|Quadrangle map, 1:250,000-scale||UG|
|Quadrangle map, 1:63,360-scale||A-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is located near Kilokak Creek on Cape Kilokak north of triangulation point Imuya in T. 35 S., R. 44 W., of the Seward Meridian (MacKevett and Holloway, 1977, locality 13; Nokleberg and others,1987, locality AP 15). The site location is accurate to within 3 miles.|
At this site sedimentary rocks of the Cretaceous Hoodoo and Chignik Formations and Eocene Tolstoi Formation are cut by the northern part of the Pliocene Agripina batholith (Detterman and others, 1987). The batholith also intrudes sills, dikes, and volcanic rocks of Oligocene age.
The occurrence is marked by a color anomaly, mostly in the sedimentary rocks, and by copper, gold, lead, molybdenum, tungsten, and zinc anomalies in stream sediments from Kilokak Creek (Church and others, 1989: B-1858). Tourmaline and barite have been found in panned concentrates from this drainage.
Bear Creek Mining company examined and sampled the area in 1977 (Hedderly-Smith, 1977). Pyrite, in amounts of 2-3 percent, was the only sulfide mineral reported. Rock-chip sampling indicated only low level metal anomalies. Except for localized silicification, little alteration was found.Nokleberg and others (1987) describe a zone of alteration and sparse veining within a black shale member of the Hoodoo Formation. The veins are anomalous in lead and zinc. They also report an unaltered andesite plug (Oligocene?) which is surrounded by an extensive zone of disseminated pyrite in the surrounding sedimentary rocks.
|Geologic map unit||(-156.40206163663, 57.1992765376128)|
|Mineral deposit model||Polymetallic vein? (Cox and Singer, 1986; model 22c)|
|Mineral deposit model number||22c?|
|Age of mineralization||Tertiary or younger.|
|Alteration of deposit||The rocks exhibit only localized silicification.|
|Workings or exploration||A stream-sediment geochemical survey was done here by Resource Associates of Alaska in 1975. Bear Creek Mining Company mapped and sampled the prospect in 1977 (Hedderly-Smith, 1977). The U.S. Geological Survey geochemically sampled the stream-sediments in the 1980s (Church and others, 1989: B-1858). Anomalous values of copper, gold, lead, molybdenum, tungsten and zinc were reported.|
|Indication of production||None|
Additional commentsThis site is located on land selected by the Koniag Native Corporation.
Church, S.E., Detterman, R.L., and Wilson, F.H., 1989, Mineral and energy resource assessment maps of the Ugashik, Bristol Bay, and western Karluk quadrangles, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF 1539-I, 2 map sheets, scale 1:250,000.
Church, S.E., Frisken J.G., and Wilson, F.H., 1989, Interpretation of exploration geochemical data from Ugashik, Bristol Bay, and western Karluk quadrangles, Alaska: U.S Geological Survey Bulletin 1858, 45 p.
Detterman, R.L., Case, J.E., Wilson, F.H., and Yount, M.E., 1987, Geologic map of the Ugashik, Bristol Bay, and part of the Karluk quadrangles, Alaska: U.S. Geological Survey Miscellaneous Investigation Series Map I-1685, 1 sheet, scale 1:250,000.
Hedderly-Smith, D.A., 1977, 1977 Annual report, Alaska search, Koniag Inc. region: Bear Creek Mining Company, Spokane Office, 23 p. (Report held by Kennecott Alaska, Anchorage).
MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous mineral deposits in the western part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-F, 38 p., 1 sheet, scale 1:1,000,000.
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.
|Reporters||S.H. Pilcher (Anchorage)|
|Last report date||2/1/2000|