Unnamed (west of lower Canwell Glacier)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Au; Cu
Ore minerals arsenopyrite; chalcopyrite; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale B-4
Latitude 63.3266
Longitude -145.5916
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of 4,800 on the west valley wall of lower Canwell Glacier. It is one-quarter mile due west of the center of section 26, T. 18 S., R. 11 E., Fairbanks Meridian. This record combines the description of the occurrence by Hanson (1963, p. 72) with that of locality S116 of table 2 in Nokelberg and others (1991).

Geologic setting

Geologic description

Hanson (1963) described this location as pyrite- and arsenopyrite-bearing silicified granodiorite. Nokleberg and others (1991) described it as a 25- by 50-foot silicified zone of chalcopyrite- and pyrite-bearing quartz veins in fractures in silicified mid-Cretaceous quartz diorite. W.T. Ellis (oral communication, 1996) described the host rock as quartz monzonite that grades into quartz diorite where it intrudes the Canwell mafic-ultramafic sill of Late Triassic age.
An American Copper and Nickel Company sample of silicified and iron-stained quartz monzonite contained 1,030 parts per million (ppm) copper (W.T. Ellis, oral communication, 1996). A grab sample of the 25- by 50-foot silicified zone contained 12,000 ppm copper, 30 ppm silver, and 0.10 ppm gold (Nokleberg and others, 1991).
Geologic map unit (-145.593849485147, 63.3261895478226)
Mineral deposit model Porphyry Cu (Cox and Singer, 1986; model 17).
Mineral deposit model number 17
Age of mineralization Probably mid-Cretaceous.
Alteration of deposit The granitic host rocks are variably silicified; iron sulfide minerals are oxidized.

Production and reserves

Workings or exploration An American Copper and Nickel Company sample of silicified and iron-stained quartz monzonite contained 1,030 parts per million (ppm) copper (W.T. Ellis, oral communication, 1996). A grab sample of the 25- by 50-foot silicified zone contained 12,000 ppm copper, 30 ppm silver, and 0.10 ppm gold (Nokleberg and others, 1991).
Indication of production None

References