Syn-sedimentary tectonics in central Tunisia (Jebel Mrhila area) during the Aptian-Albian

The important sedimentary gaps the variations of thicknesses and facies which characterize the Aptian-Albian series in the J. Mrhila area, are linked, at least partly, to the action of two tectonic features. 1. The Mrhila-Cherichira fault, with a NNE-SSW direction, is responsible for the collapse of the area located north of this major accident; the southwards tilt of this area made the accumulation of very thick marine sediments possible, during Clansayesian to Late Albian time, at Koudiat El Beida (KEB) and in Bled El Gouna 1 (BEG.1) wells. These sediments do not occur in the uplifted area, south of the fault. 2. The second feature, corresponding to the Sbiba fault, with a N 140 direction, had as effect, the reduction of the Albian series within the Tiouacha 1 (Ti.1) boring. This variation is significant, even if it is, by far, less important than that occurring on both sides of the major NNE-SSW fault. It seems that this Sbiba fault played a role in Clansaysian to Upper-Albian sedimentation, which resulted in the formation of a losangic basin. (C) Academie des sciences/Elsevier, Paris.