GRANITIC MAGMATISM AT THE NORTHWESTERN REGION OF THE FLORIANÓPOLIS BATHOLITH: PETROGENESIS AND TECTONIC HISTORY

• Grant number: 24/14843-4
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: February 01, 2025
• End date: February 29, 2028
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Miguel Angelo Stipp Basei
• Grantee: Ana Clara Santana Jardim Vidal Ferreira
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The southern portion of the Mantiqueira Province is formed by the Dom Feliciano Belt, which extends from Santa Catarina to Uruguay. The Florianópolis Batholith crops out in the state of Santa Catarina and corresponds to significant Neoproterozoic magmatism, being composed of granitic suites. Isotropic to deformed equigranular to porphyritic syeno to monzogranites occur in the northwest region of the Florianópolis Batholith, with biotite and hornblende as mafic minerals, with crystallization between 614 and 583 Ma. This magmatism encompasses units of the Major Gercino Shear Zone, Águas Mornas suites, São Pedro of Alcântara and Pedras Grandes, as well as bodies located in a stratigraphic window within the Paraná Basin, the Picadas Association. This research has two objectives: (i) reevaluate the geological data available for the northwest region of the Florianópolis Batholith and (ii) propose a petrogenetic model aiming to understand the tectonics involved in the generation of rocks. For this, the methods to be applied are: (i) petrographic characterization, (ii) elemental (major and trace), mineral (zircon, plagioclase and hornblende) and isotopic (Sm-Nd, Rb-Sr and Lu-Hf) geochemistry, (iii) U-Pb geochronology in zircon and titanite, (iv) revaluation of cartographic data and (v) integration of analytical results to interpret the evolution model. Two main results are expected: (i) the homogenization of data and the update of the geological information for this region and (ii) the formulation of a petrogenetic model. It is expected that this petrogenetic model will contribute to the discussion of the tectonic evolution of the Florianópolis Batholith by bringing new data and models.