Porphyry copper prospect in Ömnögovi, Mongolia

Names and other identifiers

Tract name Oyu Tolgoi (142pCu8506)
Site status prospect

Geographic location

Country Mongolia
State or province Ömnögovi
Geographic location 107.6962, 43.942
Geologic map unit 107.6962, 43.942
Nearby data

Geologic information

Deposit type Porphyry copper
Age (Ma) 321Ma
Age determination method Rb-Sr
Age range 321 ±9 Ma
Age reference Batkhishig and others (2010)
Minerals bornite, chalcopyrite, pyrite
Associated rocks diorite porphyry, granite porphyry, monzodiorite porphyry, quartz syenite porphyry, ndesite, diorite, granodiorite, monzonite, tuff, tuff breccia, tuffaceous sandstone, tuffaceous siltstone
Tectonic setting island arc
Stratigraphic age Carboniferous

Commodity and development information

Development status Prospect
Major commodities Cu
Gold-Moly ratio -9999

Reference information

Comments Magmatic ring structure with diameter about 15 km, includes widespread advanced argillic alteration (alunite). Cu-bearing tourmaline breccias are common. Area was explored by Czech-Mongolian expedition in 1980s and became an Ivanhoe prospect in 2002. Geochemisty of igneous rocks, including Sr/Y ratios, indicates an ""adakitic"" composition, favorable for porphyry Cu mineralization. 325.5 ±1 Ma, U-Pb (Blight and others, 2010); 321 ±9 Ma, Rb-Sr (Batkhishig and others, 2010). Alternate location (43.949812 N latitude and 107.643657 E longitude) is in the center of a region which appears to show wide trenching E, W, and S., and a drill pad SW of the point; also Singer and others (2008) approximately 27 km NW of point: 44.166667 N latitude and 107.5 E longitude.
Study area name Central Asian Orogenic Belt
References Singer and others (2008); Ivanhoe Mines Ltd. (2002b); Ivanhoe Mines Ltd. (2003b); Singer and others (2005); Bignall and others (2005); Ooka and others (1998); Batkhishig and others (2010); Blight and others (2010); Nokleberg and others (1999); Nokleberg and others (2003)
Site reference Mihalasky, Ludington, Hammarstrom, and others (2015)
Batkhishig, Bayaraa; Noriyoshi, Tsuchiya; and Bignall, Greg, 2010, Magmatism of the Shuteen complex and Carboniferous subduction of the Gurvansaikhan terrane, south Mongolia: Journal of Asian Earth Sciences, v. 37, p. 399–411. (Also available at
Bignall, Greg; Batkhishig, Bayaraa; and Tsuchiya, Noriyoshi, 2005, The Shuteen Cu–Au porphyry deposit, in Seltmann, Reimar; Gerel, Ochir; and Kirwin, Douglas, eds., Geodynamics and metallogeny of Mongolia with a special emphasis on copper and gold deposits: Society for Geology Applied to Mineral Deposits (SGA) Biennial Meeting, 8th, August 14–16, 2005, Beijing, IAGOD Guidebook Series 11, SEG-IAGOD Field Trip ""Copper and Gold Deposits of Mongolia”, p. 193–201.
Blight, J.H.S., Crowley, Q.C., Petterson, M.G., and Cunningham, Dickson, 2010, Granites of the southern Mongolia Carboniferous arc—New geochronological and goechemical constraints: Lithos, v. 116, p. 35–52. (Also available at Mines Ltd., 2002b, Ivanhoe Mines acquires important new porphyry gold and copper discovery areas in the South Gobi region of Mongolia: Ivanhoe Mines Ltd. press release, March 13, 2002, 1 p., accessed December 4, 2013, at
Ivanhoe Mines Ltd., 2003b, Shuteen: Ivanhoe Mines Ltd. Web page accessed May 3, 2012, at [Web page no longer available.]
Nokleberg, W.J., Naumova, V.V., Kuzmin, M.I., and Bounaeva, T.V., eds., 1999, Preliminary publications book 1 from project on mineral resources, metallogenesis, and tectonics of northeast Asia: U.S. Geological Survey Open-File Report 99-165, 6 p. and digital data, CD-ROM. (Also available at, W.J., Bounaeva, T.M., Miller, R.J., Seminskiy, Z.V., and Diggles, M.F. eds., 2003, Significant metalliferous and selected non-metalliferous lode deposits, and selected placer districts of northeast Asia: U.S. Geological Survey Open-File Report 03-220, 422 p., CD-ROM. (Also available at, Takashi; Metsugi, Hideya; Kaku, Manabu; and Adachi, Kazuhiro, 1998, Extraction of clay mineral alteration zone in eastern Mongolia using JERS-1 data: Japan Geological Survey Bulletin, v. 49, no. 6, p. 275–290. (Also available at, D.A., Berger, V.I., and Moring, B.C., 2005, Porphyry copper deposits of the world—Database, map, and grade and tonnage models: U.S. Geological Survey Open-file Report 2005-1060, [9] p. and digital data, accessed December 31, 2013, at, 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