|Quadrangle map, 1:250,000-scale||HE|
|Quadrangle map, 1:63,360-scale||B-6|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Liberty prospect is at an elevation of about 2,700 feet on the broad flat ridge between Costello Creek and Colorado Creek. It is in sec. 18, T. 19 S., R. 10 W., of the Fairbanks Meridian. Access to the prospect is from the road to the Dunkle Coal mine. The prospect is approximately 200 feet east of the road and approximately 500 feet south of the airstrip. The location is accurate to within 500 feet. This is locality 3 of Cobb (1978: OFR 78-1062).|
Geologic descriptionThick Quaternary glacial deposits and Upper Tertiary sedimentary cover the older rocks in this area, which consist of Upper Jurassic to Upper Triassic(?) crystal tuff, argillite, chert, graywacke, and limestone. The older rocks are intruded by Late Cretaceous quartz diorite dikes, mainly along the nearby Chulitna fault (Wilson and others, 1998). The Liberty deposit consists of arsenopyrite-bearing quartz veins, reportedly in silicified limestone. Samples from trenches and pits contain 0.06-0.14 ounce of gold per ton and 1.2-8.6 ounces of silver per ton (Ross, 1933). Hawley and others (1978) report values of 0.005 to 0.06 ounce of gold per ton and traces of silver in samples from the same trenches sampled by Ross (1933).
|Geologic map unit||(-149.540289875343, 63.2625285734715)|
|Mineral deposit model||Low-sulfide Au-quartz vein (Cox and Singer, 1987; model 36a)|
|Mineral deposit model number||36a|
|Age of mineralization||Probably Late Cretaceous (70-65 Ma) or younger, assuming deposit is related to the diorite dikes.|
|Workings or exploration||Surface trenching and pitting. Samples from trenches and pits contain 0.06-0.14 ounce of gold per ton and 1.2-8.6 ounces of silver per ton (Ross, 1933). Hawley and others (1978) report values of 0.005 to 0.06 ounce of gold per ton and traces of silver in samples from the same trenches sampled by Ross (1933).|
|Indication of production||None|
Balen, M.D., 1990, Geochemical sampling results from Bureau of Mines investigations in the Valdez Creek mining district, Alaska: U.S. Bureau of Mines Open-File Report 34-90, 218 p., 2 sheets, scale 1:63,360.
Berg, H.C., and Cobb, E.H., 1967, Metalliferous lode deposits of Alaska: U.S. Geological Survey Bulletin 1246, 254 p.
Bundtzen, T.K., 1983, Mineral resource modeling, Kantishna-Dunkle mine-study areas: Alaska Division of Geological and Geophysical Surveys Report of Investigations 83-12, 51 p.
Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Healy quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-1062, 113 p.
Hawley, C.C., and Clark, A.L., 1974 (1975), Geology and mineral deposits of the upper Chulitna district, Alaska: U.S. Geological Survey Professional Paper 758-B, p. B1-B47, 2 plates, scale 1:12,000 and 1:48,000.
Hawley, C.C., and others, 1978, Mineral appraisal of lands adjacent to Mt. McKinley National Park, Alaska. Contract No. JO166107: U.S. Bureau of Mines Open-File Report 24-78, 274 p., 12 sheets.
Salisbury and Dietz, Inc., 1984, 1983 mineral resource studies--Kantishna Hills and Dunkle Mine areas, Denali National Park and Preserve, Alaska: U.S. Bureau of Mines, Contract No. S0134031, 1,080 p.
|Reporters||N. Van Wyck (Stevens Exploration Management Corporation); F.H. Wilson (USGS)|
|Last report date||3/28/2016|