Structure and stratigraphy of Mazagan (El Jadida) Escarpment (West Morocco): first results of Cyamaz diving campaign

Nature 305, 698 - 701 (20 October 1983); doi:10.1038/305698a0    VOIR  /  http://www.nature.com/nature/journal/v305/n5936/abs/305698a0.html;jsessionid=E0DD391905072B753A1D106418A96982

Structure and stratigraphy of Mazagan (El Jadida) Escarpment (West Morocco): first results of Cyamaz diving campaign

^* & Jean-Marie  & Ulrich  & Bernard  & Pavel  & Michel  & Hans  & Michel  & Yves  & Etienne  & Torsten AuzendeVon RadDiju-DuvalCepekCousinDostmanJaffrezoLancelotRuellanSteiger^*

The Mazagan Escarpment is located about 200 km south-west of Casablanca in the central Atlantic (Fig. 1). It constitutes an almost 3,000m high cliff between the Mazagan Plateau and the Seine Abyssal Plain. Because of its steepness, the Mazagan Escarpment provides an exceptional opportunity to study the Mesozoic to Palaeogene stratigraphy, palaeoenvironment and subsidence history of a nearly sediment-free external carbonate platform, exposing the late Jurassic and Cretaceous continental margin sediments of the Atlantic Ocean. Reconstructions of the central Atlantic at the end of the Liassic¹ show the location of the Mazagan Escarpment between the African continent and its thinned, stretched margin, where evaporitic series have been deposited²⁻⁴. For several years, many cruises have been conducted in the Mazagan area. Some of the data obtained have been published^2,5−7. Before IPOD Leg 79, two DSDP sites (370, 416) have been drilled in the deep Moroccan Basin^8,9. Results of Leg 79³ demonstrate the variety of environments during the Jurassic, but also a certain episodicity in the defacing of the scarp up to Neogene times. The Cyamaz diving cruise has been prepared by a bathymetrie survey using the multibeam echosounder 'Seabeam' (Fig. 1)¹⁰.

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