Recurrent tectonic activity in northeastern Brazil during Pangea breakup: Constraints from U-Pb carbonate dating
Carlos E. Ganade, Cauê Rodrigues Cioffi, João Pacífico Machado, Tiago Siqueira de Miranda, Leonardo Brenguere Leão Lopes, Roberto F. Weinberg, Maria Alcione Lima Celestino, Bruno Carvalho, Marcel Guillong, Nick M.W. Roberts
Abstract
Abstract Carbonate U-Pb dating of samples from rift-bounding faults of intracontinental basins in the Borborema province, northeastern Brazil, indicate recurrent tectonic activity during Pangea breakup lasting for >150 m.y. from the Late Triassic to the Paleocene, reactivating inherited strike-slip Neoproterozoic–Cambrian shear zones. Triassic ages indicate that brittle deformation started some 80 m.y. before previously known, most likely related to rifting along the incipient Central Atlantic. The subsequent Cretaceous opening of the South Atlantic caused renewed fault activity during rifting and basin development. Furthermore, recurrent Cenozoic tectonic activity along the rift-bounding faults is indicated, suggesting that structural inheritance of the Neoproterozoic–Cambrian continental-scale Borborema shear zone system has been responsible for accommodation of recurrent tectonic stress from Mesozoic rifting to the present day.