Application of neutron activation analysis to the study of low-titanium tholeiitic dykes of the Serra do Mar Swarm (RJ)
Carregando...
Data
Data de publicação:
2019
Autores IPEN
Orientador
Título da Revista
ISSN da Revista
Título do Volume
É parte de
É parte de
É parte de
É parte de
INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE
Exportar
Resumo
The tholeiitic dykes of the Serra do Mar Swarm (SMS) outcrop along the coast of the São Paulo and Rio de
Janeiro states (Southeastern Brazil), spreading over the Rio Paraiba Valley. Previous studies carried out in such
dykes showed that they are related to the tectonic and magmatic processes that took place during the South
Atlantic Ocean opening and gave rise to the Paraná Magmatic Province (PMP). The dykes are vertical to subvertical
and preferentially NE-SW trending, with thicknesses ranging from centimeters to tens of meters. Most of
the SMS intrusive rocks have relatively high concentrations of TiO2 (>3wt%), except for occurrences in the
Região dos Lagos (Costa Azul Suite), as well as around Nova Friburgo Town (Serrana Suite), where they are
characterized by basic rocks with low TiO2 (<2wt%) contents, whose genesis are still not completely understood.
Therefore, a detailed study is being carried out in rocks of the Suite Serrana, with the determination of the
concentrations of the rare earth (REE: La, Ce, Nd, Sm, Eu, Tb, Yb, and Lu) and other trace (Ta, Th, U, Hf, Cs,
Sc, and Co) elements by instrumental neutron (thermal and epithermal) activation analysis, which has accuracy
and precision required for petrogenetic studies. The data obtained so far show a substantial enrichment of highly
incompatible trace elements (light REE, Th and U) and a remarkable geochemical similarity with the low-TiO2
basaltic flows of Gramado type found in southern PMP, suggesting important processes of crustal contamination
during the genesis of the investigated dykes.
Como referenciar
COTIS, DÉBORA S.; MARQUES, LEILA S.; FIGUEIREDO, ANA M.G.; CORVAL, ARTUR; VALENTE, SÉRGIO C. Application of neutron activation analysis to the study of low-titanium tholeiitic dykes of the Serra do Mar Swarm (RJ). In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 330-343. Disponível em: http://repositorio.ipen.br/handle/123456789/30355. Acesso em: 20 Apr 2024.
Esta referência é gerada automaticamente de acordo com as normas do estilo IPEN/SP (ABNT NBR 6023) e recomenda-se uma verificação final e ajustes caso necessário.