Unnamed (tributary to Trail Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities Ag; As; B; Bi; Sb; Zn
Ore minerals arsenopyrite; pyrite
Gangue minerals clay; quartz; tourmaline

Geographic location

Quadrangle map, 1:250,000-scale GO
Quadrangle map, 1:63,360-scale D-3
Latitude 59.94
Longitude -159.89
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is in an unnamed west tributary to Trail Creek, about 7 miles northeast of Kagati Lake and 2 miles north of the Kagati Lake prospect (GO011). The map site is at an elevation of about 1,800 feet in the SW1/4 of section 2, T 3 S, R 62 W, of the Seward Meridian. It is area 3 of Kilburn and others (1992), and is approximately located, perhaps within 1 mile.

Geologic setting

Geologic description

This occurrence is in hornfels near the contact of an Upper Cretaceous granitic stock (Hoare and Coonrad, 1978). Reconnaissance stream-sediment and pan concentrate samples from the area contain anomalous levels of several elements (Kilburn and Jones, 1992; Jones and Kilburn, 1992). Silicified hornfels contains disseminated pyrite and pyrite-, arsenopyrite-, and tourmaline-bearing quartz veins. Clay alteration and weakly disseminated pyrite characterize some iron-stained outcrops. Rock samples of altered and mineralized hornfels contain up to 0.28 ppm Ag, greater than 3,800 ppm As, 0.15 ppm Au, greater than 2,000 ppm B, 11 ppm Bi, greater than 5,000 ppm Mn, 5.4 ppm Sb, and 230 ppm Zn (Kilburn and others, 1992).
Geologic map unit (-159.892238314547, 59.9392517197488)
Mineral deposit model Polymetallic veins (Cox and Singer, 1986; model 22c)
Mineral deposit model number 22c
Age of mineralization Late Cretaceous. The mineralization is assumed to be related to the Upper Cretaceous granitic stock, which yielded a K/Ar age of 71.1 +/- 2.1 Ma on biotite (Hoare and Coonrad, 1978).
Alteration of deposit Silicification, clay alteration, and oxidation.

Production and reserves

Workings or exploration Only reconnaissance surface observations and sampling have been completed in the area.
Indication of production None