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A volcano avalanche in Sicily thousands of years ago caused a gigantic tsunami, which engulfed the Mediterranean Sea and ravaged the coastline of three continents in less than four hours, according to geological evidence and computer simulations.

In a study entitled "The Lost Tsunami," published in the current issue of the journal Geophysical Research Letters, Maria Teresa Pareschi and colleagues at Italy's National Institute of Geophysics and Volcanology suggest that the tsunami might also have caused the mysterious abandonment of a Neolithic village along the coast of present-day Israel.

Pareschi modeled the collapse of the eastern flanks of Mount Etna in the early Holocene (nearly 8,000 years ago), drawing a scenario in which six cubic miles of rock crashed into the water at a speed of 224 miles per hour.

According to the simulation, waves splashed tremendously high near the landslide area and traveled as far as the coasts of Southern Europe, North Africa and Asia Minor.

"It is hard to find on-shore evidence of such a catastrophic event because since then the sea level has increased by about 10 meters (33 feet). But we found a wealth of submarine evidence across the floor of the Ionian Sea and the Sirte Abyssal Plains in Africa," Pareschi told Discovery News.

Indeed, the simulation showed that pressure from the ancient tsunami liquefied thick layers of soft marine sediments across the Ionian seafloor and triggered a far-reaching underwater mudslide.

Holecene deposits in the Ionian Sea and the Gulf of Sirte in the form of so-called homogenite and megaturbidite deposits — both related to tsunami dynamics ­— would confirm the rapid and devastating event.

"Along the Calabrian coastline, the tsunami run-up wave reached heights of up to 40 meters (131 feet). The coasts of Greece and Libya were impacted by waves up to 13 meters (43 feet) high, while the coast of Egypt, Syria and Israel were inundated by two- to four-meter (six- to 13-foot) high waves," Pareschi said.

She believes that it is possible that the now submerged Neolithic village of Atlit-Yam in Israel was abandoned because of the Etna tsunami impact.

The village shows evidence of a sudden evacuation, including 6,000 fish that had been gutted and stored for future consumption and trade but then left to rot.

Europe's top expert on volcano-generated tsunamis, geophysicist Stefano Tinti of Bologna University, described the study as interesting and credible, adding that the ancient event holds lessons for present-day dangers.

"Although there is absolutely no immediate risk for collapses similar to the one described by Pareschi, we should not forget the danger of island volcanoes," Tinto told Discovery News. "It is important to have constant monitoring and a tsunami warning system in the entire Mediterranean area."

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