Chile, Haiti Quakes Explained

Significant aftershocks continue to rock Chile two days after a magnitude 8.8 earthquake brought down buildings and bridges, and triggered a tsunami. And yet it's already clear the devastation won't reach the levels seen in Haiti. Walter Mooney, a seismologist with the U.S. Geological Survey, explains the differences between the two quakes.

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MICHELE NORRIS, host:

Significant aftershocks continue to rock Chile two days after a magnitude 8.8 earthquake brought down buildings and bridges and triggered a tsunami. The death toll stands at more than 700. Some areas have yet to be reached. And yet, it's already clear that the devastation in Chile will not reach the levels that we saw in Haiti after the 7.0 earthquake there in January.

For an understanding of the differences between the two quakes, we've turned to Walter Mooney. He's a seismologist with the U.S. Geological Survey in Menlo Park, California. Thanks so much for being with us.

Dr. WALTER MOONEY (Seismologist, U.S. Geological Survey): It's my pleasure, Michele.

NORRIS: Many people right now point to the fact that the Haiti quake was smaller in magnitude. But when it comes to earthquakes, you're not just looking at magnitude, it seems like you're also looking at the frequency of shaking. Could you explain that concept to us, what shaking means?

Dr. MOONEY: Sure, Michele. Every earthquake of course causes some ground shaking. But, you know, the number of shakes per second is different for a very big earthquake. There you have relatively fewer shakes per second because it's a big earthquake like a cello. And you have an earthquake like Haiti, which I would compare to a violin with a higher pitch. And so the number of shakes per second is going to make a difference in how buildings and bridges and hospitals and schools respond.

Schools and hospitals are usually one story and two story, and they don't do very well with these high frequency shakes. In contrast, a tall building, like the 12 and 14-story apartment buildings in Chile, they don't do very well with these long period, few shakes-per-second kind of waves. So, with this frequent shaking near to the source, near to the epicenter, that kind of circumstance like in Haiti, people don't have a chance. They can't evacuate and the buildings come down very, very quickly. In contrast, in Chile, the earthquake would've started a little bit more with a rumble and people would have some chance to evacuate.

NORRIS: Does this have something to do with depth also?

Dr. MOONEY: Oh, boy. Depth off an earthquake is a really important parameter. And we can recall the earthquake that occurred only about a year ago in L'Aquila, Italy. Here, the earthquake was only a 6.3, but it ruptured right up to the surface with devastating results, the reason being that the city was sitting basically right on the fault. So, any structure that had not been designed with earthquake engineering in mind, it never had a chance and it came down right away.

NORRIS: It's very unsettling to see these back-to-back earthquakes. Where else in the world are seismologists predicting major quakes right now?

Dr. MOONEY: Boy, we have a lot of places that we're very, very concerned about. Tehran is one city in the Middle East where we have more than 10 million people living right on a fault. You know, the population pressure is so great for people to move to the capital cities and to occupy that area that's - it's an economic pressure. Other cities that we worry about a lot is Caracas, Venezuela, Quito, Ecuador, Lima, Peru and, well, you know, the list goes on.

Northern India is a highly populated area that hasn't seen a really big earthquake for about 100 years. And we worry about that region as well. So, I would have to say that, you know, we don't have a list of the top five. Unfortunately, our list of the top concerns would probably be 25 mega cities, all of which are in peril from the great earthquake.

NORRIS: Walter Mooney, thank you very much.

Dr. MOONEY: You're welcome.

NORRIS: Walter Mooney is a seismologist with the U.S. Geological Survey in Menlo Park, California.

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Chile Imposes Curfew Amid String Of Aftershocks

  • Chilean troops and firefighters unload relief supplies Wednesday from a military helicopter in the coastal town of Dichato, which was heavily damaged by tsunami waves produced by Saturday's 8.8-magnitude earthquake.
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    Chilean troops and firefighters unload relief supplies Wednesday from a military helicopter in the coastal town of Dichato, which was heavily damaged by tsunami waves produced by Saturday's 8.8-magnitude earthquake.
    Ricardo Mazalan/AP
  • A policeman stands near medicine and other items donated Wednesday for earthquake victims.
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    A policeman stands near medicine and other items donated Wednesday for earthquake victims.
    Evaristo Sa/AFP/Getty Images
  • A woman washes her hands at a makeshift shelter for displaced people in the seaside town of Constitucion on Tuesday.
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    A woman washes her hands at a makeshift shelter for displaced people in the seaside town of Constitucion on Tuesday.
    Fernando Vergara/AP
  • Secretary of State Hillary Clinton is greeted by Chilean President Michelle Bachelet at the airport in the capital, Santiago, on Tuesday.
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    Secretary of State Hillary Clinton is greeted by Chilean President Michelle Bachelet at the airport in the capital, Santiago, on Tuesday.
    Pablo Martinez Monsivais/AP
  • Chilean army armored personnel carriers drive along a bridge Tuesday in Concepcion, the country's second-largest city. Bachelet said Chile has dispatched 14,000 to devestated areas.
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    Chilean army armored personnel carriers drive along a bridge Tuesday in Concepcion, the country's second-largest city. Bachelet said Chile has dispatched 14,000 to devestated areas.
    Daniel Garcia/AFP/Getty Images
  • People wait for supplies in front of a supermarket in Concepcion.
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    People wait for supplies in front of a supermarket in Concepcion.
    Aliosha Marquez/AP
  • Police arrest a woman who was carrying goods out of a supermarket in Concepcion.
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    Police arrest a woman who was carrying goods out of a supermarket in Concepcion.
    Mario Quilodran/El Mercurio/AP
  • Rescue workers help an injured woman in Concepcion.
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    Rescue workers help an injured woman in Concepcion.
    Francesco Desgasperi/AFP/Getty Images
  • A man holds a child outside a quake-damaged building in Concepcion early on Saturday.
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    A man holds a child outside a quake-damaged building in Concepcion early on Saturday.
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  • A boat rests next to a building Monday after it was washed ashore by the tsunami in Talcahuano.
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    A boat rests next to a building Monday after it was washed ashore by the tsunami in Talcahuano.
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  • Throughout central Chile, travelers faced obstacles. Here, a collapsed bridge across the Claro river, about 112 miles south of Santiago.
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    Throughout central Chile, travelers faced obstacles. Here, a collapsed bridge across the Claro river, about 112 miles south of Santiago.
    Aliosha Marquez/AP
  • Smoke from a burning building fills the sky on the outskirts of Santiago.
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    Smoke from a burning building fills the sky on the outskirts of Santiago.
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  • Firemen search for survivors in a destroyed building in Concepcion on Sunday.
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    Firemen search for survivors in a destroyed building in Concepcion on Sunday.
    Natacha Pisarenko/AP
  • People in Concepcion stand outside guarding their homes on Monday.
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    People in Concepcion stand outside guarding their homes on Monday.
    Natacha Pisarenko/AP
  • A man holds a torn and soiled Chilean flag on Sunday in a flooded area of Pelluhue, about 200 miles southwest of Santiago.
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    A man holds a torn and soiled Chilean flag on Sunday in a flooded area of Pelluhue, about 200 miles southwest of Santiago.
    Roberto Candia/AP
  • Bejamira Neira Zapata sits in the doorway of her house Monday after the massive earthquake struck the village of Penco. The tsunami engulfed the normally placid Penco and neighboring villages.
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    Bejamira Neira Zapata sits in the doorway of her house Monday after the massive earthquake struck the village of Penco. The tsunami engulfed the normally placid Penco and neighboring villages.
    Evaristo Sa/AFP/Getty Images
  • Concepcion, about 70 miles from the epicenter, suffered some of the worst damage.
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    Concepcion, about 70 miles from the epicenter, suffered some of the worst damage.
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  • Following one of the largest earthquakes ever recorded, a woman stands in front of a destroyed home in Pelluhue.
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    Following one of the largest earthquakes ever recorded, a woman stands in front of a destroyed home in Pelluhue.
    Roberto Candia/AP

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Police fired tear gas at looters in the central Chilean city of Concepcion as the country's president and the United Nations vowed to speed delivery of food and water in the aftermath of an earthquake and tsunami that have killed more than 700 people.

Epicenter Of The Quake

Map Of The Epicenter Of The Quake

President Michelle Bachelet described the disaster as "an emergency without parallel in Chile's history." Chilean officials initially balked at international assistance, but Bachelet appealed for help as the scope of the devastation from Saturday's 8.8 magnitude quake became clearer.

In Concepcion, 230 miles south of the capital city of Santiago, rescuers searching for an estimated 60 people trapped inside a collapsed 15-story apartment building, heard victims knocking. They began drilling through thick concrete to reach them, fire Commander Juan Carlos Subercaseux said. By late Monday, firefighters had pulled 25 survivors and nine bodies. At one point, rescuers had to pause because of tear gas fired at looters grabbing everything from canned milk to microwave ovens at a damaged supermarket across the street.

The known death toll rose to 723, with 19 others missing, the National Emergency Office announced. Roads and bridges are devastated and an estimated 500,000 homes are badly damaged.

The United Nations on Monday said it would rush assistance, including temporary bridges, field hospitals, satellite phones, electric generators, damage assessment teams, water purification systems, field kitchens and dialysis centers.

"We are prepared to provide assistance," U.N. spokesperson Elisabeth Byrs told The Associated Press in Geneva. "It could be quite fast, given that our experts are on standby and were alerted in the region."

The World Health Organization said it expected the death toll to rise in the coming days as communications improve and the extent of casualties becomes clearer.

In Concepcion, the city nearest the epicenter, police used tear gas and imposed a curfew in an effort to control looting. Jaime Toha, the governor of Concepcion province, said 55 people were arrested overnight Sunday for violating curfew.

Survivors in the city reportedly were angered by the slow pace of getting government-issued relief supplies. Bachelet promised imminent deliveries of food, water and shelter for thousands living on the streets. She ordered troops to help deliver food, water and blankets and clear rubble from roads, and she urged power companies to restore service first to hospitals, health clinics and shelters. Field hospitals were planned for hard-hit Concepcion, Talca and Curico.

Bachelet, who leaves office March 11, also signed a decree giving the military control over security in the provinces of Concepcion and Maule and announced a 9 p.m.-6 a.m. curfew for all non-emergency workers.

Reporter Annie Murphy told NPR that she saw numbers of people out in the streets searching for food and water as she traveled into Concepcion. She also said people had mixed feelings about the military presence. "Some find it kind of shocking because they haven't seen the military in the streets since the Pinochet dictatorship," Murphy said. "Other people say that they're glad to see them because of the disorder that was starting to become commonplace."

Efforts to get an assessment of the full extent of damage were complicated by continuing aftershocks that have done more damage and forced thousands of people to set up makeshift tent camps rather than return to their homes.

A family rested on mattresses set out on a street in Santiago's Yungay neighborhood. i i

A family rested on mattresses set out on a street in Santiago's Yungay neighborhood on Sunday, a day after the 8.8-magnitude earthquake struck central Chile. Carlos Espinoza/AP hide caption

itoggle caption Carlos Espinoza/AP
A family rested on mattresses set out on a street in Santiago's Yungay neighborhood.

A family rested on mattresses set out on a street in Santiago's Yungay neighborhood on Sunday, a day after the 8.8-magnitude earthquake struck central Chile.

Carlos Espinoza/AP

"If you're inside your house, the furniture moves," said Monica Aviles, pulling a shawl around her shoulders as she sat next to a fire across the street from her apartment building. As if to punctuate her fear, an aftershock set off shuddering and groaning sounds for blocks around.

In Santiago, there were only "pockets of devastation" Time magazine reporter Eben Harrell told NPR.

Harrell said the destruction was largely confined to the historic districts, but that more modern buildings — engineered to survive earthquakes — had fared much better.

State television showed scenes of devastation in coastal towns and on Robinson Crusoe Island, where the tsunami reportedly drove almost 2 miles into the town of San Juan Bautista. Officials said at least five people were killed there and more were missing.

Defense Minister Francisco Vidal acknowledged the navy made a mistake by not immediately activating a tsunami warning after the quake hit before dawn Saturday. Port captains in several coastal towns did, saving what Vidal called hundreds of lives. Thirty minutes passed between the quake and a wave that inundated coastal towns.

In the town of Constitucion, 350 people were reported dead after the killer wave struck.

"The tsunami destroyed almost everything on the seafront, [and] the center of the town was completely destroyed," Constitucion Mayor Hugo Tilleria told state television. "This means lots of people still haven't been accounted for."

The U.S. ambassador to Chile said officials were having difficulty getting information from the most devastated region of Concepcion.

In an interview by telephone with CBS on Monday, Ambassador Paul Simons said, "We do not have any confirmed reports of Americans who have died." He added that while officials have been able to contact "a few" of the estimated 1,000 Americans in Chile, "information is still very, very scarce."

He said the Concepcion area has suffered "major devastation" but life was returning to normal in Santiago.

Michael Black, who works for the Christian relief group World Vision, said that damage to infrastructure was making it hard to get aid supplies into the worst-hit areas in and around the capital.

"Roads are heavily damaged, especially the highway that surrounds Santiago," Black said. He added that his organization has a warehouse in Bolivia, but that it would be a challenge getting supplies to communities it needs to reach."

Secretary of State Hillary Clinton planned to briefly visit Santiago on Tuesday as part of a five-nation Latin America trip. Speaking to reporters while traveling in Montevideo, Uruguay, she said she would be bringing communications equipment to Chile.

Clinton said the Chilean government had asked her to proceed with the visit so that she could "assess whatever else they might need and immediately begin the process of providing it."

From NPR staff and wire reports

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