NEWS

Crucial fault line runs up the spine of earthquake-prone Italy

Gregg Zoroya
USA TODAY

The earthquake that devastated villages in central Italy Wednesday was triggered along a fault line that has tormented the Italian peninsula for centuries, making the country among the most quake-prone regions of Europe.

A view of collapsed and damaged houses and cars after the earthquake in Pescara del Tronto, central Italy, on August 24, 2016, following a 6.2 magnitude earthquake, according to the United States Geological Survey, that struck at around 3:30 am local time.

The magnitude-6.2 quake, which left at least 120 people dead, occurred squarely within a band of "high seismic hazard" running along the axis of the north-south Apennines mountain range, according to the U.S. Geological Survey.

The centuries-old architecture in the region places it at even higher risk of damage and deaths. "Many of the towns feature stone construction, including a deep history of architecture dating back to Roman and in some cases Etruscan times," the survey said in a statement.

The event fell between two relatively recent earthquakes along the same fault line.

In 2009, a magnitude-6.3 earthquake leveled the village of L'Aquila, killing 295, injuring 1,000 and leaving 55,000 homeless. The village is 20 miles southeast of Wednesday's destruction.

In 1997, a magnitude-6.0 quake occurred 30 miles northwest of there, leaving 11 dead and destroying 80,000 homes in the Marche and Umbria regions.

At least 247 dead as quake rocks central Italy

"There's a lot of geological things going on in that particular part of Europe," said Robert Sanders, a  geophysicist with the survey.

He said the area marks a collision between the Africa and Eurasia tectonic plates, with a fault line that crosses Sicily before running along the spine of the Italian boot.

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While the geological conditions make Italy and Greece most at risk for earthquakes in Europe, those countries pale in comparison to other quake-stricken regions, particularly the Pacific Rim where the Philippines, Indonesia, Japan and Chile are at high risk of very strong quakes, Sanders said.

Apart from the size of an earthquake, a multitude of factors prove why one can to be more damaging and lethal than another.

"Building structure has a lot to do with damage," Sanders said. "For example, Chile has very high, very strict building codes because they're so earthquake-prone, and they get some of the largest earthquakes in the world. So (for) a magnitude-6.2 earthquake in Chile, we wouldn't expect to see damage on this scale that we're seeing in Italy."

Many of the ancient homes of Italy are without protective retrofitting, he said, and the quake occurred before dawn, when most residents were asleep in their bedrooms.

"That's why we're seeing a lot of these devastating pictures and videos coming in from some of these towns where entire blocks and buildings are just in rubble," he said.