|Quadrangle map, 1:250,000-scale||HE|
|Quadrangle map, 1:63,360-scale||D-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Gold placer mining activity has taken place for at least 2 miles along Homestake Creek and its upstream continuation Platte Creek. The map site is in sec. 5, T. 11 S., R. 5 W., of the Fairbanks Meridian. This is location 57 of Clark and Cobb (1972).|
Geologic descriptionUpper Platte Creek drains en Eocene to Miocene sequence of poorly consolidated pebbly sandstone, claystone, and subbituminous coal (Wilson and others, 1998). Lower Platte Creek to its junction with Fox Creek drains schist of the Keevy Peak Formation, which is intruded by Tertiary hypabyssal granitic rocks. The workings at Platte Creek are in well-sorted and rounded gravels 3 to 6 feet thick. Most of the gold is in the lower 2 to 3 feet of the gravel and upper part of schist bedrock. Pay streaks 25 to 60 feet wide were reported (Cobb, 1973: B1374). In Homestake Creek, the gravels are coarse and poorly sorted, and contain abundant cobble and boulder-sized clasts that include large angular blocks of andesite. The gravels in Platte Creek were reported to carry 0.14 ounce of gold per cubic yard. Gravels on bedrock downstream contained 0.14 to 0.43 ounce of gold per cubic yard (Capps, 1912). The most probable sources of the placer gold are Tertiary paleoplacers formed during an earlier erosional cycle of the Alaska Range.
|Geologic map unit||(-148.562330333752, 63.969548371784)|
|Mineral deposit model||Placer Au (Cox and Singer, 1986; model 39a)|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary.|
|Workings or exploration||Surface only. The gravels in Platte Creek were reported to carry 0.14 ounce of gold per cubic yard. Gravels on bedrock downstream contained 0.14 to 0.43 ounce of gold per cubic yard (Capps, 1912).|
|Indication of production||Yes; small|
|Production notes||Most of the production occurred before 1912.|
Additional commentsThe stream gradient in Platte Creek is 100 feet per mile; in Homestake Creek it is 200 feet per mile.
|MRDS Number||A011345; A015351|
Berg, H.C., and Cobb, E.H., 1967, Metalliferous lode deposits of Alaska: U.S. Geological Survey Bulletin 1246, 254 p.
Capps, S.R., 1912, The Bonnifield region, Alaska: U.S. Geological Survey Bulletin 501, 64 p., 1 sheet, scale 1:250,000.
Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Healy quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-1062, 113 p.
|Reporters||N. Van Wyck (Stevens Exploration Management Corporation)|
|Last report date||4/7/2000|