The Neogene-Quaternary Taza-Guercif Basin, northern Morocco, is one of a number of remnants of the basinal "South Rifean Corridor" which connected the Atlantic Ocean to the Mediterranean Sea during the Miocene. The basin has a hybrid structure because its development was influenced both by the Rif orogenic belt to the north and NW and the Middle Atlas Shear Zone to the SW. Stratigraphic and structural studies have been carried out in the basin. The recognition of major unconformities, the distribution in time and space of sedimentary facies, and the areal distribution of deformation structures at various scales have been integrated to reconstruct the tectono-sedimentary evolution of the basin beginning in the the Tortonian (late Miocene). This evolution is related to outward migration of the Rif deformation front and to tectonic activity in the Middle Atlas Shear Zone. This stud highlights the role played by the Middle Atlas Shear Zone as a first-order element in the evolution of the Rif belt and of the Moroccan Meseta in relation to the African Plate.