| Quadrangle map, 1:250,000-scale | VA |
|---|---|
| Quadrangle map, 1:63,360-scale | C-1 |
| Latitude | 61.6532 |
| Longitude | -144.1263 |
| Nearby scientific data | Find additional scientific data near this location |
| Location and accuracy | These prospects are located east of Deception Creek on the north side of Elliott Creek valley; they are at an elevation of about 4,100 feet in the NW1/4 section 34, T. 2 S., R. 7 E., of the Copper River Meridian. The prospects are approximately located, perhaps to within one-half mile. They are incuded in locality 64 of Cobb and Matson (1972) and locality 54 of Winkler and others (1981 [OFR 80-892-B]). |
Geologic descriptionThese prospects are near the Albert Johnson prospect (VA034) north of the headwaters of Elliott Creek. At the Albert Johnson prospect, bornite, chalcopyrite, and some native copper occur in small sheeted veins and replacement deposits in fractured Triassic Nikolai Greenstone (Mendenhall and Schrader, 1903; Moffit, 1918, p. 156-157). In general, thin veins, films and disseminations of bornite, chalcocite, and pyrite cut Triassic Nikolai Greenstone in this area (Moffit and Maddren, 1908 ,1909; Moffit and Mertie, 1923). Gangue minerals are commonly quartz, calcite, and epidote; secondary copper minerals include malachite, azurite and some chalcanthite. Some mineralization occurs as irregular pods in greenstone. The Nikolai Greenstone and overlying Chitistone Limestone are deformed into a large, asymmetric anticline with its axis approximately parallel to Elliott Creek. The copper mineralization is believed to be related to the regional mineralizing event that produced the rich Kennecott copper deposits in the McCarthy quadrangle (MacKevett and others, 1997). | |
| Geologic map unit | (-144.128395534629, 61.6527325850821) |
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| Mineral deposit model | Veins, disseminations, and fracture fillings in greenstone; probably related to Kennecott-type copper deposits (MacKevett and others, 1997) |
| Age of mineralization | The copper mineralization is believed to be related to the mineralizing event that produced the rich Kennecott copper deposits in the McCarthy quadrangle to the east (MacKevett and others, 1997). This event is interpreted to have accompanied Late Jurassic or Early Cretaceous deformation and metamorphism (MacKevett and others 1997, p. 88). |
| Workings or exploration | These prospects were mostly explored with open cuts (Moffit and Mertie, 1923). |
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| Indication of production | None |
Additional commentsThis prospect is within the Wrangell-St. Elias National Park. | |
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 Goldfarb, R.J., and Miller, L.D., eds., Mineral deposits of Alaska: Economic Geology Monograph 9, p. 66-89.
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| Reporters | Travis L. Hudson |
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| Last report date | 12/14/2001 |