|Quadrangle map, 1:250,000-scale||SB|
|Quadrangle map, 1:63,360-scale||D-5|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrrence is on the Kupreanof Peninsula, near the head of Osterback Creek (MacKevett and Holloway, 1977, locality 6; Wilson and others, 1988, locality 6). The map site is at an elevation of 1,500 feet, 0.2 mile southeast of the center of sec. 1, T. 51 S., R. 67 W., of the Seward Meridian. The location is accurate to within 2 miles.|
Geologic descriptionThere are contradictory descriptions of the geology of the area of this occurrence. MacKevett and Holloway (1977) and Hollister (1978) reported several altered zones in Tertiary bedded rocks, in or near Tertiary granitic plutons. Hollister (1978) classified the plutons as quartz diorite and reported a color anomaly marking areas of stockwork mineralization accompanied by phyllic, argillic, and propylitic alteration. In the mid-1980s the U.S. Geological Survey mapped the rocks in the area as Eocene to Oligocene Meshik Formation, and did not report any granitic rocks (Wilson and others, 1995). They collected few samples that were reported to be anomalous in copper, silver, and zinc (Wilson and others, 1988).
|Geologic map unit||(-159.572088580016, 55.7891958724572)|
|Age of mineralization||Tertiary.|
|Alteration of deposit||Hollister (1978) reported phyllic, propylitic, and argillic alteration in an area marked by a large color anomaly.|
|Workings or exploration||The U.S. Geological Survey mapped and sampled this area in the mid-1980s. Samples 83AYb590-594 and 83AWs78-81 were reported to be anomalous in copper, zinc, and silver (Wilson and others, 1988).|
|Indication of production||None|
Additional commentsThis occurrence is in the Alaska Peninsula National Wildlife Refuge, near the boundary of land selected by the Bristol Bay Native Corporation.
Angeloni, L.M., Wilson, F.H., and Sutley, S.J., 1985, Map and tables showing preliminary rock geochemical data, Port Moller, Stepovak Bay, and Simonof Island quadrangles, Alaska: U.S. Geological Survey Open-File Report 85-470, 179 p., 1 sheet, scale 1:250,000.
Hollister, V.F., 1978, Geology of the porphyry copper deposits of the Western Hemisphere: Society of Mining Engineering, American Institute of Mining, Metallurgy, and Petroleum Engineers Inc., 218 p.
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.
Wilson, F.H., Detterman, R.L., Miller, J. W., and Case, J.E., 1995, Geologic map of the Port Moller, Stepovak Bay, and Simeonof Island quadrangles, Alaska: U.S. Geological Survey Miscellaneous Investigation Series Map I-2272, 1 sheet, scale 1:250,000.
|Last report date||11/7/2000|