|Quadrangle map, 1:250,000-scale||SI|
|Quadrangle map, 1:63,360-scale||C-7|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The nine unpatented claims of the Woll prospects constitute the Lucky Shot Group on the west side of Lake Anna (Reed and Coats, 1941). This site consists of two prospects about 1,000 feet apart on the northwest shore of the lake, west-northwest of the channel to Sister Lake. A third prospect, about a mile to the south, is described in ARDF record SI105. For this record, the site is is plotted at sea level about 0.6 mile northeast of the center of section 11, T. 49 S., R. 58 E. It is location P-82 of Bittenbender and others (1999), location 36 of Cobb (1972, 1978), and MAS no. 0021140058 (U.S. Bureau of Land Management, 2002). The location is accurate within 0.2 mile.|
Johnson and Karl (1985) map the rocks in the area of this prospect as Cretaceous graywacke and argillite interbedded with sparse, lenticular beds of basalt. The rocks are cut by numerous high-angle, mainly northwest-striking faults. These include the extensions of the fault at the Chichagof Mine (SI093) which controls the mineralization there and crosses this prospect.
Reed and Coats (1941) describe the workings on this prospect as a 48-foot tunnel with 10- and 15-foot drifts and a 14-foot winze that explore fault-controlled, auriferous quartz veins in graywacke. The graywacke strikes N45W and dips 72SW; the fault strikes N3-17W and dips 41SW to 51NW. The fault contains up to 3 inches of gouge, up to 12 inches of banded quartz, and a quartz lens up to 2 feet thick; irregular quartz veinlets cut the graywacke footwall of the quartz lens. The quartz contains fragments of silicified and sericitized graywacke, and locally considerable galena and sphalerite. A nearby vuggy quartz vein up to 6 inches thick contains pyrrhotite and arsenopyrite.
Bittenbender and others (1999), citing Still and Weir (1981), report that U.S. Bureau of Mines samples of graywacke-hosted, mineralized quartz at this prospect contained up to 0.51 ounce of gold per ton. Workings include 3 adits and several trenches. There is no record of production, but the assay data and the extent of the workings suggests that some gold may have been produced.Isotopic studies indicate that the gold-quartz veins in coastal southern and southeastern Alaska are Eocene, about 50 Ma in age (Haeussler and others, 1995; Goldfarb, 1997; Goldfarb and others, 1997). ARDF record SI087 provides an overview of the geology of auriferous quartz veins in the Chichagof Mining District.
|Geologic map unit||(-136.057321573286, 57.6415309007151)|
|Mineral deposit model||Polymetallic vein (Cox and Singer, 1986; model 22c).|
|Mineral deposit model number||22c|
|Age of mineralization||Isotopic studies indicate that the gold-quartz veins in coastal southern and southeastern Alaska are Eocene, about 50 Ma in age (Haeussler and others, 1995; Goldfarb, 1997; Goldfarb and others, 1997).|
|Alteration of deposit||Fragments of graywacke in the quartz veins are silicified and sericitized.|
|Workings or exploration||Reed and Coats describe the workings on this prospect as a 48-foot tunnel with 10- and 15-foot drifts and a 14-foot winze. Bittenbender and others report 3 adits and several trenches.|
|Indication of production||Undetermined|
|Production notes||There is no record of production, but the assay data and the extent of the workings suggests some gold may have been produced.|
Additional commentsThe prospect is in West Chichagof-Yakobi Wilderness.
Bittenbender, P., Still, J.C., Maas, K., and McDonald, M., Jr., 1999, Mineral resources of the Chichagof and Baranof Islands area, southeast Alaska: Bureau of Land Management, BLM-Alaska Technical Report 19, 222 p.
Cobb, E.H., 1972, Metallic mineral resources map of the Sitka quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-467, scale 1:250,000.
Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Sitka quadrangle: U.S. Geological Survey Open-File Report 78-450, 124 p.
Goldfarb, R J., 1997, Metallogenic evolution of Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 4-34.
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.
Haeussler, P J., Bradley, D., Goldfarb, R., Snee, L., and Taylor, C., 1995, Link between ridge subduction and gold mineralization in southern Alaska: Geology, v. 23, no. 11, p. 995-998.
Reed, J.C., and Coats, R.R., 1941, Geology and ore deposits of the Chichagof mining district, Alaska: U.S. Geological Survey Bulletin 929, 148 p.
Roehm, J.C., 1936, Preliminary report of Mike Woll prospect, Lake Ann, west coast Chichagof Island, Sitka Mining District, Alaska, July 7, 1936: Alaska Territorial Department of Mines, Property Examination 114-5, 1 p.
Still, J.C., and Weir, K.R., 1981, Mineral land assessment of the west portion of western Chichagof Island, Southeast Alaska: U.S. Bureau of Mines Open-File Report 89-81, 269 p., 12 sheets.
U.S. Bureau of Land Management, 2002, Alaska mineral locations database report (Sitka quadrangle), July 2, 2002, 205 p. [http://imcg.wr.usgs.gov/dem.html]
|Reporters||H.C. Berg (U.S. Geological Survey)|
|Last report date||10/16/2004|