Bachelor Creek Mine, Circle District, Yukon-Koyukuk Borough, Alaska, USA
Latitude & Longitude (WGS84): | 65° 29' 27'' North , 146° 3' 32'' West |
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Latitude & Longitude (decimal): | 65.4908333333, -146.058888889 |
Gold reported on Preacher Creek in 1913 may have been on Loper or Bachelor Creek. Numerous claims staked on Preacher Creek in 1928 and 1976 to 1981. See also Loper Creek, ARDF no. CI035.
Location: Bachelor Creek can be accessed via a 4-wheel drive road from the Steese Highway at mile marker 80.1. The 4-wheel drive road runs along the west side of the state highway maintenance station fence. Mining occurred along the east side of the creek at 65.4828 N, 146.0575 W.
Geology: Traverses in the upper Bachelor Creek basin indicate that it is underlain, in part, by light gray or rusty-weathering felsic schists and quartzites and by abundant graphitic schist and quartzite. Sulfide minerals appear to be concentrated in stratiform layers, especially in the graphitic rocks. In some hand specimens, sulfides make up 15 to 20 percent of the rock. Pyrite is the most common sulfide, and chalcopyrite and arsenopyrite are present in many of the rocks. Pyrrhotite is common in the graphitic zones. Both felsic and graphitic schists contain elevated abundances of gold, copper and tungsten. The felsic schists and associated light-colored quartzites contain up to 240 ppb Au, 4300 ppm Cu, 2100 ppm As, 4 ppm Ag, 4.5 ppm Sb, 130 ppm Sb, 14 ppm Pb, 90 ppm Sn and 3100 ppm W. In these rocks gold correlates with copper, and to a lesser extent, with arsenic. High tungsten-tin values inversely correlate to gold-base metal values. Graphitic schists and quartzites are less well mineralized with concentrations of Au to 180 ppb, Cu to 1600 ppm and W to 110 ppm (T.E. Smith and others, 1987, p. 6-10 to 6-11). Bedrock in the area is composed of both schist and granite porphyry. Bedrock schist is primarily quartz-mica, quartzitic, and carbonaceous. These Paleozoic and (or) Precambrian schists are cut by a 75 foot thick sill-like body of granite porphyry. The schistosity and sill strike N 60 E. Gravels are thin (7 to 8 feet thick) or absent and are thawed. Gravels are composed of schist, abundant vein quartz, and some granite porphyry clasts. The only gold occurrence reported is on a low, 20 foot thick gravel bench on the east side of the creek (Prindle, 1910, p. 208-209). Gravel on a low bench east of the stream was sluiced in 1910 (Cobb, 1973, p. 123, [B 1374]). A man recently reported finding a 1.2 ounce gold nugget on Bachelor Creek (Lampright, 1996, p.55).
Workings: Gravel on a low bench east of the stream was sluiced in 1910 (Cobb, 1973, p. 123, [B 1374]). A man recently reported finding a 1.2 ounce gold nugget on Bachelor Creek (Lampright, 1996, p.55).
Production: Gravel on a low bench east of the stream was sluiced in 1910 (Cobb, 1973, p. 123, [B 1374]), however amount of production is unknown.
Commodities (Major) - Au
Development Status: Yes; small
Deposit Model: Placer gold deposit (Cox and Singer, 1986; model 39a)
Mineral List
1 valid mineral.
Major Regional Geological Units
This information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the geology at this locality but it gives a background for the region in which it is found.
Silurian-Devonian 358.9 - 443.8 Ma | Quartzite and pelitic schist |
Devonian - Cambrian 358.9 - 541 Ma | Sedimentary; Sedimentary: undivided |
Devonian - Neoproterozoic 358.9 - 1000 Ma | Neoproterozoic-Devonian sedimentary |
Neoproterozoic 541 - 1000 Ma | Neoproterozoic intrusive and metamorphic terranes Intrusive and metamorphic terranes Mixtures of metamorphic and intrusive or plutonic rocks, tracts known as crystalline, migmatitic terranes, moderately to highly metamorphosed rocks of unknown origin with or without intrusions. This classification is inherently prone to variable interpretation, as other compilers might distinguish some packages by their metamorphic or gneissic protoliths, and the associated age ranges may be more variable. |
References for regional geology:
Data provided by Macrostrat.org
J.C. Harrison, M.R. St-Onge, O.V. Petrov, S.I. Strelnikov, B.G. Lopatin, F.H. Wilson, S. Tella, D. Paul, T. Lynds, S.P. Shokalsky, C.K. Hults, S. Bergman, H.F. Jepsen, and A. Solli. Geological map of the Arctic. doi:10.4095/287868. Geological Survey of Canada Map 2159A.
Garrity, C.P., and Soller, D.R.,. Database of the Geologic Map of North America: adapted from the map by J.C. Reed, Jr. and others (2005). U.S. Geological Survey Data Series 424 .
Geological Survey of Canada. Generalized geological map of the world and linked databases. doi:10.4095/195142. Open File 2915d.
Wilson, F.H., Hults, C.P., Mull, C.G, and Karl, S.M. (compilers). Geologic map of Alaska. doi: 10.3133/sim3340. U.S. Geological Survey Scientific Investigations Map 3340, pamphlet 196.