Porphyry copper deposit in Cajamarca, Peru

Names and other identifiers

Tract name Peru-Ecuador middle–late Miocene La Granja (005pCu1006)
Site status deposit

Geographic location

Country Peru
State or province Cajamarca
Geographic location -78.322222222, -7.3
Geologic map unit -78.322222222, -7.3
Nearby data

Geologic information

Deposit type Porphyry copper
Age (Ma) 20Ma
Age determination method Ar-Ar
Age range 20.02 ±0.15 Ma
Age reference Noble and others (2004)
Minerals aikinite, alabandite, alunite, anhydrite, arsenic, arsenopyrite, barite, biotite, bornite, carbonate, chalcocite, chalcopyrite, chlorite, clay minerals, covellite, enargite, galena, gypsum, hematite, huebnerite, jarosite, kaolinite, magnetite, marcasite, molybdenite, pyrite, pyrophyllite, pyrrhotite, rhodochrosite, rhodonite, scheelite, sericite, serpentine, sphalerite, stephanite, sternbergite, talc, tennantite/tetrahedrite, tourmaline, wolframite
Associated rocks breccia, hornfels, diorite porphyry, quartz monzonite porphyry, skarn, granodiorite porphyry, limestone, quartzite
Tectonic setting continental margin
Stratigraphic age Miocene

Commodity and development information

Development status Prospect
Major commodities Cu, Mo, Au, Ag
Tonnage (Mt) 700Mt
Cu grade (%) 0.65%
Mo grade (%) 0.022%
Au grade (g/t) 0.14g/t
Ag grade (g/t) 0.6g/t
Contained copper 4,600,000t
Gold-Moly ratio 6.7

Reference information

Comments 5% of the deposit area covered by glacial debris.
Study area name Andes
References Clark (1993); Davies and Williams (2005); Hart (1991); Hollister and Sirvas (1974); Long (1995); Noble and others (2004); Sillitoe (1988); Singer and others (2008)
Site reference Cunningham and others (2008)
Clark, A.H., 1993, Are outsize porphyry copper deposits either anatomically or environmentally distinctive?, in Whiting, B.H., Hodgson, C.J., and Mason, R., eds., Giant ore deposits: Society of Economic Geologists Special Publication 2, p. 213–283.
Davies, C.R., and Williams, P.J., 2005, The El Galeno and Michiquillay porphyry Cu-Au-Mo deposits—Geological descriptions and comparison of Miocene porphyry systems in the Cajamarca district, northern Peru: Mineralium Deposita, v. 40, p. 598–616. (Also available at http://dx.doi.org/10.1007/s00126-005-0026-6.)
Hart, L.H., 1991, Who is the true discoverer of the Michiquillay porphyry copper deposit, in Hollister, V.F., ed., Porphyry copper, molybdenum, and gold deposits, volcanogenic deposits (massive sulfide), and deposits in layered rock—Case histories of mineral discoveries: Littleton, Colorado, Society of Mining, Metallurgy, and Exploration, Inc., v. 3, p. 33–34.
Hollister, V.F., and Sirvas, E.B., 1974, The Michiquillay porphyry copper deposit: Mineralium Deposita, v. 9, p. 261–269. (Also available at http://dx.doi.org/10.1007%2FBF00204000.)
Long, K.R., 1995, Production and reserves of Cordilleran (Alaska to Chile) porphyry copper deposits, in Pierce, F.W., and Bolm, J.G., eds., Porphyry copper deposits of the American Cordillera: Tucson, Arizona Geological Society Digest 20, p. 35–68.
Noble, D.C., Vidal, C.E., Perelló, J., and Rodríguez, O.P., 2004, Space-time relationships of some porphyry Cu-Au, epithermal Au, and other magmatic-related mineral deposits in northern Peru, in Sillitoe, R.H., Perelló, J., Vidal, C., eds., Andean metallogeny—New discoveries, concepts and updates: Society of Economic Geologists Special Publication 11, p. 313–318.
Sillitoe, R.H., 1988, Epochs of intrusion-related copper mineralization in the Andes: Journal of South American Earth Sciences, v. 1, no. 1, p. 89–108. (Also available at http://dx.doi.org/10.1016/0895-9811(88)90018-1.)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/.