THE SEDIMENTARY SYSTEM TRACTS ON THE MOROCCAN ATLANTIC MARGIN

The Moroccan Atlantic continental margin constitutes an example of passive margin due to the Atlantic opening between African and North American Plates. Schematically the evolution of this Moroccan Atlantic margin can be subdivided in 5 main steps well identified on the margin of El Jadida. To every step of this evolution, crustal discontinuities of the basement have been rejuvenated giving strike slipe faults playing in transtension or transpression. Such tectonic heredity processes induced the appearence of shearing corridories and a segmentation of the margin. In present paper we try to show how the segmentation of the margin drives to a North-South diversification of the system tracts according the degree of interaction between Tectonics-Eustacy-Climatic variations from Mid-Cretaceous to Present Time. Thanks to a collaboration with the ONAREP , it has been possible to study seismic profiles to compare the evolution in space and during time of the sedimentary system tracts in various segments of the Moroccan Atlantic Margin. Four target-zones have been selected: - in the north, the continental platform near Rabat connected with of the relatively stable Moroccan meseta. - in the center, in the Essaouira and Agadir platforms, mobile zonescorresponding to the Western end of the wrench faulting complex of the Moroccan High Atlas . - to the South, the platform of the Tarfaya basin associated with the Saharian Platform. We present here the first results of this comparison between the main types of segments.