Salt Tectonics of the Offshore Tarfaya Basin, NW Africa

Abstract

Salt tectonics has a critical role in basin analysis. However, research integrating a salt tectonics perspective is scarce in regional studies along the NW Africa Atlantic passive margin. This study focuses on regional interpretation of unpublished 3D/2D seismic data from the offshore Tarfaya Basin to explore the main controlling factors that influenced its evolution from a salt tectonics approach. Tarfaya Basin constitutes a rifted passive margin developed over thinned continental crust located at the Atlantic margin of southwestern Morocco, east from Fuerteventura and Lanzarote islands. The main factors that conditioned the basin's evolution can be summarized as follows: (1) irregular thickness and distribution of the original salt layer (Upper Triassic); (2) basin tilting caused by thermal subsidence and initial sea-floor spreading phases (Lower Jurassic); (3) development of a mainly carbonatic shelf wedge related to the onset of the incipient Atlantic passive margin (Upper Jurassic); (4) progradation of the Tan Tan delta complex (Lower Cretaceous); (5) compression related to the convergence between African and Eurasian plates (Upper Cretaceous - Recent).