Natural radionuclides from U-238 and TH-232 series and inorganic chemical characterization of soil profiles and sediment cores of the Taia??upeba Reservoir, S??o Paulo, Brazil

• Autor(a) principal: SOUZA, J.M.
• Data de Publicação: 2018
• Outros Autores: DAMATTO, S.R., LEONARDO, L., SURKOV, A.M., SILVA, A.R., MADUAR, M.F., GON??ALVES, P.N., INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE
• Tipo de documento: Artigo de conferência
• Título da fonte: Repositório Institucional do IPEN
• Texto Completo: http://repositorio.ipen.br/handle/123456789/28254
• topic: geochemical surveys; concentration ratio; geophysical surveys; natural radioactivity; radioecological concentration; sediments; soils; thorium 232; uranium 238; water reservoirs

Taia??upeba reservoir, located in the state of S??o Paulo, Brazil, belongs to Producer System of Alto Tiet?? (Sistema Produtor Alto Tiet??) and it is responsible for water supply for about 3.1million of people. The water quality of a reservoir is very important, but this is reduced by the increase of environmental degradation of the soil around the reservoir and its different uses. The study of soil profiles and sediment cores is an important tool for understanding the geophysical and geochemical aspects of an aquatic ecosystem. The objective of this work was to present the natural radionuclides 238U, 226Ra, 210Pb, 232Th, 228Th, 228Ra and 40K activity concentrations and also the inorganic chemical characterization of four soil profiles and four sediment cores collected in the area of influence area of Taia??upeba reservoir. The analytical techniques, gamma spectrometry and instrumental neutron activation analysis were used in the determination. In the soil profiles the highest activity concentrations were obtained for the radionuclides 40K and 228Th and the lowest for 210Pb; in the sediment cores the highest activity concentrations were obtained for the radionuclide 210Pb and the lowest for 226Ra and 228Ra. For the inorganic chemical characterization the highest values obtained were for Na, As and Sb; in a sediment core a very high concentration was obtained for the element Zn indicating a probable accumulation of this element inside the reservoir; enrichment factor was used to evaluate a possible anthropic contamination in the soil and sediment at the margins of Taiacupeba reservoir.