|Quadrangle map, 1:250,000-scale||LC|
|Quadrangle map, 1:63,360-scale||B-8|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||About 13 km northeast of VABM Overlook, near where the southeast flowing Springway Creek enters the Mulchatna River. NW1/4 sec. 3, T. 4 N., R. 37 W., of the Seward Meridian. Locality is accurate to within 800 m.|
Spurr (1900) reported placer gold, too flaky and fine to save, 200 miles from mouth of river as early as 1890. Brooks (1904) reported gold has long been known in the upper reaches of the river. Placer said to yield $4-5 per day per man in 1903, but area too remote for mining. Cobb (1976) indicated he thought Brooks (in 1904 report) may have been discussing placers of Bonanza Creek.The most abundant bedrock in the areas upstream of the claims is unit KJs (Nelson and others, 1983). Unit KJs is described as interbedded lithic graywacke, silty sandstone, black shale , and local conglomerate. Irregular quartz segregations and veinlets are locally present. Scattered stocks and locally abundant dikes of intermediate to felsic composition intrude these sedimentary rocks. Adjacent to some of the larger igneous bodies are narrow contact aureoles of pelitic hornfels. Unit KJs is intruded (locally) by various Cretaceous to Tertiary plutons. The plutons include quartz monzonite, grano-diorite, diorite, and rhyolite dikes. Also present is Unit Tv of Nelson and others (1983) which includes rhyolitic breccia, ash-flow tuff, flows, and intrusive rocks and subordinate mafic to intermediate flows. Potassium-argon ages for unit Tv range from 56.2 to 62.7 m.y. (Eakins and others, 1978).
|Geologic map unit||(-155.695238597808, 60.4703086454717)|
|Mineral deposit model||Placer Au (Cox and Singer, 1986; model 39a)|
|Mineral deposit model number||39a|
|Age of mineralization||The placer gold is Quaternary, the source of gold could come from a variety of rocks with diverse ages.|
|Alteration of deposit||Not applicable|
|Workings or exploration||Three placer gold claims noted in 1973 by the U.S. Bureau of Mines.|
|Indication of production||Undetermined|
|Reserve estimates||No reserves|
|Production notes||No production|
Additional commentsCobb and Reed (1981) mention gold in most river bars of the Mulchatna River, with most prospecting occurring around the late 1890s or early 1900s.
Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-485, 101 p.
Cobb, E.H., and Reed, B.L., 1981, Summaries of data on and lists of references to metallic and selected nonmetallic mineral occurrences in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska; Supplement to Open-File Report 76-485; Part A, Summaries to January 1, 1981: U.S. Geological Survey Open-File Report 81-1343-A, 25 p.
Eakins, G.R., Gilbert W.G., and Buntzen, T.K., 1978, Preliminary bedrock geology and mineral resource potential of west-central Lake Clark quadrangle, Alaska: Alaska Division of Geological and Geophysical Surveys Open-File Report 118, 15 p., 2 plates, scale 1:25,000.
Martin, G.C., and Katz, F.J., 1910, Outline of the geology and mineral resources of the Iliamna and Clark lakes region: U.S. Geological Survey Bulletin 442-E, p. 179-200.
Smith, P.S., 1915, Mineral resources of the Lake Clark-Iditarod region: U.S. Geological Survey Bulletin 622-H, p. 247-271.
Smith, P.S., 1917, The Lake Clark-central Kuskokwim region, Alaska: U.S. Geological Survey Bulletin 655, 162 p.
Spurr, J.E., 1900, A reconnaissance in southwestern Alaska in 1898 in Walcott, C.D., Twentieth Annual report of the United States Geological Survey, 1898-1899: Part VII - Explorations in Alaska in 1898, p. 31-264.
U.S. Bureau of Mines, 1973, Alaska 1:250,000-scale quadrangle map overlays showing mineral deposit locations, principal minerals, and number and type of claims: U.S. Bureau of Mines Open-File Report 20-73, 95 overlays (updated in 1986, 1987).
|Reporters||D.P. Bickerstaff (USGS)|
|Last report date||6/15/1998|