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We combine geological and geophysical observations made along the margin between the Arabian plate and Sinai sub-plate to investigate the style and sequence of deformation associated with motion along the Dead Sea Fault (DSF). Our analysis focuses on one of the youngest rock units-the Pleistocene Hazbani Basalt. Integration of field mapping, K-Ar dating, and interpretation of high-resolution seismic reflection profiles yields a map of the top surface of the Hazbani Basalt, which highlights the architecture of faulting and folding. Results attest to a dominance of both contractional structures and strike-slip faulting along the northwestern rim of the Hula basin. Our new findings show how a series of faults extend from within the boundaries of an extensional basin and beyond its margins, and are associated with the formation of positive flower structures. The structural analysis provides evidence for a transition from an early (pre-Pleistocene) phase of almost pure strike-slip to a late (Pleistocene) phase of convergent strike-slip faulting. Many of the faults investigated in this study displace the Pleistocene Hazbani Basalt and the overlying sediments and should thus be considered as potential active faults for seismic hazard assessments.

The formation of sinkholes along the Dead Sea is caused by the rapid decline of the Dead Sea level, as a possible result of human extensive activity. According to one of the geological models, the sinkholes in several sites are clustered along a narrow coastal strip developing along lineaments representing faults in NNW direction. In order to understand the relationship between a developing sinkhole and its tectonic environment, a high-resolution (HR) three-dimensional (3D) seismic reflection survey was carried out at the western shoreline of the Dead Sea. A recently developed 3D imaging approach was applied to this 3D dataset. Imaging of subsurface is performed by a spatial summation of seismic waves along time surfaces using recently proposed multipath summation with proper weights. The multipath summation is performed by stacking the target waves along all possible time surfaces having a common apex at the given point. This approach does not require any explicit information on parameters since the involved multipath summation is performed for all possible parameters values within a wide specified range. The results from processed 3D time volume show subhorizontal coherent reflectors at approximate depth of 50-80 m which incline on closer location to the exposed sinkhole and suggest a possible linkage between revealed fault and the sinkholes.

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