Estratigrafia química aplicada à Formação Codó (Aptiano/Albiano da Bacia do Parnaíba)

• Autor(a) principal: Bastos, Lucas Pinto Heckert
• Data de Publicação: 2017
• Outros Autores: [e-mail]
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/17153
• topic: Chemostratigraphy; Organic geochemistry; Parnaíba Basin; Codó Formation; Aptian; Estratigrafia química; Geoquímica orgânica; Bacia do Parnaíba; Formação Codó; Aptiano; Geologia estratigráfica – Cretáceo – Parnaíba, Rio, Bacia (PI e MA); Geoquímica – Parnaíba, Rio, Bacia (PI e MA); Paleogeografia – Parnaíba, Rio, Bacia (PI e MA); Sedimentação e depósitos – Parnaíba, Rio, Bacia (PI e MA); CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS

The sedimentary record of Brazilian Cretaceous reflects an evolutionary period of extreme importance in the context of the tectonic evolution of the South American platform. The Codó Formation (Aptian/Albian of the Parnaíba Basin) records thick shales packages, and other evaporitic, carbonate and siliciclastic facies.These shales were analyzed using geochemical methods (Total Organic Carbon, Pyrolysis Rock- Eval and Biomarkers) and carbon stable isotopes of organic matter, to help in the characterization of the depositional environment of this unit, as well to contribute to the understanding of the paleogeographic evolution of the Brazilian Cretaceous. Nitrogen stable isotopes was applied and the evaluation from the perspective of the Nitrogen cycle suggests that the main dominant processes in the paleoenvironment were denitrification and volatilization of ammonia. The presence of marine geochemical indicators, coupled with evidence of hypersalinity and the facies arrangement, led the interpretation of a model of the Gulf as possible depositional settings of this unit, called informally at this study as Codó Gulf.