National mineral assessment tract AK-AP08 (Low-sulfide Au-quartz veins, Chugach type)

Tract AK-AP08
Geographic region AK Peninsula & Aleutian Is.
Tract area 1,467sq km
Deposit type Low-sulfide Au-quartz veins, Chugach type
Deposit age Tertiary

Rationale

Explained by Frederic H. Wilson, Stanley E. Church, Richard W. Saltus, Lawrence J. Drew, and W. David Menzie.
On the choice of deposit models
This tract is considered permissive for Chugach-type low-sulfide Au-quartz veins because it is adjacent to a geologically similar tract containing several occurrences of such veins. No gold occurrences are known in this tract.
On the delineation of permissive tracts
This tract comprises rocks of the Ghost Rocks, Sitkalidak, Sitkinak, and other Tertiary Formations on the southeast and east side of the Kodiak Islands (Moore, 1967, 1969). These formations consist of a variety of lithologies, including flysch and marine sandstone and siltstone, and possibly ultramafic rocks. Parts of this tract are tentatively correlated with the Orca Group of Prince William Sound.
Important examples of this type of deposit
No gold occurrences are known in this tract.
On the numerical estimates made
No estimate of the number of undiscovered Chugach-type low-sulfide Au-quartz deposits has been attempted because of the lack of relevant geologic data.
References
Moore, G.W., 1967, Preliminary geologic map of Kodiak Island and vicinity, Alaska: U.S. Geological Survey Open‑file Map 271, scale 1:250,000.
Moore, G.W., 1969, New formations on Kodiak and adjacent islands, Alaska: U.S. Geological Survey Bulletin 1274‑A, p. A27‑A35.

Geographic coverage

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