Unnamed (on Minnesota Ridge)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Other commodities Au
Ore minerals chalcopyrite; pyrite

Geographic location

Quadrangle map, 1:250,000-scale SK
Quadrangle map, 1:63,360-scale A-4
Latitude 59.01
Longitude -136.27
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of approximately 2,900 feet on Minnesota Ridge in Glacier Bay National Park and Preserve. It is in the NE1/4, section 17, T. 33 S., R. 55 E. of the Copper River Meridian. It is shown as location 5 in Cobb (1972 [MF-424]) and in figure C-66 of Brew and others (1978).

Geologic setting

Geologic description

The following description is summarized from Brew and others (1978).
The northwest portion of Minnesota Ridge consists of locally iron-stained quartz diorite cut by a few andesite dikes. The iron-stained quartz diorite has small amounts of chalcopyrite smeared along tiny fractures. The highest values obtained from nine samples were 490 ppm copper, 30 ppm molybdenum, 0.10 ppm gold, and 0.7 ppm silver. Based on the age of the host intrusion, the mineralization must be Cretaceous or younger in age.
Geologic map unit (-136.271886803329, 59.0095993713308)
Mineral deposit model There is too little information to adequately characterize this occurrence.
Age of mineralization Based on the age of the host intrusion, the mineralization must be Cretaceous or younger in age (Brew, 1978).

Production and reserves

Indication of production None

Additional comments

This is a very low grade occurrence. The deposit is within Glacier Bay National Park and Preserve where exploration and development is restricted.

References