Analogical Compression Modeling of the Tunisian Atlas in the Mediterranean Context

Abstract

Tunisia is divided into two major structural domains: the Tellian domain in the north and the Tunisian Atlas further south, both of which belong to the outer zones. In the outer zones, the deformation, dated from the Tortonian to the actual, is characterized by the coexistence of compressive, strike-slip and extensive structures. NE-SW oriented folds and thrusts affect the Mesozoic cover. These structures are more distant towards the south where they interact with two conjugated strike-slip corridors: the fault of Negrine-Tozeur and the N-S axis. The objective of this study is to replace this association of structures in a broader geological context and provide better constraints to deep-seated structures. For this, an analog modeling approach has been adopted. Several experiments were carried out. The results showed that the presence of a level of detachment at the base of the sedimentary series is necessary to correctly represent the compressive structures in central Atlas and extensive in the Tell and the north of the Atlas. Similarly, a free edge perpendicular to the direction of compression allows the formation of strike-slip and conjugate structures similar to the fault of Negrine-Tozeur and the N-S axis.