The sinkholes, also found on the Jordanian side of the sea, are the result of the Dead Sea having shrunk by a third since the 1960s when Israel and Jordan built plants to divert water flowing through its main tributary, the Jordan River. Eli Raz, Geologist: "Due to the rapid drop, the ground water are now facing with the salt rock and the salt rock is undergoing a very rapid dissolution. Cavities are formed inside and eventually the surface collapse down to the cavities and these are the sinkholes."
The holes form when a subterranean salt layer that once bordered the sea is dissolved by underground fresh water that follows the receding Dead Sea waters. Sinkholes around the Dead Sea pose a hazard to tourists and the environment alike. The danger may only get worse, and geologists hope to map problem areas to help protect the public. National Geographic.com