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Granites are of prime importance in studies of orogenic belts because they are related in space and time with the orogen evolution, isolating snapshots of the superimposed deformations as they freeze part of their structural evolution. Collisional granites in orogenic belts are also important because the minimum lengh of time that an orogeny last can be estimated from their age.
The Sergipano Belt is one of the most significant Precambrian orogenic belts of Northeastern Brazil, not only because it was considered as evidence for continental drift, but also because it contains several structural and lithologic domains that allow it to be compared with Phanerozoic orogens. The Sergipano Belt was formed by continental collision between the Congo-São Francisco Craton and the Pernambuco-Alagoas Massif during the Brasiliano/Pan-African Orogeny, and it is a key belt for reconstructing part of the history of West Gondwana. It comprises five lithostructural domains: Canindé, Poço Redondo-Marancó, Macururé, Vaza Barris and Estncia limited each from the other by the shear zones. Three major deformation episodes have been recognized in the Sergipano Belt: D1, D2 and D3 events. D2 is the main collisional event in the belt and it was responsible for the generation of major ductile structures in the this belt, during which several granitic plutons were emplaced mainly in Macururé Domain (MRD). According to the main continental event in Sergipano Belt, the D2 event, these granites are divided in two group, the pre-collisional and the syn-collisional granites. The pre-collisional plutons are bodies of restrict ocurrence in the MRD and comprises calc-alkaline strong deformed granite-granodiorites with mafic enclaves. The syn-collisional plutons occur in all part of MRD and these plutons comprised mostly by pink granites and less often by granodiorites and are emplaced as sheets along the S2-related axial plane foliation or it is collected at the hinge zones of F2 folds. The syn-collisional granites are little deformed but it shows evidence of solid state deformation such as a recrystallization by subgrain rotation and boundary migration of quartz and feldspar and static recrystallization of quartz grains. A U-Pb SHRIMP zircon age of 628±12 Ma was obtained for the pre-collisional Camará tonalite. Two U-Pb TIMS titanite ages was obtained for the syn-collisional granites, 584±10 Ma for the Angico granite and 571±9 Ma for the Pedra Furada granite wich represents the last pulses of collisional magmatism in the MRD. The ages obtained for the collisional granites are close to the 570±34 obtained for the peak of metamorphism in the Sergipano Belt. The U-Pb age obtained for the Camará tonalite together with the U-Pb age obtained for the Pedra Furada granite mark the beginning and the end of the D2 event in MRD, respectively. Using these ages we have the main Neoproterozoic collisional D2 event operating in the Sergipano Belt during about 57 million years.
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