Shaky Masada
SHAKY MASADA: SHORING UP THE FOUNDATIONS OF HISTORY, by Hanson R. Hosein, NBC
News
(Masada -- ISRAEL) "Masada must not fall again!" goes the rallying cry of an epic poem from the 1920's. It was a line that helped inspire countless Jews to build the nation of Israel. And it's also part of the mythology that has made this desert stronghold built by King Herod overlooking the Dead Sea, such a popular tourist draw.
But Masada could conceivably fall again -- this time not to the Romans who
besieged the fortress and nearly a thousand Jewish militants two thousand years ago -- but literally, to the forces of nature. In its awe-inspiring location on the edge of the Judean Desert, it is situated on one of this planet's most volatile fault-lines: the Dead Sea Rift Valley. And although there hasn't been a serious earthquake near Masada in recent history, a few people here are concerned that a national treasure could be in danger.
"The Rift Valley is an active fault that does generate its own tremors every now and then," said Dr. Yossef Hatzor from the Rock Mechanics Laboratory at Ben-Gurion University. "Blocks have been sliding out since Herod built his palace until the present. It happens all the time."
Hatzor was the first person to detect Masada's instability. Two years ago, the National Parks Authority decided to install a new cable car to accomodate the huge number of tourists who were being forced to line up and wait to make the three hundred metre ascent to the mountain. Hatzor was asked to research the soundness of the "Snake Path" cliff where the cable car station and an adjoining bridge were to be built.
Almost immediately, he saw that several large blocks of rock were ready to slide. But the only way he could determine whether it was an unsafe situation was to sample the rock. Because of the size of the dolomite rock, this was impossible. Instead, Hatzor applied "block theory" to determine whether the block was at risk -- essentially he built a model and subjected it to the kind of stresses the real Masada might experience during an earthquake.
"It turns out that a very low magnitude earthquake would make this block unsafe, and the block would slide," Hatzor said.
Upon his recommendation, the cliff was stabilized through a delicate operation of injecting steel rods and bolts into the stone along the Snake Path, thereby preventing any of the rock from sliding into the bridge and endangering tourists.
Fortification of the Snake Path cliff cost about a half million dollars. Fortunately, the money was easily obtainable as Masada was undergoing a $40 million renovation of its tourist facilities at the time. But now, the money is all spent, and Hatzor's research has revealed another, potentially more serious problem.: Herod's palace is in danger.
A HISTORY LESSON
Herod the Great built his lavish fortress a hundred kilometers away from Jerusalem, partly as a retreat, but more as a place of refuge for himself. He availed himself of the natural defenses of the desert mountaintop with its excellent sightlines and limited access -- should his new Jewish subjects rise up against him or the Egyptian Queen Cleopatra invade Palestine. These origins by themselves render Masada a priceless archeological site. Remnants of Herod's palaces, his storehouses and bathouse still remain, along with beautiful mosaic
floors.
However, it was what happened at Masada seventy years after Herod's death that has made it the tourist attraction it is today. The Jewish Revolt against the Roman occupation was well underway. As the story goes, a last brave group of Jewish rebels fled Jerusalem to Masada, and withstood a two-year long siege by a 15,000-strong Roman Army. The crafty Romans finally built a ramp up the mountain slope. On their last night in Masada before the Romans broke through, the 967 rebels opted for mass suicide rather than surrender.
This is the stuff that nation-building legends are made of, and helps account for the 750,000 tourists Masada received last year. It must be noted that recent revisionists, including Israeli sociologist Nachman Ben Yehuda in his 1996 book, "The Masada Myth -- Collective Memory and Mythmaking in Israel," argue that the rebels were in fact Jewish extremists who had killed other Jews, who had been expelled from Jerusalem by their own people, and who had raided the Jewish towns around Masada before the siege.
TOO HIGH A PRICE?
Despite the historical controversy, Masada is seen as a showcase of Jewish heritage that should be preserved at all costs. But it seems that the Israeli government may have run out of money just as Dr. Hatzor also discovered that the mountain face supporting Herod's northern palace is also on shaky ground.
"We realized that the whole perimeter of the mountain could fall off," said Eitan Campbell, the deputy manager of Masada National Park. "We know what we have to do, now we're stuck with no money."
After the success of the Snake Path Cliff research, Hatzor and his team conducted a sophisticated computer simulation using DDA -- discontinuous deformation analysis -- developed at the University of California at Berkeley. He had noticed the imposing mass of discontinuous blocks of rock and cracked boulders that support the northern palace. To see how it would stand up to an earthquake, Hatzor recreated the volatile rock face on his computer and generated an earthquake (similar to the one that had occurred in 1995 in the Northern Sinai desert that had registered 7.1 on the Richter scale).
The results are shocking. The simulation shows the ground shifting and the
large shards of rock falling away. Hatzor admits it's an extreme event that may not happen in our lifetime. Still, it is clear that the ground beneath the northern palace needs shoring up.
"It will not be destroyed," he said. "Distinct blocks will slide out of the mountain slowly. But there are segments of the mountain cliff that are in our best interests to maintain for future generations, and we should try to slow down that process."
It won't come cheap. Masada's Campbell says they will need at least a million dollars to strengthen the north face of Masada, and that they have been unable to secure enough donations to even begin the work. If they can't raise the money, it will be Nature that will determine the final outcome of the storied cliffs of Israel's legendary Masada.
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