The Jurassic-Cretaceous red layers of the Moroccan Central High Atlas

This work presents a lithostratigraphic, sedimentological and structural-geodynamic study of the Jurassic-Cretaceous 'red beds' of the Moroccan Central High Atlas. Ten detailed sections taken in different regions of the domain show increasingly coarse deposits going from the center towards the edges of the basin. The total thicknesses of the series vary from 170 m in the west to about 1470 m in the center of the domain. This series contains traces and bones of vertebrates and remains of plants as well as ostracods and charophytes. These deposits changes in their depositional environment between the Bathonian to the Infra-Cenomanian. During their deposition, tectonics coupled with magmatism, caused differential local subsidence which was at the origin of notable variations in the thickness and facies of the series from one place to another. In the Cenomanian-Turonian, the Thetys, coming from the East and the North-East, penetrated into the Atlas domain to draw a paleoshore around the central part of the basin.