Hayes Glacier East

Prospect, Inactive

Commodities and mineralogy

Main commodities Cu; Zn
Other commodities Ag; Pb
Ore minerals chalcopyrite; galena; pyrite; pyrrhotite; sphalerite

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale C-6
Latitude 63.6858
Longitude -146.5556
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is at an elevation of about 4,900 feet, south of the end of the Hayes Glacier. It is about 2.6 miles west of VABM 4862 'Glacier' and about 0.2 mile east-southeast of the center of section 22, T. 14 S., R. 6 E.

Geologic setting

Geologic description

The rocks in the area are derived from Devonian felsic to intermediate volcanic rocks, mainly andesite, dacite, and quartz keratophyre flows and tuffs, and from Devonian or older shale, marl, and marble (Nokleberg and others, 1992 [MF]; 2002 [\Open-File]; Bittenbender and others, 2007). The rocks were intensely deformed into chlorite schist, limestone, and greenstone that were first metamorphosed to lower amphibolite facies in the Early Cretaceous and then retrograded to lower greenschist facies in the mid-Cretaceous.
Resource Associated of Alaska was active in the area in 1970s but they deeded their claims to the Cook Inlet Region Incorporated in 1980 (Bittenbender and others, 2007). The prospect was examined and sampled by the U.S. Geological Survey in about 1990 (Nokleberg and others, 1991), by the American Copper and Nickel Company in 1993, and by the Bureau of Land Management in the early 2000s. There are no workings on the prospect.
Samples taken during a U.S. Geological Survey reconnaissance in the 1980s consisted of disseminated to semi-massive pyrite, chalcopyrite, galena, sphalerite, and pyrrhotite in chlorite-epidote-carbonate schist (Nokleberg and others, 1991). A grab sample of chalcopyrite-bearing schist contained 0.92 percent copper, 0.22 percent zinc, 0.06 percent lead, and 10 parts per million (ppm) silver.
Bittenbender and others (2007) identified thin, massive-sulfide lenses and stringers in several horizons from 4,700 to 4,950 feet in elevation. The mineralization can be traced for about 0.8 mile along strike in zones that trend east and dip about 60 degrees south. The massive sulfides lenses and stringers are generally less than 1.5 feet thick and consist mainly of pyrrhotite with minor chalcopyrite, pyrite, and galena. Samples contained up to 29.4 ppm silver, 2.4 ppm gold, 3,470 ppm lead, 1.94 percent copper, and 1,140 ppm zinc.
Geologic map unit (-146.55789295964, 63.6853849889129)
Mineral deposit model Kuroko massive sulfide (Cox and Singer, 1986; model 28a).
Mineral deposit model number 28a
Age of mineralization Probably Devonian, the pre-metamorphic age of the host rocks.
Alteration of deposit Not specifically noted. The mineralization and host rocks have been subject to regional amphibolite- and greenschist-facies metamorphism in the Cretaceous.

Production and reserves

Workings or exploration Resource Associated of Alaska was active in the area in 1970s but they deeded their claims to the Cook Inlet Region Incorporated in 1980 (Bittenbender and others, 2007). The prospect was examined and sampled by the U.S. Geological Survey in about 1990 (Nokleberg and others, 1991), by the American Copper and Nickel Company in 1993, and by the Bureau of Land Management in the early 2000s. There are no workings on the prospect.
Indication of production None

References

References

Bittenbender, P.E., Bean, K.W., Kurtak, J.M., and Deininger, James Jr., 2007, Mineral assessment of the Delta River Mining District area, east-central, Alaska: U.S. Bureau of Land Management, Alaska Technical Report 57, 675 p.
Lange, I. M., Nokleberg, W.J., Newkirk, S. R., Aleinikoff, J.N., Church, S.E., and Krouse, R.H., 1993, Devonian volcanogenic massive sulfide deposits and occurrences, southern Yukon-Tanana terrane, eastern Alaska Range, Alaska: Economic Geology, v. 88, p. 344-376.
Reporters W.T. Ellis (Alaska Earth Sciences), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (USGS); D.J. Grybeck (Contractor, USGS)
Last report date 5/13/2012