|Quadrangle map, 1:250,000-scale||MC|
|Quadrangle map, 1:63,360-scale||B-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||These prospects are on the south flank of Nikolai Butte at an elevation of about 4,200 feet, 1,700 feet south-southwest of the summit of Nikolai Butte and 1.300 feet south of the center of section 1, T. 6 S., R. 16 E. of the Copper River Meridian. This is locality 58 of MacKevett (1976); the location is accurate to within a few hundred feet.|
Geologic descriptionSeveral small prospects in this area are on thin silver- and base-metal-bearing veins. The veins are localized along steep faults that cut Triassic Nikolai Greenstone and Triassic Chitistone Limestone; they are marked by copper-stained zones along the contact of the greenstone and limestone (MacKevett, 1976). Samples of vein material contained as much as 10 parts per million (ppm) silver, more than 20,000 ppm copper, 15,000 ppm lead, and 10,000 ppm zinc (MacKevett and Smith, 1968, samples 50-52). Surface pits and cuts probably explored these prospects. Copper-bearing mineralization in the Triassic Nikolai Greenstone and Chitistone Limestone is probably Cretaceous in age (MacKevett and others, 1997) but the presence of other base metals in these deposits indicates they could be younger.
|Geologic map unit||(-142.461152203549, 61.37457251943)|
|Mineral deposit model||Polymetallic veins? (Cox and Singer, 1986; model 22c)|
|Mineral deposit model number||22c?|
|Age of mineralization||Cretaceous or Tertiary? Copper-bearing mineralization in the Triassic Nikolai Greenstone and Chitistone Limestone is probably Cretaceous in age (MacKevett and others, 1997) but the presence of other base metals in these deposits indicates they could be younger.|
|Alteration of deposit||Oxidation.|
|Workings or exploration||Surface pits and cuts probably explored these prospects.|
|Indication of production||None|
Additional commentsThe locality is in the Wrangell-Saint Elias National Park and Preserve.
MacKevett, E.M., Jr., 1976, Mineral deposits and occurrences in the McCarthy quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-773-B, 2 sheets, scale 1:250,000.
MacKevett, E.M., Jr., and Smith, J.G., 1968, Distribution of gold, copper, and some other metals in the McCarthy B-4 and B-5 quadrangles, Alaska: U.S. Geological Survey Circular 604, 25 p.
MacKevett, E.M., Jr., and Smith, J.G., 1972, Geologic map of the McCarthy B-4 quadrangle, Alaska: U.S. Geological Survey Geologic Quadrangle Map GQ-943, 1 sheet, scale 1:63,360.
MacKevett, 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.
|Reporters||Travis L. Hudson (Applied Geology, Inc.)|
|Last report date||1/12/2003|