|Quadrangle map, 1:250,000-scale||RB|
|Quadrangle map, 1:63,360-scale||B-5|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Crooked Creek is marked by a strip mine labeled on the Ruby B-5 quadrangle (USGS topographic map, 1952, minor revisions in 1973). The mine is located just north of Crooked Creek, on a west bench of Birch Creek. The above coordinates mark the center of mining and correspond to location 7 of Cobb (1972 [MF405]), in section 12, T. 12 S., R. 17 E. of the Kateel River Meridian. The location is accurate.|
The type of bedrock underlying the Crooked Creek mine is not known because of the substantial thickness of Quaternary deposits (Puchner and others, 1998). A small pay streak is located near the mouth of Crooked Creek itself, and further deposits are located several hundred yards up Crooked Creek from Birch Creek (Chapman and others, 1963). The downstream deposits of Crooked Creek mix with the cassiterite-bearing Birch Creek deposits and Cobb and Chapman (1981) speculate that at least some of the Crooked Creek deposits contained cassiterite although there is no record of any recovered (Cobb and Chapman, 1981).Shafts were first sunk approximately 50 feet to bedrock on a low silt terrace south of the creek prior to 1936, however, only a little gold was found (Mertie, 1936). Intermittent mining has been done on the area from its discovery to the present. Strip mining has been done on the lower part of the creek (Eberlein and others, 1977).
|Geologic map unit||(-155.378499081164, 64.4563381103951)|
|Mineral deposit model||Placer Au (Cox and Singer, 1986; model 39a).|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary?|
|Workings or exploration||Shafts were sunk approximately 50 feet to bedrock, and strip mining was done on the lower part of the creek (Mertie, 1936; Eberlein and others, 1977).|
|Indication of production||Yes; small|
Additional commentsSee also Birch Creek (RB035).
Chapman, R.M., Coats, R.R., and Payne, T.G., 1963, Placer tin deposits in central Alaska: U.S. Geological Survey Open-File Report 239, 53 p.
Cobb, E.H., 1972, Metallic mineral resources map of the Ruby quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-405, 1 sheet, scale 1:250,000.
Cobb, E.H., 1977, Placer deposit map of central Alaska: U.S. Geological Survey Open-File Report 77-168-B, 64 p., 1 map, scale 1:1,000,000.
Cobb, E.H., and Chapman, R.M., 1981, Mineral occurrences (other than mineral fuels and construction materials) in the Kantishna River and Ruby quadrangles, Alaska: U.S. Geological Survey Open-File Report 81-170, 94 p.
Eberlein, G.D., Chapman, R.M., Foster, H.L., and Gassaway, J.S., 1977, Map and table describing known metalliferous and selected nonmetalliferous mineral deposits in central Alaska: U.S. Geological Survey Open-File Report 77-168-D, 132 p., 1 sheet, scale 1:1,000,000.
Mertie, J.B., Jr., 1936, Mineral deposits of the Ruby-Kuskokwim region, Alaska: U.S. Geological Survey Bulletin 864-C, p. 115-245.
|Reporters||C.E. Cameron (Alaska Division of Geological and Geophysical Surveys)|
|Last report date||3/22/2000|