The Salt Formation Edge as a Major Indicator of the Sinkhole Hazard in the Dead Sea Western Coast

Since last 15 years, hundreds of sinkholes have appeared in alluvial fans and other unconsolidated sediments along the coastlines of the Dead Sea (DS) in Israel and Jordan. It causes major economical and social problems. In the framework of NATO Science for Peace Project SfP 981128, a field study in the Dead Sea coastal area of Israel has been performed. One of the main objectives of the study was the salt layer mapping using the seismic refraction method. Geophysical results reveal a salt layer located at the depth of 20 to 50 m. Six sinkhole hazardous sites have been investigated. It was found that at all six sites sinkholes are arranged along the western edge of the salt formation. Visual observations of sinkholes appearance show that the process is expanding from the southern part of the Dead Sea shore to the north. Spreading out of sinkholes in the transverse to the salt edge direction was not observed. Based on our results, we can recommend the GRM technique as a tool for the sinkhole hazard assessment in the Dead Sea western coastal area.