Unnamed (northwest of Port Audrey) (ARDF #SR238) Cu

Unnamed (northwest of Port Audrey)

Prospect, Inactive

Commodities and mineralogy

Main commodities	Cu
Other commodities	Ag
Ore minerals	chalcopyrite; pyrite; pyrrhotite
Gangue minerals	quartz

Geographic location

Quadrangle map, 1:250,000-scale	SR
Quadrangle map, 1:63,360-scale	B-3
Latitude	60.357
Longitude	-147.7704
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	The prospect is located on the southeast side of hill 1456 at an elevation of 1,300 feet. It is about 0.1 mile northwest of SR239. It is in the NE1/4 section 18, T. 3 N., R. 10 E., of the Seward Meridian. This is location 216 of Tysdal (1978 [MF-880-A]) and location S-61 of Jansons and others (1984). This location is accurate to within a quarter of a mile.

Geologic setting

Geologic description Bedrock in this area is greenstone of the Orca Group of early Tertiary age (Nelson and others, 1985). The prospect consists of a 10-foot-deep shaft in a 5.5-foot-wide shear zone containing chloritic schist and a massive quartz lens (Kurtak and Jeske, 1986). A 5-inch-wide zone of sulfide-bearing schist occurs within the massive quartz lens. The quartz lens contains as much as 10 percent pyrite and traces of chalcopyrite (Kurtak and Jeske, 1986). Samples from the collar of the shaft contained from 20 to 480 ppm copper and 0.5 to 1.3 ppm silver (Kurtak and Jeske, 1986).
Geologic map unit	(-147.772452111156, 60.3564378266923)
Mineral deposit model	Cyprus massive sulfide (Cox and Singer, 1986; model 24a)
Mineral deposit model number	24a
Age of mineralization	Tertiary or younger; the mineralization is in rocks of the Orca Group of Tertiary age.

Production and reserves

Workings or exploration	Workings consist of a single 10-foot-deep shaft that explores a mineralized shear zone. Samples from the collar of the shaft contained from 20 to 480 ppm copper and 0.5 to 1.3 ppm silver (Kurtak and Jeske, 1986).
Indication of production	None

References

References Jansons, Uldis, Hoekzema, R.B., Kurtak, J.M., and Fechner, S.A., 1984, Mineral occurrences in the Chugach National Forest, southcentral Alaska: U.S. Bureau of Mines Mineral Land Assessment 5-84, 218 p., 2 sheets, scale 1:250,000. Kurtak, J.M., and Jeske, R.E., 1986, Mineral investigations in the Chugach National Forest, Alaska (Islands area): U.S. Bureau of Mines Open-File Report 54-86, 302 p., 1 sheet, scale 1:63,360. Nelson, S.W., Dumoulin, J. A., and Miller, M.L., 1985, Geologic map of the Chugach National Forest, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1645-B, 16 p., 1 sheet, scale 1:250,000. Richter, D.H., 1965, Geology and mineral deposits of central Knight Island, Prince William Sound, Alaska: Alaska Division of Mines and Minerals Geologic Report 16, 40 p., 1 sheet, scale 1:40,000. Tysdal, R.G., 1978, Mines, prospects, and occurrences map of the Seward and Blying Sound quadrangles, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-880-A, 2 sheets, scale 1:250,000.
Reporters	Jeff A. Huber and Carol S. Huber (Anchorage)
Last report date	1/2/2002