|Quadrangle map, 1:250,000-scale||MH|
|Quadrangle map, 1:63,360-scale||B-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The area of the occurrences is at an elevation of about 4,150 feet about midway between lower Rainy Creek and Ann Creek. It is in the NE1/4NE1/4 section 4, T. 19 S., R. 10 E., Fairbanks Meridian.|
Geologic descriptionThere are three occurrences. One consists of orange lichen-covered boulders of dunite containing traces of pyrite and pyrrhotite (W.T. Ellis, oral communication, 2001). About 2,000 feet to the southwest chalcopyrite is disseminated in malachite-stained hornfelsed strata adjacent to a gabbro dike that cuts the dunite (W.T. Ellis, oral communication, 2001). A sample of chromite-bearing dunite collected about 1,000 feet to the northeast contained more than 5,000 parts per million chromium (Nokleberg and others, 1991, sample 79HZ005A). Airborne magnetic data for this area show a large circular high that connects with the southeast part of the Rainy ultramafic-mafic complex intrusive (MH164) of Late Triassic age. The complex intrudes the Slana Spur Formation of Pennsylvanian age (Nokleberg and others, 1991).
|Geologic map unit||(-145.833754948137, 63.303484179458)|
|Mineral deposit model||Ni-Cu-PGE in differentiated mafic-ultramafic sill; Cu skarn (Cox and Singer, 1986; model 18b).|
|Mineral deposit model number||18b|
|Age of mineralization||Late Triassic or younger.|
|Alteration of deposit||Local serpentinization of ultramafic rocks; contact metamorphism of sedimentary rocks; oxidation of copper minerals.|
|Workings or exploration||
A sulfide-bearing dunite sample collected by American Copper And Nickel Company contained 0.43 percent nickel, 0.24 percent copper, 216 parts per billion (ppb) palladium, 295 ppb platinum, and 245 ppb gold. A sample of copper-bearing hornfels contained 8.9 percent copper, 0.006 percent zinc, and 140 ppb gold.The occurrences are on active claims of MAN Resources.
|Indication of production||None|
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||6/14/2002|