1. Mineral Resources
  2. Online Spatial Data
  3. Alaska Resource Data File (ARDF)

Peacock

Prospect, Inactive

Map
KML
XML
GeoJSON

Commodities and mineralogy

Main commodities Cu
Ore minerals azurite; bornite; chalcocite; malachite; pyrite
Gangue minerals calcite; epidote

Geographic location

Quadrangle map, 1:250,000-scale VA
Quadrangle map, 1:63,360-scale C-1
Latitude 61.6705
Longitude -144.0629
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is on the east side of upper Copper Creek (Van Alstine and Black, 1946, plate 30); it is at an elevation of about 4,100 feet in the NW1/4 section 25, T. 2 S., R. 7 E., of the Copper River Meridian. This prospect is approximately located, perhaps to within one-quarter mile. It is included in locality 70 of Cobb and Matson (1972) and locality 57 of Winkler and others (1981 [OFR 80-892-B]). Cobb (1979 [OFR 79-1241]) includes this prospect under the name 'Peacock'.

Geologic setting

Geologic description

Triassic Nikolai Greenstone contains small, scattered grains and veinlets of bornite, chalcocite, and pyrite; secondary minerals include azurite and malachite (Van Alstine and Black, 1946, p. 130). The veinlets are as much as one inch thick in a 40-foot-long adit. Brecciated greenstone on the surface above the adit is cemented with calcite, epidote, and bornite. Individual calcite-bornite seams in the breccia are as much as 2 inches thick. The copper mineralization is believed to be related to the regional mineralizing event that produced the rich Kennecott copper deposits in the McCarthy quadrangle (MacKevett and others, 1997).
Geologic map unit (-144.064995339601, 61.6700340964412)
Mineral deposit model Vein and fracture fillings in greenstone; probably related to Kennecott-type copper deposits (MacKevett and others, 1997)
Age of mineralization The copper mineralization is believed to be related to the mineralizing event that produced the rich Kennecott copper deposits in the McCarthy quadrangle to the east (MacKevett and others, 1997). This event is interpreted to have accompanied Late Jurassic or Early Cretaceous deformation and metamorphism (MacKevett and others, 1997, p. 88).
Alteration of deposit Calcite and epidote veining and breccia-filling in greenstone.

Production and reserves

Workings or exploration This prospect was explored with an adit that was caved 40 feet from the portal in 1943 (Van Alstine and Black, 1946).
Indication of production None

Additional comments

This prospect is within the Wrangell-St. Elias National Park.

References

MRDS Number A011516

References

Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Valdez quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-1241, 167 p.
Cobb, E.H., and Matson, N.A., Jr., 1972, Metallic mineral resources map of the Valdez quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-438, 1 sheet, scale 1:250,000.
MacKevett, E.M., Jr., Cox, D.P., Potter, R.W., III, and Silberman, M.L., 1997, Kennecott-type deposits in the Wrangell Mountains, Alaska--High-grade copper ores near a basalt-limestone contact, in Goldfarb, R.J., and Miller, L.D., eds., Mineral deposits of Alaska: Economic Geology Monograph 9, p. 66-89.
Van Alstine, R.E., and Black, R.F., 1946, Copper deposits of the Kotsina-Kuskulana district, Alaska: U.S. Geological Survey Bulletin 947-G, p. 121-141.
Winkler, G.R., Miller, R.J., MacKevett, E.M., Jr., and Holloway, C.D., 1981, Map and summary table describing mineral deposits in the Valdez quadrangle, southern Alaska: U.S. Geological Survey Open-File Report 80-892-B, 2 sheets, scale l:250,000.
Reporters Travis L. Hudson
Last report date 12/14/2001