Early Cretaceous marine incursions into South Atlantic rift basins originated from the south

Abstract The breakup of Gondwana resulted in sedimentary deposits recording lacustrine to marine environmental transitions the South Atlantic rift basins during Early Cretaceous. Currently, ambiguity pervades our understanding timing and orientation initial seawater incursion. Here we investigated hydrocarbon biomarkers sediments from two drill cores off West Africa with stratigraphic coverage Berriasian-Barremian Albian. Based on that can distinguish non-marine marine-influenced settings, influx occurred through southern entrance across Rio Grande Rise-Walvis Ridge early Aptian stage. Transitional conditions prevailed stage as incursion induced microbial community reorganization until Albian when fully prevailed. Overall, results this study are valuable deciphering final opening Ocean, fulfilling global comparison paleoenvironments, facilitating future petroleum exploration along conjugate margins.