| Quadrangle map, 1:250,000-scale | SO |
|---|---|
| Quadrangle map, 1:63,360-scale | C-5 |
| Latitude | 64.656 |
| Longitude | -164.294 |
| Nearby scientific data | Find additional scientific data near this location |
| Location and accuracy | The Silver prospect is located on the nose of a low ridge between lower Big Hurrah Creek and Solomon River. It is at an elevation of about 260 feet, on the north side of Big Hurrah Creek, about 0.5 miles northeast of its mouth. It is locality 16 of Cobb (1972, MF 445; 1978, OF 78-181). |
Geologic descriptionAt least two quartz veins with ribbon rock in graphitic schist are present; these contain free gold and locally arsenopyrite (Cathcart, 1922). Vein widths vary from 0.5 to 3 feet, they strike northwest up to several hundred feet and dip south (Asher, 1969, DGGS R33). Eighteen samples of various mineralized rocks contained 0.01 to 1.53 ounces of gold per ton and a trace to 0.70 ounces of silver per ton (Asher, 1969, DGGS R33, p. 17); a grab sample of dump material contained 2.2 ounces of gold per ton. Anderson (1947) reports that a small amount of scheelite is present in the quartz veins. The country rock is part of a lower Paleozoic metasedimentary assemblage that includes a distinctive black, very fine-grained, graphitic schist (Sainsbury and others, 1972; Till and others, 1986). These veins may be same age as some other gold-quartz veins of southern Seward Peninsula. The southern Seward Peninsula lode gold deposits formed as a result of mid-Cretaceous metamorphism (Apodoca, 1994; Ford, 1993, Ford and Snee, 1996; Goldfarb and others, 1997) that accompanied regional extension (Miller and Hudson, 1991) and crustal melting (Hudson, 1994). This higher temperature metamorphism was superimposed on high pressure/low temperature metamorphic rocks of the region. | |
| Geologic map unit | (-164.296605544877, 64.6552574381743) |
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| Mineral deposit model | Gold-quartz vein in metamorphic rocks; low sulfide-Au quartz vein (Cox and Singer, 1986; model 36a). |
| Mineral deposit model number | 36a |
| Age of mineralization | Cretaceous? |
| Alteration of deposit | Silicification. |
| Workings or exploration | There are 5 shafts and numerous surface pits and trenches. The 40- to 60- foot-deep Goode shaft was inclined 26 degrees at S 60 W and had 800 feet of workings; the 45-foot-deep Shamrock shaft was inclined 71 W; the 11-foot-deep Hot Air shaft was 8 by 10 feet in cross-section in 1934; no data are available for the other two shafts located near the Goode shaft. The longest surface trench was 50 feet long and 3 to 8 feet deep. A small mill was erected on the property some time after 1938. |
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| Indication of production | Undetermined |
| MRDS Number | A012590; D002600 |
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ReferencesApodoca, L.E., 1994, Genesis of lode gold deposits of the Rock Creek area, Nome mining district, Seward Peninsula, Alaska: Boulder, Colorado, University of Colorado, Ph.D. dissertation, 208 p.
Ford, R.C., 1993, Geology, geochemistry, and age of gold lodes at Bluff and Mt. Distin, Seward Peninsula, Alaska: Golden, Colorado School of Mines, Ph.D. dissertation, 302 p.
Ford, R.C., and Snee, L.W., 1996, 40Ar/39Ar thermochronology of white mica from the Nome district, Alaska--The first ages of lode sources to placer gold deposits in the Seward Peninsula: Economic Geology, v. 91, p. 213-220.
Goldfarb, R.J., Miller, L.D., Leach, D.L., and Snee, L.W, 1997, Gold deposits in metamorphic rocks in Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 151-190.
Hudson, T.L., 1994, Crustal melting events in Alaska, in Plafker, G., and Berg, H. C., eds., The Geology of Alaska: Geological Society of America, DNAG, The Geology of North America, Vol. G-1, p. 657-670.
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| Reporters | Travis L. Hudson (Applied Geology) |
| Last report date | 8/19/1999 |