Upper Crooked Creek

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au
Ore minerals gold
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale BN
Quadrangle map, 1:63,360-scale A-4
Latitude 65.03
Longitude -163.75
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is on the divide between the headwaters of Virginia Creek, Oxide Creek, Crooked Creek (BN102), and Albion Creek (BN103). It is very approximately located at an elevation of 900 feet; probably located within one mile. This is locality 12 of Cobb (1972; MF 417; 1975; OFR 75-429).

Geologic setting

Geologic description

A gold-bearing lode that consists of quartz veins containing up to 2 ounces Au per ton, occurs on the divide between Goldbottom and Crooked Creeks; it is reported to be near a marble-schist contact (Collier and others, 1908) and to be similar to an occurrence near the mouth of Crooked Creek (BN100; Smith and Eakin, 1911). The occurrence near the mouth of Crooked Creek is a 12-foot wide mineralized zone in schistose limestone (marble) that contains quartz veins and pyrite. Bedrock in the area of this occurrence is metasedimentary schist and marble of a lower Paleozoic assemblage (Till and others, 1986).
Geologic map unit (-163.752626406063, 65.0292736581006)
Mineral deposit model Gold-bearing quartz veins in schistose marble
Age of mineralization Possibly mid-Cretaceous; if gold-bearing lode structures are present here they may be similar in age to some lode gold deposits of southern Seward Peninsula. The southern Seward Peninsula lode gold deposits formed as a result of mid-Cretaceous metamorphism (Apodoca, 1994; Ford, 1993, Ford and Snee, 1996; Goldfarb and others, 1997) that accompanied regional extension (Miller and Hudson, 1991) and crustal melting (Hudson, 1994). This higher temperature metamorphism was superimposed on high pressure/low temperature metamorphic rocks of the region.
Alteration of deposit Quartz veining and possibly disseminated pyrite is present in the metasedimentary host rocks.

Production and reserves

Workings or exploration Some small surface prospecting pits are probably present.
Indication of production None

References

MRDS Number A012760

References

Apodoca, L.E., 1994, Genesis of lode gold deposits of the Rock Creek area, Nome mining district, Seward Peninsula, Alaska: Boulder, Colorado, University of Colorado, Ph.D. dissertation, 208 p.
Ford, R.C., 1993, Geology, geochemistry, and age of gold lodes at Bluff and Mt. Distin, Seward Peninsula, Alaska: Golden, Colorado School of Mines, Ph.D. dissertation, 302 p.
Ford, R.C., and Snee, L.W., 1996, 40Ar/39Ar thermochronology of white mica from the Nome district, Alaska--The first ages of lode sources to placer gold deposits in the Seward Peninsula: Economic Geology, v. 91, p. 213-220.
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.
Hudson, T.L., 1994, Crustal melting events in Alaska, in Plafker, G., and Berg, H. C., eds., The Geology of Alaska: Geological Society of America, DNAG, The Geology of North America, Vol. G-1, p. 657-670.
Reporters Travis L. Hudson (Applied Geology)
Last report date 3/15/1999