Late Triassic–early Jurassic block tilting along E–W faults, in southern Tunisia: New interpretation of the Tebaga of Medenine

The Tebaga of Medenine is a puzzling structure situated at the northern edge of the Jeffara plain in southern Tunisia. It presents the unique outcropping marine Permian sequence in Africa as well as spectacular angular unconformities related to Mesozoic tectono-sedimentary events. Many hypotheses have been proposed to explain this structure but some questions still remain. We present the result of an integrated study of the Mesozoic tectonic evolution of the region, based on new field work and a reassessment of some subsurface data. We propose a new structural hypothesis in which the Tebaga of Medenine is interpreted as resulting from large scale block tilting, mainly controlled by inherited E–W major faults, the Azizia fault system. These E–W faults running along the Jeffara plain may represent inherited structural features in relation with deep faulting in the Paleozoic substratum. This rifting occurring during late Triassic up to the end of early Jurassic, is finally integrated in the general frame of the East Mediterranean.