JERUSALEM (AP)—With Israel situated in one of the world’s earthquake-prone areas, officials are taking action to protect the Holy Land’s most important ancient treasures so they don’t come tumbling down.
After a series of five moderate earthquakes shook the country in October, experts installed a seismic monitoring system at the Tower of David, one of Jerusalem’s most important—and most visible—historical sites.
The project is Israel’s first attempt to use such technology to determine structural weaknesses in the countless ancient edifices that dot the Holy Land. The efforts, however, have been slowed by authorities’ reticence to publically declare sites as vulnerable, as well as the explosive geopolitics surrounding ancient Jewish, Christian and Muslim sites at the heart of the Mideast conflict.
“We have to remember that this is the Holy Land,” said Avi Shapira, head of a national steering committee for earthquake preparedness. “We have some responsibility not only to preserve the historical monuments of our personal heritage … but also for the rest of the world.”
Most of Israel’s historical sites “have not been checked,” said Shapira. “We have them on the map, but an engineer still hasn’t visited them.”
Israel sits along the friction point of the African and Arabian tectonic plates, and is prone to small tremors. The earthquakes in October caused no major damage, but made Israelis jittery. About once a century throughout history, a large earthquake has rattled the region, often damaging key historical sites. The last major quake occurred in 1927.
The Al-Aqsa Mosque, Islam’s third holiest site, was destroyed in an earthquake shortly after it was built in the 8th century and was damaged and repaired multiple times since due to quakes. The 1927 quake, which was over 6 in magnitude, caused hundreds of deaths and damaged Al-Aqsa and the Church of the Holy Sepulcher, built on the site where Jesus is believed to have been crucified and buried.
Israel has been bracing for another major earthquake for years. But those efforts have focused on retrofitting existing schools and hospitals and apartment buildings, and improving standards in new construction.
The country is just getting around to surveying its historical sites, and the assessment process has turned out to be sensitive.
Government experts have not published any findings on historical sites at risk, and it is unclear which government authority would be compelled to take responsibility for sites should they face earthquake damage.
In the past, Israeli involvement in the Old City’s ancient buildings has sparked protest from Palestinians who seek sovereignty there in their quest for an independent state.
The only site in the Old City that Israeli officials say is being checked for a possible earthquake risk is the Tower of David, one of Jerusalem’s most ubiquitous symbols. The minaret-topped stone tower stands in the corner of an ancient citadel fortress, and six major cracks in the tower have the staff worried if it can withstand an earthquake.
“This is the symbol of the city, the symbol of Jerusalem, for more than 2000 years. So that’s why this is a real nightmare for us,” said Eilat Lieber, director of the Tower of David museum.
Researchers from the University of Padua in Italy installed sensors throughout the tower to determine what kind of earthquake-proofing it might need.
Accelerometers along the tower measure small movements caused by wind and traffic, in order to predict how an earthquake would impact the structure. At the very top of the minaret, thin bars affixed to the stones slide like bicycle tire pumps to measure the movement of cracks. Data collected by the equipment will be analyzed to determine any structural flaws in the tower and if needed, to suggest engineering solutions to stabilize the site.
Initial assessments for the Tower of David are good. Claudio Modena, a University of Padova engineer, said the tower seems to be capable of withstanding an earthquake because its ancient foundations sit on bedrock. Three steel rings that hug the cracked minaret, installed during earlier British rule in the city, have helped save it from collapse, he said.
Orna Cohen, chief conservator of the Tower of David, said that in the event of an earthquake, Jerusalem’s most ancient structures of massive stones might actually be the city’s most dependable.
“If they still stand after so many earthquakes during the last 2000 years, they must be good structures,” Cohen said.
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