Sedimentology and Petrographic Analyses of the Upper Cretaceous and Lower Eocene Carbonate Deposits in the Mateur-Beja Area (NW of Tunisia): The Repercussions of Tectonic Style on Sedimentation
The northwestern Tunisian Mateur-Beja area comprises a thick succession of carbonate rocks belonging to the Late Cretaceous (Abiod Formation) and Early Eocene (BouDabbous Formation and its lateral equivalent) times. Sedimentological and petrographic analyses carried out on these Formations with regard to their palaeogeographic reconstructions. Three sections from the upper Cretaceous deposits and twenty sections from the lower Eocene successions were selected and correlated for this study. The upper Cretaceous Abiod Formation is dominated by foraminiferal biomicrite deposited in upper slope to basin environments, usually influenced by gravity-driven currents. The lower Eocene carbonate successions are characterized by various and diverse facies associations deposited in inner platform to basinal environments. Both carbonate Formations are characterized by lateral variations in thickness and facies, although they were deposited under varying environmental circumstances. Close inspections show that changes in thickness and facies were mainly controlled by sea-floor topography and deposition rates. The conspicuous change in sea-floor topography is well expressed during drastic changes in tectonic style associated with active subsidence, while deposition rates significantly decrease in areas marked by active marine erosional currents. The upper Cretaceous and the lower Eocene carbonate deposits provide useful data about the relationships between tectonic and sedimentation.
KeywordsEocene Cretaceous Carbonates Sedimentology NW Tunisia
- 2.Belghouthi, F.: Les facies des Formations Abiod et El Haria à Mateur: sédimentologie, environnements de dépôts et intérêt pétrolier. Mémoire de Master, Faculté des Sciences de Bizerte, 150 p (2014)Google Scholar
- 3.Burollet, P.F.: Contribution à l’étude stratigraphique de la Tunisie Centrale. Ann. Min. Géol., Tunis 18, 350 p (1956)Google Scholar
- 5.Fournié, D.: Nomenclature lithostratigraphique des séries du Crétacé supérieur au Tertiaire de Tunisie. Bull. Cent. Rech. Expl. Prod. Elf. Aquitaine 2(1), 79–148 (1978)Google Scholar
- 6.Kujawski, H.: Contribution à l’étude géologique de la région des Hédil et du Béjaoua oriental. Ann. Min. Géol. Tunis 24, 484 p (1969)Google Scholar
- 7.Negra, H.: Les dépôts de plate-forme à bassin du Crétacé supérieur en Tunisie centro-septentrionale (Formation Abiod et faciès associés). Stratigraphie, sédimentation, diagénèse et intérêt pétrolier. Thèse doctorat es-sciences, Université Tunis El Manar, Faculté des Sciences de Tunis, 649 p (1994)Google Scholar