Main commodities | Cu |
---|---|
Other commodities | Ag; Zn |
Ore minerals | chalcopyrite; pyrite |
Quadrangle map, 1:250,000-scale | LC |
---|---|
Quadrangle map, 1:63,360-scale | B-4 |
Latitude | 60.34 |
Longitude | -154.38 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | Nearly 5.0 km N-NW of Kijik Lake. Locality 17 of Nelson and others (1985) and locality 25 of MacKevett and Holloway (1977). Sec. 18, T. 3 N., R. 29 W., of the Seward Meridian. Locality accurate within 1.6 km. |
Geologic descriptionThe anomaly occurs in a structural zone where biotitic, chloritic, and strong silicic altered dacite porphyry and breccia have been mineralized by 1 percent to 3 percent pyrite and traces of chalcopyrite (?) (Nelson and others, 1983; unit Tv). Mineralization spreads out along a NW-SE fault; possible breccia pipe or intrusive plug localized by the NW-SE fault. Analysis of rock sample yielded 5.8 ppm Ag, 180 ppm Cu, and 275 ppm Zn. Potassium-argon ages for this unit (Tv) range from 56.2 to 62.7 m.y. indicating a Tertiary age for these rocks (Eakins and others, 1978). | |
Geologic map unit | (-154.382221521391, 60.3393316553351) |
---|---|
Mineral deposit model | Porphyry Cu? (Cox and Singer, 1986; model 17?). |
Mineral deposit model number | 17? |
Age of mineralization | Tertiary or younger; potassium-argon ages for the volcanic rocks range from 56.2 to 62.7 m.y. (Eakins and others, 1978). |
Alteration of deposit | Biotite, chloritic, and strong silicic alteration of the dacite. |
Workings or exploration | Analysis of rock sample yielded 5.8 ppm Ag, 180 ppm Cu, and 275 ppm Zn. |
---|---|
Indication of production | None |
Reserve estimates | No reserves |
Production notes | No production |
Additional commentsOverall, anomaly is weak. This may also be locality 2 of Mackevett and Holloway (1977) which corresponds with the Thompson prospects, 2 and 3, of Cobb (1972). Site is in Lake Clark National Park and Preserve. |
MRDS Number | A013028 |
---|---|
ReferencesResource Associates of Alaska, Inc., 1976, Geology and geochemistry of certain land within the Lake Clark National Park: Contract report for U.S. Bureau of Mines, Contract JO166108, 7 v.
| |
Reporters | M.L. Miller (USGS); D.P. Bickerstaff (USGS) |
Last report date | 6/15/1998 |