Unnamed (upper Edgar Creek)

Occurrence in Alaska, United States with commodities Copper, Gold

Geologic information

Identification information

Deposit ID 10307543
Record type Site
Current site name Unnamed (upper Edgar Creek)

Geographic coordinates

Geographic coordinates: -147.90582, 63.63263 (WGS84)
Relative position This occurrence is at an elevation of about 5,500 feet, in the eastern headwaters of upper Edgar Creek, a tributary to the Yanert Fork River. The map site is in the NE1/4 of sec. 10, T. 15 S., R. 2 W., of the Fairbanks Meridian. The location is accurate to within 2000 feet. This is location 26 of Sherwood and others (1976).
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Gold Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Malachite Ore

Nearby scientific data

(1) -147.90582, 63.63263

Comments on the geologic information

  • Geologic Description = The country rocks in the area of this occurrence are the Devonian Yanert Fork sequence, consisting mainly of siliceous mudstone, argillite, slate, phyllite, semischist, and impure quartzite. Thin interbeds of banded metachert and metavolcanic rocks are also present (Wilson and others, 1998). The bedded rocks are cut by Triassic(?) gabbroic sills and dikes. The occurrence consists of disseminations of chalcopyrite and possibly other sulfide minerals, in the metasedimentary rocks near a gabbro sill. Locally, the copper mineral(s) are oxidized to malachite. Samples contained 4,700 ppm copper and 0.4 ppm gold (Sherwood and others, 1976).
  • Age = Possibly Triassic, assuming that the mineralization is related to the gabbro.

Economic information

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Inactive

Mining district

District name Bonnifield

Comments on the workings information

  • Workings / Exploration = Surface samples only. Samples contained 4,700 ppm copper and 0.4 ppm gold (Sherwood and others, 1976).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF HE110

Bibliographic references

  • Deposit

    Sherwood, K.W., Craddock, Campbell, and Smith, T.E., 1976, Mineral occurrences in the upper Wood River, Edgar Creek, and West Fork Glacier areas, central Alaska Range: Alaska Division of Geological & Geophysical Surveys Special Report 14, 13 p.

  • Deposit

    Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Healy quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-1062, 113 p.

  • Deposit

    Wilson, F.H., Dover, J.H., Bradley, D.C., Weber, F.R., Bundtzen, T.K., and Haeussler, P.J., 1998, Geologic map of central (interior) Alaska: U.S. Geological Survey Open-File Report 98-133, 17 p., 2 sheetsm, scale 1:500,000.

Comments on the references

  • Primary Reference = Sherwood and others, 1976

Reporter information

Type Date Name Affiliation Comment
Reporter 07-APR-00 N. Van Wyck Stevens Exploration Management Corporation