Porphyry copper prospect in Alaska, United States

Names and other identifiers

Tract name Eastern Alaska Range and Wrangell Mountains (003pCu5002)
Site status prospect

Geographic location

Country United States
State or province Alaska
Geographic location -144.17, 62.8
Geologic map unit -144.17, 62.8
Nearby data

Geologic information

Deposit type Porphyry copper
Age determination method Geologic inference
Age range Pennsylvanian–Permian (Emplaced subseqent to or is related to the border phase of the Ahtell pluton.)
Age reference Richter (1966)
Minerals chalcopyrite, fluorite, ferrimolybdate, molybdenite, pyrite
Tectonic setting continental margin
Stratigraphic age Pennsylvanian–Permian

Commodity and development information

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

Reference information

Comments Low-grade, molybdenum porphyry occurs in a complex contact region of the Pennsylvanian- to Permian-age Ahtell pluton; mostly in the Border phase and in the overlying volcanic rocks of the Pennsylvanian- to Permian-age Slana Spur Formation. Argillic and sericite alteration; argillic alteration is probably accentuated by supergene acid solutions formed by oxidation of pyrite. Discovered in 1957, but no work was done until 1968; drilling in 1968 and 1969 showed that most of the deposit is very lowgrade, but two shallow holes intercepted rich mineralization.
Study area name United States
References U.S. Geological Survey (2014a); Richter (1966)
Site reference U.S. Geological Survey National Mineral Resource Assessment Team (2002)