Early evolution of the South Atlantic Ocean: role of the rifting episode.

Abstract

For the South Atlantic Ocean, the rifting period began during the Oxfordian-Kimmeridgian and ended progressively from the Hauterivian near the Agulhas Plateau to the early Albian in the vicinity of the Niger Delta. The Walvis Ridge/Rio Grande Rise system acted as a dam to marine incursions into the Angolan and Brazilian basins until the mid-Aptian. The Parana Basin and the Torres syncline (Brazil), the eastern Walvis Ridge and the Kaokoveld region (Namibia) form an originally continuous volcanic terrane created in the continental domain during the Late Jurassic-Early Cretaceous by tensional processes. This terrane corresponds to a failed rift arm extending into South America and involving about 100 km of extension. These factors provide new constraints for the early kinematic evolution of the South Atlantic.-from Authors