Northwest orebody

Deposit with commodities copper, molybdenum, tungsten, zinc, silver, rhenium

More information at and near this site: Re-AZ00026

About this location

Feature ID Re-Mo00310
Geographic coordinates -111.045518, 31.896951
Point definition Center of orebody
Reference Barter and Kelly (1982); Figure 20.2
Date: 1982; Scale: Large (>1:24,000)

Geologic information

Commodities copper; molybdenum; tungsten; zinc; silver; rhenium (1)
Valuable materials chalcopyrite; molybdenite; scheelite; bornite; sphalerite; native copper; cuprite; chrysocolla; tenorite; chalcocite
Associated materials pyrite; garnet; galena; magnetite
Mineralization style veinlets; disseminated grains; paint; crystals
Age of mineralization 64-55 Ma
Host rock age Laramide; Mississippian; Devonian; Cambrian; Precambrian
Host unit name Twin Buttes Porphyry Complex; Ruby Star Granodiorite; Escabrosa Limestone; Martin Formation; Abrigo Formation; Bolsa Quartzite
Host lithologies quartz monzonite porphyry; porphyritic quartz monzonite; limestone; limey dolomite; siltstone; sandstone; silty quartzite; quartzite; granite
Alteration oxidation
Reference Rauschkolb, M.H., 1983, The Geology of the Northwest Orebody, Twin Buttes Mine, Pima County, Arizona: University of Arizona, Master's thesis, 179 p.
Additional references (1) John and Taylor (2016)

Descriptions from sources


“The Northwest Orebody is located northwest of the Twin Buttes fault and southwest of the porphyritic quartz monzonite. Better grade areas occur in metacarbonate rocks of the Abrigo Formation, Martin Formation, and Escabrosa Limestone.”

Barter, C.F., and Kelly, J.L., 1982, Geology of the Twin Buttes Mineral Deposit in Titley, S.R., ed., 1982, Advances in geology of the porphyry copper deposits, southwestern North America: Tucson, University of Arizona Press, p. 407-432.

Deposit models and geoenvironmental models

Type Model Reference
Deposit model Porphyry Cu-Mo John, D.A., and Taylor, R.D., 2016, By-Products of Porphyry Copper and Molybdenum Deposits in Verplanck, P.L., and Hitzman, M.W., (eds), 2016, Rare Earth and Critical Elements in Ore Deposits: Society of Economic Geologists, Inc., Reviews in Economic Geology, Volume 18, p. 137-164.
Geoenvironmental model Porphyry Cu du Bray, E.A., 1995, ed., Preliminary compilation of descriptive geoenvironmental mineral deposit models: U.S. Geological Survey Open-File Report 95-831, 272 p.

Geographic context based on the point coordinates