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

Abstract

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, Aïn 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 Aïn 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 2.

Keywords:

• fossil fishes
• Morocco
• black shales
• Cenomanian–Turonian boundary
• paleoenvironment

Acknowledgements

This work was a contribution to the first International Congress on North African Vertebrate Paleontology, 25–27 May 2009, Marrakesh, Morocco. This fieldwork was financed by the UMR 7207 of CNRS and the Département Histoire de la Terre, MNHN, France, with the participation of the Faculté des Sciences Semlalia, Marrakesh (FSSM) and the Faculty Dhar el Mahraz, Fez. Authors want to thank Lionel Cavin (Muséum d'Histoire Naturelle de Genève, Switzerland) for his comments and reviews on the manuscript, Marie-Béatrice Forel (Univ. Pierre et Marie Curie, UMR 7207 CNRS, Paris) for her useful discussion and English improvement, Siham Assouad (Fac. Dhar el Mahraz, Fez), Annachiara Bartolini, Sylvain Charbonnier, Jocelyn Falconnet, Philippe Janvier (MNHN, UMR 7207 CNRS), Delphine Desmares (Univ. Pierre et Marie Curie, UMR 7207 CNRS, Paris), Mohssine Ettachfini, Najat Feddi, Nour-Eddine Jalil (FSSM, Marrakesh), Johan Schnyder (Univ. Pierre et Marie Curie, Paris), Didier Dutheil and Guillaume Suan for their useful comments. Thin sections have been realised by Michel Lemoine and Lilian Cazes (MNHN, UMR 7207 CNRS). Some photographs have been taken by Christian Lemzaouda (MNHN, UMR 7207 CNRS). Thanks to Mohamed Sellam for his hospitality. This mission was possible with authorisation and support of the Ministère de l'Energie et des Mines, Rabat, Morocco.