Unnamed (north of Boulder Creek

Occurrence, Inactive

Alternative names

near hill 1293)

Commodities and mineralogy

Main commodities Au
Other commodities As; Pb; Zn
Ore minerals arsenopyrite
Gangue minerals albite; quartz

Geographic location

Quadrangle map, 1:250,000-scale NM
Quadrangle map, 1:63,360-scale C-2
Latitude 64.6634
Longitude -165.5169
Nearby scientific data Find additional scientific data near this location
Location and accuracy The occurrence is about 500 feet south-southwest of hill 1293 near the center of section 32, T. 9 S., R. 34 W., Kateel River Meridian. It is on the ridge crest about a half-mile north of Twin Mountain Creek (shown as Twin Mtn Ck on the map). The location is accurate within about 500 feet.

Geologic setting

Geologic description

Mineralized schist crops out south of hill 1293 on the ridge crest northwest of the Twin Mountain Creek prospect (NM166). The occurrence was found as a result of a soil geochemistry survey of the Boulder-Twin Mountain Creek area by Kennecott Exploration Company in 1992. The soil survey grid consisted of north-trending lines 1,000 feet apart and east-trending lines 2,000 feet apart. Soils were collected on 200-foot centers (Hawley Resource Group for Kennecott Exploration Company, written communication, 1992). Soils near this occurrence were strongly anomalous in gold, arsenic, lead, and zinc. Rock samples at the occurrence contained as much as 0.1 ounce of gold per ton and more than 1 percent arsenic. The occurrence is within an area about 400 by 400 feet where soils contain as much as 780 ppm lead, 580 ppm zinc, more than 1,000 ppm arsenic, and more than 100 ppb gold. The occurrence is in an anomalous area along the Twin Mountain-Rodine fault. Country rock at the site is west-dipping calcareous metaturbidite (Bundtzen and others, 1994). The site is moderately oxidized. Galena and sphalerite were not found but probably were present before oxidation.
Geologic map unit (-165.519510644549, 64.6626333316341)
Mineral deposit model Low-sulfide Au-quartz veins? (Cox and Singer, 1986; model 36a).
Mineral deposit model number 36a?
Age of mineralization Mid-Cretaceous; postdates regional metmorphism and may be similar in age to low-sulfide gold-quartz veins of the Nome district (see, for example, the Divide prospect, NM058).
Alteration of deposit Sulfidation and albitization of schist near the occurrence.

Production and reserves

Workings or exploration The occurrence was found during follow-up of a soil geochemistry survey conducted for Kennecott Exploration Company in 1992.
Indication of production None

References