The world’s longest marlstone cave, with an overall length of a mile, was recently found in the Dead Sea area in southern Israel by cave researchers, led by a team from the Hebrew University.
“The discovery of cave fields on the Dead Sea coast is one of the most significant and dramatic discoveries in fieldwork in Israeli caves in recent years,” the researchers declared.
Natural caves in the marl rocks on the Dead Sea coast have been known for decades, mainly because the famous Qumran scrolls were discovered there.
Since the discovery of the Qumran caves, several other marl caves have been discovered, but their finding was considered episodic and not particularly significant.
As part of a comprehensive study recently conducted by an extensive team of researchers from the Center for Cave Research at the Hebrew University, the Cave Lovers Club, the Department of Earth and Environmental Sciences at Ben-Gurion University and the Israel Geological Institute, three large clusters containing thousands of marl caves were discovered, including the longest and most developed of their kind in the world.
The most developed cave to date has been discovered in the southern Dead Sea when surveyors were on their way to explore another site in the area.
“On the way to the destination, we noticed a small opening in the wall of a deep marl canyon. We entered intrigued, to see if there was any space beyond the opening. Unprepared and with only basic gear we found ourselves after six hours of crawling as we tried to climb through vertical shafts. We did not prepare ourselves for such a cave because we did not know that there are so many developed marl caves,” said Boaz Langford, a geology student at the Institute of Earth Sciences at the Hebrew University and a cave explorer at the Cave Research Center.
After investigators documented the cave and tried to calculate its dimensions, it was found to be 1,380 meters long.
The marlstone caves are formed by the drift of the rock by the streams that cross the area. This type of cave is called a drift cave and according to what is known from around the world, they drift and disappear within years to decades, and they usually do not create developed spaces.
For comparison, the second-longest drift cave in the world today, according to information published on the online list of the largest caves in the world, is the “B&B – bed & breakfast”, located in San Juan County in northeastern New Mexico in the US. The length of the cave is 821 m.
Only recently, since the beginning of the systematic documentation of marl caves in the Dead Sea basin, a number of large caves have been discovered, and today, three of the 10 longest drift caves in the world are situated near the Dead Sea.
“To the best of our knowledge, the marl cave we found is the longest in the world. We would be very happy to keep up to date with foreign teams elsewhere in the world if known otherwise,” said Prof. Amos Frumkin of the Institute of Earth Sciences at the Hebrew University and director of the Cave Research Center.
The new cave found in the Dead Sea shows the enormous potential for finding additional long marl caves in this area. Examining aerial photographs of the cave area, one can get the impression that this cave is not an unusual phenomenon in the area, with all the runoff on the surface draining into the subsoil into long flow channels.
The development of these flow channels has been studied in the study and appears to be related to surface conditions including unbound rock, low surface slopes and subterranean conductivity along cracks.
Dr. Amit Moshkin of the Israel Geological Institute noted that “similar surface patterns have been found in certain areas on Mars in the past – a similarity that suggests the possibility of finding similar subterranean spaces on Mars.”
Assaf Geyer, a doctoral student at the University of Haifa, believes that the exposure of other caves in the area is just at its beginning.
“Understanding the extent of the phenomenon and discovering the cave fields on the Dead Sea coast is one of the most significant and dramatic discoveries in fieldwork in Israeli caves in recent years. We understand that there is a lot of work in the field for us and future generations. Decades will pass until all the caves in the area are fully documented. The discovery of the caves also opens new directions for research in everything related to landscape design, the tectonic development of the area and human activity in antiquity.”
