Unnamed (head of Sheep Creek) (ARDF #WI014) Ag, Cu

Unnamed (head of Sheep Creek)

Prospect, Inactive

Commodities and mineralogy

Main commodities	Ag; Cu
Other commodities	Au; Pb
Ore minerals	azurite; bornite; chalcopyrite; galena; malachite

Geographic location

Quadrangle map, 1:250,000-scale	WI
Quadrangle map, 1:63,360-scale	C-4
Latitude	67.5828
Longitude	-151.9188
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This prospect is at an elevation of about 3,500 feet, about 3.0 miles south of Pet Lake near the center of section 24, T. 32 N., R. 20 W. The location is accurate.

Geologic setting

Geologic description This prospect is one of several in a northeast-trending zone with minor copper mineralization that extends for about 5 miles northeast of VABM Allen (also see WI005, 006, 012, 013, and 016). Prior to the mid-1970s, at least five companies including Bear Creek Mining Company, General Crude Oil Company, New Jersey Zinc Company, Alvenco Inc., and BP Alaska prospected and sampled along this belt (Degenhart and others, 1978). Most of these prospects consist of malachite, azurite, and chalcopyrite along a thrust-fault contact that separates Devonian, Skajit Limestone from underlying chloritic schist (Dillon and others, 1986). At this location, a small pod of copper mineralization, no more than 5 feet in diameter, is in marble (Degenhart and others, 1978). A sample, said to represent the mineralization contained 5,700 parts per million (ppm) copper, 3.4 ppm silver, and 10 parts per billion (ppb) gold. Kurtak and others (2002) also described podiform copper mineralization in this area. A sample of schist with bornite, malachite, and possibly galena contained 11 percent copper, 17 ppb gold, and 68.9 ppm silver. A sample of a small quartz vein contained 16.5 percent copper and and 78.6 ppm silver.
Geologic map unit	(-151.921556998206, 67.5823453745046)
Mineral deposit model	Insufficient evidence to assign.
Age of mineralization	Devonian or younger based on the age of the host rocks.
Alteration of deposit	None specified.

Production and reserves

Workings or exploration	This prospect is one of several in a northeast-trending zone of minor copper mineralization that extends for about 5 miles northeast of VABM Allen (also see WI005, 006, 012, 013, and 016). Prior to the mid-1970s, at least five companies including Bear Creek Mining Company, General Crude Oil Company, New Jersey Zinc Company, Alvenco Inc., and BP Alaska prospected and sampled along this belt (Degenhart, and others, 1978). It was investigated and sampled by the Bureau of Land Management in about 2000 (Kurtak and others, 2002).
Indication of production	None
Reserve estimates	None.
Production notes	None.

References

MRDS Number	A011933
References Degenhart, C.E., Griffis, R.J., McQuat, J.F., and Bigelow, C.G., 1978, Mineral studies of the western Brooks Range performed under contract to the U.S. Bureau of Mines, Contract #JO155089: U.S. Bureau of Mines Open-File Report 103-78, 529 p., 11 sheets. Kurtak, J.M., Klieforth, R.F., Clark, J.M., and Maclean, E.A., 2002, Mineral investigations in the Koyukuk mining district, northern Alaska: Final Report: U.S. Bureau of Land Management Technical Report 50, 2 vols., 845 p.
Reporters	J.M. Britton (Anchorage); D.J. Grybeck (Contractor, USGS)
Last report date	2/1/2011