Fault — Dissolution front relations and the Dead Sea sinkhole problem

Abstract

There are two conflicting models of sinkhole development along the Dead Sea (DS). The first one considers structural control on sinkholes, constraining them to tectonic lineaments. This hypothesis is based on seismic reflection studies suggesting that sinkholes are the surface manifestations of active neotectonic faults that may serve as conduits for under-saturated groundwater, enabling its access across aquiclude layers. Another hypothesis, based on results of multidisciplinary geophysical studies, considers the salt edge dissolution front as the major site of sinkhole formation. This hypothesis associates sinkholes with karstification of the salt edge by deep and shallow undersaturated groundwater. Our recent seismic reflection and surface wave studies suggest that salt formed along the active neotectonic faults. Sinkholes form in a narrow strip (60–100m wide) along a paleo-shoreline constrained by faults and alluvial fans which determined the edge of the salt layer. This scenario reconciles the two major competing frameworks for sinkhole formation.