|Quadrangle map, 1:250,000-scale||CV|
|Quadrangle map, 1:63,360-scale||B-7|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This site is located on Hinchinbrook Island and occupies an area of approximately 0.25 sq. mi. in the center of sec. 34, T. 17 S., R. 7 W., of the Copper River Meridian. The center of the area is at approximately the 1500 ft elevation. Location is accurate to within 600 ft. Shown as site C-98 in Jansons and others (1984).|
Geologic descriptionThis occurrence consists of a 30 x 90 ft. outcrop area of manganese-bearing nodules and encrustations in an interbedded sequence of sedimentary and volcanic rocks of the Tertiary Orca Group (Nelson and others, 1985). The occurrence is interpreted as a sedimentary manganese deposit developed on the sea floor (Goodfellow and others, 1984). Selected samples contained 29-35 percent Mn, 14 percent Fe, 6700 ppm Ba, 3400 ppm Zn (Goodfellow and others, 1984).
|Geologic map unit||(-146.427022389102, 60.3514449961353)|
|Mineral deposit model||Volcanogenic Mn (Cox and Singer, 1986; model 24c)|
|Mineral deposit model number||24c|
|Age of mineralization||Probably Tertiary based on the age of the host rocks.|
|Workings or exploration||
Site discovered during regional geologic mapping (Nelson and others, 1985). Minor interest by industry during exploration activity in mid-1980s.Selected samples contained 29-35 percent Mn, 14 percent Fe, 6700 ppm Ba, 3400 ppm Zn (Goodfellow and others, 1984).
|Indication of production||None|
Additional commentsLocation is within the Chugach National Forest.
Goodfellow, R., Nelson, S.W., Bouse, R.M., and Koski, R.A., 1984, The geologic setting and composition of a newly discovered manganese deposit on Hinchinbrook Island, Alaska: U.S. Geological Survey Open-Fle Report 84-671, 10 p.
Jansons, Uldis, Hoekzema, R.B., Kurtak, J.M., and Fechner, S.A., 1984, Mineral occurrences in the Chugach National Forest, southcentral Alaska: U.S. Bureau of Mines Mineral Land Assessment 5-84, 218 p., 2 sheets, scale 1:250,000.
|Reporters||S.W. Nelson, Anchorage, AK|
|Last report date||6/10/2000|