Seismostratigraphic Characterization of the Rharb Basin’s Post-nappe Series (N-W Morocco)

The Rharb basin is a tectonically active zone between the Rifaine fold and thrust belt and the western Moroccan Meseta. It is made up of a set of structural Miocene tectonostratigraphic units witch evolution is nowadays debated. Compilation of an array of industrial seismic profiles calibrated with well-log data enables us to establish the sismostratigraphic framework of the Miocene units. The new three-dimensional model of the substratum (nappe prérifaine) of the Rharb basin shows an arcuate and diapiric-like structure linked to the southwestern extrusion of the prerifaine nappe. The most associated deformations are normal extensional faults with a detachment surface located mostly on the “prérifaine” layer hinges. The identified sismosequences are controlled by prerifaine nappe extrusion and Miocene/Plio-quaternary relative sea-level fall.