Mike

Porphyry copper prospect in Alaska, United States

Names and other identifiers

GMRAP ID 3426
Tract name Alaska Peninsula and Aleutian Islands (003pCu5006)
Site status prospect

Geographic location

Country United States
State or province Alaska
Geographic location -157.235, 57.054
Geologic map unit -157.235, 57.054
Nearby data

Geologic information

Deposit type Porphyry copper
Age determination method Geologic inference
Age range Pliocene or younger (Inferred from age of intrusives.)
Age reference Wilson and Shew (1982)
Minerals chalcopyrite, galena, hematite, magnetite, molybdenite, pyrite, sphalerite
Tectonic setting mixed
Stratigraphic age Pliocene or younger

Commodity and development information

Development status Prospect
Major commodities Mo
Minor commodities Cu, Pb, Zn
Gold-Moly ratio -9999

Reference information

Comments Originally identified in 1975 on the basis of the color anomaly and a stream-sediment survey showing a large copper-molybdenum anomaly. The area consists of dikes, sills, and stocks which have intruded sandstones of the Jurassic-age Naknek Formation. The main area of mineralization occurs in a zone of silica flooding around and within a rhyolite porphyry stock; the silica-flooded zone in the rhyolite stock is in part surrounded and overlapped by intense sericitic and phyllic alteration; beyond this zone the rocks have been propylized. Detailed mapping and sampling and drilling in 1977.
Study area name United States
References U.S. Geological Survey (2014a); Church and others (1989); Wilson and Shew (1982)
Site reference U.S. Geological Survey National Mineral Resource Assessment Team (2002)