Main commodities | Cu |
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Ore minerals | chalcopyrite; pyrite |
Quadrangle map, 1:250,000-scale | NB |
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Quadrangle map, 1:63,360-scale | A-4 |
Latitude | 62.1283 |
Longitude | -142.9363 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | This occurrence is on the east nose of a low ridge along the north side of a west tributary stream to lower Nabesna Glacier. It is at an elevation of about 3,800 feet, 2,500 feet west of the glacier and about 1.6 miles east-southeast of elevation 5370. The site is in the NE1/4 of section 13, T. 4 N., R. 13 E. of the Copper River Meridian. This is locality 11 of Richter (1973), locality 21 of Richter and others (1975), and National Park Service locality WRST-29 (unpublished data). Cobb and Richter (1980) included this locality as an 'Unnamed occurrence'. It is located to within a few hundred feet. |
Geologic descriptionSmall irregular masses of pyrite and minor chalcopyrite occur in contact-metamorphosed Triassic, Nikolai Greenstone. A chip sample of pyrite-bearing greenstone contained 500 parts per million (ppm) copper, more than 100 ppm scandium, 200 ppm nickel, and 300 ppm chromium (Richter and Matson, 1970 [OFR 70-276]). This occurrence is in the contact zone of a diorite stock that is inferred to be a border phase of the mid-Cretaceous Nabesna pluton (Richter, 1973). | |
Geologic map unit | (-142.938423608594, 62.1279033852809) |
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Mineral deposit model | Contact metamorphic copper deposit |
Age of mineralization | Mid-Cretaceous? The nearby diorite stock is inferred to be a border phase of the mid-Cretaceous Nabesna pluton (Richter, 1973). |
Alteration of deposit | Tactite development in contact metamorphosed greenstone. |
Indication of production | None |
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Additional commentsThe occurrence is in the Wrangell-St. Elias National Preserve. |
MRDS Number | A011394 |
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References | |
Reporters | Travis L. Hudson (Applied Geology) |
Last report date | 11/24/2002 |