Unnamed (below McCune/Heney Glaciers)

Occurrences, Inactive

Commodities and mineralogy

Main commodities Au; Pb
Ore minerals galena; pyrrhotite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale CV
Quadrangle map, 1:63,360-scale D-3
Latitude 60.92
Longitude -144.75
Nearby scientific data Find additional scientific data near this location
Location and accuracy This site includes a placer occurrence and a lode occurrence. The placer occurrence includes the drainage below McCune Glacier and the southern outwash area of Heney Glacier. The placer covers an area of about 3 square miles. The map site is at about the midpoint of the placer, in the NE1/4 sec. 18, T. 11 S., R. 4 E., of the Copper River Meridian; the location is accurate to within 2000 ft. This site corresponds to loc. P-5 in Jansons and others (1984), which presumably represents both the placer and the lode occurrences.

Geologic setting

Geologic description

The placer occurrence consists of small amounts of gold in alluvial and colluvial gravels derived from underlying metasedimentary rocks of the Upper Cretaceous Valdez Group (Nelson and others, 1985), and from the dunes near the terminus of Heney Glacier (Kodosky and Teller, 1989). A 0.1- cubic-yard sample assayed 0.0006 oz. Au/cubic yard (Jansons and others, 1984). In addition to the placer occurrence, Jansons and others (1984) describe a shear zone in Valdez Group metasedimentary and metavolcanic rocks in this area that contains galena and pyrrhotite. Analysis of a sample from the shear zone contained 0.14% Pb.
Geologic map unit (-144.752021033807, 60.9195063245656)
Mineral deposit model Placer Au (Cox and Singer, 1986; model 39a) and Cyprus massive sulfide (Cox and Singer, 1986; model 24a)
Mineral deposit model number 39a and 24a
Age of mineralization Placer Au is Holocene. Sulfide mineralization is Late Cretaceous or younger, based on the age of the host rocks.

Production and reserves

Workings or exploration Site was sampled as part of a U.S. Bureau of Mines and U.S.G.S. mineral resource assessment of the Chugach National Forest (Jansons and others, 1984; Nelson and others, 1984). The area near the terminus of Heney Glacier was examined by industry in 1988 for placer gold (Kodosky and Teller, 1989).
Indication of production None

Additional comments

Chugach Alaska Corporation, Anchorage, Alaska has control of these lands.

References