Quadrangle map, 1:250,000-scale | PE |
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Quadrangle map, 1:63,360-scale | D-6 |
Latitude | 56.80657 |
Longitude | -133.9509 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | This prospect consists of a number of radioactiive occurrences on northeastern Kuiu Island that consist of outcrops of Tertiary sandstone along the shoreline at the end of the peninsula that juts out between the mouth of Kadake Bay and the north end of Port Camden. These are commonly referred to as the Port Camden prospect. The coordinates are approximately at the center of the radioactive occurrences which are localities 7 and 8 of Grybeck, Berg, and Karl (1984). Called the the 'Kadake Bay' occurrence by Still and others (2002). |
Geologic descriptionThe Tertiary Kootznahoo Formation consists of light brown, poorly sorted, non-marine, dolomitic sandstone that contains clay clasts, carbonized wood fragments, and dolomitic concretions; thin shale layers are in the sandstone (Muffler, 1967). The sandstone ranges from silty, fine-grained and thin-bedded to medium- and coarse-grained; it is partly conglomeratic, and medium- to thick-bedded. Siderite, magnetite, pyrite, and apatite are present in some lithologies. All carbonized wood fragments show radioactivity when tested in place. Instrument readings varied from 2 to 50 times background. One sample gave readings in eU of 1300, plus-or-minus 400 parts per million (ppm) uranium, and gamma eU of 2300, plus-or-minus 700 ppm uranium. Samples from a four-inch-thick bed of fine-grained Tertiary sandstone contained 11 and 12 ppm uranium and up to 30 percent magnetite. (The description is summarized from Eakins, 1975; Dickinson, 1979; Dickinson and Campbell, 1982; Dickinson and Pierson, 1988; and Still and others, 2002). Still and others (2002) collected several samples of thin, black carbonaceous shale interbeds in the sandstone that gave slightly elevated readings on a Scintillometer; they contained up to 46 ppm uranium, 23 ppm lanthanum, and 41 ppm cerium. | |
Geologic map unit | (-133.9526242487, 56.8062301257881) |
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Mineral deposit model | Sandstone uranium (Cox and Singer, 1986; model 30c). |
Mineral deposit model number | 30c |
Age of mineralization | Tertiary or younger based on age of the host rock, the Tertiary Kootznahoo Formation. |
Workings or exploration | Block of 30 claims staked in 1976 and active until at least 1981 (U.S. Bureau of Mines, 1980). A few samples were collected and analyzed by the Bureau of Land Management (Still and others, 2002) but there has apparently been little private work done in recent years. |
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Indication of production | None |
Additional commentsThis area has been selected for transfer to Sealaska and the Kake Tribal Corporations and in 2002 was classified as 'interim conveyed, pending patent'. |
MRDS Number | A010324 |
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ReferencesStill, J.C., Bittenbender, P.E., Bean, K.W., and Gensler, E.G., 2002, Mineral assessment of the Stikine area, central Southeast Alaska: U.S. Bureau of Land Management Technical Report 51, 560 p.
U.S. Bureau of Mines, 1980, Claim map, Petersburg quadrangle, Alaska: U.S. Bureau of Mines Map 117, 1 sheet, scale 1:250,000.
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Reporters | D.J. Grybeck (Port Ludlow, WA) |
Last report date | 4/8/2007 |