Albert Johnson

Prospect, Inactive

Commodities and mineralogy

Main commodities Cu
Other commodities Ag
Ore minerals bornite; chalcopyrite; native copper
Gangue minerals calcite; epidote; quartz

Geographic location

Quadrangle map, 1:250,000-scale VA
Quadrangle map, 1:63,360-scale C-1
Latitude 61.6532
Longitude -144.1263
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is located east of Deception Creek on the north side of Elliott Creek; it is at an elevation of about 4,100 feet in the NW1/4 section 34, T. 2 S., R. 7 E., of the Copper River Meridian. This prospect is approximately located, perhaps to within one-half mile. It is included in locality 64 of Cobb and Matson (1972) and locality 54 of Winkler and others (1981 [OFR 80-892-B]). Moffit and Mertie (1923) show this prospect as locality 19 on their plate 3. Cobb (1979 [OFR 79-1241]) incuded it under the name 'Elliot Cr.'.

Geologic setting

Geologic description

Bornite, chalcopyrite, and some native copper occur in small, sheeted veins and replacement deposits in fractured Triassic Nikolai Greenstone (Moffit, 1918, p. 156-157). By 1916, the deposit had been explored by two adits, one 1,076 feet long, and smaller cross cuts. The gangue minerals are commonly quartz, calcite and epidote. The Nikolai Greenstone and overlying Chitistone Limestone are deformed into a large, asymmetric anticline with its axis approximately parallel to Elliot Creek. The copper mineralization is believed to be related to the regional mineralizing event that produced the rich Kennecott copper deposits in the McCarthy quadrangle (MacKevett and others, 1997).
Geologic map unit (-144.128395534629, 61.6527325850821)
Mineral deposit model Thin veins, impregnations, and fracture fillings in greenstone; probably related to Kennecott-type copper deposits (Mackevett and others, 1997)
Age of mineralization The copper mineralization is probably related to the mineralizing event that produced the rich Kennecott copper deposits in the McCarthy quadrangle to the east (MacKevett and others, 1997). This event is interpreted to have accompanied Late Jurassic or Early Cretaceous deformation and metamorphism (MacKevett and others 1997, p. 88).

Production and reserves

Workings or exploration By 1916, the deposit had been explored by two adits, one 1,076 feet long, and smaller cross cuts (Moffit, 1918).
Indication of production None

Additional comments

This prospect is within the Wrangell-St. Elias National Park.

References