U-Pb dating of granites in the Neoproterozoic Sergipano Belt, NE-Brazil: Implications for the timing and duration of continental collision and extrusion tectonics in the Borborema Province

摘要: Abstract The Sergipano Belt is the outcome of collision between Pernambuco–Alagoas Massif and Sao Francisco Craton during Neoproterozoic assembly West Gondwana. Field relationships U–Pb geochronology granites intruded in garnet micaschists Macurure Domain are used to constrain main collisional event (D 2 ) belt. divided into two groups, pre-collisional (pre- early-D syn-collisional (syn- tardi-D ), latter were emplaced as sheets along S axial plane foliation or they collected at hinge zones F folds. A SHRIMP zircon age 628 ± 12 Ma was obtained for Camara tonalite. Two TIMS titanite ages granites, 584 ± 10 Ma Angico granite 571 ± 9 Ma Pedra Furada granite, these close garnet-whole rock Sm–Nd isochron 570 Ma found peak metamorphism Belt. tonalite (628 Ma) (571 Ma) mark respectively maximum beginning D minimum end Domain. Using ages, has been operation least 57 million years. Correlation with coeval granitoids farther north Borborema Province indicate that while syn-D (ca. 590–570 Ma) under compression, extensional conditions related regional strike-slip shear zones. These contrasting emplacement settings contemporaneous explained by a combination continent–continent extrusion tectonics.