THE BORBOREMA OROGEN: USING PETROCHRONOLOGY AND THERMOCHRONOLOGY TO CONNECT MAGMATIC AND METAMORPHIC PROCESSES IN OROGENIC SETTINGS (CHRONOBORO)

• Grant number: 24/20149-3
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2025
• End date: July 31, 2028
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Maria Helena Bezerra Maia de Hollanda
• Grantee: Maria Helena Bezerra Maia de Hollanda
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Andreas Zametzer ; Bruno Vieira Ribeiro ; Carlos Fernando Ávila Rodrigues ; Carlos José Archanjo ; Daniel Souza dos Santos ; Frederico Meira Faleiros ; João Adauto de Souza Neto ; Laécio Cunha de Souza ; Mauricio Parra Amézquita ; Renato de Moraes

Abstract

This is a scientific proposal to apply petrological and geochronological techniques and methods to solve shortcomings related to the space and time connection between geological processes in orogenic domains. The proposal will focus on a (today) deeply eroded region in NE Brazil - the Rio Grande do Norte domain, inserted into the northern segment of the Borborema Province. There, the Brasiliano setting records the juxtaposition of metasedimentary rocks, recording low-greenschist and upper-amphibolite-facies metamorphism adjacent to granitic batholiths and plutons. Ca-rich metasomatic skarns and massive isolated LCT-type pegmatites form a large polymetallic province hosted in the regional metapelites, in which W, Mo (+Au, Bi, Cu), Li, and Nb-Ta occurrences and deposits have been described. The temporal relationship between the granites, pegmatites, and skarn rocks has not been solved; genetic links are still unclear. To address these issues, we intend to critically explore mineral (major, trace, and isotope) chemistry and dating of specific metamorphic and igneous minerals to support petrological assessments and to reconstruct the chronological timeline of the magmatic-metamorphic-metasomatic processes in the northern Borborema Province. In this sense, we also expect to contribute to Pegmatology research, an actual topic of increasing scientific and prospective interest in geosciences that is favorable to be investigated in this key area of the province. (AU)