Unnamed (west of upper Getmuna Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ni; Zn
Other commodities Bi; Co; Cr
Ore minerals unspecified sulfides
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale SM
Quadrangle map, 1:63,360-scale D-7
Latitude 61.78842
Longitude -158.5958
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is on a north-northeast trending ridge separating the headwaters of Getmuna Creek on the east from tributaries of the Kolmakof River on the west. It is near hill 1666, about 0.4 mile south of the center of section 30, T. 20 N., R. 51 W., of the Seward Meridian. The location is accurate.

Geologic setting

Geologic description

This occurrence consists of quartz-bearing ferricrete breccia in vitreous mafic volcanic flows of the Upper Cretaceous, Horn Mountains volcanic rocks (Bundtzen and others, 1998). The mineralized zone trends north-south for a distance of about 1,100 feet. One grab sample of the ferricrete breccia contained 610 parts per million (ppm) zinc, 210 ppm nickel, 1,000 ppm chromium, 45 ppm cobalt, and 22 ppm bismuth (Bundtzen and others, 1998). The elevated zinc and bismuth values are probably hydrothermal in origin whereas the high chromium, nickel, and cobalt values probably represent background in the mafic-volcanic host rocks.
Geologic map unit (-158.598179523482, 61.7877144975543)
Mineral deposit model Polymetallic vein (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c
Age of mineralization Undated; may be related to the nearby Horn Mountain pluton which has been dated at 68-69 Ma (Bundtzen and others, 1998).

Production and reserves

Workings or exploration Surface sampling was conducted in 1992 by the Alaska Division of Geological and Geophysical Surveys (Bundtzen and others, 1998).
Indication of production None

References