Unnamed (east of outer Squid Bay)

Prospect, Probably inactive

Commodities and mineralogy

Main commodities Cu; Ni
Ore minerals chalcopyrite; pentlandite; pyrite; pyrrhotite

Geographic location

Quadrangle map, 1:250,000-scale SI
Quadrangle map, 1:63,360-scale D-8
Latitude 57.8824
Longitude -136.47
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is at an elevation of about 50 feet, east of outer Squid Bay and about 2.5 miles north of the south tip of Yakobi Island. The prospect is about 0.4 mile north-northeast of the center of sec. 15, T. 46 S., R. 55 E. It is location P-10 of Bittenbender and others (1999) and MAS no. 0021140079 (U.S. Bureau of Land Management, 2002). The location is accurate within about 0.2 mile.

Geologic setting

Geologic description

Johnson and Karl (1985) map the rocks in the Squid Bay area as Cretaceous graywacke intruded by Tertiary gabbronorite and tonalite. Bittenbender and others (1999), citing the work of Kimball (1982) and Loney and others (1975), describe the prospect as a magmatic segregation, copper-nickel deposit in gabbronorite. A composite grab sample contained 0.38 percent copper and 0.05 percent nickel. These values and the geologic setting of the deposit suggest that the ore minerals probably are chalcopyrite, pentlandite, pyrrhotite, and pyrite, as they are, for example, at the nearly Bohemia Basin deposit (SI001).
Geologic map unit (-136.471845077385, 57.8820215014371)
Mineral deposit model Duluth Cu-Ni-PGE (Cox and Singer, 1986; model 5a).
Mineral deposit model number 5a
Age of mineralization The deposit probably is roughly contemporaneous with intrusion of the Tertiary gabbronorite host rock.

Production and reserves

Workings or exploration Only surface sampling.
Indication of production None

Additional comments

The prospect is in West Chichagof-Yakobi Wilderness.

References

References

Bittenbender, P., Still, J.C., Maas, K., and McDonald, M., Jr., 1999, Mineral resources of the Chichagof and Baranof Islands area, southeast Alaska: Bureau of Land Management, BLM-Alaska Technical Report 19, 222 p.
U.S. Bureau of Land Management, 2002, Alaska mineral locations database report (Sitka quadrangle), July 2, 2002, 205 p. [http://imcg.wr.usgs.gov/dem.html]
Reporters H.C. Berg (U.S. Geological Survey)
Last report date 10/16/2004