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Speculations surround salt deformation in the Mediterranean Basins, both related to the deformation history and the triggers for halokinesis since the onset of the Messinian Salinity Crisis. This work presents a detailed description of the mechanisms driving internal and external deformation of a salt giant from the Levant Basin, offshore Israel. The intrasalt siliciclastic layers generate good internal reflectivity within the Messinian evaporites, allowing a thorough elucidation of the complex evolution and nature of syn-Messinian and post-Messinian structures. We have identified three distinct phases of deformation in the deep basin, based on the orientation, timing, and geometry of their related structures: The first phase is characterized by small-scaled, gravity-driven, contractional faults and folds oriented N-S that have been overprinted by a second syn-Messinian, NW-SE trending, deformation phase affecting the clastic bundles. This latter deformation phase is the cause of truncation of the intrasalt stringers on the intra-Messinian truncation surface. The third deformation phase occurred in the Pleistocene and affected all strata from the Messinian salt to the seabed. This deformational phase produced thrust, strike-slip, and normal faults, but the dominant orientation of the thrust faults and folds is NNW-SSE. Our study demonstrates that the first deformation phase was caused by regional uplift along the Levant margin during the Messinian, the second is a response to basin subsidence toward the Cyprus Arc, also syn-Messinian, and the third phase is likely related to the reorganization of the African-Eurasian plate boundary and activity along the Dead Sea Transform after the Messinian Salinity Crisis.Plain Language Summary A thick body of alternating evaporites and claystones was deposited in the Mediterranean Sea during the infamous Messinian Salinity Crisis, between 5.93 and 5.33 million years ago. This event is in itself poorly understood, as both the cause(s) and the consequence(s) of this crisis is heavily disputed. In this study, we use traditional seismic interpretation as well as geometrical observations and seismic attribute analysis to understand the tectonic movements and how they have generated different fault types in the subsurface of offshore Israel during and after the deposition of the evaporite package. We present three different deformation phases and discuss their possible trigger mechanisms. The good quality of the seismic data used in the study has provided us with excellent examples of thrust, strike-slip, and normal faults in the area. These classical examples offer a clearer picture of the tectonic history of the study area, which has wider application in understanding tectonic histories of many basins worldwide.

Canyons and other sediment conduits are important components of the deep-water environment and are the main pathways for sediment transport from the shelf to the basin floor. Using 3-D and 2-D seismic reflection data, seismic facies and statistical morphometric analyses, this study showed the architectural evolution of five canyons, two slide scars and four gullies on the southern part of the Loppa High, Barents Sea. Morphometric parameters such as thalweg depth (lowest point on a conduit's base), wall depth (middle point), height, width and base width, sinuosity, thalweg gradient, aspect ratio (width/height) and cross-sectional area of the conduits were measured at intervals of 250-m perpendicular to the conduits' pathways. Our results show that the canyons and slide scars in the study area widen down slope, whereas the gullies are narrow and short with uniform widths. The sediment conduits in the study area evolved in three stages. The first stage is correlated with a time when erosion and bypass were dominant in the conduits, and sediment transferred to the basin in the south. The second stage occurred when basin subsidence was prevalent, and a widespread fine-grained sequence was deposited as a drape blanketing the canyons and other conduits. A final stage occurred when uplift and glacial erosion configured the entire southern Loppa High into an area of denudation. Our work demonstrates that the morphometric parameters of the canyons, slide scars and gullies generally have increasing linear trends with down-slope distance, irrespective of their geometries. The morphometric analysis of the sediment conduits in the study area has wider applications for understanding depositional processes, reservoir distribution and petroleum prospectivity in frontier basins.