|Quadrangle map, 1:250,000-scale||UG|
|Quadrangle map, 1:63,360-scale||D-5|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This site represents beach placer deposits which extend from 4 miles north of Cape Greig (Ugashik D-5) northward to 4 1/2 miles south of Goose Point (Naknek A-5), a total of 13 miles (MacKevett and Holloway, 1977, locality 9; Church and others, 1989: MF-1539I, locality 21).|
This site represents black sand beach placer deposits tested by the U.S. Bureau of Mines in 1969 (Kimball, 1972). The beach consists of silt to large boulder-sized detritus. The coarser material is mostly of igneous origin, and is thought to have been transported from the Aleutian Range. The finer material consists mostly of quartz and feldspar.
Black sand occurs as a veneer, generally forming thin layers or lenses, that covers wide sections of the upper part of the beach. These layers or lenses rarely exceed 6 inches thick, but one layer measured 14 inches. Buried layers were generally of the same thickness. Some of the black sand lenses are up to a 100 feet long, but most are short and narrow, and rarely cover an acre. A magnetic survey failed to detect any large buried bodies of black sand. Magnetite and ilmenite are abundant in the black sands, however hypersthene is the dominant mineral.The U.S. Bureau of Mines drilled 21 holes along 13 miles of this beach. Hole depths ranged from 2 to 4 feet. They collected 125 samples, 89 of which contained trace to 0.007 ounce of gold per ton.
|Geologic map unit||(-157.642099436564, 57.8792582981241)|
|Mineral deposit model||Placer gold-PGE (Cox and Singer, 1986; model 39a)|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary.|
|Workings or exploration||The U.S. Bureau of Mines drilled 21 holes in these deposits in 1969 (Kimball, 1972). Of 125 samples, 89 contained trace to 0.007 ounce of gold per ton.|
|Indication of production||None|
Additional commentsThis occurrence is on state land.
Church, S.E., Detterman, R.L., and Wilson, F.H., 1989, Mineral and energy resource assessment maps of the Ugashik, Bristol Bay, and western Karluk quadrangles, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF 1539-I, 2 map sheets, scale 1:250,000.
Cobb, E.H., 1980, Summaries of data and lists of references to metallic and selected nonmetallic mineral deposits in fifteen quadrangles in southwestern and west-central Alaska: U.S. Geological Survey Open-File Report 80-909, 103 p.
Kimball, A.L., 1972, Reconnaissance of Ugashik beach sands, Bristol Bay, Alaska: U.S. Bureau of Mines Open-File Report 21-72, 28 p.
|Reporters||S.H. Pilcher (Anchorage)|
|Last report date||2/1/2000|