Reconstruction of precambrian terranes of northeastern Brazil along cambrian strike-slip faults: A new model of geodynamic evolution and gold metallogeny in the State of Bahia

Abstract

Te Precambrian basement of Northeastern Brazil is the product of Rhyacian block convergence. Te main deformation and intrusion of crustal granitoids occurred between 2.15 and 1.8 Ga ago. Tis large area has been subjected to long-lasting and rather uniform stresses during the Cambrian period. Gold provinces in Bahia represent metallogenetic products of distinct tectonothermal events. Gold mineralization took place during the Paleoproterozoic collision and the Cambrian convergence, respectively, accompanied by heat flow, crustal deformation, and granite intrusion. Te tectonic framework of the region was reconstructed at ca. 700 Ma ago, considering the hypothesis of wrench-fault tectonics. Te new hypothesis provides geological evidence and metallogenic constraints that make further investigation necessary, with reference to well-established São Francisco Craton concept and its peripheral fold belts.