Dados da Submissão

Título

PETROGENESIS OF THE DRIFT MAGMATISM IN CABO FRIO HIGH, CAMPOS BASIN, BRAZIL: EVIDENCE FROM Sr-Nd-Pb-Hf ISOTOPES

Texto do resumo

Located between the Campos and Santos basins, the Cabo Frio High is characterized by intense magmatic activity during the Santonian-Campanian and Eocene post-breakup periods. The geodynamic context associated with these events took place during the passive margin stage of these basins, where magmatism could be related to reactivation of major structures or thermal increment by adjacent hotspot (i.e., Trindade Martin Vaz Plume) in a thin lithosphere environment. This study presents new Sr-Nd-Pb-Hf isotope data from alkaline magmatic rocks from three wells located in the Cabo Frio High area. Evolution of these rocks involved assimilation-fractional crystallization processes. Results of analysis and binary mixing modeling point out to an involvement of both depleted (DM/MORB or HIMU) and enriched (EMI and EMII) in the formation of these magmas. The additional contribution of a fertile OIB-like source might be associated with the Trindade Martin Vaz Plume.

Palavras Chave

alkaline magmatism; Campos Basin; Sr-Nd-Pb-Hf isotope geochemistry.