Unnamed (east edge of Woodworth Glacier)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale CV
Quadrangle map, 1:63,360-scale D-4
Latitude 60.94
Longitude -145.42
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of 2600 feet at the east edge of Woodworth Glacier. It is in the NW1/4 sec. 4, T. 11 S., R. 1 W., of the Copper River Meridian. The location of the site is accurate to within 2000 ft. The occurrence is shown as site C-13 in Jansons and others (1984).

Geologic setting

Geologic description

The country rocks at this occurrence are metavolcanic rocks (greenstone) and metasedimentary rocks of the Upper Cretaceous Valdez Group. These rocks are part of a 65-mile-long belt of volcanic rocks having potential for volcanogenic massive sulfide deposits, extending to the Copper River (Nelson and others, 1984; 1985). The occurrence consists of small amounts of chalcopyrite in quartz veinlets in two shear zones in the greenstone. The shear zones are 1 to 4 feet wide. Three grab samples contained 0.12% to 1.02% Cu (Jansons and others, 1984).
Geologic map unit (-145.421996025703, 60.9394807629372)
Mineral deposit model Cyprus massive sulfide (Cox and Singer, 1986; model 24a)
Mineral deposit model number 24a
Age of mineralization Late Cretaceous 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).
Three grab samples contained 0.12% to 1.02% Cu (Jansons and others, 1984).
Indication of production None

Additional comments

Crowe and others (1992; 1993) and Sainsbury (1993) discuss the genesis of the volcanogenic massive sulfide deposits in this area. Occurrence is on State of Alaska land.

References

MRDS Number 10307381

References

Sainsbury, C.L., 1993, Geology and geochemistry of volcanogenic massive sulfide deposits and related igneous rocks, Prince William Sound, south-central Alaska, A discussion: Economic Geology, v. 88, p. 1284-1285.
Reporters S.W. Nelson, Anchorage, AK
Last report date 6/10/2000