|Quadrangle map, 1:250,000-scale||CI|
|Quadrangle map, 1:63,360-scale||C-3|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Location of claims is about 100 yards east of Bedrock Creek and 50 yards upstream of the Steese Highway bridge.|
Geologic descriptionCountry rock is dominantly Paleozoic and (or) Precambrian Yukon-Tanana terrane quartz-mica schist containing numerous discontinuous quartz veins, intruded by lower Tertiary granite of the Circle pluton. Nelson, West, and Matzko (1954) reported 10% monazite, 5% topaz and a small amount of scheelite in the heavy-mineral fraction of the granite bedrock. Other minerals present are pyrrhotite, garnet, ilmenite, zircon, biotite, topaz and malachite. Two other samples from the area are slightly anomalous in tungsten (2-3 ppm), fluorine (2300-2400 ppm), lead (11-25 ppm), and arsenic (12-24 ppm) (Nelson and others, 1954). Concentrates from gravel on upper Bedrock Creek contain tin and tungsten (Barker, 1979). Fluorometric tests indicated the presence of uranium in several minerals but not in amounts to be of economic interest. A slightly radioactive zone of iron-stained schist 0.5 to 2 feet wide by 8 feet long was staked for uranium. This iron-stained schist gave a radiometric reading of about 0.05 mR/hr while the unstained schist gave a reading of 0.04 mR/hr (Freeman, 1963, p. 32). Work on claims between 1976 and 1978 consisted of surface trenching on the slightly radioactive zone of the iron-stained schist. Bedrock Creek is noted for its absence of gold, even though it is surrounded by gold-producing creeks such as Independence, Mammoth, Crooked and Boulder Creeks (Yeend, 1991, p. 31).
|Geologic map unit||(-145.098461168126, 65.549633021249)|
|Workings or exploration||Claims located 100 yards east of the creek were active in 1976-1978. Workings consisted of surface trenching of a slightly radioactive zone of iron-stained schist 0.5 to 2 feet wide by 8 feet long. This iron-stained schist gave a radiometric reading of about 0.05 mR/hr while the unstained schist gave a reading of 0.04 mR/hr (Freeman, 1963, p. 32).|
|Indication of production||None|
Additional commentsSite of localized radioactive anomaly; low grade and small size. Apparently no potential for uranium of economic importance.
|MRDS Number||A012246; A012254; D002679|
Barker, J.C., 1979, A trace element study of the Circle mining district, Alaska: U.S. Bureau of Mines Open-File Report 57-79, 74 p.
Berg, H.C., and Cobb, E.H., 1967, Metalliferous lode deposits of Alaska: U.S. Geological Survey Bulletin 1246, 254 p.
Cobb, E.H., 1972, Metallic mineral resources map of the Circle quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-391, 1 sheet, scale 1:250,000.
Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Circle quadrangle, Alaska: U.S. Geological Survey Open-File Report 76-633, 72 p.
Eberlein, G. D., Chapman, R. M., Foster, H. L., and Gassaway, J. S., 1977, Map and table describing known metalliferous and selected nonmetalliferous mineral deposits in central Alaska: U.S. Geological Survey Open File Report 77-168D, 132 p.
Freeman, V.L., 1963, Examination of uranium prospects, 1956, in Contributions to economic geology of Alaska: U.S. Geological Survey Bulletin 1155, p. 29-33.
Menzie, W.D., Foster, H.L., Tripp, R.B., and Yeend, W.E., 1983, Mineral resource assessment of the Circle quadrangle, Alaska: U.S. Geological Survey Open-File Report 83-170-B, 61 p., 1 sheet, 1:250,000.
Nelson, A.E., West, W.S., and Matzko, J.J., 1954, Reconnaissance for radioactive deposits in eastern Alaska, 1952: U.S. Geological Survey Circular 348, 21 p.
Nokleberg, W.J., Bundtzen, T.K., Berg, H.C., Brew, D.A., Grybeck, D.J., Robinson, M.S., Smith, T.E., and Yeend, W., 1987, Significant metalliferous lode deposits and placer districts of Alaska: U.S. Geological Survey Bulletin 1786, 104 p., 2 plates, scale 1:5,000,000.
Overstreet, W.C., 1967, The geologic occurrence of monazite: U.S. Geological Survey Professional Paper 530, 327 p.
|Reporters||C.J. Freeman, J.R. Guidetti Schaefer, A.S. Clements (Avalon Development Corporation)|
|Last report date||5/22/1998|