New zircon U-Pb dating and review of geological and geochronological data with implications for lithostratigraphy and crustal evolution of North Borborema Province, northeastern Brazil

Abstract

The northern portion of the Borborema Province, located north of the Patos Shear Zone (northeast of Brazil) is formed by litho-stratigraphic units dating from the Archean to the Neoproterozoic, with complex evolution resulting from several orogenic and extensional events occurring in this interval. In this work, the litho-stratigraphic units of the Northern Borborema Province were reviewed and ordered here, regarding the rock associations and their chronological positioning. Zircon U-Pb dating of three samples of migmatitic orthogneisses from the Rio Piranhas-Seridó Domain, defined crystallization ages of 561 ± 2 Ma, 574 ± 6 Ma and 547 ± 5 Ma for their protoliths. Thus, the origin of the orthogneisses is related to the syn- to late-tectonic magmatism in relation to the Brasiliano Orogeny. From the Jaguaretama Complex, U-Pb dating of detrital zircons of a migmatitic schist indicates Paleoproterozoic sources, with a maximum deposition age of 2144 Ma. The protolith of a migmatitic orthogneiss has crystallization age of 2186 ± 10 Ma, therefore, contemporary compared to other litho-stratigraphic units of the Borborema Province, which are interpreted as having been developed in the Rhyacian Orogeny.