Banca de DEFESA: THAIANNE RODRIGUES DA SILVA GUEDES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : THAIANNE RODRIGUES DA SILVA GUEDES
DATA : 09/04/2021
HORA: 14:00
LOCAL: https://conferenciaweb.rnp.br/webconf/natali-da-silva-barbosa
TÍTULO:

Subalkaline and Alkaline Magmatism from the Correntina-Coribe Erosive Window rocks, West of the São Francisco Craton: Comparative study with the Guanambi-Urandi Monzosienitic Batholith

PALAVRAS-CHAVES:

São Francisco Craton; Coribe Correntina Erosive Window; Paleoproterozoic rocks; Lithogeochemistry; Alkaline and sub-alkaline magmatism

PÁGINAS: 67
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Geociências
SUBÁREA: Geologia
ESPECIALIDADE: Geoquímica
RESUMO:

The "Correntina-Coribe Erosive Window" represents the basement of the São Francisco Craton in the western region of Bahia and is characterized by the exposure of Paleoproterozoic rocks. The lithostratigraphic context is represented by the Correntina Migmatitic Gneiss Complex (CGMC), the Extrema Metavolcanosedimentary Sequence, also called Extreme Formation and the Rio Correntina Intrusive Suite (SIRC). The CGMC and SIRC, the main object of this study, are formed by sub-alkaline and alkaline rocks, respectively. The CGMC comprises deformed rocks such as orthogneisses, paragnaisses, migmatites and non-deformed rocks of monzogranitic, tonalitic and granitic composition. The rocks present enrichment in ETRL and LILEs in relation to ETRP and HFSE. The multi-element diagrams are characterized by valleys in Nb, Ti, Ta, Eu and P and peaks in U and Th. The geochemical characterization together with data available in the literature corroborate a genesis associated with partial melting processes of subducted oceanic lithosphere (MORB) for these rocks. The SIRC is formed by syenites and syenogranites that occur mainly in the form of slabs and blocks without showing evident deformation. The rocks are enriched in LILE and depleted in HFSE. They have slightly positive europium anomalies. The multi-element diagrams are characterized by valleys in Nb, Ti and Ta and peaks in Ba and La. The geochemical characteristics of this unit indicate an origin related to the melt of the metasomatized lithospheric mantle. In both units studied, evolutionary trends present fractional crystallization as the main mechanism in the generation of rocks. In the discriminating diagrams of the tectonic environment, the CGMC rocks plot between the intra-plate / sin-collisional and volcanic arc fields, while those of the SIRC in the boundary field related to the intra-plate (WPG), sin and post-collisional environment

MEMBROS DA BANCA:
Presidente - 2689540 - NATALI DA SILVA BARBOSA
Externo(a) ao Programa - 1248799 - REINALDO SANTANA CORREIA DE BRITO
Externo(a) à Instituição - DAVID JOZEF CORNELIUS DEBRUYNE - UFPel