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Geological Society, London, Special Publications, 1977
Summary Porphyry copper deposits are large crustal sulphur anomalies containing copper and other metals. Much of the sulphur is oxidized and, along with a major portion of the copper, deposited from fluids evolved from certain calc-alkaline melts of intermediate composition.
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Summary Porphyry copper deposits are large crustal sulphur anomalies containing copper and other metals. Much of the sulphur is oxidized and, along with a major portion of the copper, deposited from fluids evolved from certain calc-alkaline melts of intermediate composition.
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The michiquillay porphyry copper deposit
Mineralium Deposita, 1974Michiquillay is a mineralized intrusive quartz monzonite porphyry displaying typical porphyry copper alteration zones as found in metallized intrusives of that composition. From the interior outward these are the phyllic, argillic and propylitic zones. The potassic zone is not exposed at the surface.
V.F. Hollister, E.B. Sirvas
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Origin of phenocrysts in mineralized porphyries of porphyry copper deposits
2005The genetic mechanism of phenocrysts in mineralized porphyries of the Yulong porphyry copper deposit, Tibet, China, has been studied in the context of fluid inclusions in quartz and K-feldspar phenocrysts, phenocryst textures and mineral crystal textures.
Wenming Chen, Jifu Sheng
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Porphyry Copper Deposit Density
Economic Geology, 2005Estimating numbers of undiscovered mineral deposits has been a source of unease among economic geologists yet is a fundamental task in considering future supplies of resources. Estimates can be based on frequencies of deposits per unit of permissive area in control areas around the world in the same way that grade and tonnage frequencies are models of ...
D. A. Singer +3 more
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Porphyry tin deposits in Bolivia
Economic Geology, 1975Tin production from the central and southern parts of the Bolivian tin province has been derived largely from lode systems associated with high-level, late Tertiary stocks of intermediate composition. This paper proposes that several of these stocks, including those at the major Llallagua, Potosi, Oruro, and Chorolque mineralized centers, geological ...
R. H. Sillitoe, C. Halls, J. N. Grant
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The formation of porphyry copper deposits
Acta Geochimica, 2016Copper is a moderately incompatible chalcophile element. Its behavior is strongly controlled by sulfides. The speciation of sulfur is controlled by oxygen fugacity. Therefore, porphyry Cu deposits are usually oxidized (with oxygen fugacities > ΔFMQ +2) (Mungall 2002; Sun et al. 2015).
Weidong Sun +8 more
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Porphyry–copper deposits of Bulgaria
International Geology Review, 1983(1983). Porphyry–copper deposits of Bulgaria. International Geology Review: Vol. 25, No. 2, pp. 178-188.
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Philippine Porphyry and Epithermal Deposits: An Introduction
Economic Geology, 2011The Philippines is one of the most richly endowed parts of the Southwest Pacific, with many porphyry copper-gold and epithermal gold-silver deposits scattered along the archipelago (e.g., Sillitoe and Gappe, 1984; Mitchell and Leach, 1991; Fig. 1). Chinese mining artifacts discovered in the Baguio and Masbate districts suggest that gold and silver ...
Cooke, David R +2 more
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Porphyry-Type Deposits of the Appalachian Orogen
Economic Geology, 1974Absolute age, change in metallogeny, alteration, zoning; Paleozoic, New England, Maritime ...
V. F. Hollister +2 more
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How to make porphyry copper deposits
Earth and Planetary Science Letters, 2020Abstract Much of the world's economic copper resources are hosted in porphyry copper deposits (PCDs), shallow level magmatic intrusions associated mostly with thick ( > 45 km ) magmatic arcs, such as mature island arcs and continental arcs. However, a well-known, but unresolved paradox, is that arc magmas traversing thick crust, particularly ...
Cin-Ty A. Lee, Ming Tang
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