|Quadrangle map, 1:250,000-scale||MH|
|Quadrangle map, 1:63,360-scale||A-6|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is at an elevation of about 5,500 feet about midway between Clearwater Creek and the West Fork Maclaren River. The map site is near the top of the ridge about 0.4 mile west-northwest of VABM Little in section 15, T. 20 S., R. 5 E., Fairbanks Meridian. The occurrence corresponds to locality 8 in figure 4 of Cobb (1979 [OFR 79-238]) and to locality 15 in table 2 of Nokleberg and others (1991). The location is probably accurate within one-third mile.|
Geologic descriptionThe country rock at this occurrence is basalt of the Nikolai Greenstone of Late Triassic age (Nokleberg and others, 1991). The mineral deposit is a vein in propylitically altered greenstone. A quartz-epidote vein in an approximately 9-foot-wide shear zone contains bornite, chalcocite, and malachite. Sample 79IL031A of vein material assayed 2.4 percent copper, 15 parts per million (ppm) silver, and 0.1 ppm gold (Nokleberg and others, 1991, locality 15).
|Geologic map unit||(-146.832466842746, 63.2140601842772)|
|Mineral deposit model||Copper-bearing vein in weakly cupriferous greenstone. Basaltic Cu (Cox and Singer, 1986; model 23).|
|Mineral deposit model number||23|
|Age of mineralization||The copper deposits are younger than a pre-Late Jurassic period of folding of basaltic host series (Stout, 1976, p. 30-31). They are probably Cretaceous or early Tertiary (see MH060).|
|Alteration of deposit||Propylitic alteration of basalt.|
|Workings or exploration||The occurrence was probably first reported in the early 1970s (Smith and others, 1973, 1975); it was revisited and sampled by the U.S. Geological Survey in the 1980s (Nokleberg and others, 1991).|
|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.
Smith, T.E., Kline, J.T., and Coursey, N.D., 1975, Analyses of stream-sediment samples, Mt. Hayes B-6 Quadrangle, south-central Alaska: Alaska Division of Geological & Geophysical Surveys Alaska Open-File Report 70, 2 p., 2 sheets, scale 1:63,360.
Smith, T.E., Trible, T.C., and Stein, D.R., 1973, Analyses of rock and stream-sediment samples, Mt. Hayes A-6 quadrangle, south-central Alaska: Alaska Division of Geological and Geophysical Surveys Geochemical Report 26, 1 plate, scale 1:63,360.
|Reporters||W.T. Ellis (Alaska Earth Science), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (USGS)|
|Last report date||8/1/2001|