Unnamed (northeast of the head of Quartz Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities Ag. Pb; Zn
Ore minerals galena; gold; pyrite; sphalerite
Gangue minerals carbonate minerals; quartz

Geographic location

Quadrangle map, 1:250,000-scale GU
Quadrangle map, 1:63,360-scale D-1
Latitude 62.8
Longitude -144.02
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is an altered-sulfidized area more than one-mile long and about one-quarter mile across. It trends east-northeast across the ridge that divides Ahtell and Porcupine Creeks, northeast of the head of Quartz Creek. The center of the area is about 1,000 feet west of the center of section 24, T. 12 N., R. 7 E., Copper River Meridian.

Geologic setting

Geologic description

The country rocks are mainly Pennsylvanian to Permian volcanic rocks with lesser sedimentary rocks (Richter, 1966; Richter and Matson, 1968). They have been silicified, converted to silica-carbonate rocks, and locally sulfidized along a east-northeast to northeast trending zone more than one mile long (WGM Inc., 1980). A soil sample collected in approximately the center of the zone contained more than 500 ppb gold. Rock samples collected from the altered zone locally contained more than 2,000 ppb gold, 20 ppm silver, and 5,000 ppm lead and zinc (Bull, Freeman, and Schneider, 1999).
Geologic map unit (-144.022193205402, 62.7996109900708)
Mineral deposit model Gold porphyry
Age of mineralization Possibly related to a nearby Jurassic diorite intrusion.
Alteration of deposit Silicification; formation of silica-carbonate rock in intermediate volcanics; local sulfidation.

Production and reserves

Workings or exploration Only reconnaissance mapping and sampling of natural exposures.
Indication of production None

Additional comments

Additional information can be obtained from Ahtna Minerals in Anchorage, Alaska.

References

MRDS Number 10307481

References

Bull, Katharine, Freeman, Larry, and Schneider, Craig, 1999, Slana property summary report for Homestake Mining Company: 11 p., analytical appendices. (Report held by Ahtna Minerals Co., Anchorage, Alaska).
WGM Inc., 1980, 1979 Summary report of gold potential, Slana District, Ahtna project: WGM Inc., 10 p., map, scale 1:63,360. (Report held by Ahtna Mineral Co., Anchorage, Alaska).
Reporters W.T. Ellis (Alaska Earth Sciences), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (U.S. Geological Survey)
Last report date 12/8/2000