Unnamed (northeast of Slate Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite; malachite; secondary copper minerals
Gangue minerals epidote

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale A-2
Latitude 63.1804
Longitude -144.8319
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is south of the terminus of the Chistochina Glacier at an elevation of about 4,600 feet. It is about 1.1 miles northeast of the mouth of Slate Creek and about one-half mile southwest of informally named Big Four Creek, in the NW1/4SW1/4 of sec. 14, T. 20 S., R. 15 E., Fairbanks Meridian. It corresponds to locality 23 of Rose (1967), locality 13 on figure 6 of Cobb (1979 [OFR 79-238]), and locality 135 of Nokleberg and others (1991). The location is probably accurate within 0.2 mile.

Geologic setting

Geologic description

This occurrence is in a body of gabbro and mafic gabbro that is about a mile wide and possibly elongated to the northeast (Rose, 1967). The gabbro is probably Late Triassic in age. The mafic intrusive is overlain unconformably by the 'round wash' conglomerate of Tertiary age. The same gabbro body forms the bedrock in the Big Four Creek placer deposit (MH293). Chalcopyrite and secondary copper minerals, probably including malachite, occur in a vein or in a vuggy epidote-filled segregation in gabbro.
Geologic map unit (-144.834129069564, 63.1800043588989)
Age of mineralization Late Triassic or younger, on the basis of the age of the host rock.
Alteration of deposit Alteration consists of epidote-filled veining or segregations in gabbro.

Production and reserves

Workings or exploration No workings are reported.
Indication of production None