Main commodities | Cu |
---|---|
Other commodities | Mo |
Ore minerals | azurite; bornite; chalcocite; chalcopyrite; covellite; malachite |
Gangue minerals | quartz |
Quadrangle map, 1:250,000-scale | WI |
---|---|
Quadrangle map, 1:63,360-scale | C-5 |
Latitude | 67.5469 |
Longitude | -152.0431 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | This prospect is in a high saddle about 0.8 mile east-northeast of VABM Allen and about 4 miles northeast of the junction of Sheep Creek and John River. The prospect is at an elevation of about 4,000 feet near the southeast corner of section 32, T. 32 N., R. 20 W.. The location is accurate. |
Geologic descriptionBrosge and Reiser (1960) described copper sulfides and malachite at this prospect in fault contact between Devonian Skajit Limestone and a Devonian phyllite and siltstone unit. Dillon and others (1981, sample 284) described disseminated covellite and bornite and malachite stain in pale-green calc-schist and quartz veins. A sample contained up to 5,000 parts per million (ppm) copper and 10 ppm molybdenum. Kurtak and others (2002) analyzed one rock sample of chlorite-quartz schist that contained chalcocite, malachite and azurite. It contained 1,664 ppm copper, 4.8 ppm silver, and 23 parts per billion (ppb) gold. Degenhart and others (1978) reported minor amounts of chalcopyrite, bornite and malachite in metamorphosed, reef limestone near VABM Allen, only a short distance west of this location. 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 in the area as part of their work in a 5-mile-long, northeast-trending belt of mineral occurrences along a thrust fault (Degenhart, and others, 1978). | |
Geologic map unit | (-152.045857247198, 67.5464430549741) |
---|---|
Mineral deposit model | Unclear from the limited information. |
Age of mineralization | Devonian or younger based on the age of the host rocks. |
Alteration of deposit | Local oxidation of copper minerals. |
Workings or exploration | 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 in the area as part of their work in a 5-mile-long, northeast-trending belt of mineral occurrences along a thrust fault (Degenhart and others, 1978). Examined and sampled by the U.S. Geological Survey (Brosge and Reiser, 1960), the Alaska Division of Geological and Geophysical Survey (Dillon and others, 1981), and the Bureau of Land Management (Kurtak and others, 2002). |
---|---|
Indication of production | None |
Reserve estimates | None. |
Production notes | None. |
Additional commentsSee also WI016 and WI006. |
MRDS Number | A011951; A011985 |
---|---|
ReferencesKurtak, 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 |