The Kelaat Mgouna Neoproterozoic Group (ca 800 Ma) consists of turbiditic siliciclastic deposits and submarine interbedded basaltic lavas. The sedimentological features of the facies, their sequential organization and their vertical association are indicative of an under-water foot slope depositional environment. The petrographical and morphological analyses of detrital material indicate a proximal continental provenance. The geochemical features of basalts correspond to continental tholeiites. The Kelaat Mgouna Group is interpreted as deposited in an opening basin during the initial stage of the pre-Pan-African extension.