The Zona Transversal Domain of the Borborema Province, northeastern Brazil: synthesis of the Archean to Cambrian evolution, and new tectono-stratigraphic interpretation

Abstract

The Transversal Zone Domain (TZD) is the central segment of the Borborema Province, with its limits given by the Patos and Pernambuco shear zones, to the north and south respectively. This part of the province presents Archean nuclei surrounded by Paleoproterozoic units that together correspond to the basement of belts of Neoproterozoic metasupracrustal rocks. All this set was intruded by syn to post-tectonic granitoids related to the Brasiliano Orogeny (c. 640 – 500 Ma). The TZD records important shear zones of regional scale, dextral (Patos and Pernambuco), and sinistral (Serra do Caboclo, Afogados da Ingazeira and Congo), being the dextral used to delimit the TZD of adjacent domains and the sinistral ones for internal compartmentalization in four subdomains: Piancó-Alto Brígida, Alto Pajeú, Alto Moxotó and Rio Capibaribe. The lithostratigraphic units of this domain were described and organized in a way that would be regionally presentable. An unprecedented dating is presented for a metagranitoid of the Serra de Jabitaca Complex, with maximum crystallization age at 1790 ± 40 Ma and metamorphism at 615 ± 3 Ma. The tectonic evolution of the domain begins with an orogenic event and development of magmatic arches at the beginning of the Paleoproterozoic (involving Archean portions), in addition to an extensional event at the end of this period, already in the transition with the Mesoproterozoic. The Neoproterozoic begins with two extensional events (Cariris Velhos and pre-Brasiliano) until the formation of the magmatic arches related to Brasiliano Orogeny.