Escondida

Porphyry copper (Cu-Au) deposit in Antofagasta, Chile

Names and other identifiers

GMRAP ID 297
Alternate names La Escondida
Tract name Chile Eocene–Oligocene Chuquicamata (005pCu1010)
Included sites Escondida Norte, Zaldivar
Site status deposit

Geographic location

Country Chile
State or province Antofagasta
Geographic location -69.071666667, -24.265
Geologic map unit -69.071666667, -24.265
Nearby data

Geologic information

Deposit type Porphyry copper
Deposit subtype Cu-Au
Age (Ma) 37Ma
Age determination method unknown
Age range 38.72 ±0.17 to 34.9 ±0.41 Ma
Age reference Singer and others (2008)
Minerals alunite, anhydrite/gypsum, anilite, antlerite, atacamite, biotite, bornite, brochantite, chalcocite, chalcopyrite, chlorite, chrysocolla, copper, covellite, cuprite, diaspore, digenite, djurleite, enargite, epidote, galena, goethite, hematite, idaite, jarosite, kaolinite, limonite, magnetite, marcasite, molybdenite, pyrite, pyrophyllite, sericite, sphalerite, svanbergite, tennantite, turquoise
Associated rocks breccia, granodiorite porphyry, quartz monzonite porphyry, rhyolite porphyry, skarn, andesite, conglomerate, diorite, granodiorite, limestone, sandstone
Tectonic setting continental margin
Stratigraphic age Eocene

Commodity and development information

Development status Producer
Major commodities Cu, Mo, Au, Ag
Minor commodities Pt, Pd
Tonnage (Mt) 11,158Mt
Cu grade (%) 0.769%
Mo grade (%) 0.0062%
Au grade (g/t) 0.25g/t
Ag grade (g/t) 5g/t
Contained copper 85,800,000t
Gold-Moly ratio 40

Reference information

Comments Cu enrichment age 18–15 Ma. In concentrate: 8 ppb Pt, 44 ppb Pd. 10% of the deposit area is covered by gravel.
Study area name Andes
References Alpers and Brimhall (1989); Briggs (2006); Campos and others (2002); Lowell (1991b); Ojeda (1986); Ortiz (1995); Ortiz and others (1995); Padilla Garza and others (2001); Porter (2005); Richards and others (2001); Sillitoe and McKee (1996); Tarkian and Stribrny (1999); Zappettini and others (2001); Singer and others (2008)
Site reference Cunningham and others (2008)
Alpers, C.N., and Brimhall, G.H., 1989, Paleohydrologic evolution and geochemical dynamics of cumulative supergene metal enrichment at La Escondida, Atacama Desert, northern Chile: Economic Geology, v. 84, p. 229–255. (Also available at http://dx.doi.org/10.2113/gsecongeo.84.2.229.)
Briggs, D.F., 2006, Mining operations report, ver. 2005: unpublished report, [unknown] p.
Campos, E., Touret, J.L.R., Nikogosian, I., and Delgado, J., 2002, Overheated, Cu-bearing magmas in the Zaldivar porphyry-Cu deposit, northern Chile—Geodynamic consequences: Tectonophysics, v. 345, p. 229–251. (Also available at http://ac.els-cdn.com/S0040195101002153/1-s2.0-S0040195101002153-main.pdf?_tid=bec92998-6809-11e3-8238-00000aab0f6b&acdnat=1387387861_1c6b78f4c497daa7b9116624a0d4a377.)
Lowell, J.D., 1991b, The discovery of the La Escondida orebody, in Hutchinson, R.V., and Grauch, R.I., eds., Historical perspectives of genetic concepts and case histories of famous discoveries: Economic Geology Monograph 8, p. 300–319.
Ojeda, F.J.M., 1986, Escondida porphyry copper deposit, II Region, Chile—Exploration drilling and current geological interpretation: London, Institution of Mining and Metallurgy, Mining Latin America, p. 299–318.
Ortiz, F.J., 1995, Discovery of the Escondida porphyry copper deposit in the Antofagasta region, in Pierce, F.W., and Bolm, J.G., eds., Porphyry copper deposits of the American Cordillera: Tucson, Arizona Geological Society Digest 20, p. 613–624.
Ortiz, F.J., Lowell, J.D., Bratt, J.A., Rojas, N.D. and Burns, P.J., 1995, Escondida porphyry copper deposit, II Region, Chile—History of the discovery: London, Institution of Mining and Metallurgy, Mining Latin America, p. 319–331.
Padilla Garza, R.A., Titley, S.R., and Pimental B., Francisco, 2001, Geology of the Escondida porphyry copper deposit, Antofagasta region, Chile: Economic Geology, v. 96, p. 307–324. (Also available at http://dx.doi.org/10.2113/gsecongeo.96.2.307.)Porter, T.M., ed., 2005, Super porphyry copper and gold deposits—A global perspective: Adelaide, PGC Publishing, v. 1, 280 p. (Abstract also available at http://www.portergeo.com.au/publishing/superporphyry/superpstart.html.)Richards, J.R., Boyce, A.J., and Pringle, M.S., 2001, Geologic evolution of the Escondida area, northern Chile—A model for spatial and temporal localization of porphyry Cu mineralization: Economic Geology, v. 96, p. 271–305. (Also available at http://dx.doi.org/10.2113/gsecongeo.96.2.271.)Sillitoe, R.H., and McKee, E.H., 1996, Age of supergene oxidation and enrichment in the Chilean porphyry copper province: Economic Geology, v. 91, p. 164–179. (Also available at http://dx.doi.org/10.2113/gsecongeo.91.1.164.)Singer, D.A., Berger, V.I., and Moring, B.C., 2008, Porphyry copper deposits of the world—Database and grade and tonnage models, 2008: U.S. Geological Survey Open-File Report 2008-1155, [45] p. and digital data, accessed December 31, 2013, at http://pubs.usgs.gov/of/2008/1155/.Tarkian, M., and Stribrny, B., 1999, Platinum-group elements in porphyry copper deposits—A reconnaissance study: Mineralogy and Petrology, v. 65, p. 161–183. (Also available at http://dx.doi.org/10.1007/BF01161959.)
Zappettini, Eduardo; Miranda-Angles, Vitaliano; Rodriguez S., Carolina; Palacios, Oscar; Cocking,Robert; Godeas, Marta; Uribe-Zeballos, Hernán; Vivallo S., Waldo; Paz, M.M.; Seggiaro, Raúl; Heuschmidt, Bertand; Gardeweg P., Moyra; Boulangger Rondoy, Elmere; Korzeniewski, Lidia I.; Mpodozis M., Constantino; Carpio R., Mario; and Rubiolo, Daniel, 2001, Mapa metalogénico de laregión fronteriza entre Argentina, Bolivia, Chile y Perú (14ºS–28ºS): Santiago, Chile, Servicio Nacional de Geología y Minería, Publicacion Geológica Multinacional No. 2, 222 p., 1 map, scale 1:1,000,000.