| Quadrangle map, 1:250,000-scale | MC |
|---|---|
| Quadrangle map, 1:63,360-scale | B-5 |
| Latitude | 61.4978 |
| Longitude | -142.7748 |
| Nearby scientific data | Find additional scientific data near this location |
| Location and accuracy | This prospect is on the east valley wall of McCarthy Creek on the north flank of Green Butte. It is at an elevation of about 3,600 feet, 2,400 feet west of elevation 5720 near the northwest corner of section 30, T. 4 S., R. 15 E. of the Copper River Meridian. The prospect is shown as quarry symbol on the McCarthy B-5 quadrangle (1994 edition). This is locality 88 of MacKevett (1976) and it is accurately located. Cobb and MacKevett (1980) included this prospect under the name 'Tjosevig'. |
Geologic descriptionThe deposit at this prospect consists of malachite and azurite that forms thin films and veinlets along fractures in the lower part of the Triassic Chitistone Limestone (Miller, 1946; MacKevett, 1976). Eight claims were patented in 1928 and the deposits were explored by a short adit that was caved near the portal by 1943 (Miller, 1946). Copper mineralization is widespread in Chitistone Limestone and is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic to Early Cretaceous (MacKevett and others, 1997). | |
| Geologic map unit | (-142.776878133579, 61.4973646076873) |
|---|---|
| Mineral deposit model | Kennecott-type copper deposit (after MacKevett and others, 1997) |
| Age of mineralization | Cretaceous? Copper mineralization is widespread in Chitistone Limestone and is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic to Early Cretaceous (MacKevett and others, 1997). |
| Alteration of deposit | Oxidation. |
| Workings or exploration | Eight claims were patented in 1928 and the deposits were explored by a short adit that was caved near the portal by 1943 (Miller, 1946). |
|---|---|
| Indication of production | None |
Additional commentsThe locality is in the Wrangell-Saint Elias National Park and Preserve. | |
| MRDS Number | A011718 |
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ReferencesMacKevett, E. M., Jr., Cox, D. P., Potter, R. W., III, and Silberman, M. L., 1997, Kennecott-type deposits in the Wrangell Mountains, Alaska: High-grade copper ores near a basalt-limestone contact, in, Miller, L. D., and Goldfarb, R.J., eds., Mineral deposits of Alaska: Economic Geology Monograph 9, p. 66-89.
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| Reporters | Travis L. Hudson (Applied Geology, Inc.) |
| Last report date | 1/12/2003 |