CONTRIBUTION TO A NEW STRATIGRAPHIC FRAME WORK OF THE LITTORAL QUATERNARY FORMATIONS OF THE CASABLANCA REGION (MOROCCO)

Littoral deposits of the Casablanca region has provided most of the st ratotypes for the Maghreb sequence of Quaternary marine ''stages''. Pa rt of these deposits is here the subject of a new lithostratigraphic a pproach based on sequential analysis. The formations we have identifie d all correspond to regressive sequences indicating a succession of up per shoreface (sometimes), then foreshore, then backshore, then eolian dune depositional environments. Moreover, the results show that 1) fo rmations not recognized before are interstratified between successive ''stages'' from the earlier sequence (e. g. Maarifian and Anfatian), 2 ) deposits attributed to different ''stages'' (Maarifian, Amirian) now indisputably appear to be from the same formation and 3) correlations made previously between certain regional deposits cannot now be retai ned. Thus, the classical chrono-stratigraphic framework so far used in Maghreb must be abandoned.