Unnamed (east of Big Lake)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Au; Zn
Ore minerals pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale TK
Quadrangle map, 1:63,360-scale D-3
Latitude 62.9897
Longitude -148.0376
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 3,300 feet, 5 miles east of Big Lake. The occurrence is in the SW1/4 sec. 24, T. 22 S., R. 3 W., Fairbanks Meridian. The location is accurate to within 1/4 mile. This occurrence has also been called the Watana Creek lode. This is locality 13 of Csejtey and Miller (1978).

Geologic setting

Geologic description

This occurrence consists of pyrite in a silicified zone in a Tertiary granitic pluton that intrudes metabasalt and Lower Cretaceous argillite and lithic graywacke (Csejtey and others, 1978). The metabasalt next to the pluton is also silicified. A sample of felsic intrusive rock collected by the U.S. Geological Survey contains 2.5 parts per million gold and 0.5 parts per million silver (Miller and others, 1978). Samples of silicified granite and silicified wall rock collected by the U.S. Bureau of Mines contain up to 0.5 parts per million silver and 0.12 percent zinc; a placer sample contains 1,500 parts per billion gold (Kurtak and others, 1992).
Geologic map unit (-148.039853517655, 62.9892434500157)
Mineral deposit model Porphyry Cu or Polymetallic vein? (Cox and Singer, 1986; model 20c or 22c?)
Mineral deposit model number 20c or 22c?
Alteration of deposit Granite and metabasalt are silicified.

Production and reserves

Workings or exploration Limited sampling by the U.S. Geological Survey and U.S. Bureau of Mines (Miller and others, 1978; Kurtak and others, 1992).
Indication of production None

Additional comments

MAS/MILS number 20760112.

References

MRDS Number A012162

References

Reporters R.K. Rogers (U. S. Geological Survey contractor)
Last report date 10/2/2002