Identification des zones biostratigraphiques méditerranéennes dans le Pliocène du Cap-Bon (Tunisie)

Abstract

The Nabeul-Hammamet series analysis allows to recognize the six biozona known in the Mediterranean realm, as specified by Cita (1975a). These are: the Sphaeroidinellopsis subdehiscens BANNER & BLOW acme biozone equivalent to MPL1; the Globorotalia margaritae margaritae BOLLI & BERMUDEZ interval zone (= MPL2); the Globorotalia margaritae BOLLI & BERMUDEZ , Globorotalia puncticulata (DESHAYES), concurrent range zone (= MPL3); the Sphaeroidinellopsis subdehiscens BANNER & BLOW interval zone (= MPL4); the Globigerinoides elongatus (D’ORBIGNY) interval zone (= MPL5); the Globorotalia inflata (D’ORBIGNY) interval zone (= MPL6). There is no similarity between these biozones and those established by Berggren and al. (1995) for the atlantic and the indo-pacific realms. The MPL1, MPL2, MPL3 and MPL4 zones are especially englobed in argillaceous and yellow sandy lithological units specified in north-eastern Tunisia, such as ‘Argiles des Potiers’, ‘Sables Jaunes de Nabeul’ and ‘Argiles de Sidi Barka’. These units are together equivalent to the Raf-Raf Formation developed towards the North, in the Bizerte area. Besides, the MPL5 and the MPL6 zones are included in sands and sandstones composing the Hammamet unit, equivalent to the Porto-Farina Formation.