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SOCIETY OF ECONOMIC GEOLOGISTS, INC.
GOLD IN 2000CONTENTS
Gold in 2000—An Introduction S.G. Hagemann and P.E. Brown
Archean Orogenic Lode Gold Deposits S.G. Hagemann and K.F. Cassidy
Proterozoic Lode Gold and (Iron)-Copper-Gold Deposits: F.P. Bierlein and D.E. Crowe A Comparison of Australian and Global Examples
Phanerozoic Orogenic Lode Gold Deposits F.P. Bierlein and D.E. Crowe
Fluid Chemistry of Orogenic Lode Gold Deposits and J.R. Ridley and L.W. Diamond Implications for Genetic Models
Characteristics and Models for Carlin-Type Gold Deposits A.H. Hofstra and J.S. Cline
Characteristics and Genesis of Epithermal Gold Deposits D.R. Cooke and S.F. Simmons
Exploration for Epithermal Gold Deposits J.W. Hedenquist, A. Arribas R., and E. Gonzalez-Urien
Gold Deposits Related to Alkaline Magmatism E.P. Jensen and M.D. Barton
Gold-Rich Porphyry Deposits: Descriptive and Genetic Models R.H. Sillitoe and Their Role in Exploration and Discovery
Gold in Skarns Related to Epizonal Intrusions L.D. Meinert
Gold Deposits Related to Reduced Granitic Intrusions J.F.H. Thompson and R.J. Newberry
Gold in Volcanic-Hosted Massive Sulfide Deposits: D.L. Huston Distribution, Genesis, and Exploration
Gold in Sedex Deposits P. Emsbo
Witwatersrand Gold Fields: Geology, Genesis, and Exploration G.N. Phillips and J.D.M. Law
The Geodynamics of World-Class Gold Deposits: R. Kerrich, R. Goldfarb, D. Groves, and S. Garwin Characteristics, Space-Time Distribution, and Origins
The Current Status and Future of the Interface between the T.C. McCuaig and J.M.A. Hronsky Exploration Industry and Economic Geology Research
EditorsS.G. Hagemann and P.E. Brown
REvIEwS IN EcONOMIc GEOLOGY
volume 13
Society of Economic Geologists, Inc.
Reviews in Economic Geology, Vol. 13
Gold in 2000S.G. Hagemann and P.E. Brown, Editors
Additional copies of this publication can be obtained from
Society of Economic Geologists, Inc.7811 Shaffer ParkwayLittleton, CO 80127
www.segweb.org
ISBN: 978-1-629495-71-2
Antonio Arribas R.Placer Dome Exploration 240 South Rock Blvd, Suite 117 Reno, NV 89502USATel. 1.775.856.2552Fax: 1.775.856.3091E-mail: [email protected]
Mark D. BartonUniversity of ArizonaDepartment of GeosciencesCenter for Mineral ResoucesTucson, AZ 85721USATel. 1.520.621.8529Fax: 1.520.621.2672E-mail: [email protected]
Frank P. BierleinVictorian Institute of Earth and Planetary Sciences
Department of Earth SciencesMonash UniversityClayton, Victoria 3800AustraliaTel. 61.3.9905.1643Fax: 61.3.9905.4903E-mail: [email protected]
Philip E. BrownDepartment of Geology and Geophysics
University of Wisconsin-Madison1215 W. DaytonMadison, WI 53706-1692USATel. 608.262.5954Fax: 608.262.0693E-mail: [email protected]
Kevin F. CassidyAustralian Geological Survey Organisation
Canberra, ACT 2601 AustraliaTel. 61.2.6249.9578Fax: 61.2.6249.9965E-mail: [email protected]
Jean S. ClineDepartment of GeoscienceUniversity of Nevada-Las VegasBox 4540104505 Maryland Parkway Las Vegas, NV 89154-4010USATel. 1.702.895.1091Fax: 1.702.895.4064E-mail: [email protected]
David R. Cooke Centre for Ore Deposit ResearchUniversity of TasmaniaGPO Box 252-79Hobart, Tasmania 7001AustraliaTel. 61.3.6226.7605Fax: 61.3.6226.7662E-mail: [email protected]
Douglas E. CroweDepartment of GeologyUniversity of GeorgiaAthens, GA 30602USATel. 1.706.542.2382Fax: 1.706.542.2425E-mail: [email protected]
Larryn W. DiamondMineralogy and Petrology Group Institute of Geological SciencesUniversity of LeobenPeter Tunner Strasse 5A-8700 Leoben AustriaTel. 43.3842.402.450Fax: 43.3842.470.16E-mail: [email protected]
Poul EmsboU.S. Geological Survey MS 973Denver Federal CenterDenver, CO 80225USATel. 1.303.236.1113Fax: 1.303.236.1829E-mail: [email protected]
Steven GarwinNewmont Mining CorporationGeology DepartmentP.O. Box 669Carlin, NV 89822USATel. 1.775.778.4842Fax: 1.775.778.4038E-mail: [email protected]
Richard GoldfarbU.S. Geological SurveyBox 25046, MS 964Denver Federal Center Denver, CO 80225 –0046USATel. 1.303.236.2441Fax: 1.303.236.3200E-mail: [email protected]
Eliseo Gonzalez-UrienPlacer Dome Exploration 240 South Rock Blvd, Suite 117 Reno, NV 89502USATel. 1.775.856.2552Fax: 1.775.856.3091
David Groves Centre for Global MetallogenyDepartment of Geology and Geophysics
University of Western AustraliaNedlands, WA 6907AustraliaTel. 61.8.9380.2685Fax: 61.8.9380.1178E-mail: [email protected]
Steffen G. HagemannThe University of Western AustraliaDepartment of Geology and Geophysics
Centre for Global MetallogenyNedlands, WA 6907AustraliaTel. 61.8.9380.1517Fax: 61.8.9380.1178E-mail: [email protected]
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The Authors:
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Jeffrey W. Hedenquist99 Fifth Ave, Suite 420 Ottawa, Ontario K1S 5P5CanadaTel. 1.613.230.9191Fax: 1.613.230.9292E-mail: [email protected]
Albert H. HofstraU.S. Geological Survey Denver Federal Center Box 25046, MS 973Denver, CO 80225USATel. 1.303.236.5530Fax: 1.303.236.1829E-mail: [email protected]
J.M.A. HronskyWMC Resources Ltd. Exploration Division PO Box 91Belmont, WA 6984AustraliaTel. 61.08.9479.8400Fax: 61.08.9479.8451E-mail: [email protected]
David L. HustonAustralian Geological Survey Organisation
GPO Box 378Canberra, ACT. 2601AustraliaTel. 61.2.6249.9577Fax: 61.2.6249.9983E-mail: [email protected]
Eric P. Jensen Center for Mineral ResourcesDepartment of Geosciences University of ArizonaTucson, AZ 85721USATel. 1.520.626.4962Fax: 1.520.621.2672E-mail: [email protected]
Robert KerrichDepartment of Geological SciencesUniversity of SaskatchewanSaskatoon, Saskatchewan S7N 5E2CanadaTel. 1.306.966.5719Fax: 1.306.966.8593E-mail: [email protected]
Jonathan D.M. LawPO Box 147South Melbourne, Victoria 3205AustraliaTel. 27.11.376.2319Fax: 27.11.376.3658E-mail: [email protected]
T.C. McCuaigSRK Consulting25 Richardson StreetWest Perth, WA 6005AustraliaTel. 61.8.9322.2993Fax: 61.8.9322.2994E-mail: [email protected]
Lawrence D. MeinertDepartment of GeologyWashington State UniversityPullman, WA 99164-2812USATel. 1.509.335.2261Fax: 1.509.335.7816E-mail: [email protected]
Rainer J. NewberryDepartment of Geology University of Alaska-FairbanksFairbanks, AK 99775USATel. 1.907.474.6895Fax: 1.907.474.5163E-mail: [email protected]
Greg A. PartingtonInstitute of Geological and Nuclear Sciences Ltd.
PO Box 30 368Lower Hutt, WellingtonNew ZealandTel. 04.570.4795Fax: 04.570.4600E-mail: [email protected]
G. Neil PhillipsPO Box 3 Central Park, Victoria 3145AustraliaTel. 61.3.9234.1111Fax: 61.3.9234.1333E-mail: [email protected]
John R. Ridley GEMOCDepartment of Earth and Planetary Sciences
Macquarie UniversityNew South Wales 2109AustraliaTel. 61.2.9850.8371Fax: 61.2.9850.8943E-mail: [email protected]
Richard H. Sillitoe27 West Hill Park Highgate VillageLondon N6 6NDEnglandTel. 44.20.8340.9948Fax: 44.20.8342.8306
Stuart F. Simmons Geothermal Institute and Geology Department
University of AucklandPrivate Bag, 92019AucklandNew ZealandTel. 64.9.373.7599 Ext. 8710Fax: 64.9.373.7436E-mail: [email protected]
John F.H. Thompson Teck Corporation600-200 Burrard St. Vancouver, B.C. V6C 3L9CanadaTel. 1.604.687.1117Fax: 1.604.640.5381E-mail: [email protected]
Patrick J. WilliamsEconomic Geology Research UnitJames Cook UniversityTownsville, Queensland 4811AustraliaTel. 61.747.815223Fax: 61.747.251501E-mail: [email protected]
ANTONIO ARRIBAS ROSADO started research in eco-nomic geology at the University of Salamanca, Spain, with athesis on the origin of strata-bound W mineralization inPaleozoic sedimentary rocks of the Iberian peninsula.Between 1983 and 1985 he developed an interest in elec-tron microbeam and X-ray techniques to enable these toolsto be used routinely and efficiently for numerous theses andcollaborative projects with industry. Following two years asassistant professor at the University of Salamanca, he movedto the United States on a United States-Spain Joint Com-mittee Fulbright fellowship and begun Ph.D. work at theUniversity of Michigan, Ann Arbor, on the geology and geo-chemistry of the Rodalquilar high-sulfidation epithermaldeposit. From Michigan, he moved in 1992 to the Geologi-cal Survey of Japan in Tsukuba to investigate active volcanic-hydrothermal systems and the genetic relationship betweenporphyry and epithermal deposits. In 1996 he joined PlacerDome Exploration, Inc., as Senior Geologist with the Long-term Generative Group. At present he is Assistant to theVice-President of Exploration and Corporate Developmentand a member of the in-house Technical Services Groupwith responsibilities to aid in the generation and evaluationof epithermal projects worldwide.
MARK D. BARTON is professor of geology and Director ofthe Center for Mineral Resources at the University of Ari-zona (B.S., M.S., Virginia Polytechnic Institute and StateUniversity, 1977, 1978; Ph.D., University of Chicago, 1981).He was previously on the faculty at the University of Cali-fornia, Los Angeles, before moving to Arizona in 1990. Hisresearch interests broadly deal with understanding energyand mass transfer in the Earth’s lithosphere and applica-tions to natural resources. Current research focuses onmagmatic evolution and links with hydrothermal systems,the role of surficial conditions in mass transfer systems, andregional and global assessment of mineralizing systemsthrough time. Regional studies have centered on south-western North America in the context of the Pacific Rim.Porphyry, skarn, Fe oxide(-REE-Cu-Au) and other igneous-related systems remain the focus of deposit studies. In1991, he was given the Mineralogical Society of AmericaAward, and in 1992, the Society of Economic GeologistsLindgren Award. He was one of the two SEG InternationalExchange Lecturers for 1999.
FRANK P. BIERLEIN obtained an M.Sc. degree in geologyfrom the University of Heidelberg in 1991 and completeda Ph.D. on aspects of base metal, gold, and PGE mineral-ization in the Willyama inliers in South Australia at the Uni-versity of Melbourne in 1996. In the same year, he joinedthe Australian Minerals Industry Research Institute at theUniversity of Ballarat as a postdoctoral research fellow andbecame involved in studying the genesis of gold and VHMSmineralization in Victoria, with particular emphasis onaspects of timing and wall-rock alteration. He has sincebeen involved in numerous petrological, geochemical and
isotopic investigations dealing with slate belt-hosted goldmineralization in southeast Australia, New Zealand, andCanada. He is currently holder of a Logan Post-DoctoralFellowship in the Victorian Institute of Earth and PlanetarySciences at Monash University.
PHILIP E. BROWN has a B.A. degree from Carleton Col-lege (1974) and M.S. (1976) and Ph.D. (1980) degrees ineconomic geology from the University of Michigan. He hastaught at the University of Wisconsin-Madison since 1981,where he is professor of economic geology and teaches arange of undergraduate and graduate classes. He hasundertaken research projects on several continents and hasfocused on fluid inclusions and Archean gold deposits forthe past 13 years. Present interests include FTIR analysis ofgeologic samples, applications of technology to improvingteaching and distance education, and the development of3-D computer graphics to aid students in grasping thegeography and geometry of the world around them.
KEVIN F. CASSIDY completed a Ph.D. degree at the Uni-versity of Western Australia in 1992, focusing on Archeangranitoid-hosted lode gold deposits in the Yilgarn craton,Western Australia. From 1992 to 1995, he undertook post-doctoral work at the University of Saskatchewan on thetemporal relationship of lode gold deposits to magmatism,metamorphism, and deformation, and on the geochemicaland isotopic characteristics of alkalic intrusions associatedwith gold-rich porphyry systems in the Canadian Cordillera,the latter in conjunction with researchers at the MineralDeposit Research Unit, University of British Columbia.Since 1995, he has been with the Australian Geological Sur-vey Organisation, Canberra. His work has focused on devel-oping a detailed geologic and metallogenic framework ofthe Yilgarn craton, as well as on continuing research intolode gold mineralizing systems. Most of his work hasinvolved collaborative projects with university and industrypartners, principally through the Australian MineralsIndustry Research Institute. He is currently Project Leaderfor AGSO projects in the Yilgarn craton.
JEAN S. CLINE is currently an associate professor at theUniversity of Nevada, Las Vegas. After receiving a B.Sc.degree from the University of Wisconsin-Platteville, Clinespent 10 years exploring for base and precious metals, pri-marily in the western United States, for Inspiration Devel-opment Company. A casualty of the downturn in the min-ing industry during the 1980s, Cline returned to schooland earned an M.Sc. degree from the University of Arizonain 1986, and a Ph.D. degree from Virginia PolytechnicInstitute and State University in 1990. Upon graduation,Cline joined the faculty at UNLV. Current research isfocused on combining field studies, petrographic work, lab-oratory analyses, and numerical modeling to elucidate thegeochemical evolution and development of hydrothermalsystems.
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BIOGRAPHIES
DAVID R. COOKE completed a B.Sc. (hons.) degree atLatrobe University in 1985, prior to undertaking Ph.D. stud-ies at Monash University, where he investigated relationshipsbetween low-sulfidation epithermal gold and porphyrycopper-gold mineralization in the Philippines. Since 1991,he has worked at the University of Tasmania, investigatingthe geology and geochemistry of hydrothermal systems, withemphasis on porphyry, epithermal, and sedex styles of min-eralization. He is currently a senior lecturer in hydrothermalgeochemistry, and is the leader of Program 5 (hydrology andchemistry of hydrothermal systems) at the Centre for OreDeposit Research.
DOUG CROWE is an associate professor of geology at theUniversity of Georgia. He worked for Anaconda Mineralsand Cominco Alaska Exploration before assuming his cur-rent position at Georgia. He received his B.S. degree fromColgate University and his Ph.D. degree from the Univer-sity of Wisconsin-Madison. His research interests includethe geology and geochemistry of VHMS, skarn, andepithermal systems. He has advised students on a broadrange of industry-funded projects including work in Alaska,Nevada, Colorado, and Russia, as well as work on modernsea-floor hydrothermal environments. He currently directsthe University of Georgia stable isotope facility.
LARRY W. DIAMOND is professor of mineralogy andpetrology at the Institute of Geological Sciences, Universityof Leoben, Austria. He conducted his doctoral research atETH-Zürich on hydrothermal gold deposits, and continuedwork on this topic at posts in Ottawa and Bern. His maininterests are in the genesis of hydrothermal ore deposits,fluid-rock interaction, fluid phase relations, and the sys-tematics and applications of fluid inclusion studies.
POUL EMSBO received his B.S. degree in biology andchemistry from Union College. He received his M.S. andPh.D. degrees in geology from the Colorado School ofMines. His master’s research contributed to the under-standing the stratigraphy and metallogeny of the “upperplate” Vinini and Valmy Formation in Nevada. His disser-tation research focused on the genesis of the Meikle high-grade Carlin-type gold deposit and the geology and stratig-raphy of the northern Carlin trend. While at CSM he alsoworked at the U.S. Geological Survey, where he helpeddevelop a new method for analysis of electrolytes in fluidinclusions, established methods for the analysis of cyanidespecies, conducted research on basin fluid chemistry inMississippi Valley-type and sedex deposits, and studied Carlin-type deposits under the Western Gold Project. Currently,Emsbo is employed by the U.S. Geological Survey, investi-gating a possible link between sedex Au and Carlin-typemineralization on the Carlin trend and leading a new pro-ject on the chemistry of basin fluids.
STEVEN GARWIN obtained a B.S. degree in geology fromStanford University in 1984 and an M.Sc., geological sci-ences, University of British Columbia in 1987. Steve hasbeen a candidate for a Ph.D. degree in economic geologyat the University of Western Australia from 1998 to present.The title of his doctoral study, which is currently underreview, is The setting, geometry and timing of intrusion-relatedhydrothermal systems in the vicinity of the Batu Hijau porphyrycopper-gold deposit, Sumbawa, Indonesia. Garwin has 12 yearsexperience as an exploration geologist in Southeast Asia(1987–1999). He has worked in several countries, includingIndonesia, Philippines, Thailand, Laos, Malaysia, Myan-mar, China, Vietnam, and Papua New Guinea. During thepast seven years, he has been employed as a senior geolo-gist for Newmont Mining Corporation. In September 1999,Garwin joined Newmont’s Nevada operations in the role ofa consulting (regional) geologist.
RICHARD GOLDFARB has been a research geologist inthe Minerals Program of the U.S. Geological Survey in Den-ver for the past 20 years. During that time, he has been veryinvolved with the Survey's mineral resource assessment pro-gram in Alaska, including serving as the coordinator of geo-chemical exploration activities in Alaska for many years. Herecently authored parts and edited Economic GeologyMonograph 9, Mineral Deposits of Alaska. Goldfarb’s mainresearch interests include global gold metallogeny, with anemphasis on the temporal/spatial distribution of deposits;the geology of ore deposits in the North AmericanCordillera, with emphasis on orogenic gold and collisionaltectonics; and the relationship of fluid inclusion/stable iso-tope applications to the understanding of ore genesis.Goldfarb is also chief editor of Mineralium Deposita, adjunctprofessor in the Department of Geology at the University ofColorado, and active collaborator at the Centre for Teach-ing and Research in Strategic Mineral Deposits at Universityof Western Australia.
ELISEO GONZALEZ-URIEN represents the complex andmultifaceted world of metals exploration by large corpora-tions. Gonzalez-Urien, a citizen of the United States andSpain, obtained obtained a B.A. degree in geology from theUniversity of Chile, Santiago, in 1967. He later completedgraduate course work at the University of California at Berke-ley and the University of Colorado, prior to an unbrokenstring of exploration assignments worldwide. He has beenU.S. Exploration Manager for Noranda Minerals, Explo-ration Manager for BHP-Utah, and for the past 10 years, wasPresident and CEO of the exploration division of PlacerDome, Inc. He is now a senior advisor to Placer Dome.
DAVID GROVES earned a Ph.D. degree from the Univer-sity of Tasmania. He holds a Personal Chair in EconomicGeology at the University of Western Australia and is Direc-tor of the Centre for Strategic Mineral Deposits in theDepartment of Geology and Geophysics at UWA. He has
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BIOGRAPHIES (continued)
published widely on gold deposits, with special emphasison orogenic gold deposits, particularly Precambrian exam-ples. His major interests are in the development of inte-grated models for their genesis and the application ofthese models in computer-based prospectivity analysis anddevolopment of exploration targets.
STEFFEN G. HAGEMANN received his M.Sc. degree fromthe University of Wisconsin-Milwaukee and Madison in1989. His thesis dealt with gold mineralization in thethinned-skinned thrust Brasilia fold belt in central Brazil.In 1993, he obtained his Ph.D. degree from the Key Centrefor Strategic Mineral Deposits, University of Western Aus-tralia, with a project on the structural and hydrothermalcontrol of the Archean epizonal Wiluna lode gold deposits.After holding a postdoctoral position at the University ofWisconsin-Madison, with brief stints at the University ofToronto and the University of Saskatchewan, he took aposition as assistant professor at the Technical University ofMunich in 1996. Currently he is a senior lecturer in eco-nomic geology at the Centre for Strategic Mineral Deposits,University of Western Australia. His work has focused onthe structure and hydrothermal fluid chemistry of Archeanorogenic lode-gold deposits. Recently his research grouphas started projects on felsic intrusion-hosted gold miner-alization, hydrothermal fluid chemistry of ancient VHMSsystems, the role of structure and hydrothermal fluids inthe enrichment of Fe in BIF-hosted iron ore deposits, andthe 4-D connectivity between first, second, and higherorder fault zones and associated gold mineralization.
JEFFREY W. HEDENQUIST first worked on a gold depositin Montana while a student at The Johns Hopkins Univer-sity. The Au-bearing Archean chemical sediments of thedeposit, then thought to have formed by an exhalativeprocess, led him to the hot springs of New Zealand in 1979,supported by a Fulbright fellowship. There he studied thepresent-day deposition of gold in the Waiotapu geothermalsystem, and applied his results to the study of epithermalgold deposits. Following completion of a Ph.D. thesis at theUniversity of Auckland, he spent six years with the DSIRChemistry Division at the Wairakei field laboratory, wherehe conducted research related to the assessment and devel-opment of geothermal systems for their energy. Duringthis time he also was a consultant to governments andindustry involved with geothermal and epithermal explo-ration in the circum-Pacific. In 1989 he joined the Geolog-ical Survey of Japan, becoming the first non-Japanese to beemployed permanently within Japan's national institutes.His research focused on the characteristics and metal con-tent of volcanic discharges. At the same time he instigatedstudies on epithermal and porphyry deposits in the Philip-pines and Chile, and the relationship between these oretypes. He resigned at the end of 1998 in order to resumeconsulting, and now works worldwide on a variety ofepithermal and related projects, assessing prospects and
providing training for industry, while continuing researchon hydrothermal processes. He is based in Ottawa, Canada.
ALBERT H. HOFSTRA is a research geologist at the U.S.Geological Survey in Denver, where he has made importantcontributions to genetic models for Carlin-type golddeposits, mesothermal Ag-Pb-Zn veins, and Mississippi Val-ley-type Pb-Zn deposits. Hofstra also has developed tech-niques for the chemical analysis of fluid inclusions andapplication of these data to studies of ore deposits. HisPh.D. work at the University of Colorado, Boulder, was onthe geology and genesis of the Carlin-type gold deposits inthe Jerritt Canyon district. He has since been involved indetailed studies of Carlin-type deposits in the Carlin trend,Getchell trend, and Alligator Ridge district and pluton-related gold deposits in the Bald Mountain district. Hispublications on Carlin-type deposits address topics such astheir geochronology and relation to tectonics, mineral par-agenesis, alteration, lithogeochemistry, P-T-X and source ofore fluids, chemical modeling of ore formation, and envi-ronmental aspects of mining and mineral processing.
JON M.A. HRONSKY works with WMC Resources-Explo-ration Division as Exploration Manager-Project Genera-tion. In this role, he has global accountability for the early,conceptual stages of WMC’s project generation activitiesfor all ore types and he also maintains a role as WMC tech-nical specialist in the genesis of NiS deposits. Hronsky hasa particular interest in the generic aspects of targeting forgiant mineral deposits, in particular the influence of lithos-pheric architecture and geodynamic setting. He gradu-ated from the University of Western Australia school ofmines in Kalgoorlie in 1983 and subsequently completed aPh.D. degree at UWA in 1993. His Ph.D work was on theLancefield gold deposit in the northeastern gold fields ofWestern Australia.
DAVID HUSTON has undertaken research into the geologyand geochemistry of volcanic-hosted massive sulfide depositsfrom a large variety of terranes and ages over the past 15years. As part of this research he documented the spatial andmineralogical distributions of gold in VHMS deposits inPaleozoic volcanic belts in eastern Australia, and developedgeochemical models to describe the metallogenesis of goldVHMS deposits in general. He has also researched otheraspects of VHMS mineralization, including isotope geo-chemistry, alteration geochemistry, hydrothermal geochem-istry, and ore mineralogy. Other interests include Fe oxide-hosted Cu-Au deposits, lode Au deposits, low-sulfidationepithermal deposits, high-sulfidation Cu-Au deposits, andArchean metallogeny. He is presently working on the metal-logenesis of the Pilbara craton.
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BIOGRAPHIES (continued)
ERIC JENSEN received a B.A. degree in geology in 1993from Carlton College, and worked as a “paraprof” in thegeology department at Colorado College from 1993 to 1994.After studying economic geology at Stanford University in1994–1995, he worked as a mine geologist and explorationgeologist for the Cripple Creek and Victor Gold MiningCompany. He is currently completing his Ph.D. degree at theUniversity of Arizona. His present research is focused on thepetrology, geochemistry, and styles of mineralization associ-ated with alkaline magmatism, and he works part-time forAnglogold North America at their operations in CrippleCreek, Colorado.
ROB KERRICH graduated from Imperial College with aPh.D. degree, then pursued postdoctoral studies at the Uni-versity of Western Ontario, advised by Bill Fyfe, and at theCalifornia Institute of Technology. Since then he has taughtgeology, first at the University of Western Ontario, andsince 1986, he has been at the University of Saskatchewan.Kerrich has established stable isotope, fluid inclusion, andICP-MS labs, and has applied these analytical techniques toa variety of questions in earth sciences. His interests aregeoepidemiology, metallic mineral resources, geodynamics,fluid-rock interaction, and plume geochemistry.
JONATHAN D.M. LAW graduated from the University ofthe Witwatersrand in 1991 with an M.Sc degree, focusingon alteration and mineralization in the Welkom gold fieldof the Witwatersrand basin. Subsequently, he worked in theWitwatersrand exploration and mining industry for 10years. In the early 1990s, the Gencor group undertook amajor research project to evaluate the regional geologicframework of the Witwatersrand basin. Law was the coor-dinator of the program on alteration and mineralization,and the regional scope of this work provided the opportu-nity to link data sets from many mines around the basinwith mapping, seismic studies, and exploration databases.Ongoing work with Neil Phillips led to the development ofthe hydrothermal replacement model for the mineraliza-tion. He has subsequently been involved in the evaluationof various geologic terranes, and specifically, the explo-ration potential of sedimentary basins.
CAM McCUAIG is a Senior Associate with SRK Consultingbased in Perth, Western Australia, and is Geology Manager-Western Australia. He obtained his B.Sc. (hons.) degreefrom Lakehead University, Ontario, and his Ph.D. degreefrom the University of Saskatchewan. His Ph.D. thesisaddressed the genesis of orogenic gold deposits. JoiningEtheridge Henley Williams as a consultant in 1995,McCuaig has remained with the company through itsmerger with SRK Consulting. His role largely consists oftranslating academic research on ore deposits into practicalapplications in industry. With more than 12 years experi-ence in understanding ore deposits, McCuaig has beeninvited to speak and provide short courses at many inter-
national conferences, and to provide training to industryclients on aspects of structural geology, hydrothermal alter-ation, orebody genesis and practical applications of geologyto the exploration and mining industry. His internationalexperience includes gold projects in Australia, Africa, Asia,Europe, North America, and South America, ranging fromArchean through Proterozoic to Phanerozoic in age.
LAWRENCE D. MEINERT received a B.A. degree in geol-ogy from Carleton College and a Ph.D. degree from Stan-ford University in 1980. Currently, he is professor of eco-nomic geology at Washington State University, where hisresearch is focused on high-temperature metasomatism inthe magmatic-hydrothermal environment and the petroge-nesis of plutons associated with ore deposits. He is author orco-author of several widely cited review articles on skarndeposits as well as numerous studies of individual skarns. Inaddition to purely academic research, he works extensivelywith private industry and government agencies in morethan 30 countries on projects ranging from grass-rootsexploration to mine development. His basic approach isstrongly field oriented with mapping and drill core loggingforming the observational base for deriving genetic models.He has direct field experience with many of the majorskarn deposits in the world.
RAINER NEWBERRY received B.S. degrees in chemistryand in geology from Massachusetts Institute of Technology(M.I.T) in 1975, and M.S. (1978) and Ph.D. (1980) degreesin geology from Stanford University. He has taught at theUniversity of Alaska since 1982, where he is professor ofeconomic geology; he teaches a wide range of undergrad-uate and graduate classes. Newberry works with the U.S.Geological Survey and Alaska State Survey in regional- anddeposit-scale mapping in Alaska and follow-up analyticalstudies. He and his graduate students have studied a widevariety of deposits in Alaska, including skarn, VMS, sedex,orogenic vein, greisen, porphyry, magmatic, and reducedintrusion-related deposits.
GREG PARTINGTON is currently the General ManagerExploration for Ross Mining N.L., responsible for manag-ing all exploration at all the company mine sites in Aus-tralia and the Pacific. He received a Ph.D. degree from theUniversity of Western Australia, where he still holds an hon-orary associate research position. He has worked for severalmining and exploration companies in Northern Australiaand has experience in exploration for gold, tin, tantalum,and platinum. During this time, he has been involved inresearch on structural controls on Archean and Protero-zoic gold mineralization and mineralization related to peg-matites and granites. He has published more than 30papers related to this research. Other interests include theuse of GIS and prospectivity modeling in exploration.
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BIOGRAPHIES (continued)
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G. NEIL PHILLIPS is a graduate of Melbourne Universityand Monash University and has dual experience in acade-mia and the exploration industry. He joined the staff of theUniversity of the Witwatersrand in 1985; while there he ledresearch projects on all operating gold mines. His researchhas been supported by the major Witwatersrand miningcompanies and the Chamber of Mines of South Africa,which has meant virtually unrivalled access across the basin.This work has led to a fundamental reassessment of post-depositional processes in the Witwatersrand basin and tothe development of the hydrothermal replacement modelfor the mineralization. His experience in Archean green-stone and slate belt gold provinces has been a key contrib-utor to unraveling the postdepositional history of the Wit-watersrand. More recently, Phillips has been inauguralProfessor of Economic Geology in Townsville and Directorof the National Key Centre In Economic Geology. He iscurrently working with Jonathan Law in the Australianexploration industry to combine the new Witwatersrandgenetic model with a global assessment of sedimentarybasins to evaluate the potential for “Witwatersrand-style”mineralization.
JOHN R. RIDLEY is lecturer in ore deposit geology, geo-chemistry, and metamorphic geology at the Department ofEarth and Planetary Sciences, Macquarie University, Aus-tralia. He received a Ph.D. degree from Edinburgh Uni-versity for work on structural and metamorphic geology,and has subsequently worked in Switzerland, Norway, Zim-babwe, and Australia. His recent research work has been onthe genesis of hydrothermal ore deposits, in particulargold deposits, and on more general questions of hydrother-mal fluid flow in the crust.
RICHARD H. SILLITOE graduated from the University ofLondon, England, where he went on to obtain a Ph.D.degree in economic geology in 1968. After spending timewith the Geological Survey of Chile, he has worked for thelast 30 years as an independent consultant for mining com-panies, international agencies, and foreign governments.Assignments have involved a wide variety of base and pre-cious metal deposits and prospects in 75 countries world-
wide, with specialization in the porphyry copper andepithermal gold environments. He was president of SEGfor the year 1999–2000.
STUART F. SIMMONS earned a B.A. degree in geologyfrom Macalester College (1978), and M.S. (1982) andPh.D. (1986) degrees in economic geology from the Uni-versity of Minnesota. He completed postdoctoral researchin the Geology Department, University of Auckland(1987–1990) and was appointed to an academic teachingposition in the Geothermal Institute (1991), where he iscurrently a senior lecturer in geothermal geochemistry.His research focuses on the formation of epithermaldeposits and evolution of active geothermal systems.
JOHN THOMPSON received his a B.A. degree fromOxford University (1976) and M.Sc. (1978) and Ph.D.(1982) degrees from the University of Toronto. He workedin mineral exploration for 10 years, based in Australia, Eng-land, and the United States, and was involved in projectsand area selection worldwide. From 1991 until 1998, he wasDirector of the Mineral Deposit Research Unit at the Uni-versity of British Columbia, where he developed and man-aged collaborative research projects with the mining andexploration industry. He moved to his present position asChief Geoscientist, Teck Corporation, in early 1998.
PATRICK J. WILLIAMS is a senior lecturer in economicgeology at James Cook University in Queensland, Australia.He received the degrees of B.Sc. (hons.) and Ph.D., respec-tively, from the University of Liverpool (1978) and theUniversity of Southampton (1982). He taught economicgeology at Goldsmiths College, University of London,before joining James Cook University in 1990. His primaryresearch interests have centered on the metallogeny ofbase metals and gold in metamorphic belts. In recentyears, this has involved a focus on Fe oxide copper-gold andBroken Hill-type lead-zinc-silver deposits in Australian Pro-terozoic terrains. Other current work involves studies ofintrusion-related copper-gold deposits in West Papua andPeru, and the development of microbeam methods forfluid inclusion analysis.
BIOGRAPHIES (continued)
Gold in 2000—An IntroductionSteffen G. Hagemann and Philip E. Brown
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Chapter 1—Archean Orogenic Lode Gold Deposits Steffen G. Hagemann and
Kevin F. CassidyAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Archean Orogenic Lode Gold Mineral Systems . . . .11Case Studies of Representative Archean Orogenic Lode Gold Deposits . . . . . . . . . . . . . . . . .15
Synthesis of Archean Orogenic Lode Gold System Characteristics . . . . . . . . . . . . . . . . . . . . . . . .34
Open Questions and Future Work . . . . . . . . . . . . . . .59Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . .60References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Chapter 2—Proterozoic Lode Gold and (Iron)-Copper-Gold Deposits: A Comparison of Australian and Global Examples
Greg A. Partington and Patrick J. WilliamsAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Australian Proterozoic Lode Gold Deposits . . . . . . .71Other Proterozoic Lode Gold Deposits . . . . . . . . . . .83Australian Cu-Au-Fe Deposits . . . . . . . . . . . . . . . . . . .86Other (Fe)-Cu-Au Deposits . . . . . . . . . . . . . . . . . . . . .90Genetic Models: A Discussion . . . . . . . . . . . . . . . . . . .92Conclusions and Implications for Future Exploration . . . . . . . . . . . . . . . . . . . . . . . . . .95
Open Questions and Future Work . . . . . . . . . . . . . . .96Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . .97References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
Chapter 3—Phanerozoic Orogenic Lode Gold Deposits
Frank P. Bierlein and Douglas E. CroweAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Geotectonic Controls . . . . . . . . . . . . . . . . . . . . . . . . .105Geologic Setting and Host-Rock Lithology . . . . . . .106Metamorphism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Structural Controls on Mineralization . . . . . . . . . . .114Morphology of Deposits . . . . . . . . . . . . . . . . . . . . . .115Physico-Chemical Characteristics of Lode Gold Mineralization . . . . . . . . . . . . . . . . . . . .117
Timing of Mineralization . . . . . . . . . . . . . . . . . . . . .124Carolina Slate Belt—A Cautionary Tale . . . . . . . . . .125Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Implications for Exploration, Open Questions, and Future Work . . . . . . . . . . . . . . . . . .129
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .131
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Questions and Answers . . . . . . . . . . . . . . . . . . . . . . .136Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137
Chapter 4—Fluid Chemistry of Orogenic Lode Gold Deposits and Implications for Genetic Models
John R. Ridley and Larryn W. DiamondAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Overview of the Nature of Orogenic Lode Gold Deposits . . . . . . . . . . . . . . . . . . . . . . . . .141
Fluid Chemistry at the Deposits . . . . . . . . . . . . . . . .144Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .157References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Questions and Answers . . . . . . . . . . . . . . . . . . . . . . .162
Chapter 5—Characteristics and Models for Carlin-Type Gold Deposits
Albert H. Hofstra and Jean S. ClineAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164Age of Carlin-Type Deposits . . . . . . . . . . . . . . . . . . .169Tectonic History . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Ore Controls-Controls on Fluid Movement . . . . . . .175Deposit and District Parameters . . . . . . . . . . . . . . . .176Alteration and Mineral Paragenesis . . . . . . . . . . . . .178Lithogeochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . .190Organic Carbon . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194Fluid Inclusion Studies . . . . . . . . . . . . . . . . . . . . . . .195Depth of Formation . . . . . . . . . . . . . . . . . . . . . . . . . .202Sources of Ore Fluid Components . . . . . . . . . . . . . .203Mass-Balance Constraints on the Size of the Hydrothermal Systems . . . . . . . . . . . . . . . . .210
Discussion of Models for Carlin-Type Gold Deposits . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210
Open Questions and Future Work . . . . . . . . . . . . . .213Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .214References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214
Chapter 6—Characteristics and Genesis of Epithermal Gold Deposits
David R. Cooke and Stuart F. SimmonsAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Tectonic-Volcanic Settings, Space-Time Relationships, and Orebodies . . . . . . . . . . . . . . . . .223
Low Sulfidation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226High Sulfidation . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Epithermal Mineralization in Modern Environments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232
Chemical Environments of Ore Deposition . . . . . .235Deposition Processes . . . . . . . . . . . . . . . . . . . . . . . . .237Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .241References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241
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CONTENTS
Chapter 7—Exploration for Epithermal Gold Deposits
Jeffrey W. Hedenquist, Antonio Arribas R., and Eliseo Gonzalez-Urien
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .245Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Exploration Philosophy . . . . . . . . . . . . . . . . . . . . . . .246Nature of the Epithermal Environment . . . . . . . . .247Genetic Framework . . . . . . . . . . . . . . . . . . . . . . . . . .253Setting and General Characteristics of Epithermal Ore Deposits . . . . . . . . . . . . . . . . . . . .258
Exploration of Epithermal Prospects: Relevant Observations and Useful Tools . . . . . . . .265
Giant Epithermal Gold Deposits: Are There Fundamental Controls? . . . . . . . . . . . .273
Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . .274Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .274References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .274Questions and Answers . . . . . . . . . . . . . . . . . . . . . . .277
Chapter 8—Gold Deposits Related to Alkaline Magmatism
Eric P. Jensen and Mark D. BartonAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .279Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .279Epithermal-Style Deposits . . . . . . . . . . . . . . . . . . . . .284Transition between Epithermal and Porphyry Deposits . . . . . . . . . . . . . . . . . . . . . . . . . .297
Porphyry-Type Deposits . . . . . . . . . . . . . . . . . . . . . . .297Summary of Characteristics . . . . . . . . . . . . . . . . . . .301Constraints on Genesis . . . . . . . . . . . . . . . . . . . . . . .302Tectonics and Petrogenesis . . . . . . . . . . . . . . . . . . . .306Other Types of Gold Deposits Linked to Alkaline Magmatism . . . . . . . . . . . . . . . . . . . . . .307
Alkaline Rock Types not Associated with Gold Mineralization . . . . . . . . . . . . . . . . . . . .308
Exploration Considerations . . . . . . . . . . . . . . . . . . .308Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .310References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .310
Chapter 9—Gold-Rich Porphyry Deposits: Descriptive and Genetic Models and Their Role in Exploration and Discovery
Richard H. SillitoeAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .315Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .315Descriptive Model . . . . . . . . . . . . . . . . . . . . . . . . . . .316Genetic Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .326Exploration and Discovery . . . . . . . . . . . . . . . . . . . .333Some Outstanding Questions . . . . . . . . . . . . . . . . . .338Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .340References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .340Questions and Answers . . . . . . . . . . . . . . . . . . . . . . .344
Chapter 10—Gold in Skarns Related to Epizonal Intrusions
Lawrence D. MeinertAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .347Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .347Au Skarns Associated with Reduced Magmatic-Hydrothermal Systems . . . . . . . . . . . . . .349
Oxidized Magmatic-Hydrothermal Systems . . . . . . .362Summary and Conclusions . . . . . . . . . . . . . . . . . . . .371References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .372
Chapter 11—Gold Deposits Related to Reduced Granitic Intrusions
John F. H. Thompson and Rainer J. NewberryAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .377Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .377General Characteristics of Reduced Intrusion-Related Gold Deposits . . . . . . . . . . . . . .378
Characteristics of Individual Belts and Districts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .385
Genesis of Intrusion-Related Gold Deposits . . . . . .392Questions and Future Research . . . . . . . . . . . . . . . .395Exploration for Intrusion-Related Gold Deposits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .396
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .397References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .397
Chapter 12—Gold in Volcanic-Hosted Massive Sulfide Deposits: Distribution, Genesis, and Exploration
David L. HustonAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .401Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .401Characteristics of Gold in Volcanic-Hosted Massive Sulfide Deposits . . . . . . . . . . . . . .408
Examples of Gold-Rich Volcanic-Hosted Massive Sulfide Deposits . . . . . . . . . . . . . . . . . . . . .410
Regional Controls on Gold Grades and Metallogenesis in Volcanic-Hosted Massive Sulfide Deposits . . . . . . . . . . . . . . . . . . . . .415
Atypical Gold Mineralization in Volcanic-Hosted Massive Sulfide Deposits . . . . . . .415
Geochemical Models for the Deposition of Gold in Volcanic-Hosted Massive Sulfide Deposits . . . . . . . . . . . . . . . . . . . . . . . . . . . .416
The Sources and Transport of Gold . . . . . . . . . . . . .419Exploration Criteria for Gold-Rich Deposits in the Volcanic-Hosted Massive Sulfide Mineral System . . . . . . . . . . . . . . .419
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .421Open Questions and Directions for Future Research . . . . . . . . . . . . . . . . . . . . . . . . . . . .422
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .423References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .423Questions and Answers . . . . . . . . . . . . . . . . . . . . . . .426
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Chapter 13—Gold in Sedex DepositsPoul Emsbo
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .427Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .427Sedex versus Volcanic-Hosted Massive Sulfide Deposits . . . . . . . . . . . . . . . . . . . . . . . . . . . .427
Spectrum of Sedex Deposits . . . . . . . . . . . . . . . . . . .428Gold in Sedex Zn-Pb-Ba ± Au Deposits . . . . . . . . . .428Nevada Sedex Au Occurrences . . . . . . . . . . . . . . . . .430Fluid Chemistry and Controls on Metal Solubility . . . . . . . . . . . . . . . . . . . . . . . . . . . .431
Generation of H2S-Rich Brines . . . . . . . . . . . . . . . . .433Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .433Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .436Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .436References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .436
Chapter 14—Witwatersrand Gold Fields: Geology, Genesis, and Exploration
G. Neil Phillips and Jonathon D. M. LawAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .439Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .440Regional Geologic Framework . . . . . . . . . . . . . . . . .441The Gold Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . .454Genesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .488 Exploration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .494Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .495References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .495
Chapter 15—The Geodynamics of World-Class Gold Deposits: Characteristics, Space-Time Distribution, and Origins
Robert Kerrich, Richard Goldfarb, David Groves, and Steven Garwin
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .501
Introduction and Scope . . . . . . . . . . . . . . . . . . . . . .502Mineral Deposits, Geodynamic Settings, and the Supercontinent Cycle . . . . . . . . . . . . . . . .503
Orogenic Gold Deposits . . . . . . . . . . . . . . . . . . . . . .507Carlin and Carlin-Like Gold Deposits . . . . . . . . . . .514Arc-Related Epithermal Gold Deposits . . . . . . . . . .519Copper-Gold Porphyry Deposits . . . . . . . . . . . . . . . .524Iron Oxide Cu-Au Deposits . . . . . . . . . . . . . . . . . . . .529Gold-Rich Volcanic-Hosted Massive Sulfide and Sedex Deposits . . . . . . . . . . . . . . . . . .532
Geodynamics of World-Class Gold Deposits: Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . .537Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .544References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .544
Chapter 16—The Current Status and Future of the Interface between the Exploration Industry and Economic Geology Research
T. C. McCuaig and J. M. A. HronskyAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .553Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .553The Exploration Process and the Role of Conceptual Geology . . . . . . . . . . . . . . . . . .554
Misalignment between the Requirements of Industry and the Products of Academia . . . . . . . . . . . . . . . . . . . . . . .556
The Root Causes of Industry-Academia Misalignment . . . . . . . . . . . . . . . . . . . . .557
A Vision for Economic Geology Research in the New Millennium . . . . . . . . . . . . . . . . . . . . . .558
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . .559