April 6, 2009 L'Aquila, Italy Earthquake

Updated 4/7/2009

A 6.3 Magnitude earthquake hit L'Aquila, Italy, 55 miles north of Rome, at 01:32 GMT on April 6, 2009, 3:32 AM, local time, causing major damage and hundreds of deaths. Several aftershocks caused additional damage, including a 5.5 M quake on the 7th.

207 people have been confirmed dead, 1500 injured and over 17,000 homeless. L'Aquila is a city of 70,000. The original walled city was built in the 13th century. Although many older buildings collapsed, modern buildings were not spared. A hospital built as recently as 2000 partially collapsed, forcing patients out into the open and making it harder to treat them. Italy has building standards for earthquake resistant buildings but it is not always observed. Most of the casualties were caused by collapsed buildings as people slept. Heavy rains since the quake has hampered rescue efforts.

Survivors whose homes have been destroyed or are feared to be unsafe are sleeping in their cars, in hotels, or in tent cities that have been set up for the refugees. People have been digging in the rubble with their bare hands, as well as with heavier equipment. Some of the earliest stories were of people digging students out of a collapsed dormitory. Prime Minister Silvio Berlusconi pledged help in rebuilding the city.

Tectonically, Italy is in the center of a number of forces any one of which can cause quakes. Italy is involved in a collision to the north with Europe that is raising the Alps. At the same time a mini-plate to the east, the Adria (under the Adriatic Sea) is subducting beneath Italy, while the Tyrrhenian basin to the west (under the Tyrrhean Sea between the Italian mainland and the islands of Corsica and Sardinia) is expanding. This quake, in the middle of Italy in the Apennine mountains is related mostly Tyrrhean expansion. This area has been the site of major earthquakes in the past. In 1997 a series of earthquakes killed 11 people and caused significant damage. In 1703 a large earthquake destroyed much of the city.

(See the Plate Tectonics page for more information on these processes.) The US Geological Survey (USGS) is an invaluable resource in understanding and tracking earthquakes. See the USGS summary of this quake.

See also the following news stories:

* Strong Quake in Italy kills over 150, wounds 1500 (AP 4/6/09)
* Aftershocks hit Italy quake zone (BBC 4/7/09)
* Italy Earthquake deaths soar(BBC 4/7/09)
* Quake buildings 'below standard'(BBC 4/7/09)
* Did a Seismologist Accurately Forecast the L'Aquila Earthquake--Or Was It a Lucky Guess?(Scientific American 4/7/09)

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