Unnamed (above Northeast Cove) (ARDF #SR248) Cu

Unnamed (above Northeast Cove)

Prospect, Inactive

Commodities and mineralogy

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

Geographic location

Quadrangle map, 1:250,000-scale	SR
Quadrangle map, 1:63,360-scale	B-2
Latitude	60.33
Longitude	-147.7328
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	The prospect is located 0.7 mile north of the head of Northeast Cove of Drier Bay and is at an elevation of about 1,000 feet. It is the SW1/4 section 21, T. 3 N., R. 10 E., of the Seward Meridian. This is location S-57 of Jansons and others (1984). This location is accurate to within a quarter of a mile.

Geologic setting

Geologic description The prospect consists of a 4-foot- by 20-foot open cut exposing interbedded graywacke and slate that contains a silicified, sulfide-bearing zone (Kurtak and Jeske, 1986). The slate and graywacke unit is roughly 300 by 1,000 feet and is enclosed by greenstone; both units are mapped as Orca Group of early Tertiary age (Nelson and others, 1985). The siliceous sulfide-bearing zone varies from 6 inches to 3 feet wide and contains from 5 to 30 percent sulfide minerals. These minerals consist of pyrite, chalcopyrite, and some covellite (Kurtak and Jeske, 1986). Samples from the open cut contained from 25 ppm to 3.8 percent copper and from 0.2 to 28 ppm silver (Kurtak and Jeske, 1986).
Geologic map unit	(-147.734837561673, 60.3294264827469)
Mineral deposit model	Besshi massive sulfide (Cox and Singer, 1986; model 24b)
Mineral deposit model number	24b
Age of mineralization	Tertiary or younger; the mineralization is in rocks of the Orca Group of Tertiary age.
Alteration of deposit	The mineralization is in silicified slate, but no details about the alteration are given (Kurtak and Jeske, 1986).

Production and reserves

Workings or exploration	Workings on the prospect are a 5- by 35-foot open cut (Kurtak and Jeske, 1986). Samples from the open cut yielded from 25 ppm to 3.8 percent copper and from 0.2 to 28 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.
Reporters	Jeff A. Huber and Carol S. Huber (Anchorage)
Last report date	11/15/2001