area of about 0.85 acre = 0.34 ha (2) length of 192 to 192.5 ft. = 58.5 to 58.7 m

bushel (English)

= 2.1165 acres = 0.86 ha morgen (Sth. Africa) nail (obs. English) = 2 ¼ inches = 2 gallons = 9.1 L peck (obs. English)

= 8 gallons = 36.4 L = 4 pecks = 1/600th of a degree of latitude, often taken as 608 ft = 185.37 m

perch (obs. masonry meas.)

cape foot (Sth. Africa)

= 1.033 Imperial ft. = 0.3149 m

pipe (obs. English) prospecting dish

cape rood (Sth. Africa)

= 12 cape feet = 12.4 Imperial ft. = 3.7879 m

chaldron (dry measure, Eng.) cord (of wood, obs. Eng.) cubit (ancient Egypt) cup, breakfast

= 36 bushels

cable (nautical)

= 128 cu. ft. = 3.6 m3 = 18 to 22 inches = 0.457 to 0.559 m (21.8 inches in the Bible) = ½ pint = 284.13 mL

cup, metric cup, tea ell (obs. English) firkin (obs. English) flask of mercury gross (obs.) hogshead (obs. English)

= 250 mL = ¼ pint = 142.06 mL = 45 inches = 1.143 m = wine volume, 8 to 9 gall. = 36.4 to 40.9 L = 34.5 kg = 144 = wine volume, 52 ½ gall. = 238.7 L

hand (English)

= 4 inches (height of horses) = 0.1016 m = (land) subdivision of a county or shire, of area tens to hundreds of 2 km

hundred (Sth. Aust, NT) kati (Malaysia) kilderkin (obs. English)

= 1 13 lb = 0.60 kg = wine volume, 16 to 18 gallons (72.7-81.8 L)

load (obs. English) league (obs. English) miner's inch (USA)

= 1 cu. yd of alluvium

picul (Malaysia)

puncheon (obs. English) quintal (metric) quintal (obs. USA) sea mile (nautical) score Scruple (Apothecaries) shekel (ancient Palestine) shipping ton span (obs. Eng.) tablespoon tael talent (ancient Palestine) teaspoon tola vara (obs. Spanish)

verst (Russian)

military pace

388

= a length of dimension stone of 12 inch by 12 inch section; 16 ½ ft long = 100 katis = 133 13 lbs = 60.48 kg = wine volume, 105 gall. = 477.34 L = volume of the large sized dish (about 16 inches or 38 cm dia.) is usually taken as 2 gallons (or 9 L), with 112 level dishes accepted as equivalent to 1 cu. yd (146 dishes/m3) = wine volume, 70 gall. = 318.2 L = 100 kg = 100 lb = 45.36 kg = 1/60th degree of latitude = 20 = 20 grains = 252 grains = 16.33 g = 40 cu. ft = 6 inches = 0.1524 m = 1 fl. oz. = 28.413 mL = Chinese weight, 1.23 Troy oz = 3000 shekels = 1 3 fl. oz. = 9.47 mL = Indian weight, 0.375 Troy oz = 2.6816 ft = 0.8359 m; South American usage ranges from 0.8 to 1.1 m. = 3500 ft = 1067.07 m

= 3 miles = 4.83 km = rate of discharge of water, varying from 0.02 cu. ft/sec. to 0.026 cu. ft/ sec. = 0.57 to 0.74 L/sec. = 2.5 feet

Field Geologists’ Manual

Field Geologists’ Manual

′′ 5 ′′ 16 .265′′ 5 ′′ 16 No. 31 2

4 5 6

7 8 10 12 14

16 18 20

4.75 mm 4.00 mm 3.35 mm

2.80 mm 2.36 mm 2.00 mm 1.70 mm 1.40 mm

1.18 mm 1.00 mm 850 µm

8

9.5 mm 8.0 mm 6.7 mm 6.3 mm 5.6 mm

3

5 ′′ 8 .530′′ 1 ′′ 2 7 ′′ 16

Alternate 11 4′′ 1.06′′ 1′′ 7 ′′ 8 3 ′′ 4

16.0 mm 13.2 mm 12.5 mm 11.2 mm

*Standard 31.5 mm 26.5 mm 25.0 mm 22.4 mm 19.0 mm

USA1

14 16 20

7 8 9 10 12

4 5 6

3 12

.371′′ 2 12 3

.441′′

.624′′ .525′′

.883′′ .742′′

1.05′′

Mesh Designation

TYLER2

1.18 mm 1.00 mm 850 µm

2.80 mm 2.36 mm 2.00 mm 1.70 mm 1.40 mm

4.75 mm 4.00 mm 3.35 mm

9.5 mm 8.0 mm 6.7 mm 6.3 mm 5.6mm

16.0 mm 13.2 mm 12.5 mm 11.2 mm

Standard 31.5 mm 26.5 mm 25.0 mm 22.4 mm 19.0 mm

16 18 20

7 8 10 12 14

4 5 6

8

′′ 5 ′′ 16 .265′′ 1 ′′ 4 No. 3 1 2 3

5 ′′ 8 .530′′ 1 ′′ 2 7 ′′ 16

Alternate 11 4′′ 1.06′′ 1′′ 7 ′′ 8 3 ′′ 4

CANADIAN3

1.20 mm 1.00 mm 850 µm

2.80 mm 2.40 mm 2.00 mm 1.68 mm 1.40 mm

4.00 mm 3.35 mm

Nominal aperture

14 16 18

6 7 8 10 12

4 5

Nominal Mesh No.

BRITISH4

31

32

1.250 1.000

35 34 33

36

3.150 2.500 2.000 1.600

37

38

No.

4.000

5.000

Opening (mm)

FRENCH5

12.4. COMPARISON TABLE OF USA, TYLER, CANADIAN, BRITISH, FRENCH, AND GERMAN STANDARD SIEVE SERIES

1.0 mm

1.25 mm

2.5 mm 2.0 mm 1.6 mm

3.15 mm

4.0 mm

5.0 mm

6.3 mm

8.0 mm

10.0 mm

12.5 mm

20.0 mm 18.0 mm 16.0 mm

25.0 mm

Opening

GERMAN6

MATHEMATICAL TABLES AND CONVERSION FACTORS

389

390

30 35 40

45

50 60 70

80

100 120 140

170

200

230

270

325

600 µm 500 µm 425 µm

355 µm

300 µm 250 µm 212 µm

180 µm

150 µm 125 µm 106 µm

90 µm

75 µm

63 µm

53 µm

45 µm

325

270

250

200

170

100 115 150

80

48 60 65

42

28 32 35

24

TYLER2 Mesh Designation

38 µm 400 400 1. USA Sieve Series - ASTM Specification E-11:70 2. Tyler Standard Screen Scale Sieve Series. 3. Canadian Standard Sieve Series 8-GP-1d. 4. British Standards Institution, London BS-410-62. 5. French Standard Specifications, AFNOR X-11-501. 6. German Standard Specification DIN 4188.

25

Alternate

710 µm

*Standard

USA1

38 µm

45 µm

53 µm

63 µm

75 µm

90 µm

150 µm 125 µm 106 µm

180 µm

300 µm 250 µm 212 µm

355 µm

600 µm 500 µm 425 µm

710 µm

Standard

400

325

270

230

200

170

100 120 140

80

50 60 70

45

30 35 40

25

Alternate

CANADIAN3

350

300

240

200

170

100 120 150

85

52 60 72

44

25 30 36

22

0.040

0.050

0.063

17

18

19

20

21

0.100 0.080

22

0.125

23

24

0.200 0.160

25

0.250

26

27

0.400 0.315

28

29

0.500

0.630

FRENCH5 Opening No. (mm) 0.800 30

*These sieves correspond to those recommended by ISO (International Standards Organisation) as an International Standard and this designation should be used when reporting sieve analysis intended for international publication.

45 µm

53 µm

63 µm

75 µm

90 µm

l50 µm 125 µm 105 µm

180 µm

300 µm 250 µm 210 µm

355 µm

600 µm 500 µm 420 µm

710 µm

BRITISH4 Nominal Nominal aperture Mesh No.

50 µm 45 µm 40 µm

71 µm 63 µm 56 µm

100 µm 90 µm 80 µm

125 µm

160 µm

200 µm

250 µm

315 µm

400 µm

500 µm

0.630 µm

Opening 800 µm

GERMAN6

MATHEMATICAL TABLES AND CONVERSION FACTORS

Field Geologists’ Manual

Index Abbreviations, list, 9 minerals and rocks, 9, 249 petroleum logs, 13 Abrasive rounding classes, 54 Abundance, of elements, 64 trace elements in soils, 65 Acid tube survey, 360 Addresses, air photo suppliers, 169 Geological Surveys and Universities, 363 map suppliers, 169 Age determination, sample weight, 70 Airborne geophysical surveys, 353 Air photographs, scale formula, 282 scale nomogram, 282 suppliers, 169 Aluminium, commercial factors, 90 field chemical tests, 83 Analyses, detection limits, 68 instructions, 71 suggested methods, 68 Antimony, commercial factors, 91 field chemical tests, 83 Apparent dip, 276 Area, formulae, 272 nomogram, 178 one minute sub-blocks, 173 Arenites, classification, 51 Arsenic, commercial factors, 92 field chemical tests, 83 Asbestos, commercial factors, 92 field chemical tests, 83 Atomic numbers, 62 Atomic weights, 62 Australian Stock Exchanges, reports, 6 Barium, commercial factors, 92 field chemical tests, 83 Bedding thickness terminology, 55 Beryllium, commercial factors, 93 field chemical tests, 83 Bibliography, commercial ores, 121 economic geology, 164 geological reports, 19 mining geology, 164 structural geology, 269 Bismuth, commercial factors, 93 field chemical tests, 84 Boron, commercial factors, 93 field chemical tests, 84 Bromine, commercial factors, 94 Bulking factors, 295

Field Geologists’ Manual

Cadmium, commercial factors, 94 field chemical tests, 84 Caesium, commercial factors, 94 Calcium, commercial factors, 94 field chemical tests, 84 Calendar, 368 Carbonate sediments, classification, 52 geotechnical classification, 308 Carbonates, field chemical tests, 84 C.G.S. units from SI units, 337 Chemical tests, elements and minerals, 83 Chromium, commercial factors, 95 field chemical tests, 85 Circular orifice weirs, 326 Clay, commercial factors, 95 field chemical tests, 85 soils, description, 306 Coal, classification, 140 commercial factors, 97 graphic representation, 253 patterns for maps, 251 reserve reporting, 134 Cobalt, commercial factors, 98 field chemical tests, 85 Code, for consultants, 4 of ethics, 1 Colours, geological maps, facing p. 254 Columbium, see niobium Commercial factors, ores, 90 Compositions, minerals, 21 Compound interest, factors, 144 formulae, 142 Conductivity, soil, 313 Consultants, code, 4 Contouring device, stereonet, 287 Contour interval, recommended, 176 Conversion factors, elements to compounds, 63 foreign units, 388 Imperial to SI map scales, 175 Imperial to SI units, 384 pressure, 323 pumping, 324 rare units, 388 SI to C.G.S. units, 337 SI to Imperial units, 384 Copper, commercial factors, 98 field chemical tests, 85 Crystal system, minerals, 21 Cylindrical tanks, volume, 323 Daylight, southern hemisphere, 367

391

INDEX

Defects in rocks, 297 Degree, latitude, 171 longitude, 171 Density, minerals, 21, 37, 340 rocks, 295, 339 Detection limits, analytical methods, 68 Diamond, commercial factors, 100 field chemical tests, 86 indicator minerals, 45 reporting of mineralisation, 139 Dielectric constants, 348 Dip angle, apparent, 276 vertical exaggeration, 269 Discontinuity surfaces, aperture, 296 spacing, 296 Dolomite, commercial factors, 108 field chemical tests, 84 Down-hole survey, calculations, 359 geophysical methods, 353 Drillhole, acid tube surveys, 360 coordinates, 359 core diameter, 357 core sampling, 71 core volume, 357 diameter, 357 dip determination, 360 elevations, 359 logging, 362 sample packaging, 71 true width calculation, 361 volume, 357 Dynamic penetration, test, 310 Earthquake magnitude and intensity, 354 Electromagnetic survey, methods, 342 values, 343 Elements, abundance, 64 alphabetical list, 62 associations in mineral deposits, 66 atomic weights, 62 field chemical tests, 83 pathfinder, 66 periodic table, 61 symbols, 62 to compounds, conversion factors, 63 trace, in soils, 65 valences, 62 Elevation, field grid, 278 Engineering geology, field methods, 289 laboratory methods, 290 Environment, care during exploration, 77 Environmental impact statements, guidelines, 80 Equal angle stereonet, 284, 285 Equal area stereonet, 286 Ethics, code of, 1

392

Evaluation, mine, 163 Expansion factors, 295 Facies diagram, metamorphic, 48 Faults, classification, 266 Feldspars, field chemical tests, 86 Flame tests, 83 Flow, circular orifice weirs, 326 v-notch weirs, 327 water pipes, 322 Fluorite, commercial factors, 102 Folds, classification, 267, 268 Formal stratigraphic terms, 255 Formulae, airphoto scale, 282 area, 272, 274 perimeter, 272 triangles, 271 volume, 274 Gallium, commercial factors, 94 Gemstones, commercial factors, 102 field chemical tests, 86 Geocentric Datum of Australia, 172 Geochemical analyses, detection limits, 68 suggested methods, 68 Geochemical sampling, general notes, 70 Geological Surveys, addresses, 363 Geological maps, colours, facing p. 254 index, 165 patterns for rock types, 251 stratigraphic symbols, facing p. 254 suppliers, 169 symbols, 192 Geological time scale, 180 Geophysical surveys, conversion factors, 337 survey methods, 338-353 Germanium, commercial factors, 94 Gold, commercial factors, 103 field chemical tests, 86 sample parameters, 123, 124 Grade (slope), per cent, 277 Gradient, 277 Grain size, igneous rocks, 43 sedimentary rocks, 54 Grains, percentage diagrams, 56 Graph paper, mm ruling, 370 probability, 76 triangular, 371 Graphite, commercial factors, 105 Gravity, survey methods, 338 values, 339-341 Grid spacing, field conversion table, 278 Gypsum, commercial factors, 94

Field Geologists’ Manual

INDEX

Hafnium, commercial factors, 105 Hardness, minerals, 21-36 Heavy liquids, description, 40 Hydraulic properties of rocks, 313, 314 Hydrogeologists, Association of, 317 Australian, 317 Igneous rocks, classification, 42, 43 colour index, 43 grain size, 43 Indium, commercial factors, 94 Induced Polarisation, survey methods, 342 values, 343-348 Industrial minerals, commercial factors, 105 Interest, compound, factors, 144 formulae, 142 Intersection of planes, determination, 283 International System of Units (SI), 375 Iodine, commercial factors, 106 Iron, commercial factors, 106 field chemical tests, 86 Irrigation water, standards, 334 Landslides, classification, 300 Lead, commercial factors, 107 field chemical tests, 86 Limestone, commercial factors, 94 Lithium, commercial factors, 107 field chemical tests, 86 Lithostratigraphic nomenclature, 255 Livestock water quality, 332 Magnesium, commercial factors, 108 field chemical tests, 87 Magnesite, commercial factors, 109 Magnetic, declination maps, 165 properties, 341-342 survey methods, 341 susceptibilities, 341 Manganese, commercial factors, 109 field chemical tests, 87 Mapping, check list, 265 symbols, 192 Maps, area estimation, 178 fractional and Imperial scales, 175 fractional scales and areas, 176 index to 1:250 000 series, 165 magnetic declination, 165 suppliers, 169 Mechanical properties, rocks, 293 Mercalli scale, 354

Field Geologists’ Manual

Mercury, commercial factors, 109 field chemical tests, 87 Mesh designations, 389 Metamorphic rocks, classification, 49 facies diagram, 48 outcrop check list, 265 patterns for maps, 252 Metric conversion, factors, 384 recommended practice, 376 Metric system (SI), 375 Mica, commercial factors, 110 Mine evaluation data, 163 Mineral deposit, check list, 265 geochemical signature, 66 Mineral exploration, environmental care, 77 methods, 162 Minerals, abbreviations, 9, 249 composition of, 21 crystal system, 21 density, 21, 37 field chemical tests, 83 hardness, 21 index, 21 magnetic susceptibilities, 341-342 resistivities, 343-347 Mining company reports to ASX, 6 Molybdenum, commercial factors, 110 field chemical tests, 87 Nickel, commercial factors, 111 field chemical tests, 87 Niobium, commercial factors, 112 field chemical tests, 87 Nomenclature, stratigraphic, 255 Occupational health and safety, 372 Old workings, safety precautions, 364 One minute blocks, area, 173 Ore reserves, JORC code, 125 Ores, commercial factors, 90 resistivities, 344-345 Orifice weirs, 326 Orthographic stereonet, 284 Outcrop information check list, 265 Paper, standard sizes, 8-9 Particle size, and sample weight, 122 for gold assays, 123, 124 pyroclastic rocks, 44 sedimentary rocks, 54 Pathfinder elements, 66 Penetration resistance, test, 310 Percentage of grains diagrams, 56 Perimeter, formulae, 272

393

INDEX

Periodic table, 61 Permeability, soil, 313 Phosphates, commercial factors, 112 field chemical tests, 87 Pipes, flow rates, 322 Platinoids, commercial factors, 113 field chemical tests, 88 Plutonic rocks, classification. 42 Potassium, commercial factors, 113 field chemical tests, 88 Pressure, conversion factors, 323 head of water, 328 Probability graph paper, 76 Proofs, symbols for correcting, 17 Pumping, conversion factors, 324 Pyroclastic rocks, classification, 44 particle size, 44 Pyrophyllite, commercial factors, 116 Radioactive, background, 352 isotopes, 349 minerals, 351 series, 350-351 Radio alphabet, 366 Radiometric, survey methods, 349 values, 349-352 Rare earths, commercial factors, 114 Regolith terminology, 57 Reports, on ore reserves, 125 to Australian Stock Exchanges, 6 Resistance to abrasion, 54 Resistivity, survey methods, 342 values, 343-347 Rhenium, commercial factors, 115 Richter scale, 354 Roundness of grains, 53 Rubidium, commercial factors, 115 SI units, 375 conversion to Imperial units, 384 Safety, precautions in old workings, 364 The AusIMM principles, 372 Salt, commercial factors, 115 Sample, packaging, 71 preparation, 71 weight, 70, 122-124 Sampling, geochemical, 70 Scales, Imperial equivalents, 175 and plan areas, 176 Schmidt impact value, 291 Schmidt stereonet, 286 Scleroscope hardness, 291 Screen sizes, 389

394

Sedimentary structures, 55 Seismic, survey methods, 352 values, 352-353 Selenium, commercial factors, 115 Sieves, standard sizes, 389 Silica, commercial factors, 115 Silver, commercial factors, 107 field chemical tests, 88 Slope angle, 277 Sodium, commercial factors, 115 field chemical tests, 88 Soil, classification, 306 consistency terms, 309 description, 305 hydraulic conductivity, 313 moisture content, 309 penetration test, 310 permeability, 313-315 trace-element levels, 65 Sphericity, rock particles, 53 Stadia, formula, 280 tables, 281 Statistical terms and symbols, 72 Steatite, commercial factors, 116 Stereonet contouring device, 287 Stereonets, 284-286 Stratigraphic nomenclature, 255 Stream sediment sampling, 70 Strontium, commercial factors, 116 field chemical tests, 88 Structures, faults, 266 folds, 267 sedimentary, 55 Stock Exchange reports, 6 Sub-block, one-minute, area, 173 Sulphides, field chemical tests, 88 Sulphur, commercial factors, 116 Symbols, coal seams, 253 degree of weathering, 294 for correcting proofs, 17 geological maps, 192 minerals and rocks, 251 statistical, 72 stratigraphic, facing p. 254 Talc, commercial factors, 116 Tangent vector method, intersection of two planes, 283 Tanks, volume, 323 Tantalum, commercial factors, 112 field chemical tests, 88 Tellurium, commercial factors, 117 field chemical tests, 88 Terrigenous sediments, classification, 52 Thallium, commercial factors, 117

Field Geologists’ Manual

INDEX

Theodolite, checking, 280 Thorium, commercial factors, 114 Three point problem, 283 Time scale, geological, 180 Tin, commercial factors, 117 field chemical tests, 88 Titanium, commercial factors, 118 field chemical tests, 88 Topographic maps, suppliers, 169 Trace elements, crustal abundance, 64 abundance in soils, 65 geochemical associations, 66 Triangles, formulae, 271 Trigonometric functions, 373 True width nomogram, 179 Tungsten, commercial factors, 119 field chemical tests, 89 Universities, addresses, 363 Uranium, commercial factors, 119 field chemical tests, 89 V-notch weirs, 327 Valence states of elements, 62 Vanadium, commercial factors, 121 field chemical tests, 89 Vermiculite, commercial factors, 110

Field Geologists’ Manual

Volcanic rocks, classification, 43 Volume, formulae for, 274 of cylindrical tanks, 323 of pipes, 321 Water, analysis, 328 domestic, standards, 331 flow from pipes, 322 head pressure, 328 irrigation, standards, 334 livestock, standards, 332 pressure, 328 sampling procedure, 328 Water requirements, 319 standards, 331-335 Weathering, terms and symbols, 294 Weirs, circular orifice, 326 v-notch, 327 Windmill, pumping capacity, 320 Wulff stereonet, 285 Youngs modulus, 291 Zinc, commercial factors, 107 field chemical tests, 89 Zirconium, commercial factors, 118 field chemical tests, 89

395