Table Of ContentGold Metallogeny
and Exploration
Edited by
R.P. FOSTER
Senior Lecturerin Economic Geology
DepartmentofGeology
University ofSouthampton
Blackie
Glasgow and London
Black-ieandSonLtd
Bishopbriggs.GlasgowG642NZ
~d
7LeicesferPlace. London WC2H7BP
e
1991 Black.ieandSonLtd
Softcoverreprintofthehardcover 1stedition 1991
First published 1991
Allrightsreserved.
Nopartofthispublicotionmaybereproduced,
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inanyformorbyanymeans-graphic.
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BritishLibraryCataloguingin PublkalionDala
Goldmetallogenyandexploration.
J. Golddeposits
I. Foster,R. P,
553.41
ISBN-13:978-1-4612-7837-5 e-ISBN-13:978-1-4613·0497·5
001: 10.10071978-1-4613-0497-5
PhototypesettingbyPureTechCorporation,Pondicherry,India
Preface
Within the last decade, the high and continuing demand for gold has prompted a
global gold rush on ascaleneverbefore seen, noteven in theheadydays ofBallarat,
CaliforniaandtheYukon. Goldisbeingsoughtoneverycontinentand,withveryfew
exceptions, in every country around the world. Such interest and fierce competition
has demanded considerable innovation and improvement in exploration techniques
paralleled by a rapid expansion of the geological database and consequent genetic
modellingfor the manydifferenttypesofgolddeposits now recognized.
This proliferation of data has swamped the literature and left explorationist and
academic alike unable to sift more than a small proportion of the accumulating
information. This new book represents an attempt to address this major problem by
providingsuccinctsynthesesofallmajoraspectsofgoldmetallogenyandexploration,
ranging from the chemical distribution of gold in the Earth's crust, and the
hydrothermal chemistry of gold, to Archaean and Phanerozoic lode deposits,
epithermal environments,chemicalsediments, and placerdeposits, and culminates in
chapters devoted to geochemical and geophysical exploration, and the economics of
gold deposits. Each chapter is written by geoscientists who are acknowledged
internationally in their respective fields, thus guaranteeing a broad yet up-to-date
coverage. In addition, each chapter is accompanied by reference lists which provide
readers withaccess tothemostpertinentanduseful publications.
Quite clearlythisbook is not intendedtobe the ultimate authoritativestatementon
gold metallogeny and exploration, nor can it hope to embrace all aspects of gold
mineralization. Foraccess to awealthofnew informationthe readerisencouragedto
turntotherelevantjournalsandtotheexcellentpublicationsarisingfrom many major
symposia held within the last decade. The more recent of these include the
proceedingsoftheGold'86meetinginToronto,thePacificRimCongress '87inGold
Coast, Australia,and theGold '88 symposiumheldin Melbourne.
The stimulusprovided bythe demandfor goldin the 1980shasopened upexciting
new avenues of research and generated a wealth of hard facts, innovative ideas,
conceptual models, and advances in instrumental techniques. The resultantdatabases
and the success arising from this surge in exploration are a timely reminder to the
world at large ofthe importance ofapplied research and ofexploration underpinned
by sound science. I hope that this volume provides both a useful state-of-the-art
review and an insight into the scientific and industrial excitement inspired by the
1980sgoldrush.
Finally, I should like to thank the following for providing the all-important
refereeing of contributions which is essential to ensure the quality of such a
publication: B.R Berger, H.F. Bonham, Jr., C.A. Boulter, P.R.L. Browne, A.H.C.
Carter, H. Colley, D.S. Cronan, MJ. de Wit, P.I. Eimon,WR Fitches, A.O. Fuller,
A.P. Gize, D.D. Hawkes, J.W Hedenquist, U. Hemley, R.W Henley, P. Lhotka, A.
Panteleyev,D.A. Pretorius,RH. Sillitoe,M. Smith,D.A.V. Stow,J.F.H. Thompson.
R.P.F.
Contributors
DrW.C. Bagby USGeologicalSurvey, Menlo Park,California, USA
WilliamBagbyreceivedaPh.D.inEarthSciencefrom theUniversityofCalifornia,SantaCruz,
onpetrogeneticresearchofTertiaryvolcanicrocksintheSierraMadreOccidental,Mexico. His
mining industry experience includes porphyry copper exploration, geologic evaluation of
volcanic-hosted uraniumdeposits, epithermal silvervein deposits, and hotspringgolddeposits.
Researchdoneatthe USGShasbeenfocusedongolddeposits inNevadaandamineral-resource
assessment of Costa Rica. Dr. Bagby has served as a programme coordinator for the USGS
Strategic and Critical Minerals Program and presently is serving as the Chiefofthe Branch of
WesternMineralResources.
DrB.R.Berger USGeologicalSurvey,Spokane, Washington, USA
Byron Bergerhas been involved inexploration for and research onepithermal and Carlin-type
golddepositssince 1971,aftercompletinganMS ingeologyattheUniversityofCalifornia,Los
Angeles,andaBAineconomicsatOccidentalCollege,LosAngeles.InitiallywithConocoInc.in
explorationandmineralsexplorationresearch,hejoinedtheUSGS,OfficeofMineralResources
in 1977.HisindustrialexperiencefocusedonCarlin-typedepositsinnorthernNevada,andduring
histenurewiththeUSGShehasconductedresearchonvolcanic-rock-relatedepithermaldeposits
in the Western Great Basin and Pacific Northwestern United States. Administratively, he has
servedasanAdjunctProfessor,UniversityofColorado,andChief,BranchofGeochemistryinthe
USGS,andiscurrentlyDeputyChief,OfficeofMineralResourcesandontheEditorialBoardof
EconomicGeology.
DrW.B. Coker GeologicalSurveyofCanada, Ottawa,Canada
Bill Coker graduated from Carleton University in 1971 with an Honours B.Sc. in Geology.
Specializingingeochemistry,hereceivedhisPh.D.fromQueen'sUniversity,Ontarioin 1974.He
hasover20yearsexperiencewiththemineralexplorationindustry,mostrecentlywithKiddCreek
Mines Ltd.,and ingovernmentresearch. DrCokeriscurrentlyaResearchGeochemist with the
Geological Survey of Canada conducting research on geochemical methodologies, primarily
overburdengeochemistry,inglaciatedterrains.
DrJ.H.Crocket DepartmentofGeology,McMasterUniversity,Hamilton, Ontario,
Canada
James Crocket is a graduate of the University ofNew Brunswick, Oxford University, and the
Massachusetts Institute of Technology where he obtained a Ph.D. in 1961. He joined the
Department ofGeology at McMaster University in Hamilton, Ontario, in the same year and is
currently involved in teaching economic geology and geochemistry at McMaster. Much ofhis
researchisconcernedwithArchaeangolddepositsandplatinumgroupmetalmineralization,with
modestdiversions intotheCretaceousrrertiaryboundaryproblem.Dr. CrocketisaFellowofthe
GeologicalAssociationofCanada.
CONTRIBUTORS v
DrR.P. Foster DepartmentofGeology, University ofSouthampton, UK
BobFostergraduatedfrom the UniversitiesofDurham in 1970(B.Sc.)and Manchesterin 1973
(Ph.D.) and was then employed as a mine and exploration geologist by Falcon Mines Ltd in
Rhodesia (now Zimbabwe). In 1977 he moved to the Institute of Mining Research at the
University of Rhodesia (Zimbabwe) where he was involved in problem solving and applied
research incollaboration with the local mining industry. In 1984 he moved to the University of
Southampton,whereheisnowSeniorLecturerinEconomicGeologyandalsoactsasaconsultant
ongoldminingandexplorationinEurope,Africa,andtheMiddleEast.
Professor DJ. Groves Key Centrefor Teaching andResearch in Strategic Mineral
Deposits, UniversityofWestern Australia,Australia
DavidGroves iscurrentlyProfessor(personalchair) inGeologyandDirectorofthe KeyCentre
for Strategic Mineral Deposits, Geology Department, University ofWestern Australia. He is a
B.Sc. Honours (First Class) and Ph.D. graduate of the University of Tasmania. Formerly a
geologistwiththeGeologicalSurveyofTasmania,wherehehadresearch interestsinspecialized
granitoid and tin deposits, ProfessorGroves joined the University in 1971. Since that time, his
primary interest has been Archaean metallogeny, with particular emphasis on komatiite
associated Ni-Cudepositsand mesothermalgolddeposits. Currentlyhe headsateamoften staff
and postdoctoral fellows and about 20 postgraduate students who are mostly researching
Precambrianoredeposits.
DrP.G. Hallof ConsultantGeophysicist, Toronto, Canada
PhilipHallofattended university and graduate school at Massachusetts InstituteofTechnology,
Cambridge, Massachusetts and graduated with a Ph.D. degree in 1956. He thenjoinedMcPhar
GeophysicsLtd.,Toronto,Canada,asageophysicistandlaterbecamepresidentofthecompany.
HesubsequentlyservedaspresidentofPhoenixGeophysics Ltd. andnow works inTorontoasa
consulting geophysicist. Throughout his professional career he has specialized in the use of
electrical geophysical methods in thesearchforbasemetaldepositsandpreciousmetaldeposits,
andhas planned, supervisedandinterpretedgeophysical surveys inminingareasthroughout the
world.
DrM.D. Hannington GeologicalSurvey ofCanada, Ottawa,Canada
MarkHanningtonisagraduateofQueen'sUniversityatKingston,Ontario,andreceivedhisPh.D.
in Geology from the University of Toronto in 1989. He is currently a Visiting Fellow in the
Mineral Resources Division of the Geological Survey ofCanada, where he is studying active
hydrothermalsystemson the modernseafloorandtheirrelationshiptoancientsulphidedeposits
on land. Dr Hannington's research has focused on the geochemistry of gold in volcanogenic
massivesulphides,andprocessesofsecondaryenrichmentofgoldinsulphidegossans.
DrR.W. Henley ConsultantEconomicGeologist, Canberra, Australia
DickHenleyhashadcloseinvolvementwiththedevelopmentofunderstandingofthecontrolson
thedistribution andoriginofawide rangeofhydrothermaloredeposits forover20years. Since
obtaining his Ph.D. from the University ofManchester in 1971 he has held positions at Otago
University, New Zealand, andMemorial University, Newfoundland and from 1980was Headof
theGeothermalChemistryGroupwithinDSIRinNewZealand.From 1986to 1988,hewasChief
Scientistofthe Division ofPetrology and Geochemistry at the BureauofMineral Resources in
Canberra,andhassinceconsultedprivatelytothemineralsindustryonexploration.
VI CONTRIBUTORS
DrP.M. Herzig Institute ofMineralogy andEconomicGeology,Aachen University
ofTechnology, WestGermany
PeterHerzigreceivedhis Ph.D. in 1986from the Aachen UniversityofTechnology, where he is
now aResearchAssociateintheInstituteofMineralogyandEconomicGeology.Hehas worked
extensively on sulphide deposits in the Troodos Ophiolite and in particular on sub-seafloor
stockworksassociatedwithfossilhydrothermalsystems.Hiscurrentresearchincludesexploration
forhydrothermalventsintheIndianOceanandstudiesofthegeologyandmineralogyofsulphide
depositsinmodernback-arcbasinsoftheSouthwestPacific.
Dr C. Leduc Applied Geochemistry Branch, Bureau de Recherche Geologie et
Minerales, Orleans,France
Claudy Leduc received a Masters degree from the University ofParis. He spent several years
working for explorationcompanies in Canada and subsequently went to Tunisia where he was
mostly involvedingeochemicalexploration. He joined the BRGM in 1981 where he is now in
chargeofvariousgeochemicalexplorationprogrammes,inFranceandNorthAfrica,wherehehas
gained considerableexperience in the application ofgeochemical techniques toexplorationfor
goldandbasemetaldeposits.
ProfessorB.W.Mackenzie CentreforResourceStudies,DepartmentofGeological
Sciences, Queen'sUniversity, Kingston, Canada
BrianMackenzieisaCanadianminingengineerinterestedintheeconomicsofmineralsupply.He
received his formal education at McGill University, the University of the Witwatersrand, and
ColumbiaUniversity. Inhisearlyyears, he worked forSheepCreekMines, UnionCorporation,
theSouthAfricanDepartmentofMines,andEnergy,MinesandResourcesCanada.From1968to
1977he wasresponsibleforteachingandresearchinmineraleconomicsandwasDirectorofthe
MiningProgramatMcGillUniversity.Since1978hehasbeenaSeniorResearchAssociateofthe
CentreforResourceStudiesandaProfessorintheDepartmentofGeologicalSciencesatQueen's
University,Kingston.
ProfessorW.E.L. Minter DepartmentofGeology, University ofCape Town, South
Africa
LawrieMinterisProfessorofEconomicGeologyatthe UniversityofCapeTown.HeisaSouth
AfricanandagraduateoftheUniversityofCapeTownandtheUniversityoftheWitwatersrand.
DrMinterhasspentmostofhis careerworkingfor mineral explorationand miningcompanies,
andforthe past25 yearshas beenactivelyengagedingoldanddiamondpalaeoplacerresearch,
both in southern Africaand Brazil. He is best known for his publications on sedimentological
aspectsofWitwatersrandgoldplacers.
ProfessorB.E.Nesbitt DepartmentofGeology, UniversityofAlberta,Canada
BruceNesbittisaProfessorofEconomicGeology in theDepartmentofGeology, Universityof
Alberta,Canada. Afterreceivinghis BAin 1973from CarletonCollege,he undertook graduate
studiesineconomicgeologyandmetamorphicpetrologyattheUniversityofMichigan,receiving
his MS degree in 1976 and Ph.D. in 1979. From 1979 to 1980, he held an NSF Postdoctoral
FellowshipatPennsylvaniaStateUniversity.From1980tothepresent,hehasbeenonthestaffof
the UniversityofAlberta. DrNesbitt'searly research interestscentredon thestudyofchemical
effectsofmetamorphismonoredeposits.Morerecently,hisresearchhasfocused on thegenesis
of mesothermal Au±Ag deposits and the role of crustal fluid-flow in the generation of such
deposits.
CONTRIBUTORS VB
DrN.R. Paterson Paterson, GrantandWatson Ltd.,Toronto, Canada
NormanPatersonreceivedhisPh.D.from the UniversityofTorontoin 1955. Aftershort periods
withmajorminingandpetroleumcompanies,hewaswiththeCanadianHuntingAirborneSurvey
Group and later president of Huntec Ltd. He obtained world-wide experience in all types of
airborne,groundandmarinegeophysics,aswellas instrumentdevelopmentandmanufacture. In
1969he startedaconsultingbusiness, reorganized in 1973intoPaterson,Grantand WatsonLtd.
As a consultant he has provided advice, technical management, and interpretation services to
mining companies, governments, and aid agencies. He has managed major programmes in the
developingcountriesforCIDA, World Bank and the UN. In 1977 he was madeaFellowofthe
RoyalSocietyofCanada.
Professor S.D. Scott Marine Geology Research Group, Department of Geology,
UniversityofToronto, Canada
Steve Scott received his Ph.D. from Pennsylvania State University, where he studied sulphide
mineralogy and chemistry. He joined the University of Toronto in 1969, where he is now a
Professorin the DepartmentofGeology,and with hisstudentshas publishedextensively on the
geology and geochemistryofvolcanogenic massive sulphidesinCanadaandJapan. Since 1983,
he has been actively involved in the study of modern seafloor hydrothermal systems. He now
directstheMarineGeologyResearchGroupattheUniversityofTorontoandhasbeeninvolvedin
theOceanDrillingProgram.
Professor T.M. Seward Chemistry Division, Department of Scientific and
IndustrialResearch,LowerHutt, NewZealand
Terry Sewardobtained his B.Sc. from McMaster University in Canada and his Ph.D. from the
UniversityofManchester,UK. He wasformerlysectionleaderandseniorresearchscientistwith
theChemistryDivisionoftheNewZealandDSIR.From1976to 1978,he was anAlexandervon
Humboldt Fellow at the University of Karlsruhe (BRD). Dr Seward was visiting professor at
Pennsylvania State University in 1982 and guest professor at the Swiss Federal Institute of
Technology(ETH)inZiirichin 1988.HeisatpresentprofessorofgeochemistryattheETH. His
main research interests are in the chemistry and geochemistry of aqueous solutions at high
temperaturesandpressures.
DrW.W.Shilts GeologicalSurveyofCanada, Ottawa,Canada
William Shilts received his BA degree from DePauw University (1963), his MS from Miami
University, Ohio(1965)and his Ph.D. from Syracuse University (1970). He has worked for the
Geological Survey ofCanada since 1970 and is currently Senior Quaternary Scientist in the
TerrainSciences Division. DrShiltshas beenparticularly interested in practicalapplicationsof
research to the chemistry, mineralogy and physical properties of glacial drift, especially till.
Althoughaimedprimarilyatimprovingordevelopingtechniquesofdriftprospecting,muchofhis
recent research has been applied to problems inenvironmental geOChemistry, radioactive waste
disposal,andan improvedunderstandingoftheconfigurationoftheNorthAmericancontinental
icesheet.
DrR.H.Sillitoe ConsultantGeologist,Highgate Village, London, UK
Richard Sillitoe received his B.Sc. and Ph.D. degrees from the University ofLondon, UK and
wentontoworkasaneconomicgeologistwiththeGeologicalSurveyofChile.Duringthelast19
yearshehas workedasan independentgeologicalconsultanttointernationalminingcompanies,
foreign governmentsand internationalagenciesinsome60countriesworld-wide. Since 1979his
activitieshavebeenalmostexclusivelydevotedtogoldexploration,especially inCordilleranand
island-arcenvironments.
viii CONTRIBUTORS
Dr H. Zeegers Applied Geochemistry Branch, Bureau de Recherche Geologie et
Minerals, Orleans,France
HubertZeegers is now Headofthe ExplorationDepartmentofthe BRGM,afterhaving been in
charge of the Applied Geochemistry Branch. He received a Masters degree from the Louvain
University, Belgium, and was first employed in Burkina Faso, West Africa, as exploration
geochemist in a United Nations DevelopmentProgram, Mineral ExplorationProject. Hejoined
the BRGM in 1974, and participated in numerous exploration and research projects involving
explorationgeochemistry.Mostofhisexperiencewasgainedintropicallyweatheredterrains,and
hehasbeendeeplyinvolvedindevelopingexplorationtechniquessuitabletosuchenvironments.
Contents
1 Distribution ofgold in the Earth's crust 1
J.H. CROCKET
1.1 Introduction I
1.2 Goldinrock-formingminerals I
1.3 Goldinigneousrocks 3
1.3.1 Introduction 3
1.3.2 Generalcharacteristicsofgolddistributioninthelithosphere 3
1.3.3 Goldabundanceinmaficandultramaficrocks 6
I.3A GoldinPrecambrianrocks 7
1.3.5 Estimatesofmantlegoldabundance 8
1.3.6 Maficvolcanicrocksinnon-orogenicenvironments 8
1.3.7 Maficplutonicrocksinnon-orogenicsettings 9
1.3.8 Orogenicenvironments 10
IA Goldinsedimentsandsedimentaryrocks 10
1.4.1 Introduction 10
1.4.2 Goldinsediments II
IA.3 Goldinclasticrocks II
lAA Goldinchemicalsedimentaryrocks 12
1.5 Goldinmetamorphicrocks 12
1.5.I Introduction 12
1.5.2 Regionalmetamorphism 13
1.5.3 Granitoidintrusionsinmetamorphicterranes 14
1.6 Concludingsummary 14
1.7 Mineraldata 16
1.7.1 Explanatorynotes 16
1.7.2 Thegoldcontentofrock-formingminerals 16
1.7.3 Thegoldcontentofigneousrocks 18
1.7A Thegoldcontentofsedimentsandsedimentaryrocks 25
1.7.5 Thegoldcontentofmetamorphicrocks 28
References 30
2 The hydrothermal geochemistry ofgold 37
T.M. SEWARD
2.1 Introduction 37
2.2 Theinorganicchemistryofgold 37
2.2.1 Oxidationstates 37
2.2.2 Relativisticeffects 38
2.2.3 CoordinationchemistryofAu(l) 39
2.3 Goldcomplexinginhydrothermalsolutions 42
2.3.1 Whichcomplexesare important? 42
2.3.2 Halidecomplexesofgold(1) 43
2.3.3 Hydrolysis 45
2.3A Hydrosulphidoandsulphidocomplexes 45
