Isótopos de Nd na proveniência de rochas e sedimentos da Bacia Potiguar, NE do Brasil

Nd ISOTOPES IN THE PROVENANCE OF TERRIGENOUS AND CARBONATE ROCKS AND SEDIMENTS OF THE POTIGUAR BASIN, NORTHEASTERN BRAZIL. Mesozoic and Cenozoic rocks from the Potiguar Basin, including terrigenous and carbonate sediments have been investigated to identify their isotopic signature and source areas....

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Detalles Bibliográficos
Autor: Maruoka, Miriam Tyoka da Silva
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2007
País:Brasil
Institución:Universidade Federal do Rio Grande do Norte (UFRN)
Repositorio:Repositório Institucional da UFRN
Idioma:portugués
OAI Identifier:oai:repositorio.ufrn.br:123456789/18804
Acceso en línea:https://repositorio.ufrn.br/jspui/handle/123456789/18804
Access Level:acceso abierto
Palabra clave:Proveniência
isótopos de Sm/Nd
bacia potiguar
plataforma continental
Provenance
Sm/Nd isotopes
potiguar basin
continental shelf
CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOFISICA
Descripción
Sumario:Nd ISOTOPES IN THE PROVENANCE OF TERRIGENOUS AND CARBONATE ROCKS AND SEDIMENTS OF THE POTIGUAR BASIN, NORTHEASTERN BRAZIL. Mesozoic and Cenozoic rocks from the Potiguar Basin, including terrigenous and carbonate sediments have been investigated to identify their isotopic signature and source areas. Additionally, this study aims to determine the provenance of terrigenous and carbonate sediments on the Brazilian Continental shelf adjacent to Potiguar Basin. The Sm-Nd isotopic signatures of the rocks yielded model ages (TDM) in the range of 2,19- 2,88 Ga, indicating archean to paleoproterozoic sources from the basement. The terrigenous sediments yielded model ages (TDM) in the range of 2,31-2,26 Ga, from 17,5 to 0 cm depth. Despite the small number of samples, limited variations of provenance ages indicates the homogenization of the sediments, probably due to the strong influence of the basement, as the main source of sediments to the shelf. The Sm-Nd isotopic signatures of the carbonate sediments yielded model ages (TDM) in the range of 2,09-2,61 Ga, indicating archean to paleoproterozoic sources from the basement. The results also indicate that the shelf sediments are mainly derived from the Açu River or other small rivers from the Setentrional Sector of Rio Grande do Norte State. The littoral drift doesn´t seem to contribute with sediments from the Oriental Sector since isotopic signatures from this sector were not detected.