A rumble was felt from Iraq to Sicily * This earthquake did not occur in Turkey but in northern Israel, in the year 1202 and there were quite a few like it. Once a week, a delegation of geologists leaves from Jerusalem, mounted on jeeps, for tours around the country. They are looking for any trace of evidence of past earthquakes
Tamara Traubman
In the last seventy years, there has been only one strong earthquake in the region of Israel - in 1995. Fortunately, its epicenter was in the middle of the sea, about 100 kilometers south of Eilat, and most of the damage amounted to a few broken windows in the hotels in the city. This is how the mistaken impression was created that as far as natural disasters are concerned, the Israeli soil is calm and earthquakes are not a real danger. But the truth that emerges from the pages of history is different: Israel is actually an area prone to earthquakes, even very strong ones. Throughout history, there have been dozens of powerful earthquakes in the area, which have resulted in thousands of deaths. The epicenters of the tremors were along the Dead Sea rift, known as the Syrian-African rift.
"We are sitting on a fault no less dangerous than the fault in the Sea of Marmara (where the last earthquake occurred in Turkey, 2,000), but this information is not available to the general public," says Dr. Roni Allenblum, a historian and geologist from the Hebrew University. "Where there was an earthquake in the past, there will be an earthquake in the future," says geologist Dr. Shmuel Marko, from the Geological Institute in Jerusalem. "All the ancient cities in Israel, such as Jerusalem, Beit Shean, Safed and Tiberias, have been damaged by earthquakes in the last XNUMX years at least three to five times, and when I say damaged I mean significant destruction and many casualties. An earthquake will hit all these places again in the future, the only question is when."
Not much is known about earthquakes in Israel. Only in the early 80s did they begin to set up a network of seismographic detectors to collect data about geological activities in the area. Before that, only one or two seismographs were used. The 20 years during which this monitoring is carried out is considered a tiny window in geological terms, so it is difficult to build an overall picture of future earthquakes from the data collected so far. "Our situation is worse than that of Turkey," says Marko. "There at least they clearly knew that there was going to be an earthquake and where it would be. We don't even have that knowledge here."
Since the accumulated information about the present is not enough to predict the
In the future, geologists turn to gather more information from the past. And so, once a week, a delegation of geologists leaves from Jerusalem, mounted on jeeps, for tours around the country. They are looking for any trace of evidence of earthquakes that hit the area hundreds and even thousands of years ago. The journey into the intricacies of Israel's geological history will allow them to anticipate where the next earthquake will occur, as well as estimate what its strength will be and when it is more or less expected to occur.
The objects of their research are archaeological remains of buildings,
Various signs on the ground and letters in Latin, Arabic and Hebrew
that ancient historians wrote. The study by Marko and his colleagues found
Still in its infancy, "this is a new field of research", he says,
"And because of a shortfall in the budget, progress is much slower than desired."
In addition to Marko and Allenblum, the team of geologists also includes Dr
Amots Agnon from the Hebrew University and Prof. Tom Rockwell
from the University of California at San Diego. The team mainly investigates the
The northern regions, Eilat and the Dead Sea. "They will never be able to predict which one
What day and at what time will the earthquake occur," says Marko, "but the research will help us know which areas are at increased risk, so they can build in these areas accordingly."
The scope of the destruction that will be caused by the next earthquakes can be learned from the remains of a Crusader citadel in Mesad Aterat, near the Bnot Ya'akov bridge in the north, which Marko and his colleagues are investigating. The citadel, which has survived two earthquakes so far, as far as is known, sits exactly on the Syrian-African fault.
On one side of the fault is a Sinai-Israel plate and on the other side a plate
evening. On normal days the fracture is "locked", it does not move. When the earthquakes occurred, a certain place in the fault split, the Sinai-Israel plate moved south and the Arabian plate moved north. The noise lifted the citadel wall from its place. The citadel's special location on the fault line provides researchers with a rare opportunity to accurately measure the movement of the wall and thus know what the noise intensity was. The greater the displacement of the plates, the greater the intensity of the noise.
The first earthquake in the citadel occurred in the early morning hours of May 20, 1202 and shook the entire Middle East. The echoes of the noise were felt from Iraq to Sicily. It toppled towers and walls in Acre, destroyed Tiberias and also Tire and Damascus were largely destroyed. In the measurements made by the researchers it was discovered that the displacement of the plates was 1.6 meters. "This means that this region is capable of producing stronger earthquakes than the one that has now killed tens of thousands in Turkey," says Marko.
"The intensity of the destruction is capable of damaging monumental buildings." The thickness of the walls of the citadel, which was built with impressive rigor, is four meters. In terms of earthquakes, today's construction is certainly no better than such construction, he adds.
The second earthquake, which occurred in 1759, was weaker, but it also caused great destruction. About 1,300 people were killed in Safed. The earthquake also devastated Acre, Haifa, Tiberias, Deir Hana, the Shoof area, Beirut and Tripoli. The Mufti of Damascus described how the great mosque in the city collapsed, the citadel of the city shook and many people were killed, detailing a long list of villages and textile houses that were destroyed during the earthquake.
"Earthquakes like this don't happen every day," Allenblum says. "It hasn't happened in 250 years, but this fact scares me more than if it had happened yesterday. It will be many more years before Izmit (in Turkey) or Cuba (in Japan) are destroyed once again, as they were in the recent earthquakes. They are actually relatively safe. A historical earthquake, which has not struck in recent years, indicates a greater danger in the near future to the specific place where it struck in the past, than one that happened a relatively short time ago."
The city of Eilat is also at high risk of being damaged by a devastating earthquake. In 1068, a very strong earthquake occurred in its area, which caused much damage in Aqaba and was also felt in Cairo. Uzi Avner from the Antiquities Authority discovered in the Almog Coast Reserve, which is located near the place where the oil pipeline passes today, the remains of an ancient settlement that sank into the sea, probably because of a series of strong earthquakes that hit the place. For the results of the earthquake at an underwater site in the Almog Coast Reserve, which is located near where the oil pipeline runs today. The last earthquake in the area was, as mentioned, four years ago, 100 kilometers south of Eilat. "The very fact that we see that activity has resumed again
in the Gulf of Eilat indicates that the region is once again under high stress," says Marko.
Another strong earthquake occurred in the Susita area, above the Sea of Galilee, on January 18, 749. The earthquake struck Katsrin, in the village of Nahumov in Beit Shan, in Tiberias, 30 houses were destroyed. The baths in Hamat Geder were also destroyed, and according to one source ten thousand people were killed by the noise. Archaeologists who excavated
In a crusader church in Susita, they found an apartment of huge stone pillars, all of which fell in one direction. "Susita teaches us what happens to a building on pillars," says Marko. "Also in Tiberias, Eilat and Beit Shan they build on pillars. These are places that are on the rift."
The oldest known earthquake occurred on September 2, 31 BC and hit the Masada area. The historian Josephus Flavius wrote that 30 thousand people were killed in it. "It may well be an exaggerated number," says Marko. But other historical sources indicate that it was a loud noise anyway. The earthquake hit Jerusalem, Bethlehem and Qumran, destroyed Herod's winter palace in Jericho and was felt even by the northern birds.
© Published in "Haaretz" on 05/09/1999
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