3D structural modeling and restoration of the Apennine-Maghrebian chain in Sicily: Application for non-cylindrical fold-and-thrust belts

Abstract Thirteen seismic reflection profiles and field observations have been used to build a three-dimensional watertight geological model of the sub-surface architecture of the Trapanese carbonate platform unit of the Apennine-Maghrebian chain in the Mt. Kumeta and Mt. Rocca Busambra (NW Sicily, Italy). Either a single step or a two-step thrust-fault deformation model is acceptable on the basis of seismic interpretation but the integration of 3D model reconstruction and 3D geomechanical restoration, validates only the scenario with a single stage of deformation. The 3D model highlights along strike variation of the structural style for the Trapanese unit where pre-existing discontinuities (e.g. inherited Mesozoic normal faults) played an important role in the preferential occurrence of hinterland verging structures. In detail, backthrusts (N-verging) are dissected by tear faults along the Mt. Kumeta structure whereas an imbricate backthrust system evolves into thrust along the Mt. Rocca Busambra structure. Shortening estimate indicates low amount of internal deformation affecting the carbonate platform unit (