Late Barremian eustacy and tectonism in the western High Atlas (Essaouira-Agadir Basin), Morocco

The Barremian-Aptian interval is considered a turning point in the extensional evolution of the passive Atlantic margin of Morocco. The biostratigraphy and sedimentology study of the coarse-grained clastic deposits of the Essaouira-Agadir Basin (Bouzergoun Fm) indicates that they are entirely late Barremian (Sartousiana p.p. to Sarasini p.p. Zones) and suggests that most of them were deposited in a shallow marine environment, locally impacted by substantial fluvial influences. Facies evolution and the identification of discontinuity surfaces subdivide the unit into seven depositional sequences, two of which are marked by coarse-grained deposits and numerous indications of synsedimentary instability, and are interpreted as tectonically enhanced. These late Barremian tectonic events are interpreted as related to the abrupt uplift of the West Moroccan Arch, a long-lived, NNE-trending positive structure, located east of the Essaouira-Agadir Basin.