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Charles T. Pierson

Publications and source records attributed to Charles T. Pierson.

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Reconnaissance for uranium in the coal of Sao Paulo, Santa Catarina, and Rio Grande do Sul, Brazil

Uranium-bearing coal and carbonaceous shale of the Rio Bonito formation of Pennsylvanian age have been found in the States of Sao Paulo, Santa Catarlna and Rio Grande do Sul, Brazil. The uranium oxide content of the samples collected in the State of Sao Paulo ranges from 0.001 percent to 0.082 percent. The samples collected in Santa Catarina averaged about 0.002 percent uranium oxide; those collected in Rio Grande do Sul, about 0.003 percent uranium oxide. Since the field and laboratory investigations are still in their initial stages, only raw data on the radioactivity and uranium content of Brazilian coals are given in this report.

Trace Elements Memorandum

Uraniferous coal and carbonaceous shale in northeast Parana, Brazil

Uraniferous coal has been found in northeast Parana, Brazil, in the Rio Bonito formation of Pennsylvanian age. In the majority of coal samples taken the uranium oxide content ranges from 0.005 to 0.030 percent, but selected screened samples have contained as much as 0.445 percent uranium oxide. The sampled thickness of the coal seam ranges from 17 to 54 centimeters and averages 31 centimeters. Channel samples across the entire thickness of the coal zone were taken in two places. All other samples were taken as grab samples from either mine waste dumps or coal zones that had high radioactivity. Sufficient information is not yet available to justify any detailed considerations of such features as geologic distribution, mode of occurrence, and radioactive equilibrium conditions of the uranium in the coal.

Trace Elements Memorandum

Reconnaissance for radioactive materials in the southern part of Brazil

During 1954-1956 a reconnaissance for radioactive minerals was made with carborne, airborne and handborne scintillation equipment in the southern Brazilian states of Rio de Janeiro, Sao Paulo, Parana, Santa Catarina and Rio Grande do Sul. During the traverse covering more than 5,000 kilometers the authors checked the radioactivity of Precambrian igneous and metamorphic rocks, Paleozoic, Mesozoic and Cenozoic sedimentary rocks, and Mesozoic alkalic intrusive and basaltic extrusive rocks. The 22 samples collected contained from 0.003 to 0.029 percent equivalent uranium oxide and from 0.10 to 0.91 percent equivalent thorimn; two samples were taken from radioactive pegmati tes for mineralogic studies. None of the localities is at present a commercial source of uranium or thorium; however, additional work should be done near the alkalic stock at Lages in the State of Santa Catarina and at the Passo das Tropas fossil plant locality near Santa Maria in the state of Rio Grande do Sul. Near Lages highly altered alkalic rock from a dike contained 0.026 percent uranium oxide. At Passo das Tropas highly altered, limonite-impregnated sandstone from the Rio do Rasto group of sedimentary rocks contained 0.029 percent uranium oxide.

Trace Elements Memorandum