الأطلس الكبير
The western High Atlas was part of the Atlantic Jurassic passive margin and is separated from the central and eastern High Atlas by the Paleozoic Massif, an area of pre-Mesozoic basement exposures located south of Marrakesh. The central and eastern High Atlas basin developed as a multiphase rift system opened toward the east by two major rift episodes occurring during Middle-Late Triassic and Early Jurassic (late Sinemurian and Pliensbachian. At present, the central High Atlas is characterized by a folded domain that is dominated by NE-SW striking structural highs or ridges separating elongated and wide synclines filled by Early and Middle Jurassic sediments.