Stratigraphic correlation between the Numidian formation (North Tunisia) and Oligo-Miocene deposits of central Tunisia.

Sedimentologicand biostratigraphic studies from the Oligocene to Middle Miocene deposits, exposed in central and north Tunisia, lead to a sequence stratigraphy subdivision of these deposits into several third order depositional sequences. The north-south correlations show that the detrital quartz pebbles appeared much later in central Tunisia (within a 'fluvial-deltaic' complex), than in the Numidian in northern Tunisia (characterised by deep submarine channels filled with high density turbidites). Thus, in central Tunisia, the Fortuna Formation (from Rupelian to Lower Burdigalian) could not have supplied Numidian sands from the Saharan region as has been proposed by several authors. (C) 2000 Academie des sciences/ Editions scientifiques et medicales Elsevier SAS.