Cretaceous geology and stratigraphy of Morocco and adjacent coastal basins

Abstract

The Cretaceous marine sediments of Morocco and adjacent coastal basins provide an outstanding archive of environmental diversity from extended shelf seas and marginal basins along the Atlantic and Tethyan margins to deep oceanic basins of the western Tethys and eastern Atlantic Ocean. The geological highlights of Morocco's fascinating landscape include records of Lower Cretaceous Tethyan marginal and deep water clastic sequences in the Rif mountain chain (submarine fan systems of the Massylian and Mauretanian flysch units), as well as siliciclastic sedimentary sequences in subsiding coastal basins (TanTan Delta), which extend offshore along the Northwest African Atlantic margin. Vestiges of the Aptian to Turonian greenhouse climate, sea-level highstands and oceanic anoxic events are exceptionally well-preserved in Tethyan marginal and deep water sedimentary successions of the Rif, in Atlantic coastal basins and as transgressive pulses on the Moroccan Meseta, Sahara platform and High Atlas rift system. Furthermore, sedimentary expressions of the tectonic movements between the African and European plates associated with the end Cretaceous climate and sea-level changes are documented in the Rif mountain chain, in coastal basins, and in the massive marginal marine phosphorite sedimentation in the Middle and High Atlas, on the Moroccan Meseta and Sahara platform. In this review we provide a brief history of geological investigations and an overview of Cretaceous sedimentary archives, as well as a selection of research highlights and outstanding questions concerning the Cretaceous system in Morocco. The Cretaceous sedimentary archives from Morocco and adjacent coastal basins still retain untapped potential to further contribute to our understanding of global eustatic sea-level changes and the response of the oceans and marine biota in upwelling driven oxygen minimum zones under greenhouse climate conditions.