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The Mining Industries, 1899-1939: A Study of Output, Employment, and Productivity [PDF]
Harold Barger, Sam H. Schurr
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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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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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The Sar Cheshmeh porphyry copper deposit
Economic Geology, 1975The Sar Cheshmeh porphyry copper, located in southern Iran, was mined in ancient times, "rediscovered" about 1966, explored during 1966-1969, and will be in full production in 1977 at a rate of 40,000 tons of ore per day. Mineralization is associated with a late Tertiary granodiorite porphyry stock, cut by a series of genetically related intramineral ...
G. C. Waterman, R. L. Hamilton
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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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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 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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Marcopper porphyry copper deposit, Philippines
Economic Geology, 1976Marcopper porphyry copper deposit is located in the Philippines near the center of the island of Marinduque, 180 km south of Manila. The island9s tectonic history is dominated by northwesterly trending elements of the Philippine mobile belt. Mineralization is related to differentiated intermediate intrusives which occupy the core of a northwesterly ...
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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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Magmatic sources of copper in porphyry copper deposits
Economic Geology, 1978During crystallization of a granitic magma, copper is shown to prefer octahedral sites, be they in the melt or in crystalline phases. Burns and Fyfe (1964) showed that the Al 2 O 3 /(K 2 O + Na 2 O + CaO) ratio of the magma is proportional to the number of octahedral sites available in the melt.
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