New paleontological and geological data about Jbel Tselfat (Late Cretaceous of Morocco)

The ridge of Jbel Tselfat is located at about 30 km north of Meknes (Morocco). It is composed of a Jurassic core surrounded by Miocene levels. Some fossiliferous outcrops of black shales, dated from Late Cretaceous, are present in a thrust sheet in the north and east. Jbel Tselfat was carefully explored by the French paleontologist Arambourg, between 1934 and 1954, and a large amount of actinopterygian fishes has been collected from two localities, Ain el Kerma and Sigda. In the framework of the ongoing collaborative Franco-Moroccan research project, a fieldwork has been carried out in autumn 2008 in three sites near Ain el Kerma and in Sigda. An abundant material has been collected. This new fish assemblage is dominated by dercetids, but yielded also pycnodonts, clupavids, protostomiids and acanthopterygians. Other taxa never observed until now in this locality have been found associated with fishes, such as one ammonite and several plant remains. Ongoing geological studies and thin sections analysis allow a better understanding of geological and paleoenvironmental contexts of these vertebrate bearing strata of Jbel Tselfat. They show a deep and quiet marine paleoenvironment, probably close to the coast, in good agreement with Arambourg's ideas. Comparison with other 'mid-Cretaceous' fossil fish localities permits to review the dating of Jbel Tselfat and considers it close to the Cenomanian-Turonian boundary. The deposition of black shales is possibly associated to the Oceanic Anoxic Event