Unnamed (near head of Kobuk River)

Occurrences, Inactive

Commodities and mineralogy

Main commodities Sn; W; Zn
Other commodities Be; Bi

Geographic location

Quadrangle map, 1:250,000-scale SP
Quadrangle map, 1:63,360-scale B-3
Latitude 67.31
Longitude -154.02
Nearby scientific data Find additional scientific data near this location
Location and accuracy This site represents two occurrences in a north-trneding, mile-long area near the head of the Kobuk River. The center of the area is in the N1/2 of sec. 17, T. 22 N., R. 22 E., of the Kateel River Meridian. The location is accurate to within 2000 ft. The site corresponds to localities 53 and 54 of Grybeck and Nelson (1981).

Geologic setting

Geologic description

The occurrences consist of small skarn deposits adjacent to Devonian granite and Paleozoic metamorphic rocks (Nelson and Grybeck, 1980). Selected float samples contain 200 ppm Be, 200 to 500 ppm Bi, 500 ppm W, 1000 ppm Sn, and 500 to 2000 ppm Zn. The occurrences are similar to other skarn deposits in the Brooks Range (Newberry and others, 1986).
Geologic map unit (-154.022799397853, 67.3095041893985)
Mineral deposit model Skarn (Cox and Singer, 1986; model 14b)
Mineral deposit model number 14b
Age of mineralization Devonian; related to the intrusion of Devonian pluton.
Alteration of deposit Calc-silicate minerals.

Production and reserves

Indication of production None

Additional comments

Located within Gates of the Arctic National Park.


MRDS Number 10308336


Reporters S.W. Nelson (Anchorage, Alaska)
Last report date 9/21/1999