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Tourmaline as a Tracer of Late-Magmatic to Hydrothermal Fluid Evolution: The World-Class San Rafael Tin (-Copper) Deposit, Peru Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Matthieu Harlaux, Kalin Kouzmanov, Stefano Gialli, Oscar Laurent, Andrea Rielli, Andrea Dini, Alain Chauvet, Andrew Menzies, Miroslav Kalinaj, Lluís Fontboté
The world-class San Rafael tin (-copper) deposit (central Andean tin belt, southeast Peru) is an exceptionally large and rich (>1 million metric tons Sn; grades typically >2% Sn) cassiterite-bearing hydrothermal vein system hosted by a late Oligocene (ca. 24 Ma) peraluminous K-feldspar-megacrystic granitic complex and surrounding Ordovician shales affected by deformation and low-grade metamorphism
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The Occurrence and Origin of Pentlandite-Chalcopyrite-Pyrrhotite Loop Textures in Magmatic Ni-Cu Sulfide Ores Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Stephen J. Barnes, Valentina Taranovic, Louise E. Schoneveld, Eduardo T. Mansur, Margaux Le Vaillant, Sarah Dare, Sebastian Staude, Noreen J. Evans, Daryl Blanks
Pentlandite is the dominant Ni-hosting ore mineral in most magmatic sulfide deposits and has conventionally been interpreted as being entirely generated by solid-state exsolution from the high-temperature monosulfide solid solution (MSS) (Fe,Ni)1–xS. This process gives rise to the development of loops of pentlandite surrounding pyrrhotite grains. Recently it has been recognized that not all pentlandite
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Sulfide Emplacement and Migration in the Nova-Bollinger Ni-Cu-Co Deposit, Albany-Fraser Orogen, Western Australia Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Stephen J. Barnes, Valentina Taranovic, John M. Miller, Glenn Boyce, Steve Beresford
The Nova-Bollinger Ni-Cu sulfide deposit is associated with a small chonolith (tube-shaped) intrusion emplaced at lower crustal depths into granulite facies migmatite gneisses. The deposit comprises disseminated and net-textured ores within the intrusions and a high proportion of massive, semimassive, and breccia exocontact ores within the underlying country rocks. Internally disposed endocontact ores
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Origin of Tin Mineralization in the Sullivan Pb-Zn-Ag Deposit, British Columbia: Constraints from Textures, Geochemistry, and LA-ICP-MS U-Pb Geochronology of Cassiterite Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 John F. Slack, Leonid A. Neymark, Richard J. Moscati, Heather A. Lowers, Paul W. Ransom, Robert L. Hauser, David T. Adams
Textural, geochronological, and geochemical data are presented here for cassiterite from the giant (149.7 million tonnes [Mt]) Mesoproterozoic Sullivan Pb-Zn-Ag deposit, which has been subjected to several tectonothermal events. These data provide constraints on the age and origin of the tin concentrations and new insights into related base metal mineralization. Sullivan is rare among sediment-hosted
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OPENING THE MAGMATIC-HYDROTHERMAL WINDOW: HIGH-PRECISION U-Pb GEOCHRONOLOGY OF THE MESOPROTEROZOIC OLYMPIC DAM Cu-U-Au-Ag DEPOSIT, SOUTH AUSTRALIA Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Liam Courtney-Davies, Cristiana L. Ciobanu, Simon R. Tapster, Nigel J. Cook, Kathy Ehrig, James L. Crowley, Max R. Verdugo-Ihl, Benjamin P. Wade, Daniel J. Condon
Establishing timescales for iron oxide copper-gold (IOCG) deposit formation and the temporal relationships between ores and the magmatic rocks from which hydrothermal, metal-rich fluids are sourced is often dependent on low-precision data, particularly for deposits that formed during the Proterozoic. Unlike accessory minerals routinely used to track hydrothermal mineralization, iron oxides are dominant
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UPGRADING OF MAGMATIC SULFIDES, REVISITED Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 James E. Mungall, M. Christopher Jenkins, Samuel J. Robb, Zhuosen Yao, James M. Brenan
There has been vigorous debate for several decades about whether the extreme enrichments of platinum group elements (PGEs) in some magmatic sulfide deposits could have resulted from simple equilibration of sulfide liquid with silicate melt. Key examples include the Ni-Cu-Pd mineralization in the Norilsk mining camp, the UG2 and Merensky reef Pt-Pd deposits in the Bushveld Complex, the Pd-rich J-M reef
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U-Pb DATING OF HYDROTHERMAL TITANITE RESOLVES MULTIPLE PHASES OF PROPYLITIC ALTERATION IN THE OYU TOLGOI PORPHYRY DISTRICT, MONGOLIA Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Lisa Hart-Madigan, Jamie J. Wilkinson, Stephanie Lasalle, Robin N. Armstrong
Oyu Tolgoi is a world-class, Late Devonian porphyry district in southern Mongolia. Because of its age and geodynamic setting, it has undergone a complex geological history that includes major postmineralization magmatic-hydrothermal events in close proximity to the porphyry deposits. The propylitic alteration halos that surround the Cu-Au deposits contain widespread hydrothermal titanite, as do the
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Genesis of As-Pb-Rich Supergene Mineralization: The Tazalaght and Agoujgal Cu Deposits (Moroccan Anti-Atlas Copperbelt) Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Michèle Verhaert, Atman Madi, Abdelaziz El Basbas, Mohamed Elharkaty, Abdellah Oummouch, Lahcen Oumohou, Annelies Malfliet, Lhou Maacha, Johan Yans
In the Moroccan Anti-Atlas, sulfide deposits hosted by Neoproterozoic to Cambrian formations underwent significant weathering, leading to the formation of supergene profiles. In the Tazalaght Cu-As deposit, three mineralogical steps are distinguished: (1) the replacement of hypogene sulfides (chalcopyrite, pyrite, tennantite) by supergene sulfides (bornite, chalcocite) in the large cementation zone;
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The Nature and Composition of the J-M Reef, Stillwater Complex, Montana, USA Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 M. Christopher Jenkins, James E. Mungall, Michael L. Zientek, Paul Holick, Kevin Butak
In this contribution, we analyze 30 years of mine development data and quantitatively identify the processes that control the grade and tenor of the mineralized rock. An assay database of more than 60,000 samples was used to examine variations in ore grade and tenor of the sulfide mineralization in the J-M reef horizon of the Stillwater Complex along the strike and down the dip of the deposit in the
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PLATINUM-BEARING PLACERS: MINERAL ASSOCIATIONS AND THEIR 190 Pt- 4 He AND Re-Os AGES, AND POTENTIAL LINKS WITH LARGE IGNEOUS PROVINCES IN THE SIBERIAN CRATON Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 A. V. Okrugin, O. V. Yakubovich, R. E. Ernst, Zh.Yu. Druzhinina
Placer deposits in the Siberian platform are closely associated with well-known platiniferous intrusions (Kondyor, Inagli, Noril’sk, Chiney, and Guli) but there are also abundant platinum-group mineral (PGM) placers of large areal extent in the river basins of Siberia (Vilyui, Lena, Aldan, Anabar, and Olenek) for which the primary sources are unknown. The 190Pt-4He dating method is introduced, compared
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Analysis of a Telescoped Orogenic Gold System: Insights from the Fosterville Deposit Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Christopher R. Voisey, Andrew G. Tomkins, Yanlu Xing
The Fosterville gold (Au) deposit is hosted in the Bendigo zone within the western Lachlan orogen, southeast Australia, and contains three distinct mineralization styles: (1) refractory Au in fine-grained arsenopyrite and arsenian pyrite disseminated throughout metasedimentary rocks near brittle faults, (2) visible Au hosted in fault-controlled quartz-carbonate veins associated with stibnite mineralization
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Occurrence and Distribution of Silver in the World-Class Río Blanco Porphyry Cu-Mo Deposit, Central Chile Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Jorge Crespo, Martin Reich, Fernando Barra, Juan José Verdugo, Claudio Martínez, Mathieu Leisen, Rurik Romero, Diego Morata, Carlos Marquardt
Porphyry Cu-Mo deposits (PCDs) are the world’s major source of Cu, Mo, and Re and are also a significant source of Au and Ag. Here we focus on the world-class Río Blanco PCD in the Andes of central Chile, where Ag is a by-product of Cu mining. Statistical examination of an extensive multielemental inductively coupled plasma-mass spectrometry data set indicates compositional trends at the deposit scale
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Rare Earth Element Resources: Indian Context Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Philip L. Verplanck
Rare Earth Element Resources: Indian Context. Yamuna Singh. 2020. ISBN 978-3-030-41353-8. Society of Earth Scientists Series, Springer, Cham, Switzerland, 269 Pp. Hardcover and eBook. €93.08Rare Earth Element Resources: Indian Context by Yamuna Singh provides an excellent review of rare earth element (REE) deposits and occurrences in India with an emphasis on placer deposits, India’s most notable REE
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AN EXPERIMENTAL STUDY OF THE SOLUBILITY AND SPECIATION OF MoO 3 (s) IN HYDROTHERMAL FLUIDS AT TEMPERATURES UP TO 350°C—A REPLY Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Linbo Shang, A.E. Williams-Jones, Xinsong Wang, A. Timofeev, Ruizhong Hu, Xianwu Bi
To the Editor: In our paper entitled “An Experimental Study of the Solubility and Speciation of MoO3(s) in Hydrothermal Fluids at Temperatures up to 350°C,” we reported results of a study designed to determine the solubility of MoO3(s) in NaCl-bearing aqueous fluids at elevated temperature. We did so in order to gain insights into the manner in which Mo is transported in the saline fluids that form
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AN EXPERIMENTAL STUDY OF THE SOLUBILITY AND SPECIATION OF MoO 3 (s) IN HYDROTHERMAL FLUIDS AT TEMPERATURES UP TO 350°C—A DISCUSSION Econ. Geol. (IF 4.013) Pub Date : 2020-12-01 Andrey V. Plyasunov
To the Editor: This journal has recently published a study on solubility of molybdenum trioxide, MoO3, in aqueous solutions (water, sodium chloride, or triflate) at 250°, 300°, and 350°C, and vapor-saturated water pressure (Shang et al., 2020). The authors have found that the MoO3 solubility is minimal in water and starts increasing at the molality of NaCl above 0.01 m. Surprisingly, the authors made
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ERRATUM Econ. Geol. (IF 4.013) Pub Date : 2020-12-01
In the paper, “Triple Oxygen (δ18O, Δ17O), Hydrogen (δ2H), and Iron (δ56Fe) Stable Isotope Signatures Indicate a Silicate Magma Source and Magmatic-Hydrothermal Genesis for Magnetite Orebodies at El Laco, Chile,” by Tristan Childress, Adam C. Simon, Martin Reich, Fernando Barra, Laura D. Bilenker, Nikita L. La Cruz, Ilya N. Bindeman, and J. Tomás Ovalle (Vol. 115, issue 7, 2020, p. 1529, Fig. 8), an
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Re-Os PYRITE GEOCHRONOLOGY OF THE YELLOWHEAD-TYPE MINERALIZATION, PEND OREILLE MINE, KOOTENAY ARC, METALINE DISTRICT, WASHINGTON Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 Suzanne Paradis, Danny Hnatyshin, George J. Simandl, Robert A. Creaser
Pend Oreille, a carbonate-hosted Zn-Pb sulfide deposit, is the only base metal mine recently in production within the historically prolific Kootenay arc belt. The deposit consists of two spatially and lithologically distinct types of stratabound, carbonate-hosted Zn-Pb mineralization: Josephine and Yellowhead. The Yellowhead-type sulfide mineralization, the focus of this study, consists of en échelon
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ARSENIC-INDUCED DOWNSHIFT OF RAMAN BAND POSITIONS FOR PYRITE Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 Qiaoqiao Zhu, Nigel J. Cook, Guiqing Xie, Benjamin P. Wade, Cristiana L. Ciobanu
Pyrite commonly incorporates a wide range of trace and minor elements, which in turn may modify some of the mineral’s physical and chemical properties. Published band position data for the Raman spectra of pyrite show a wide variation, and the relationship between band position and the trace/minor element incorporation in pyrite is poorly constrained until now. This prompted a case study on pyrite
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Geochemical and Isotopic Signature of Pyrite as a Proxy for Fluid Source and Evolution in the Candelaria-Punta del Cobre Iron Oxide Copper-Gold District, Chile Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 I. del Real, J.F.H. Thompson, A. C. Simon, M. Reich
Pyrite is ubiquitous in the world-class iron oxide copper-gold (IOCG) deposits of the Candelaria-Punta del Cobre district, documented from early to late stages of mineralization and observed in deep and shallow levels of mineralized bodies. Despite its abundance, the chemical and isotopic signature of pyrite from the Candelaria-Punta del Cobre district, and most IOCG deposits worldwide, remains poorly
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Metals Are Where You Find Them: Geologist’s Travels Through Six Continents (Peter Laznicka) Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 Douglas J. Kirwin
Metals Are Where You Find Them: Geologist’s Travels Through Six Continents. Peter Laznicka. 2019. 528 pages, 106 MB PDF file. Available online from http://payhip.com/MetallogenicaAdelaide. US$52. 50% student discount available.The author has published several widely acclaimed technical books about global ore deposits and their genesis. This volume is a compilation of his personal travel experiences
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A Continuum from Iron Oxide Copper-Gold to Iron Oxide-Apatite Deposits: Evidence from Fe and O Stable Isotopes and Trace Element Chemistry of Magnetite Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 Maria A. Rodriguez-Mustafa, Adam C. Simon, Irene del Real, John F.H. Thompson, Laura D. Bilenker, Fernando Barra, Ilya Bindeman, David Cadwell
Iron oxide copper-gold (IOCG) and iron oxide-apatite (IOA) deposits are major sources of Fe, Cu, and Au. Magnetite is the modally dominant and commodity mineral in IOA deposits, whereas magnetite and hematite are predominant in IOCG deposits, with copper sulfides being the primary commodity minerals. It is generally accepted that IOCG deposits formed by hydrothermal processes, but there is a lack of
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Triple Oxygen ( δ 18 O, Δ 17 O), Hydrogen ( δ 2 H), and Iron ( δ 56 Fe) Stable Isotope Signatures Indicate a Silicate Magma Source and Magmatic-Hydrothermal Genesis for Magnetite Orebodies at El Laco, Chile Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 Tristan Childress, Adam C. Simon, Martin Reich, Fernando Barra, Laura D. Bilenker, Nikita L. La Cruz, Ilya N. Bindeman, J. Tomás Ovalle
The Plio-Pleistocene El Laco iron oxide-apatite (IOA) orebodies in northern Chile are some of the most enigmatic mineral deposits on Earth, interpreted to have formed as lava flows or by hydrothermal replacement, two radically different processes. Field observations provide some support for both processes, but ultimately fail to explain all observations. Previously proposed genetic models based on
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Petrography and Geochemistry of the Carboniferous Ortokarnash Manganese Deposit in the Western Kunlun Mountains, Xinjiang Province, China: Implications for the Depositional Environment and the Origin of Mineralization Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 Bang-Lu Zhang, Chang-Le Wang, Leslie J. Robbins, Lian-Chang Zhang, Kurt O. Konhauser, Zhi-Guo Dong, Wen-Jun Li, Zi-Dong Peng, Meng-Tian Zheng
The Upper Carboniferous Ortokarnash manganese ore deposit in the West Kunlun orogenic belt of the Xinjiang province in China is hosted in the Kalaatehe Formation. The latter is composed of three members: (1) the 1st Member is a volcanic breccia limestone, (2) the 2nd Member is a sandy limestone, and (3) the 3rd Member is a dark gray to black marlstone containing the manganese carbonate mineralization
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Stable C, O, and S Isotope Record of Magmatic-Hydrothermal Interactions Between the Falémé Fe Skarn and the Loulo Au Systems in Western Mali Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 James S. Lambert-Smith, Andrew Allibone, Peter J. Treloar, David M. Lawrence, Adrian J. Boyce, Mark Fanning
The Gara, Yalea, and Gounkoto Au deposits of the >17 Moz Loulo mining district, largely hosted by the Kofi series metasediments, are located several kilometers to the east of the 650-Mt Fe skarn deposits in the adjacent Falémé batholith. The Au deposits are interpreted to have formed through phase separation of an aqueous-carbonic fluid, which locally mixed with a hypersaline brine of metaevaporite
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The Geochemistry of Magnetite and Apatite from the El Laco Iron Oxide-Apatite Deposit, Chile: Implications for Ore Genesis Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 Nikita L. La Cruz, J. Tomás Ovalle, Adam C. Simon, Brian A. Konecke, Fernando Barra, Martin Reich, Mathieu Leisen, Tristan M. Childress
The textures of outcrop and near-surface exposures of the massive magnetite orebodies (>90 vol % magnetite) at the Plio-Pleistocene El Laco iron oxide-apatite (IOA) deposit in northern Chile are similar to basaltic lava flows and have compositions that overlap high- and low-temperature hydrothermal magnetite. Existing models—liquid immiscibility and complete metasomatic replacement of andesitic lava
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Carmacks Copper Cu-Au-Ag Deposit: Mineralization and Postore Migmatization of a Stikine Arc Porphyry Copper System in Yukon, Canada Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 Nikolett Kovacs, Murray M. Allan, James L. Crowley, Maurice Colpron, Craig J.R. Hart, Alex Zagorevski, Robert A. Creaser
Late Triassic to Early Jurassic porphyry Cu mineralization is common in British Columbia, yet there are few age-equivalent porphyry occurrences in Yukon. This study presents new data for the enigmatic Carmacks Copper Cu-Au-Ag deposit in south-central Yukon, Canada, which is hosted in amphibolite facies metamorphic inliers within the Early Jurassic Granite Mountain batholith. Sulfide mineralization
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The Onto Cu-Au Discovery, Eastern Sumbawa, Indonesia: A Large, Middle Pleistocene Lithocap-Hosted High-Sulfidation Covellite-Pyrite Porphyry Deposit Econ. Geol. (IF 4.013) Pub Date : 2020-11-01 David R. Burrows, Michael Rennison, David Burt, Rod Davies
In 2013, a diamond drill program tested an extensive advanced argillic alteration lithocap within the Hu’u project on eastern Sumbawa Island, Indonesia. A very large and blind copper-gold deposit (Onto) was discovered, in which copper occurs largely as disseminated covellite with pyrite, and as pyrite-covellite veinlets in a tabular block measuring at least 1.5 × 1 km, with a vertical thickness of
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Oxygen-Hafnium-Neodymium Isotope Constraints on the Origin of the Talnakh Ultramafic-Mafic Intrusion (Norilsk Province, Russia) Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Kreshimir N. Malitch, Elena A. Belousova, William L. Griffin, Laure Martin, Inna Yu. Badanina, Sergey F. Sluzhenikin
The ultramafic-mafic Talnakh intrusion in the Norilsk province (Russia) hosts one of the world’s major platinum group element (PGE)-Cu-Ni sulfide deposits. This study employed a multitechnique approach, including in situ Hf-O isotope analyses of zircon combined with whole-rock Nd isotope data, in order to gain new insights into genesis of the Talnakh economic intrusion. Zircons from gabbrodiorite,
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Correlation of the Permian-Triassic Ore-Bearing Intrusions of the Norilsk Region with the Volcanic Sequence of the Siberian Traps Based on the Paleomagnetic Data Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 A. V. Latyshev, V. A. Rad’ko, R. V. Veselovskiy, A. M. Fetisova, V. E. Pavlov
We present detailed paleomagnetic data from the Permian-Triassic Cu-Ni-Pt–bearing intrusions of the Norilsk region (northwestern Siberian platform). Based on the analysis of geomagnetic secular variations recorded in the intrusions, we correlate the Norilsk ore-bearing intrusions with the Siberian Traps volcanic sequences in the region. The similarity of paleomagnetic directions of the ore-bearing
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Platinum Group Element Enrichment of Natural Quenched Sulfide Solid Solutions, the Norilsk 1 Deposit, Russia Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Valeriya D. Brovchenko, Sergey F. Sluzhenikin, Elena V. Kovalchuk, Sofia V. Kovrigina, Vera D. Abramova, Marina A. Yudovskaya
The deepest terminations of the Mount Rudnaya subvertical massive sulfide offshoots of the Norilsk 1 orebody are composed of exceptionally fine grained sulfides that are believed to be natural quenched sulfide solid solutions. Copper-rich intermediate solid solution (ISS) and Fe-rich monosulfide solid solution (MSS) form an equigranular and lamellar matrix hosting MSS- and ISS-dominant globules. The
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Silicate and Oxide Mineral Chemistry and Textures of the Norilsk-Talnakh Ni-Cu-Platinum Group Element Ore-Bearing Intrusions Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Louise Schoneveld, Stephen J. Barnes, Morgan Williams, Margaux Le Vaillant, David Paterson
A large proportion of the disseminated sulfide ores of the Norilsk-Talnakh camp are hosted within olivine-rich, ultramafic cumulate layers called picro-gabbrodolerite units. In this study we quantitatively analyze the chemistry and textures of the silicate and oxide minerals within olivine-bearing cumulates of the Kharaelakh, Norilsk 1, and Talnakh intrusions to determine how these intrusions compare
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Oxide-Sulfide-Melt-Bubble Interactions in Spinel-Rich Taxitic Rocks of the Norilsk-Talnakh Intrusions, Polar Siberia Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Louise Schoneveld, Stephen J. Barnes, Belinda Godel, Margaux Le Vaillant, Marina A. Yudovskaya, Vadim Kamenetsky, Sergey F. Sluzhenikin
Oxide-rimmed, spherical structures interpreted as former gas bubbles have been discovered within a chromitiferous taxitic lithology of the Norilsk-Talnakh intrusions. These rocks are represented by variable grain size, presence of reworked country-rock xenoliths and millimeter- to centimeter-scale irregular spinel-rich aggregates, patches, or disrupted seams and stringers. They contain spherical and
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Hybrid Nature of the Platinum Group Element Chromite-Rich Rocks of the Norilsk 1 Intrusion: Genetic Constraints from Cr Spinel and Spinel-Hosted Multiphase Inclusions Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Ivan F. Chayka, Vadim S. Kamenetsky, Liudmila M. Zhitova, Andrey E. Izokh, Nadezhda D. Tolstykh, Adam Abersteiner, Boris M. Lobastov, Tamara Yu. Yakich
The Norilsk 1 intrusion (Russia), renowned for its abundance of sulfide ores, contains an upper contact zone, which hosts sulfide-poor and Cr spinel and platinum group element (PGE)-rich discontinuous reefs with significant economic potential. Located within strongly inhomogeneous contact rocks of various compositions, the origin of these reefs is complex and debated. Enrichment in PGEs in these rocks
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Magnetite Chemistry by LA-ICP-MS Records Sulfide Fractional Crystallization in Massive Nickel-Copper-Platinum Group Element Ores from the Norilsk-Talnakh Mining District (Siberia, Russia): Implications for Trace Element Partitioning into Magnetite Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Charley J. Duran, Sarah-Jane Barnes, Eduardo T. Mansur, Sarah A.S. Dare, L. Paul Bédard, Sergey F. Sluzhenikin
Mineralogical and chemical zonations observed in massive sulfide ores from Ni-Cu-platinum group element (PGE) deposits are commonly ascribed to the fractional crystallization of monosulfide solid solution (MSS) and intermediate solid solution (ISS) from sulfide liquid. Recent studies of classic examples of zoned orebodies at Sudbury and Voisey’s Bay (Canada) demonstrated that the chemistry of magnetite
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Low-Sulfide Platinum Group Element Ores of the Norilsk-Talnakh Camp Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Sergey F. Sluzhenikin, Marina A. Yudovskaya, Stephen J. Barnes, Vera D. Abramova, Margaux Le Vaillant, Dmitry B. Petrenko, Antonina V. Grigor’eva, Valeriya D. Brovchenko
Low-sulfide platinum group element (PGE) mineralization of the Norilsk-type intrusions is located within the Upper Gabbroic Series, which comprises rocks heterogeneous in texture and composition. The highest grade of 10 to 50 g/t PGEs is confined primarily to chromitiferous taxitic gabbrodolerite, which forms irregular lens- and vein-like bodies that interfinger with contact gabbrodolerite, intrusion
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Contact Metamorphic and Metasomatic Processes at the Kharaelakh Intrusion, Oktyabrsk Deposit, Norilsk-Talnakh Ore District: Application of LA-ICP-MS Dating of Perovskite, Apatite, Garnet, and Titanite Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Alexander E. Marfin, Alexei V. Ivanov, Vadim S. Kamenetsky, Adam Abersteiner, Tamara Yu. Yakich, Timur V. Dudkin
The Norilsk-Talnakh ore district in the northwestern Siberian platform contains globally unique reserves of Cu-Ni-sulfides with Pt and, especially, Pd. The Oktyabrsk deposit, which is one of the largest in the district, is spatially and genetically associated with the Kharaelakh mafic-ultramafic intrusion and its exceptionally large metamorphic and metasomatic aureoles. In this study, we employed in
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ERRATA Econ. Geol. (IF 4.013) Pub Date : 2020-09-01
In the paper, “The dynamic sulfide saturation process and a possible slab break-off model for the giant Xiarihamu magmatic nickel ore deposit in the East Kunlun orogenic belt, northern Qinghai-Tibet Plateau, China,” by YueGao Liu, WenYuan Li, QunZi Jia, ZhaoWei Zhang, ZhiAn Wang, ZhiBing Zhang, JiangWei Zhang, and Bing Qian (Volume 113, no. 6, p. 1383–1417), references to Chen et al. (2009) and Tian
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Introduction to a Special Issue on the Norilsk-Talnakh Ni-Cu-Platinum Group Element Deposits Econ. Geol. (IF 4.013) Pub Date : 2020-09-01 Stephen J. Barnes, Kreshimir N. Malitch, Marina A. Yudovskaya
The Ni-Cu-platinum group element (PGE) deposits of the Norilsk-Talnakh district in Arctic Siberia are among the most valuable metal accumulations of any kind on Earth. Not only are they extraordinary ore deposits, but they are also an integral part of one of the most cataclysmic events in the history of the planet, the Siberian large igneous province, linked to arguably the most influential event in
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A NEW SUBSEAFLOOR REPLACEMENT MODEL FOR THE MACMILLAN PASS CLASTIC-DOMINANT Zn-Pb ± Ba DEPOSITS (YUKON, CANADA) Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Joseph M. Magnall, Sarah A. Gleeson, Suzanne Paradis
Sedimentary exhalative (SEDEX) deposits are a subset of sediment-hosted massive sulfide deposits and provide our dominant resource of Zn. In the SEDEX model, base metals (Zn, Pb, Fe) are hydrothermally vented into sulfidic (euxinic) seawater and deposited coevally with the organic-rich mudstone host rock, resulting in laterally extensive layered mineralization. In the Selwyn Basin (Canada) at Macmillan
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Protracted Magmatism and Mineralized Hydrothermal Activity at the Gibraltar Porphyry Copper-Molybdenum Deposit, British Columbia Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Christopher Kobylinski, Keiko Hattori, Scott Smith, Alain Plouffe
The Gibraltar Cu-Mo deposit, with a total tonnage of 3.2 million tons (Mt) Cu, is located in the Canadian Cordillera and hosted by the Late Triassic Granite Mountain batholith. The batholith formed through multiple intrusions of tonalitic rocks over a period of ~25 m.y. beginning at 229.2 ± 4.4 Ma in the Quesnel island arc before the accretion of the arc to the North American continent. Late in its
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Sulfur Isotope Constraints on the Conditions of Pyrite Formation in the Paleoproterozoic Urquhart Shale Formation and George Fisher Zn-Pb-Ag Deposit, Northern Australia Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Philip Rieger, Joseph M. Magnall, Sarah A. Gleeson, Richard Lilly, Alexander Rocholl, Christof Kusebauch
The Carpentaria province (McArthur basin and Mount Isa inlier) in northern Australia is one of the most important districts for clastic-dominated (CD-type) massive sulfide deposits. The George Fisher Zn-Pb-Ag deposit, located in this province, is hosted by the carbonaceous Urquhart Shale Formation (ca. 1654 Ma) in a region that has an active history of metamorphism and tectonism. In this study, paragenetically
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Controls on the Dynamics of Rare Earth Elements During Subtropical Hillslope Processes and Formation of Regolith-Hosted Deposits Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Martin Yan Hei Li, Mei-Fu Zhou, Anthony E. Williams-Jones
Subtropical weathering of granitic catchments in South China has led to the formation of numerous giant regolith-hosted rare earth element (REE) deposits that currently account for more than 15% of global REE production and more than 95% of global heavy REE (HREE) production. Understanding the controls on mobilization and redistribution of the REEs during subtropical weathering in these granitic catchments
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The Mineralogical Evolution of the Clastic Dominant-Type Zn-Pb ± Ba Deposits at Macmillan Pass (Yukon, Canada)—Tracing Subseafloor Barite Replacement in the Layered Mineralization Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Joseph M. Magnall, Sarah A. Gleeson, Robert A. Creaser, Suzanne Paradis, Johannes Glodny, J. Richard Kyle
Clastic dominant-type massive sulfide deposits are well preserved in Upper Devonian carbonaceous mudstones in the Macmillan Pass district (Yukon, Canada). The Macmillan Pass deposits have been considered to be type examples of sedimentary exhalative Zn-Pb mineralization, whereby sulfides precipitated when hydrothermal fluids were vented into a euxinic (H2S-bearing) water column. We propose a new mineralization
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Tracing Mineralogy and Alteration Intensity Using the Spectral Alteration Index and Depth Ratios at the Northwest Zone of the Lemarchant Volcanogenic Massive Sulfide Deposit, Newfoundland, Canada Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Jonathan Cloutier, Stephen J. Piercey
The use of hyperspectral reflectance in mineral exploration has been steadily increasing in recent decades. This study presents a novel approach that integrates geochemical and spectral proxies to delineate ore formation and alteration processes, which provide new spectral-based exploration parameters that can be used in real time. The precious metal-bearing, bimodal-felsic Northwest zone of the Lemarchant
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The Tectonics and Metallogenesis of Asia(Tianfeng Wan) Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Richard J. Goldfarb
The Tectonics and Metallogenesis of Asia. Tianfeng Wan. 2020. Springer. 319 Pp. eBook ISBN 978-981-15-3032-6. Hardcover ISBN 978-981-15-3031-9. €155.99.This is an ambitious volume that attempts to review the tectonic provinces of Asia, their geological history, and their metallogeny. The preface notes that the economic geology aspects of the volume are based on collected information from “242 giant
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ORE CLASSIFICATION OF PSEUDOBRECCIA ORE IN THE 144 ZONE GOLD DEPOSIT: A CHEMICAL REPLACEMENT MODEL, BARE MOUNTAIN RANGE, NEVADA Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Bill T. Fischer, Jean S. Cline
The 144 zone is a pseudobreccia-hosted, disseminated gold deposit that formed in the middle to late Cambrian Bonanza King dolostone along an unconformity with the underlying early to middle Cambrian Carrara limestone at Bare Mountain, southern Nevada. Underground mapping revealed spatial relationships between breccia types, host rocks, and alteration assemblages that are related to gold mineralization
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Lithium and Brine Geochemistry in the Salars of the Southern Puna, Andean Plateau of Argentina Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Romina Lucrecia López Steinmetz, Stefano Salvi, Carisa Sarchi, Carla Santamans, Lorena Cecilia López Steinmetz
The Andean plateau is a small region of South America extending between northwest Argentina, southwest Bolivia, and northern Chile. It concentrates the largest global resources of lithium brines in its numerous salars. Of these, the giant salars in Bolivia and Chile have been relatively well studied; however, only little is known about the smaller but numerous salars in the Argentine Puna region. In
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A Multistage Genetic Model for the Metamorphosed Mesoproterozoic Swartberg Base Metal Deposit, Aggeneys-Gamsberg Ore District, South Africa Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Tarryn Kim Cawood, Abraham Rozendaal
The polymetamorphosed Swartberg Cu-Pb-Zn-Ag deposit in the Namaqua Metamorphic Province of South Africa is a major metal producer in the region, yet its genesis remains poorly understood. The deposit comprises several stratiform to stratabound units, namely the Lower Orebody and Dark Quartzite, the overlying Barite Unit, and the Upper Orebody, all of which are folded by an F2 isoclinal syncline and
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New Mapping of the World-Class Jinding Zn-Pb Deposit, Lanping Basin, Southwest China: Genesis of Ore Host Rocks and Records of Hydrocarbon-Rock Interaction Econ. Geol. (IF 4.013) Pub Date : 2020-08-01 Yucai Song, Zengqian Hou, Chuandong Xue, Shiqiang Huang
Jinding is the third-largest known Mississippi Valley-type (MVT) Zn-Pb deposit. It is hosted by a dome containing a suite of complex breccias and sandstones with abundant gypsum and anhydrite. This study presents the results of new geologic mapping of the Jinding open pit and discusses the geology of the deposit in detail. Our new data support a previously proposed model where the deposit is hosted
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In Situ Elemental and Sr Isotope Characteristics of Magmatic to Hydrothermal Minerals from the Black Mountain Porphyry Deposit, Baguio District, Philippines Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 MingJian Cao, Pete Hollings, Noreen J. Evans, David R. Cooke, Brent I.A. McInnes, KuiDong Zhao, KeZhang Qin, DengFeng Li, Gabe Sweet
At the Black Mountain porphyry Cu-Au deposit in the Baguio district, Northern Luzon (Philippines), pre- and synmineralized rocks preserve magmatic and hydrothermal minerals (e.g., plagioclase, amphibole, titanite, and epidote) spanning the complete paragenesis of the deposit. Strontium isotope values in early crystallized plagioclase phenocrysts from all felsic porphyries can be divided into two types
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Chlorite and Epidote Mineral Chemistry in Porphyry Ore Systems: A Case Study of the Northparkes District, New South Wales, Australia Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Adam Pacey, Jamie J. Wilkinson, David R. Cooke
Propylitic alteration, characterized by the occurrence of chlorite and epidote, is typically the most extensive and peripheral alteration facies developed around porphyry ore deposits. However, exploration within this alteration domain is particularly challenging, commonly owing to weak or nonexistent whole-rock geochemical gradients and the fact that similar assemblages can be developed in other geologic
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A Microscale Analysis of Hydrothermal Epidote: Implications for the Use of Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry Mineral Chemistry in Complex Alteration Environments Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Ayesha D. Ahmed, Louise Fisher, Mark Pearce, Angela Escolme, David R. Cooke, Daryl Howard, Ivan Belousov
High-resolution, quantitative imaging of epidote from the Ann Mason fault block, Yerington district, Nevada, using scanning electron microscopy (SEM), X-ray fluorescence (XRF), and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) has revealed at least two types of epidote (type 1 and type 2), each with different major and trace element chemistry. Type 1 epidote is coarser grained
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Magmatic Fluids Implicated in the Formation of Propylitic Alteration: Oxygen, Hydrogen, and Strontium Isotope Constraints from the Northparkes Porphyry Cu-Au District, New South Wales, Australia Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Adam Pacey, Jamie J. Wilkinson, Adrian J. Boyce, Ian L. Millar
In porphyry ore deposit models, the propylitic alteration facies is widely interpreted to be caused by convective circulation of meteoric waters. However, recent field-based and geochemical data suggest that magmatic-derived fluids are likely to contribute to development of the propylitic assemblage. In order to test this hypothesis, we determined the oxygen and hydrogen isotope compositions of propylitic
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Using Mineral Chemistry to Aid Exploration: A Case Study from the Resolution Porphyry Cu-Mo Deposit, Arizona Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 David R. Cooke, Jamie J. Wilkinson, Mike Baker, Paul Agnew, Josh Phillips, Zhaoshan Chang, Huayong Chen, Clara C. Wilkinson, Shaun Inglis, Pete Hollings, Lejun Zhang, J. Bruce Gemmell, Noel C. White, Leonid Danyushevsky, Hamish Martin
The giant, high-grade Resolution porphyry Cu-Mo deposit in the Superior district of Arizona is hosted in Proterozoic and Paleozoic basement and in an overlying Cretaceous volcaniclastic breccia and sandstone package. Resolution has a central domain of potassic alteration that extends more than 1 km outboard of the ore zone, overlapping with a propylitic halo characterized by epidote, chlorite, and
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Linking Mineralogy to Lithogeochemistry in the Highland Valley Copper District: Implications for Porphyry Copper Footprints Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Kevin Byrne, Guillaume Lesage, Sarah A. Gleeson, Stephen J. Piercey, Philip Lypaczewski, Kurt Kyser
The Highland Valley Copper porphyry deposits, hosted in the Late Triassic Guichon Creek batholith in the Canadian Cordillera, are unusual in that some of them formed at depths of at least 4 to 5 km in cogenetic host rocks. Enrichments in ore and pathfinder elements are generally limited to a few hundred meters beyond the pit areas, and the peripheral alteration is restricted to narrow (1–3 cm) halos
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Exploring the Green Rock Environment: An Introduction Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Orovan Evan, Hollings Pete
Exploration for porphyry deposits in the past few decades has become increasingly expensive, with new discoveries often occurring at considerable depths or obscured through extensive postmineralization cover (Schodde, 2017; Cooke et al., 2020a). Given these complexities, new exploration techniques or novel applications of known techniques are needed to ensure continued discoveries into the future.
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Chemical Variations in Hydrothermal White Mica Across the Highland Valley Porphyry Cu-Mo District, British Columbia, Canada Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Tatiana Alva-Jimenez, Richard M. Tosdal, John H. Dilles, Gregory Dipple, Adam J.R. Kent, Scott Halley
Hydrothermal white mica in the Highland Valley district, British Columbia, is present in high-temperature alteration assemblages in early halo veins and in intermediate-temperature sericitic alteration assemblages in D-type veins. Pale-gray white micas characterize early halo veins in the Valley and Bethsaida zone porphyry Cu-Mo deposits, whereas pale-green white micas form texturally similar vein
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Exploration Targeting in Porphyry Cu Systems Using Propylitic Mineral Chemistry: A Case Study of the El Teniente Deposit, Chile Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Jamie J. Wilkinson, Michael J. Baker, David R. Cooke, Clara C. Wilkinson
The mineral chemistry of epidote and chlorite from the propylitic halo at El Teniente, in samples collected at distances up to 6.6 km from the deposit center, was determined by microprobe and laser ablation-inductively coupled plasma-mass spectrometry. Results show that both minerals systematically incorporated a range of trace elements that define a much larger footprint to the system than is easily
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Mineralogical and Isotopic Characteristics of Sodic-Calcic Alteration in the Highland Valley Copper District, British Columbia, Canada: Implications for Fluid Sources in Porphyry Cu Systems Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Kevin Byrne, Robert B. Trumbull, Guillaume Lesage, Sarah A. Gleeson, John Ryan, Kurt Kyser, Robert G. Lee
The Highland Valley Copper porphyry Cu (±Mo) district is hosted in the Late Triassic Guichon Creek batholith in the Canadian Cordillera. Fracture-controlled sodic-calcic alteration is important because it forms a large footprint (34 km2) outside of the porphyry Cu centers. This alteration consists of epidote ± actinolite ± tourmaline veins with halos of K-feldspar–destructive albite (1–20 XAn) ± fine-grained
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Epidote Trace Element Chemistry as an Exploration Tool in the Collahuasi District, Northern Chile Econ. Geol. (IF 4.013) Pub Date : 2020-06-01 Michael J. Baker, Jamie J. Wilkinson, Clara C. Wilkinson, David R. Cooke, Tim Ireland
The Collahuasi district of northern Chile hosts several late Eocene-early Oligocene world-class porphyry Cu-Mo deposits, including Rosario, Ujina, and Quebrada Blanca deposits, and associated high-sulfidation epithermal mineralization at La Grande. Mineralization is hosted by intermediate to felsic intrusive and volcanic rocks of the upper Paleozoic to Lower Triassic Collahuasi Group, which experienced
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