The unsteady post-rift stage of the South American passive margin based on the tectono-sedimentary evolution of the onshore Paraiba Basin, NE Brazil

Author(s)

Andrades-Filho, Clodis de Oliveira ; Rossetti, Dilce de Fatima ; Rego Bezerra, Francisco Hilario

• Document type: Journal article
• Source: QUATERNARY INTERNATIONAL; v. 580, p. 20-pg., 2021-03-16.

Abstract

The post-rift tectono-sedimentary history of passive margins has been an issue of increased interest after the perception of their unsteady nature during the Neogene and Quaternary. The evolution of the eastern South America margin might be benefited from investigations of the sedimentary record in a number of marginal basins. The Para?ba Basin is of particular interest to discuss the post-rift evolution of the South American passive margin, because it represents the last bridge with the African plate. This work aims to analyze the post-rift sedimentary record of the onshore Para?ba Basin as a contribution to discuss the neotectonic history of the South American passive margin. Surface and subsurface data were integrated from outcrops, deep stratigraphic profiles, airborne geophysical maps and remote sensing products. The depositional and denudational processes in this basin were a result of tectonic subsidence and uplifting. Tectonics after the main rifting phase are indicated by abundant structures, including normal, reverse, and strike?slip faults, as well as folds that affected the Neogene and Late Pleistocene sedimentary deposits. The ductile and brittle deformation resulted mainly from multiple reactivations of E?W, NE?SW and NW?SE trending basement shear zones. The deformation mechanism included distension and compression under a strike?slip regime. Tectonic reactivations even during the late Pleistocene support an unsteady South Atlantic passive continental margin throughout the post?rifting stage. (AU)

• FAPESP's process: 12/06010-5 - Post-rift tectonosedimentary evolution of the Paraíba basin, Northeastern Brazil
• Grantee: Dilce de Fátima Rossetti
• Support Opportunities: Regular Research Grants