Commodities
PrimaryGold, Copper, Lead, Zinc
Commodity typeM
Deposit
Model184: Massive sulfide, kuroko
Materials
Ore mineralsChalcopyrite, Galena, Gold, Pyrite, Sphalerite
GangueAnhydrite, Barite, Chlorite, Sericite
Geology
AlterationThe alteration at Johnson River can be divide into two main events. An early stage of nodular anhydrite and fine-grained disseminated pyrite is accompanied by Mg-chlorite, sericite, monmorillonite and or calcite. This alteration is either barren or weakly anomalous in base metal mineralization. The later alteration consists of silicification and sulfidation accompanied by iron-chlorite, sericite, barite, carbonate, and vein anhydrite. This stage alteration includes all the mineralization at Johnson River (Steefel, 1987).
Economic & production
Development statusProspect
Identification
Deposit ID10308616
Alternate namesJohnson River
RegionNA
Data scoreB
Coordinates60.12045, -152.95663
References
Detterman, R.L., Reed, B.L., and Lamphere, A.A., 1965, Jurassic plutonism in the Cook Inlet region, Alaska: U.S. Geological Survey Professional Paper 525-D, p. D16-D21.Detterman, R.L., and Hartsock, J.L., 1966, Geology of the Iniskin-Tuxedni region, Alaska: U.S. Geological Survey Professional Paper 512, 78 p.Steefel, C.I., 1987, The Johnson River Prospect, Alaska: Gold rich sea-floor mineralization from the Jurassic: Economic Geology, V. 82, p. 894-914.Nokleberg, W.J., Bundtzen, T.K., Berg, H.C., Brew, D.A., Grybeck, D.J., Robinson, M.S., Smith, T.E., and Yeend, W., 1987, Significant metalliferous lode deposits and placer districts of Alaska: U.S. Geological Survey Bulletin 1786, 104 p.Swainbank, R.C., Bundtzen, T. K., Clough A.H., and Henning, M.W., 1997, Alaska's mineral industry 1996: Alaska Division of Geological and Geophysical Surveys Special Report 51, 68 p.