Criteria to discriminate between different models of thrust ramping in gravity-driven fold and thrust systems

Although most models of thrusting assume that the hangingwall is actively displaced up thrust ramp while footwall remains passive, it has been suggested this could be an oversimplification and may also deform. Despite this, there are relatively few detailed investigations thrusts where deformed, perhaps reflecting issues with space accommodation if moves downwards to deeper levels. Furthermore, such studies deeply buried, otherwise more likely rise simply uplift surface. Using examples from gravity-driven fold systems developed in unlithified late Pleistocene sediments around Dead Sea Basin, we investigate pristine geometries unaffected by later compaction deformation establish two end-member overthrust underthrust development. During overthrusting, uplifted marker beds remain at or above regional elevation, whereas ramps depressed deflected below regional. The greatest displacement generally develops low down decreases upwards, larger displacements form high reduce downwards. reduction marked decreasing dips, increases dips ramps. Fault propagation folding creates antiforms ramps, synforms develop effect sequences cut-offs thinned (stretch <1) (stretch>1). Not all follow these mixed ‘wedge’ which both deformed varying degrees. Underthrust failure initiates competent units higher deforming sequence, then propagates towards underlying potential detachments. Downward accommodated weak absorb differential vertical resulting 50% thinning some cases. A consequence underthrusting crests structures tend same elevation therefore unable build significant topography bathymetry on sediment-water interface, thereby rendering critical taper less relevance. Significant facilitate expulsion fluids drive further complicate use area balancing techniques during restoration systems. • Gravity-driven (FATS) mass transport deposits (MTDs) examined. Criteria distinguish overthrusting established. We describe underthrusts for first time FATS within MTDs. Underthrusting compaction. Underthrusts lack render relevant