Geroe Creek

The Geroe Creek is a copper and molybdenum mine located in Alaska.

About the MRDS Data:

All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.

Mine Info

Satelite View

MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.

Site Name

Primary: Geroe Creek
Secondary: MAS claims

Commodity

Primary: Copper
Primary: Molybdenum

Location

State: Alaska
District: Chandalar and Koyukuk

Land Status

Not available

Holdings

Not available

Workings

Not available

Ownership

Not available

Production

Not available

Deposit

Record Type: Site
Operation Category: Prospect
Operation Type: Unknown
Years of Production:
Organization:
Significant:

Physiography

Not available

Mineral Deposit Model

Model Name: Porphyry Cu-Mo

Orebody

Not available

Structure

Not available

Alterations

Alteration Type: L
Alteration Text: Seritization and propylitization of porphyritic host rocks; quartz-sericite-chlorite plus or minus epidote; calcite.

Rocks

Name: Diorite
Role: Associated
Age Type: Associated Rock Unit
Age Young: Late Cretaceous

Analytical Data

Not available

Materials

Ore: Chalcopyrite
Ore: Molybdenite
Gangue: Chlorite
Gangue: Quartz
Gangue: Sericite

Comments

Comment (Deposit): Model Name = Porphyry Cu-Mo (Cox and Singer, 1986; model 21a)

Comment (Deposit): Other Comments = See also: Venus (CH065), Victor (CH064), Eva (CH063) and Evelyn Lee (CH059) prospects; Alaska Kardex No. 031-68 (Kardex is a card file mining claim information system located at the State of Alaska DNR Public Information Center in Fairbanks).

Comment (Commodity): Ore Material = Copper sulfides (chalcopyrite)

Comment (Geology): Age = Devonian based on reported Early Devonian Pb/Pb zircon ages from the associated Baby Creek batholith and Horace Mountain plutons (Dillon and others, 1996).

Comment (Exploration): Status = Inactive

Comment (Reference): Primary Reference = Newberry and others, 1986

Comment (Workings): Workings / Exploration = 239 claims staked in 1975 and 1976.

Comment (Geology): Geologic Description = The Geroe Creek prospect is one of several quartz stockworks and altered zones in the northeast-trending belt of Devonian peraluminous biotite-muscovite granites of the Baby Creek batholith and the Devonian metaluminous biotite-hornblende granites and granodiorites of the Horace Mountain plutons (Newberry and others, 1986). Porphyritic phases are locally present in these plutons, and Young and others (1997) reported that the mineralizing intrusives are porphyritic meta-granodiorites and biotite meta-granites. The country rocks are mainly Paleozoic schists and marble along with peraluminous meta-granodiorite. Young and others (1997) also noted that there is no skarn development in the calcareous rocks. The veinlets in the stockworks on the Geroe prospect contain disseminated molybdenite, chalcopyrite, and pyrite along with intense quartz-sericite-chlorite plus or minus epidote alteration. Eakins and others (1983, p. 41) reported Mo grades as much as 0.1 percent, and Nokleberg and others (1987) report that zones in the plutons as much as several meters thick contain values of 0.6 percent Cu, 0.02 percent Mo, and 0.1 grams of gold per ton.

References

Reference (Deposit): Newberry, R.J., Dillon, J.T., and Adams, D.D., 1986, Regionally metamorphosed calc-silicate-hosted deposits of the Brooks Range, northern Alaska: Economic Geology, v. 81, p. 1728-1752

Reference (Deposit): Eakins, G.R., Bundtzen, T.K., Robinson, M.S., Clough, J.G., Green, C.B., Clautice, K.H., and Albanese M.A., 1983, Alaska's mineral industry, 1982, Alaska Division of Geological and Geophysical Surveys Special Report 31, 63 p.

Reference (Deposit): Bundtzen, T.K., Eakins, G.R., and Conwell, C.N., 1982, Alaska mineral resources 1981-82: Alaska Division of Geological and Geophysical Surveys Annual Report 1981-82, 153 p., 4 sheets, scale 1:2,500,000.

Reference (Deposit): Young, L.E., St. George, P., and Bouley, B., 1997, Porphyry copper deposits in relation to the magmatic history and palinspastic restoration of Alaska, in Goldfarb, R.J., and Miller, L.D., (eds.), Mineral deposits of Alaska: Economic Geology Monograph 9, p. 306-333.

Reference (Deposit): Grybeck, D.J., 1977, Known mineral deposits of the Brooks Range, Alaska: US Geological Survey Open-File Report 77-166C, 41 p., 1 sheet, scale 1:1,000,000.

Reference (Deposit): Arctic Environmental Information and Data Center, 1982, Mineral terranes of Alaska: University of Alaska, Fairbanks, 7 sheets, scale 1:1,000,000.

Reference (Deposit): 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.

Reference (Deposit): Bundtzen, T.K., Eakins, G.R., and Conwell, C.N., 1982, Review of Alaska mineral resources 1981: Alaska Division of Geological and Geophysical Surveys Annual Report 1981, 48 p., 2 sheets, scale 1:3,000,000.

Reference (Deposit): DeYoung, J.H., Jr., 1978, Mineral resources map of the Chandalar quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-878-B, 2 sheets, scale 1:250,000.

Reference (Deposit): U.S. Bureau of Mines, 1973, Alaska 1:250,000-scale quadrangle map overlays showing mineral deposit locations, principal minerals, and number and type of claims: U.S. Bureau of Mines Open-File Report 20-73, 95 overlays (updated in 1986, 1987).

Reference (Deposit): Maas, K.M., 1987, Maps summarizing land availability for mineral exploration and development in northern Alaska, 1986: U.S. Bureau of Mines Open-File Report 10-87, 33 sheets.

Reference (Deposit): Nokleberg, W.J., Bundtzen, T.K., Berg, H.C., Brew, D.A., Grybeck, Donald, Robinson, M.S., Smith, T.E., and Yeend, Warren, 1988, Metallogeny and major mineral deposits of Alaska: U.S. Geological Survey Open-File Report 88-73, 97 p., 2 plates, scale 1:5,000,000.

Reference (Deposit): Nokleberg, W.J., Bundtzen, T.K., Grybeck, D.J., Koch, R.D., Eremin, R.A., Rozenblum, I. S., Sidorov, A.A., Byalobzhesky, S.G., Sosunov, G.M., Shpikerman, V.I., Gorodinsky, M.E., 1993, Metallogenesis of mainland Alaska and the Russian Northeast: U.S. Geological Survey Open-File Report 93-0339, 3 sheets, 230 p.

The Top Ten Gold Producing States

These ten states contributed the most to the gold production that built the West from 1848 through the 1930s. The Top Ten Gold Producing States.