|Quadrangle map, 1:250,000-scale||MH|
|Quadrangle map, 1:63,360-scale||A-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The occurrence is at an elevation of 4,100 feet in a small cirque west-northwest of Lower Tangle Lake. It is in the SE1/4SW1/4 section 27, T. 20 S., R. 9 E., Fairbanks Meridian. This location corresponds to locality S75 in table 2 of Nokleberg and others (1991), locality 9 of Cobb (1979 [OFR 79-238]), and an occurrence described by Stout (1976, p. 30 and plate 1).|
This occurrence includes two types of deposits. One consists of pods as much as a foot thick of massive chalcopyrite and bornite in metabasalt of Nikolai Greenstone of Late Triassic age (Stout, 1976). The other consists of chalcopyrite, bornite, and copper oxide-bearing quartz veins in north-northeast-striking joints in the greenstone. Malachite-coated copper nuggets occur in stream gravels in a nearby cirque.The quartz veins are localized in north-northeast-trending joints that cut across the folded limbs of the Amphitheater syncline. The veins post-date late Jurassic deformation and are probably either Cretaceous related to regional metamorphism and granitic plutonism (Nokleberg and others, 1986) or early Tertiary (Stout, 1976).
|Geologic map unit||(-146.000145685583, 63.1463762323776)|
|Mineral deposit model||Basaltic Cu (Cox and Singer, 1986; model 23).|
|Mineral deposit model number||23|
|Age of mineralization||Late Triassic and Cretaceous.|
|Indication of production||None|
Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Mount Hayes quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-238, 140 p.
Nokleberg, W.J., Lange, I.M., Roback, R.C., Yeend, Warren, and Silva, S.R., 1991, Map showing locations of metalliferous lode and placer mineral occurrences, mineral deposits, prospects, and mines, Mount Hayes quadrangle, eastern Alaska Range, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1996-C, 42 p., 1 sheet, scale 1:250,000.
|Reporters||W.T. Ellis (Alaska Earth Science), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (USGS)|
|Last report date||6/17/2002|