Prospect, Inactive

Commodities and mineralogy

Main commodities Cu
Other commodities Ag; Fe
Ore minerals azurite; bornite; chalcopyrite; magnetite; malachite
Gangue minerals calcite; epidote; quartz

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale B-6
Latitude 63.2678
Longitude -146.7494
Nearby scientific data Find additional scientific data near this location
Location and accuracy A prospect that possibly corresponds to the Snowstrike reportedly is in an east-west drainage on the east side of the West Fork Maclaren River at an elevation of 3,400 feet about 2,000 feet east of the center of section 15, T. 19 S., R. 5 E., Fairbanks Meridian (Kaufman, 1964). Kaufman's location corresponds approximately to locality 14 in figure 4 of Cobb (1979 [OFR 79-238]) and locality 9 of MacKevett and Holloway (1977). Kurtak and others (1992) reported mineralization in this drainage between 3,700 and 4,800 feet (locality A17). The Kardex site number is KX68-193 (Heiner and Porter, 1972).

Geologic setting

Geologic description

The rocks at the prospect are andesitic to basaltic greenstone of possible Triassic age; a narrow dike of quartz hornblende diorite cuts the greenstone about 100 feet below the prospect (Kaufman, 1964, p. 8). Limestone is reported nearby (Saunders, 1961).
Azurite and malachite occur as irregular surface coatings for a distance of about 100 feet on the north side of the east-west creek. These minerals formed from the oxidation of chalcopyrite and bornite in quartz-calcite-epidote veins in fractures that cut greenstone. One set of mineralized fractures strikes north-south and is nearly vertical (Kaufman, 1964). The veins are widely separated and no more than several inches thick. Saunders (1961 [report for 1961]) reported an occurrence of massive magnetite nearby, probably in a limestone host.
Apparently Kurtak and others (1992) prospected vertically above Kaufman's locality. They reported limonite-stained metabasalt on the cirque wall near the top of the canyon. Quartz-rich float boulders contained as much as 0.12 percent copper.
Geologic map unit (-146.751668921287, 63.2673632545963)
Mineral deposit model Copper-bearing veins in intermediate to mafic volcanic rocks. Basaltic Cu (Cox and Singer, 1986; model 23).
Mineral deposit model number 23
Age of mineralization Epigenetic (Mid-Cretaceous?) copper occurrences in Triassic (?) andesite and basalt

Production and reserves

Workings or exploration The area was prospected, and at least one claim (Snowstrike) was located. It was subsequently studied by the State of Alaska (Saunders, 1961 [report for 1961]; Kaufman, 1964) and the U.S. Bureau of Mines (Kurtak and others, 1992).
Indication of production None