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Kendell A. Dickinson

Publications and source records attributed to Kendell A. Dickinson.

At least 19 recordsLinked to original sources
USGS1987

Geology and origin of the Death Valley uranium deposit, Seward Peninsula, Alaska

A uranium deposit discovered in 1977 in western Alaska, by means of airborne radiometric data, is the largest known in Alaska on the basis of industry reserve estimates. At about latitude 65 degrees N, it is the most northerly known sandstone-type uranium deposit in the world. The deposit lies in Eocene continental sandstone near the eastern end of the Seward Peninsula, in the southern end of a graben that extends northward into the Death Valley depositional basin.The deposit is apparently of epigenetic and supergene origin. The uranium was derived from the Cretaceous granite of the Darby pluton that forms part of the western side of Death Valley. Uranium from primary mineralization is in the subsurface in a marginal facies of the Tertiary sedimentary basin where nearshore coarse clastic rocks are interbedded with coal and lacustrine clay. Primary mineralization occurred when uranium-bearing oxidizing ground water moved downdip from the pluton eastward through transmissive clastic beds or on the surface. Uranium was deposited where the coal or other carbonaceous material produced a reducing environment in arkosic host rocks. The supergene enrichment is related to a soil horizon at the present ground surface. The most common uranium mineral is meta-autunite, but cofflnite has been identified in the primary deposits. The host rocks for the primary deposits were partly covered by basalt flows that issued from nearby vents. Some of the basalt is highly altered, and some basalt float from the supergene zone has alteration rinds that are enriched in uranium.Extensive exploratory drilling took place from 1979 to 1981. The average grade of the potential ore is 0.27 percent U 3 O 8 and the average thickness is 3 m. The calculated reserves are 1,000,000 lbs U 3 O 8 ; additional drilling would probably add to this figure.

Alaska↗
USGS1981

Summary of radiometric anomalies in Alaska

The gamma ray anomalies and their related geological settings shown on this map are a compilation from the NURE reconnaissance surveys (LKB Resources Inc., 1978a, 1978b, 1978c, 1979; Texas Instruments, Inc., 1977, 1978, U.S. Research and Development, 1976; Western Geophysical Company of American, 1980.)

Alaska↗
USGS1979

A uranium occurrence in the Tertiary Kootznahoo Formation on Kuiu Island, southeast Alaska

Radioactive anomalies as high as 50 times background and uranium-bearing samples were discovered in parts of the nonmarine Tertiary Kootznahoo Formation in southeast Alaska by K. A. Dickinson and John Mitchell. Samples containing as much as 1300 ± 400 ppm uranium, measured by beta eU, were found. These samples have the highest uranium contents so far reported from Tertiary sedimentary rocks in southeast Alaska. Eakins (1975) reported two samples containing 12 and 13 ppm uranium and an anomaly of 13 times background from the same area. The purpose of this paper is to report the results of present studies and to suggest further work.

Alaska↗
USGS1977

Uranium and thorium distribution in soils and weathered bedrock in south Texas

The distribution of uranium and thorium in soils and weathered bedrock in areas of calich soil development on various kinds of sedimentary bedrock in south Texas indicates that uranium and thorium are leached from the surface layers and deposited deeper in the soil or weathered bedrock. The data provide field evidence that uranium is mobilized during dry-climate weathering, and suggest that caution be used in the interpretation of airborne, radioactive surveys that measure uranium at the surface.

Open-File Report↗