Major earthquake hits Chile

NY Times:

A massive 8.8-magnitude earthquake struck Chile early Saturday, shaking the capital of Santiago for 90 seconds and sending tsunami warnings from Chile to Ecuador.

Chile's TVN cable news channel was reporting 78 deaths, with the toll expected to rise.

The quake downed buildings and houses in Santiago and knocked out a major bridge connecting the northern and southern sections of the country.

It struck at 3:34 a.m. local time and was centered about 200 miles southwest of Santiago, at a depth of 22 miles, the U.S. Geological Survey reported. The epicenter was some 70 miles from Concepcion, Chile’s second-largest city, where more than 200,000 people live.

Phone lines were down in Concepcion as of 7:30 a.m. and no reports were coming out of that area. The quake in Chile was 1,000 times more powerful than the magnitude 7.0 earthquake that caused widespread damage in Haiti on Jan 12, killing at least 230,000, earthquake experts reported on CNN International.

The U.S. Geological Survey and eyewitnesses reported more than a dozen aftershocks, including two measuring magnitude 6.2 and 6.9.

“We have had a huge earthquake,” said Michelle Bachelet, Chile’s president, speaking from an emergency response center in an appeal for Chileans to remain calm. “We’re doing everything we can with all the resources we have.”

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Eyewitnesses on Facebook and Twitter reported that the quake was felt from Japan to Argentina. The quake struck at the end of the Chilean summer vacation, with hundreds of thousands of people expected to be traveling back home this weekend.

The Pacific Tsunami Warning Center issued a warning for Chile and Peru, and a less-urgent tsunami watch for Ecuador, Colombia, Panama, Costa Rica and Antarctica. It said a tsunami could also hit Hawaii later in the day, the Associated Press reported.

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The after shocks of this quake are nearly as large as the quake that hit Haiti. It will probably take several hours to get a handle on the damage done by this quake and the tidal waves it will cause are probably still pushing their way across the Pacific. Those near beaches need to be on the look out for the water suddenly receding before the wall of water comes ashore.

The BBC has a good description of the firces causing the quake:

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Because the quake occurred below the sea floor, tsunamis were also generated, and alerts were issued not just for the Chilean coast but across the Pacific in general.

The Nazca and South American tectonic plates are vast slabs of the Earth's surface and grind past each other at a rate of about 80mm per year.

The Nazca plate, which makes up the Pacific Ocean floor in this region, is being pulled down and under the South American coast.

It makes the region one of the most seismically active on the globe.

Since 1973, there have been 13 events of magnitude 7.0 or greater.

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It will be interesting to see if Chile's elevation is higher than it was before the quake.