In particular, seismic reflection surveys imaged and constrained only its offshore segments 10, 12. Besides the importance of LRB in the tectonic evolution of the area and its present-day activity, the knowledge of its subsurface geometry is poor. LRB also represents a significant source of seismic hazard for the region hosting several historically active faults 10, 11. The Lebanon restraining bend (LRB) is one of the best examples of transpressive structures worldwide. Many applications, such as fault-based seismic hazard assessment, are influenced by the knowledge of fault 3D geometries at depth 8, 9, but information on the down-dip fault geometries are often lacking, and indirect while robust estimates are needed. In particular, all structures are characterised by uplifted pop-up structures with faults converging with increasing depth. These authors compare results from analogue models to several natural cases showing important similarities between both examples. Scaled analogue modelling has proved to be a powerful tool in understanding the geometries and kinematics of complex 3D structures in restraining bend structures 6, 7. Such geometry allows the wrench component of movement to have significant uplift rates due to colliding blocks 5. Transpressional systems may extend to deep crustal levels as nearly vertical structures. Strike-slip faults pose major challenges in understanding their structural setting and evolution due to closely-spaced fault planes with sub-vertical attitudes and non-planar geometries along strike. Transcurrent faulting affects many parts of the Earth's lithosphere and occasionally results in prominent topographic expressions 1, 2, 3, 4. We also propose recent Neogene tectonic evolution of the region based on our modelling and integrated with published U/Pb dating of fault zones and tectonostratigraphic evidence. Furthermore, this simulation supports the hypothesis that the restraining bend of the DST formed in the widespread crustal weakness zone developed in the Late Jurassic to Early Createceous. Lebanon, Anti-Lebanon and Palmyrides structures. Our results, validated by structural evidences, highlight that various structural styles lead to formation of Mt. We propose an original approach, which uses implementation of well-known fault geometries, surface and subsurface data, for structural validation in the complex strike-slip domain. The simulation accurately predicts the shape and magnitude of positive and negative topographic changes and fault slip directions throughout the study area. Using a boundary element method, we modelled fault deformation response to the regional stress field. We built a 3D geometrical model of the fault surfaces based on previously studied natural examples, structural maps, satellite images, DEM interpretation and experimental analogue models of restraining bend or transpressional structures. It consists of two mountain ranges: the Mount Lebanon and the Anti-Lebanon ranges. Lebanon restraining bend represents the most prominent topographic transpressional feature along the Dead Sea Transform (DST). This study adopts an approach based on the boundary element method at the regional scale to test the structural interpretation of a complex transpressional mountain range. Most of the methodologies used to validate complex strike-slip structures mainly rely on comparison with other well-known geological features or analogue laboratory models.
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