Unnamed (west of Twelvemile Canyon)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Au
Ore minerals gold

Geographic location

Quadrangle map, 1:250,000-scale MC
Quadrangle map, 1:63,360-scale A-8
Latitude 61.0271
Longitude -143.9597
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is in the headwaters of an unnamed tributary to the North Fork of the Bremner River. It is at an elevation of about 4,500 feet, 3,500 feet northeast of VABM Sob on peak 6341. The occurrence is in the SE1/4 of section 3, T. 10 S., R. 8 E. of the Copper River Meridian. This is locality 12 of MacKevett (1976); the location is accurate to within about 1,000 feet.

Geologic setting

Geologic description

This occurrence consists of thin quartz veins that cut Cretaceous Valdez Group flysch. A sample of the quartz veins contained 7 parts per million silver and some are probably gold-bearing (MacKevett, 1976). Gold-bearing quartz veins in the Valdez Group are generally Early Tertiary in age (Goldfarb and others, 1997).
Geologic map unit (-143.961740806768, 61.0266301907429)
Mineral deposit model Low sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)
Mineral deposit model number 36a
Age of mineralization Early Tertiary. Gold-bearing quartz veins in the Valdez Group are generally Early Tertiary in age (Goldfarb and others, 1997).
Alteration of deposit Silicification.

Production and reserves

Indication of production None

Additional comments

The locality is in the Wrangell-Saint Elias National Park and Preserve.

References

References

Goldfarb, R.J., Miller, L.D., Leach, D.L., and Snee, L.W, 1997, Gold deposits in metamorphic rocks in Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 151-190.
Reporters Travis L. Hudson (Applied Geology, Inc.)
Last report date 1/12/2003