|Quadrangle map, 1:250,000-scale||SR|
|Quadrangle map, 1:63,360-scale||B-3|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The prospect is located near tidewater on the east side of the most northeasterly arm of Lower Herring Bay. It is in the NE1/4 section 31, T. 4 N., R. 10 E., of the Seward Meridian. This is location 207 Tysdal (1978 [MF-880-A]) and location S-72 of Jansons and others (1984). This location is accurate to within a quarter of a mile.|
Geologic descriptionThe prospect consists of a 3-inch-thick, light-green, siliceous layer in nearly flat-lying pillow basalts that has been penetrated by a 19-foot adit (Kurtak and Jeske, 1986). The siliceous layer is subparallel to the flow direction of the greenstone and contains pyrite, as much as 10 percent pyrrhotite and as much as 1 percent chalcopyrite (Johnson, 1918 [B 662-C, p. 193-220]; Kurtak and Jeske, 1986). The basalt is mapped as Orca Group of early Tertiary age (Nelson and others, 1985; Cobb and Tysdal, 1980). The adit is driven into a west-facing cliff and trends S 65 E. Two samples were collected, one from the cliff and one from the adit. The silicified greenstone sample contained 175 ppm copper and 2.3 ppm silver; the pillow basalt sample contained 78 ppm copper and 0.28 ppm silver (Kurtak and Jeske, 1986).
|Geologic map unit||(-147.77815152241, 60.3947392553887)|
|Mineral deposit model||Cyprus massive sulfide (Cox and Singer, 1986; model 24a)|
|Mineral deposit model number||24a|
|Age of mineralization||Tertiary or younger; the mineralization is in rocks of the Orca Group of Tertiary age.|
|Workings or exploration||Workings consist of a single 19-foot, S 65 E-trending adit driven into a west-facing cliff. Two samples were collected, one from the cliff face and one from the adit. The silicified greenstone sample from the adit contained 175 ppm copper and 2.3 ppm silver; the pillow basalt sample from the cliff face contained 78 ppm copper and 0.28 ppm silver (Kurtak and Jeske, 1986).|
|Indication of production||None|
Cobb, E.H., and Richter, D.H., 1972, Metallic mineral resources map of the Seward quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-466, 2 sheets, scale 1:250,000.
Condon, W.H., and Cass, J.T., 1958, Map of a part of the Prince William Sound area, Alaska, showing linear geologic features as shown on aerial photographs: U.S. Geological Survey Miscellaneous Investigations Series Map I-273, 1 sheet, scale 1:125,000.
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.
Johnson, B.L., 1918, Copper deposits of the Latouche and Knight Island districts, Prince William Sound: U.S. Geological Survey BuIletin 662-C, p. 193-220.
Kurtak, J.M., and Jeske, R.E., 1986, Mineral investigations in the Chugach National Forest, Alaska (Islands area): U.S. Bureau of Mines Open-File Report 54-86, 302 p., 1 sheet, scale 1:63,360.
MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000.
Nelson, S.W., Dumoulin, J. A., and Miller, M.L., 1985, Geologic map of the Chugach National Forest, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1645-B, 16 p., 1 sheet, scale 1:250,000.
|Reporters||Jeff A. Huber and Carol S. Huber (Anchorage)|
|Last report date||12/7/2001|