Présence de chitinozoaires ordoviciens et dévoniens dans la boutonnière des Zekkara, région d’Oujda (Maroc oriental) [Occurrence of Ordovician and Devonian chitinozoa in the Zekkara’s inlier, Oujda area (Eastern Morocco)]

Paleozoic rocks are represented from the Oujda area (NE Morocco). These strata, surrounded by Cenozoic deposits, occur in the Zekkara’s inlier. The investigated section corresponds to a complex succession of shales and mudstones including several chaotic levels which have been interpreted as gravity-settled deposits (olistostromes). The age of the whole sequence has long been debated.

The aim of the present study, based on chitinozoa, is to improve recent data provided by acritarchs. A fairly closely spaced sampling is realized exclusively in the shales and siltstones in order to get an accurate distribution of the chitinozoa. Most of the samples yield Early Llanvirn taxa, but a few Upper Ordovician and Givetian chitinozoan assemblages are also recorded. Obviously, no reworked taxa occur in our material. Consequently, the chitinozoa provide the age of the sedimentation.