Observations sedimentologiques sur les dépôts du Néogène post-nappe dans la région de Moulay Yacoub (NW de Fés- Maroc)

Abstract

Key words: Sedimentology; Tortonian; Lower Pliocene; Paleogeography; Fes; Morocco. Situated on the border of the south-rif furrow and on the oriental extension of the south rifan ridges, the region of Moulay Yacoub (NW of Fes) knew, from Tortonian to lower Pliocene, a monotonous pelagic sedimentation. However, in this essentially marly formation, we can notice at the end of the Tortonian, the apparition of a brief regressive tendency in favour of positive vertical movements. We can notice also the installment of a sedimentation in a shallow sea environment (biocalcarenite formation). This reduction in water depth comes as an efect of the repercussions of tectonic phase of upper Miocene. This phase is responsible for the rise of the south rifan ridges, of prérif and of the close of Mesogea.