|Quadrangle map, 1:250,000-scale||TC|
|Quadrangle map, 1:63,360-scale||A-6|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Shalosky prospect is about 8.4 miles west of the junction of the Tok and Dry Tok Rivers. It is about 1.6 miles south-southwest of VABM 7302 'White'; about 0.5 mile southeast of the center of section 19, T. 16 N., R. 8 E., of the Copper River Meridian. The location is accurate within 1/4 mile.|
The rocks in the area are part of the Tok Schist and consists mainly of quartz-muscovite schist with a thick layer of quartz-chlorite schist (Rhyolite Resources Ltd., 2012a). The Tok Schist is cut by several steep to vertical faults, one of which control the trend of the mineralization at the Shalosky prospect. To the north across a north-dipping thrust fault, the rocks are a folded sequence of argillaceous sediments, felsic-sulphidic schist, chlorite schist, feldspar-quartz schist, banded sedimentary rocks, and gabbro. The age of the rocks is uncertain; Foster (1970) only indicates that they are Paleozoic or Mesozoic.
The mineralization in the area is sediment hosted and controlled by structure; it is associated with zones of silicification and quartz-vein stockwork (Rhyolite Resources Ltd., 2012b). Sulfides vary from 1 to more than 20 percent of the mineralization. There is a strong geochemical association of the gold with arsenic and antimony; copper, lead, zinc, bismuth, tellurium, and silver are low.
From 1998 through 2001, Grayd Resources and Placer Dome Inc. explored the area (Rhyolite Resources Ltd., 2012a; 2012b). They collected many rock and geochemical samples, trenched, and drilled 12 holes totaling 1,174 meters, but the data are not publicly available. In 2009, Rhyolite Resources acquired the property and identified 3 high-priority areas that included the Shalosky prospect.
Placer Dome drilled at least two holes at the Shalosky prospect (Rhyolite Resources Ltd., 2012a; 2012b). Some notable intercepts were 38.2 meters with 0.8 gram of gold per tonne, including 1.3 meters with 17.8 grams of gold per tonne; and 17.5 meters with 1.2 grams of gold per tonne, including 7.0 meters with 2.2 grams of gold per tonne.Rhyolite Resources Ltd. (2012a; 2012b) diamond drilled eight holes totaling 1,388 meters, along about 600 meters of the Shalosky zone. The zone is associated with a regional east-northeast striking, steeply dipping, mineralized structure up about 35 meters wide that appears to widen at depth. Seven of the eight holes cut significant gold mineralization. Some notable intercepts are 23.1 meters with 3.5 grams of gold per tonne, and 69.0 meters with 1.7 grams of gold per tonne. The mineralization occurs in two styles. The highest-grade mineralization with values of 5 to 23 grams of gold per tonne is associated with quartz veins and several periods of brecciation. Lower grade mineralization with values from 0.2 to 4 grams of gold per tonne is associated with pervasive hydrothermal alteration characterized by intense clay alteration and local silicification.
|Geologic map unit||(-143.96404045809, 63.1478236123159)|
|Mineral deposit model||Gold-quartz in veins and brecciated zones; lower grade disseminated mineralization? (Cox and Singer, 1986; model 22c)|
|Mineral deposit model number||22c?|
|Age of mineralization||Unknown other than that it is younger than the Paleozoic or Mesozoic host rocks (Foster, 1970).|
|Alteration of deposit||Lower grade mineralization is characterized by intense clay alteration and local silicification (Rhyolite Resources Ltd., 2012b).|
|Workings or exploration||
The earliest documented samples of gold mineralization from Shalosky Prospect were collected in 1995 by geologist Bill Shalosky exploring on behalf of American Copper & Nickel Company, Inc. (S. Dashevsky, written communication, 2014).From 1998 through 2001, Grayd Resources and Placer Dome Inc. explored the area (Rhyolite Resources Ltd., 2012a). They collected many rock and geochemical samples, trenched, and drilled 12 holes totaling 1,174 meters in the area but the data are not publicly available. Placer Dome drilled at least two holes at the Shalosky prospect (Rhyolite Resources Ltd., 2012b). In 2009, Rhyolite Resources acquired the property and identified 3 high-priority areas that included the Shalosky prospect. Rhyolite diamond drilled 8 holes totaling 1,388 meters, along about 600 meters of the Shalosky zone (Rhyolite Resources Ltd., 2012a; 2012b).
|Indication of production||None|
Cox, D.P., and Singer, D.A., eds., 1986, Mineral deposit models: U.S. Geological Survey Bulletin 1693, 379 p.
Foster, H.L., 1970, Reconnaissance geologic map of the Tanacross quadrangle, Alaska: U.S. Geological Survey Miscellaneous Geological Investigations Map I-593, 1 sheet, scale 1:250,000.
Rhyolite Resources Ltd. 2012a, (Corporate Presentation): http://www.rhyoliteresources.com/in/pdf/CorporatePresentation.pdf (as of February 18, 2012).
Rhyolite Resources Ltd., 2012b, Projects overview: http://www.rhyoliteresources.com/s/Projects.asp (as of February 23, 2012).
|Reporters||D.J. Grybeck (Contractor, USGS); V.C. Zinno (Alaska Earth Sciences, Inc.)|
|Last report date||12/3/2014|