Table Of ContentFurther titles in this series
1.I.L. ELLIOTT and W.K. FLETCHER
GEOCHEMICAL EXPLORATION 1974
2.P.M.D. BRADSHAW
CONCEPTUAL MODELS IN EXPLORATION GEOCHEMISTRY
The Canadian Cordillera and Canadian Shield
3. G.J.S. GOVETTandM.H. GOVETT
WORLD MINERALS SUPPLIES
Assessment and Perspective
4. R.T. SHUEY
SEMICONDUCTING ORE MINERALS
5. J.S. SUMNER
PRINCIPLES OF INDUCED POLARIZATION FOR GEOPHYSICAL
EXPLORATION
6. R.A. RICH, H.D. HOLLAND and U. PETERSEN
HYDROTHERMAL URANIUM DEPOSITS
l.J.G. MORSE
NUCLEAR METHODS IN MINERAL EXPLORATION AND
PRODUCTION
8. M. KUZVARTand M. BÖHMER
PROSPECTING AND EXPLORATION FOR MINERAL DEPOSITS
Developments in Economic Geology, 9
GEOCHEMICAL EXPLORATION 1976
Proceedings of the Sixth International Geochemical Exploration Symposium
held in Sydney, N.S.W., Australia, August 1976 during the 25th International
Geological Congress
Edited by
C.R.M. BUTT
Division of Mineralogy, Commonwealth Scientific and Industrial Research Organization,
Wembley, Western Australia
and
I.G.P. WILDING
Australian Anglo American Limited, Perth, Western Australia
Association of Exploration Geochemists
Special Volume No. 6
Reprinted from the Journal of Geochemical Exploration, Volume 8, No. 1/2
ELSEVIER SCIENTIFIC PUBLISHING COMPANY
Amsterdam — Oxford — New York 1977
ELSEVIER SCIENTIFIC PUBLISHING COMPANY
335 Jan van Galenstraat
P.O. Box 211, Amsterdam, The Netherlands
Distributors for the United States and Canada:
ELSEVIER NORTH-HOLLAND INC.
52, Vanderbilt Avenue
New York, N.Y. 10017
Library of Congress Cataloging in Publication Data
International Geochemical Exploration Symposium, 6th,
Sydney, 1976.
Geochemical exploration, 1976.
(Developments in economic geology ; 9) (Special
volume - Association of Exploration Geochemists ; no. 6)
"Reprinted from the Journal of geochemical exploration,
volume 8, no. l/2."
Bibliography: p.
1. Geochemical prospecting—Congresses. I. Butt,
C. R. M. II. Wilding, I. G. P. III. Association of
Exploration Geochemists. IV. Title. V. Series.
VI. Series: Association of Exploration Geochemists.
Special volume - Association of Exploration Geochemists ;
no. 6.
TN270.I63 1976 622« .1 77-I6/M
ISBN O-/4M-41653-6
ISBN 0-444-41653-6 (Vol. 9)
ISBN 0-444-41250-6 (Series)
© Elsevier Scientific Publishing Company, 1977
All rights reserved. No part of this publication may be reproduced, stored in a
retrieval system or transmitted in any form or by any means, electronic, mechan-
ical, photocopying, recording or otherwise, without the prior written permission
of the publisher, Elsevier Scientific Publishing Company, P.O. Box 330, Amsterdam,
The Netherlands
Printed in The Netherlands
FOREWORD
This is the first occasion on which the papers presented at an International
Geochemical Exploration Symposium have been published in the Journal of
Geochemical Exploration. We hope that, by this means, the papers presented
at the Symposium will be available to the widest possible audience.
Thirty of the papers read at the Symposium are presented here; of the
remainder, some are published elsewhere and others are not yet available.
Extended abstracts of all papers selected for presentation have, however,
been published in the Abstracts (Volume II, Section 10B) of the 25th Inter-
national Geological Congress, 1976. The manuscripts were reviewed by many
people and we wish to extend our thanks to them for the care which was
taken in making such reviews and for the constructive nature of their com-
ments. We also wish to acknowledge the cooperation of several authors who
generously reduced the lengths of their papers to meet the space limitations
set for this Proceedings issue.
The Proceedings of the workshop were not formally recorded, in order to
promote freer discussion. However, the contributions of the lead speakers
have been summarized in Newsletter No. 21 of the Association of Explora-
tion Geochemists (January 1977).
C.R.M. BUTT
I.G.P. WILDING
LIST OF CONTRIBUTORS
Ali, I.S., 305 Guy, B.B., 169
Antweiler, J.C., 17 Hart, M.K., 283
Bampton, K.F., 169 Honey, F., 457
Barakat, N., 305 Lakin, H.W., 31
Barnes, H.L., 105 Lavery, N.G., 105
Beuge, P., 415 Leggo, M.D., 431
B<Alviken, B., 457 Levine, S.R., 457
Boyle, D.R., 49 Lyon, R.J.P., 457
Butt, C.R.M., 283 Moeskops, P.G., 247
Cadigan, R.A., 381 Neuerburg, G.J., 31
Cagatay, M.N., 49 Nickel, E.H., 235
Campbell, W.L., 17 Osmond, J.K., 365
Cathrall, J.B., 31 Pilot, J., 415
Christensen, S.M., 219 Prélat, A., 457
Collins, A.R., 169 Rattigan, J.H., 203
Cowart, J.B., 365 Rosier, H.J., 415
Cox, R., 189 Russell, D.W., 483
Curtis, R., 189 Ryall, W.R., 73
Devine, S.B., 397 Scott, K.M., 153
Eissa, E.A., 305 Sears, H.W., 397
El Shazly, E.M., 305 Seccombe, P.K., 117
Emara, H.H., 305 Shaltout, S., 305
Felmlee, J.K., 381 Sharaf, F.S., 305
Foy, M.F., 357 Sherrington, G.H., 325
Friedrich, G.H.W., 219 Sinclair, I.G.L., 139
Gardner, K.A., 283 Smith, B.H., 259
Gatehouse, S., 483 Stigzelius, H., 473
Taylor, G.F., 153
Gedeon, A.Z., 283
Thornber, M.R., 235
Gersteling, R.W., 203
Tischendorf, G., 415
Gingrich, J.E., 357
Tonkin, D.G., 203
Glasson, K.R., 169
VanMoort, J.C., 483
Gott, G.B., 31
Watterson, J.R., 31
Govett, G.J.S., 3
Wenrich-Verbeek, K.J., 337
Gulson, B.L., 85
SYMPOSIUM COMMITTEES
Organizing Committee
J.F. Gilfillan J.F. Gilfillan and Associates Pty. Ltd.
C.R.M. Butt CSIRO Division of Mineralogy
R. Cox Placer Exploration Ltd.
J.J. Hobbs New South Wales Geological Survey
N.J. Marshall Australian Selection Ply. Ltd.
A.L. Mather Geochemical and Mineralogical Laboratories Pty. Ltd.
W.R. Ryall CSIRO Division of Mineralogy
G.F. Taylor CSIRO Division of Mineralogy
J.R. Wilmshurst CSIRO Division of Mineralogy
Technical Programme Committee
C.R.M. Butt CSIRO Division of Mineralogy
R. Davy Geological Survey, Western Australia
R.H. Mazzucchelli Western Mining Corporation Ltd.
R.E. Smith CSIRO Division of Mineralogy
I.G.P. Wilding Australian Anglo American Ltd.
INTRODUCTION
The Sixth International Geochemical Exploration Symposium was held in
August 1976 in Sydney, New South Wales, Australia, as part of the 25th In-
ternational Geological Congress. The technical programme of the Sympo-
sium was organized by the Association of Exploration Geochemists, within
the general format of the Congress. The Association assumed responsibility
for Congress Section 10B by including it within the Symposium programme.
It was most appropriate that the Symposium be held in Australia, since Aus-
tralia has the third highest number of Association members, after the U.S.A.
and Canada, and is a country in which geochemical techniques of explora-
tion are widely used and have a considerable degree of importance. Bearing
in mind the high cost of travel to and within Australia, the meeting was
linked with the IGC to encourage greater participation by geochemists from
overseas but, as a result, had to compete with the numerous other technical
sessions for the available audience. In the event, the Congress was attended
by 2300 delegates of whom up to 250 attended individual Symposium ses-
sions. Incidental to this link with IGC, the Association was relieved of the
task of arranging accommodation, field excursions etc.
The Symposium was opened by Mr. I.E. Newnham, Director of the Min-
erals Research Laboratories of the Commonwealth Scientific and Industrial
Research Organization (CSIRO). The technical programme commenced with
an address by Professor G.J.S. Govett, University of New Brunswick, Cana-
da, the President of the Association of Exploration Geochemists. There fol-
lowed 38 papers, mainly concerned with exploration for mineral deposits
in deeply weathered terrain and for energy resources, with the use of pri-
mary dispersion in exploration and with miscellaneous topics, including ana-
lytical techniques. A final half-day session was devoted to a workshop enti-
tled "Threshold - fact or fiction".
On behalf of the Association, we would like to thank all those who pre-
sented papers, for the success of the meeting was due to their efforts. Special
thanks are also due to the lead speakers at the workshop — Dr. A.L. Mather,
Mr. N.J. Marshall, Dr. M.A. Chaffee and Dr. D.H. McKenzie and to all
those who contributed to discussions. Regrettably, a number of contribu-
tors withdrew from the Symposium at a late stage a problem which beset
the whole Congress. We are indebted to Dr. T. Wignall and Dr. S.H.U. Bowie
who agreed to give papers at very short notice to fill gaps in the programme.
Daily Organizers and the Chairmen of Sessions are thanked for their assis-
tance with the smooth running of the meeting. We would also like to thank
all those who submitted synopses of papers; constraints of time and space
prevented the inclusion of many interesting contributions.
2 INTRODUCTION
The organization and the smooth running of such a Symposium is due to
the efforts of many people for a period in excess of two years. While the task
was not eased by the necessity of having the Organizing Committee in
Sydney and a Technical Programme Committee in Perth, the cooperation of
all concerned to overcome this problem is gratefully acknowledged. On
behalf of the Association, we would also like to thank members of both
Committees for their enthusiasm in carrying out the numerous tasks that
ensured the success of the meeting. We benefitted greatly from the ready
cooperation of the IGC Organizing Committee and its staff, particularly
the Secretary-General, Mr. A. Renwick, who afforded us every assistance.
The organization of the meeting was only made possible by the generous do-
nation of time and facilities from the employers of the Committee members.
We wish to acknowledge the following organizations who made staff avail-
able for reception and publication sales duties through the Congress: Amoco
Minerals Australia Ltd., Australian Oil and Gas Corporation Ltd., Australian
Selection Pty. Ltd., CSIRO, Geological Survey of N.S.W., Getty Oil Develop-
ment Ltd., J.F. Gilfillan and Associates Pty. Ltd., Pancontinental Mining
Ltd. and Placer Exploration Ltd. We would also like to record our thanks to
the Secretarial staff of the CSIRO Division of Mineralogy, particularly Mrs.
Cheryl Harris who, with great speed and accuracy, typed much of the corre-
spondence and other paperwork and retyped many of the extended abstracts
and complete manuscripts prior to their submission to the publishers.
The Seventh International Geochemical Exploration Symposium is to be
held in Golden, Colorado, U.S.A. in April 1978 and we look forward to an-
other stimulating and enjoyable meeting there.
J.F. GILFILLAN
Chairman, Organizing Committee
C.R.M. BUTT
Convenor, Section 10B, 25th IGC
Journal of Geochemical Exploration, 8 (1977) 3 16 3
© Elsevier Scientific Publishing Company, Amsterdam — Printed in The Netherlands
Presidential Address
WORLD MINERAL SUPPLIES - THE ROLE OF EXPLORATION GEO-
CHEMISTRY
G.J.S. GOVETT*
President, Association of Exploration Geochemists
INTRODUCTION
I am immensely pleased to have this opportunity to welcome you on be-
half of the Association of Exploration Geochemists to the Sixth Interna-
tional Geochemical Exploration Symposium. It is the first of these biennial
symposia to be held in the southern hemisphere and is a remarkable demon-
stration of the international strength of the Association.
The choice of an appropriate theme for this address was not easy; it was
clear that mild exhortations and philosophical musings would not be ade-
quate without "disguising" them by offering something more substantial.
The topic I have chosen — mineral supplies and geochemistry — is very much
a reflection of my own interests, but I hope it may have broad appeal since
the adequacy of mineral supplies is becoming the concern of everyone — and
¡should be of special concern to exploration geochemists.
The world's literature is full of papers and articles that debate the ade-
quacy of mineral resources to sustain the present living standards in industri-
alized countries and that argue the possibilities of resources being available
to permit the numerically less developed majority of the world to attain
similar standards. Much of the argument and disagreement stems from the
failure of many of the protagonists to distinguish clearly between mineral
reserves and mineral resources.
Mineral reserves are ephemeral figures of the moment — an estimate, of
varying reliability, of the tons (pounds, ounces, grams) of a particular com-
modity that is identified and measured in the ground and which can be re-
moved economically and processed at today's costs and prices and with
today's technology. Reserves are dynamic figures that change constantly in
response to price, technology, development work and exploration success.
Mineral resources, on the other hand, include not only reserves, but also in-
clude identified mineral deposits that are not now economically workable
(by virtue of grade, mineralogy, lack of appropriate technology, current
prices), plus all unknown mineral deposits yet to be discovered. Mineral re-
sources — even if we do not know their magnitude — are conceptually fixed
* Present address: Department of Geology, University of New Brunswick, Fredericton,
N.B., Canada.
4 G.J.S. GOVETT
by past geological events. Fundamentally, the absolute limit of resources of,
say, copper is the crustal abundance of copper in the earth's crust; if we had
the appropriate technology available and could afford the cost, the resources
of copper would be virtually limitless. The dynamic relation between resour-
ces and reserves as a function of price, grade, technology and exploration
success is shown schematically in Fig. 1.
measured reserves
indicated reserves
inferred reserves
non-exploitable
deposits
current economic
recoverable level
lowest grade
considered
possible for
some defined
time period
exploration success-
Fig. 1. Schematic illustration showing the dynamic relation between reserves and resour-
ces. (From Govett and Govett, 1974; originally published in Resources Policy, vol. 1, p.
53.)
Some encouragement for the future is given by the historical trend of
copper production (Fig. 2).The grade has decreased along an approximate
negative exponential curve (i.e., the low-grade copper deposits mined today
and now regarded as reserves would, even at the beginning of this century,
have been classified — if known — as resources). Until recently, cost has also
decreased. A related trend of utmost importance is that, although produc-
tion is steadily increasing, reserves are keeping pace.
The debate on the adequacy of world mineral resources should now prop-
erly be a debate about the adequacy of mineral exploration technology to
find mineral deposits, and the adequacy of mining and mineral processing
technology to convert mineral deposits into orebodies from which raw ma-
