Porphyry copper prospect in Töv, Mongolia

Names and other identifiers

Alternate names Bajan-Ula, Bayan-Uul 2
Tract name Mongol-Altai (142pCu8507)
Site status prospect

Geographic location

Country Mongolia
State or province Töv
Geographic location 104.8833, 46.6833
Geologic map unit 104.8833, 46.6833
Nearby data

Geologic information

Deposit type Porphyry copper
Age (Ma) 222Ma
Age determination method K-Ar biotite
Age range 222.0 ±2.1 Ma; 222.4 ±2.2 Ma
Age reference Lamb and Cox (1998)
Minerals actinolite, albite, biotite, bornite, carbonate, chalcocite, chalcopyrite, chlorite, covellite, epidote, fahlore, galena, galenobismutite, hematite, kaolinite, magnetite, malachite, marcasite, molybdenite, montmorillonite, muscovite/sericite, pyrite, pyrophyllite, pyrrhotite, rutile, sphalerite, tourmaline
Associated rocks andesite porphyry, breccia, granodiorite porphyry, quartz monzodiorite porphyry, quartz syenite porphyry,n.d.,andesite dike, andesitic trachybasalt, granite, granodiorite, trachyandesite, tuff-breccia, tuff-conglomerate, tuffaceous sandstone, tuffaceous volcanic-plutonic system, porphyritic diorite to granite
Tectonic setting continental margin
Stratigraphic age Late Triassic

Commodity and development information

Development status Prospect
Major commodities Cu, Mo
Minor commodities Au
Gold-Moly ratio -9999

Reference information

Comments An area 0.6 by 2.3 km, >0.1% Cu, >0.002% Mo, >0.1 g/t Au. A zone 300 by 900 m contains >0.3 weight percent Cu and 0.005 weight percent Mo. Abundant quartz-tourmaline-chalcopyrite veins and quartz-tourmaline breccias (Lamb and Cox, 1998); exposed; a 39Ar/40Ar isotopic age is 220–233 Ma (Late Triassic) from Nokleberg and others (2003). Alteration zone is nearly oval, is 3 km wide and extends northeast for 5 km. The dominance of sericite, advanced argillic, silica alteration at the surface suggests a relatively shallow porphyry Cu system. The deposit consists of stockwork veinlets and veins of quartz, pyrite, chalcopyrite, and molybdenite that occur in or near porphyritic intrusions. High-level intrusive porphyry is contemporaneous with abundant dikes, faults, and breccia pipes. Hosted in a Jurassic volcanic-plutonic system that includes small porphyritic intrusions of diorite to granite from Nokleberg and others (2003).
Study area name Central Asian Orogenic Belt
References Koval and others (1988); Koval and others (1989); Lamb and Cox (1998); Nokleberg and others (1999); Nokleberg and others (2003); Sillitoe, Gerel, and others (1996); Singer and others (2008); Kirkham and Dunne (2000); Dejidmaa and others (2002)
Site reference Mihalasky, Ludington, Hammarstrom, and others (2015)
Dejidmaa, G., Bujinlkham, B., Ganbaatar, T., Oyuntuya, N., Enkhtuya, B., Eviihuu, A., and Monkh-Erdene, N., 2002, Distribution map of mineral deposits and occurrences in Mongolia: Ulaanbaatar, Mongolia Mineral Resources Authority, Geologic Information Center, 540 p., 12 sheets, scale 1:1,000,000.
Kirkham, R.V., and Dunne, K.P.E., comps., 2000, World distribution of porphyry, porphyry-associated skarn, and bulk-tonnage epithermal deposits and occurrences: Canada Geological Survey Open File 3792a, 26 p. and 1 diskette. (Also available at
Koval, P.V., Ariunbileg, S., Libatorov, Yu.I., and Maksimyuk, U.E., 1988, The Bayan-Uul porphyry copper-molybdenum occurrence and relation to magmatism, central Mongolia: Geology of Ore Deposits, v.3, p. 24–35.
Koval, P.V., Gotovsuren, A., Ariunbileg, S., and Libatorov, Yu.I., 1989, On prospecting for porphyry copper mineralization in intracontinental mobile zones (Mongol-Okhotsk belt, Mongolian People‘s Republic): Journal of Geochemical Exploration, v. 32, p. 369–380. (Also available at, M.A. and Cox, Dennis, 1998, New 40Ar/39Ar age data and implications for porphyry copper deposits of Mongolia: Economic Geolology, v. 93, p. 524–529. (Also available at, 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
Sillitoe, R.H., Gerel, O., Dejidma, G., Gotovsuren, A., Sanjaadorj, D., Baasandorj, S., and Dashiin, B.E., 1996, Mongolia’s gold potential: Mining Magazine, July 1996, p. 12–15.
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