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Abstract

Sedimentary basins along the SW African margin deliver information about processes, which occurred in the past and serve as a good starting point for reconstructing the margin’s evolution. By integrating detailed information on the present-day configuration of the SW African margin into a 3D thermo-mechanical forward modeling framework, we attempt a margin-wide reconstruction of its subsidence history since its onset during breakup. The 3D forward modeling approach as applied on the SW African margin area makes use of the coupling between thermal relaxation of the lithosphere and flexural isostatic balance in response to sediment deposition and build-up of thermal stresses during lithosphere cooling. On the one hand, our results provide useful information about the behavior of the lithosphere during breakup and the subsequent post-rift phase. On the other hand, restored paleobathymetries for specific time intervals during the post-rift evolution give evidence for possible uplift events superposed on the long-term subsidence history of the margin. Restored paleobathymetries are in agreement with conclusions derived from former studies and provided strong indications for the presence of a rather heterogeneous crustal configuration of the margin marked by a mechanical decoupling of the upper and lower crustal domains during most of the rifting phase.