Cloud Publications International Journal of Advanced Earth Science and Engineering 2017, Volume 6, Issue 1, pp. 596-621 ISSN: 2320–3609, Crossref: 10.23953/cloud.ijaese.330 ____________________________________________________________________________________________________ _____ Early Mesozoic Detrital and Evaporitic Syn-Rift Series of Mohammedia-Benslimane-ElGara-Berrechid Basin (Meseta, Morocco): Sedimentary and Palaeoenvironmental Evolution and Comparison with Neighboring Basins Abdelkrim Afenzar, Rachid Essamoud Dynamics of Sedimentary Basins and Geological Correlations Laboratory, Faculty of Sciences, Ben M’Sik, Hassan II University of Casablanca, B.P. 7955, Sidi Othmane, Casablanca, Morocco Publication Date: 20 December 2017 DOI: https://doi.org/10.23953/cloud.ijaese.330 Copyright © 2017. Abdelkrim Afenzar, Rachid Essamoud. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract The Triassic basin of Mohammedia-Benslimane-ElGara-Berrechid contains a sedimentary series consisting of a sandy-conglomeratic formation (Formation A) at the base, surmounted by an argillaceous-saliferous formation (Formation B), the whole being capped by Late Triassic-Early Jurassic basalts. Formation (A) is formed by conglomeratic facies with alternations of sandstone in the middle and top of the formation. Formation (B) is subdivided into two members: (1) mudstone- siltstone member formed by alternations of mudstone and siltstone facies; and an argillaceous- saliferous member (2) composed by mudstone and evaporite facies. Sedimentary analysis carried out on more than ten outcrops and on four cores sample that have identified fifteen types of facies and seven architectural element and facies associations. It leads to the reconstruction of depositional environments during the Upper Triassic in the basin. Also, this work allowed a comparison of the sedimentary series of this basin with those of the other basins of the Moroccan Atlantic margin on one side and the North-east American margin on the other side. Keywords Architectural element; Comparison; Depositional environment; Evaporites; Facies; Triassic 1. Introduction The Mohammedia-Benslimane-ElGara-Berrechid (MBEB) basin is considered among the most important Triassic basins in Morocco and even in the world. This importance is reflected in its role in understanding the geodynamic and paleogeographic history of the Central Atlantic domain during the Triassic time. Most of these Triassic basins belonging to the Central Atlantic domain show a similar sedimentological evolution. They are dominated by continental deposits (Withjack et al., 1998; Leleu and Hartley, 2010; Withjack et al., 2012; Leleu et al., 2016). The sedimentary filling of these basins is strongly diachronous, and the timing and duration of the deposition phase vary from one basin to another (Leleu et al., 2016). Research Article