Banca de QUALIFICAÇÃO: LARISSE BARBOSA DA CRUZ

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : LARISSE BARBOSA DA CRUZ
DATE: 27/01/2022
TIME: 09:00
LOCAL: videoconferência https://www.youtube.com/channel/UCCBwJxTIfyeGmQSqDLK6duw
TITLE:

Peraluminous Ediacaran plutonism of the Seridó Belt, NE Brazil: petrographic and
geochemical characterization

KEY WORDS:

Rio Piranhas-Seridó Domain; mineralogy; lithogeochemistry; tectonics

PAGES: 23
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUMMARY:

In the Borborema Province (northeast Brazil) there is a wide distribution of granitic bodies related to Ediacaran to Cambrian magmatism as part of the final phase of the Brasiliana/Panafrican orogeny. The Jardim do Seridó Suite (GJS), outcropping in the southern portion of the municipality of Jardim do Seridó / RN, is a representative of this magmatism and the object of this study. The main body has an outcrop area of about 30.8 km². For the characterization of the base, field relationships, petrography, mineral and whole rock chemistry were used. This suite is predominantly composed of leucogranites intrusive in rocks of the Seridó Group (especially micaschists) with different proportions of biotite, muscovite, garnet, biotite, silimanite and andalusite. The rocks are metaluminous to peraluminous (A / CNK = 0.95-5.84, with normative corundum between 1.30 and 14.03). Petrographic criteria, such as inclusions of mafic minerals in quartz and feldspar, and geochemical criteria, such as regular distribution in diagrams, point to fractional crystallization of alkaline feldspar, plagioclase, garnet, biotite, magnetite and apatite; with CF rate of approximately 80% like. A fundamental geochemical analysis of the origin of these granites by 75% partial melting of a crustal source (aluminous metasediments). Diagrams discriminate the collision-type tectonic environment.

BANKING MEMBERS:
Interno - 2042352 - FREDERICO CASTRO JOBIM VILALVA
Externo ao Programa - 3149236 - RAFAEL GONCALVES DA MOTTA
Interno - 350630 - ZORANO SERGIO DE SOUZA