6/23/2001 Peru Earthquake

Updated 7/2/2001

On the afternoon of June 23, 2001 at 20:33 GMT (15:33 local time) a 8.1 magnitude earthquake struck southern Peru. The epicenter was 110 miles (180 km) SSE of Puquio, Peru,120 miles (190 km) W of Arequipa, Peru , 200 miles (325 km) SSW of Cuzco, Peru and, 375 miles (600 km) SE of LIMA, Peru. 102 people have been confirmed dead with 1,368 injuries and 46,470 estimated homeless according to Peru's Civil Defense Institute. The biggest city in the area is Arequipa, Peru's second largest. Other cities that were hard hit include Moquegua and Tacna. Portions of Bolivia and Chile also were affected with relief efforts also ongoing there. Communications following the quake have been hampered by damaged roads, mudslides and downed electric and phone lines.

Arequipa is known for beautiful colonial architecture. Many of these buildings have been severely damaged, including the cathedral, which was originally built in 1656. One of its steeples fell and the other was severely damaged. Traffic has been restricted in the central section of the city because of fears that the vibrations could cause further collapse.

Witnesses said that the ground made huge waves during the quake, which lasted over 1 minute. A tsunami caused by the quake drowned 39 people in a coastal village but tsunami warnings for the Pacific were withdrawn with no damage elsewhere.

Earthquakes over 8 Magnitude are known as "Great" Earthquakes and are capable of largescale devastation. This quake would have been much more damaging in a more heavily populated area.

The Earthquake occurred in the Nazca Tectonic Plate just off the coast. The Naca Plate and the South American Plate are moving towards eachother. At this point the Nazca Plate is just starting to descend under the South American Plate. This quake was considered shallow, only being about 20 mi (33 km) deep. As the Nazca Plate moves east it descends deeper and deeper until it hits the earth's mantle, where the heat and pressure are enough to melt and absorb it. Magma rises from this point to fuel the Andes' volcanoes. As you move east from the coast, earthquakes originate deeper and deeper in the descending plate. (See the Plate Tectonics page for more information on these processes.)

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2/28/2001 Nisqually, Washington Earthquake

Updated 3/2/2001

The quake occurred at 18:55 GMT (10:55 AM Pacific Standard Time). The magnitude was 6.8. The epicenter was between Tacoma and Olympia, Washington, about 10 miles northeast of Olympia. The focus of the quake was 30 miles deep. It was felt strongly in Portland and Vancouver, British Columbia. There were also reports that it was felt in San Francisco and Salt Lake City.

320 people were injured, 4 seriously. Damage estimates are over $2 billion. There have been considerably reports of damage, especially in Olympia near the epicenter of the quake. There have been many buildings there suffering structural damage. There is a large crack in the dome of the State Capitol Building and serious damage to other state office buildings. The legislature is right in the middle of its 105 day session. Both the Governor, the legislature and the state Supreme Court have had to relocate due to serious damage to their buildings. The Governor's Mansion is uninhabitable. Governor Locke's 2 year old son just missed being hit by a television that fell over in the Governor's Mansion. Some streets and sidewalks were badly buckled. There were also cracks in the ground up to several inches wide. Seattle skyscrapers swayed violently but apparently not dangerously. Lots of windows were broken and many buildings in downtown Seattle suffered a lot of damage, especially in the historic Pioneer Square district. In many places bricks fell from building facades. Some parked cars were covered with debris. Harborview Medical Center in Seattle closed one wing and evacuated patients. About 30 people were stranded for a couple of hours in the Space Needle while the elevators were checked. Some buildings were evacuated and Sea-Tac airport was closed for 4 or 5 hours. There was considerable damage to the Control Tower, with many of the windows broken. The Air Traffic controllers were temporarily relocated to vans next to the runway. The Portland airport was also closed. Seattle Ferry traffic was disrupted while the Seattle dock was evaluated. Passengers were stranded for a few hours on ferries that happened to be on the water at the time. Some highway bridges, including the Alaskan Way Viaduct, an elevated freeway along Seattle's waterfront were closed while crews checked for damage. Landslides closed some highways in the Cascades as well as Highway 101 north of Olympia. 100,000 people lost power but most of it was restored by the end of the day. Most of the damage was in the Olympia and Seattle areas, although there was isolated damage further away. The Peninsula College Little Theater in Port Angeles was closed due to damage and one historic office building in downtown Port Townsend had several cracks in its facade. A middle school gym in Port Townsend may also have suffered structural damage.

School children throughout the area followed instructions from their earthquake drills and ducked under their desks when their teachers told them, "We are having an earthquake. Duck under your desks and stay quiet so we can hear." Most schools were undamaged and the school day continued. Some parents did pick up their children early though.

Immediately after the quake there were large crowds of people milling around in the streets of Seattle, Olympia and as far away as Portland. Many people were alarmed by the buildings swaying in the quake and ran out into the street. In general, downtown streets are the least safe place to be during and immediately after an earthquake. The most common damage is broken windows and collapse of building facades. Both of these will shower the streets below with debris. Even when buildings do collapse they often fall into the streets. (In the Indian earthquake in January 350 schoolchildren were buried under a collapsed building facade as they marched down the street in a parade.) If there had been aftershocks to this quake, it could have brought down more debris onto the crowds below. The congestion may also have interfered a bit with emergency response. Many people were sent home early leading to considerable traffic congestion throughout the day.

This quake was similar to the quakes in Seattle in 1939 and on 4/13/1949 and 4/29/1965. The 1949 7.1 quake released 3 times as much energy as this quake. The relatively deep focus of the earthquake tended to lessen the damage since it put the focus further from the surface. The relatively deep focus also spread out the effects over a large area. The quake was caused by tensional faulting in the Juan de Fuca plate, which is subducting under the North American Plate in this area. The plate is under strain as it is bent while going under the North American Plate.

The Seattle fault is a shallower fault in the North American Plate that is also thought to be a danger for an earthquake that could cause considerably more damage. The prospects for an earthquake on the Seattle fault are not thought to be affected by this quake. The prospects for a major subduction quake off the Pacific Coast are probably not affected either. A major subduction quake could have a magnitude of 8-9 causing major damage over a large area as well as a possible tsunami. (See the Plate Tectonics page for more information on these processes.)

This quake was rated as moderate. There are several quakes this large every year throughout the world. Damage from a quake of this size depends largely on how near it is to population centers and the types of buildings in the area. In an area with unreinforced masonry buildings and no building codes, a quake like this could cause hundreds, even thousands of casualties. In a relatively unpopulated area, it could cause very little damage. This quake was in a major urban area, so it affected a lot of people, but an area that was aware of earthquake risks and has had building codes in place that require quake safe building methods. Many, but not all, older buildings have been retrofitted to improve their resistance to earthquakes. This quake can also be contrasted to the 1994 Northridge earthquake, which had a 6.7 magnitude, similar to this one, but with a shallower 11 mile deep focus, That quake caused a lot more damage and killed 72 people.

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2/13/2001 El Salvador Earthquake

Updated 2/20/2001

At 7:22 AM local time (1422 GMT) 2/13/01 an earthquake measuring 6.6 Magnitude with an epicenter 15 miles from San Salvador. The death toll is over 283 with a combined total of 1,200 dead from both recent earthquakes. Another 100,000 people were made homeless from this quake. One million people are now homeless. Damage from this quake tended to be in areas that suffered less damage in the larger January earthquake. Aftershocks from both quakes have people in a state of panic. There have been landslides and collapsed buildings. Clouds of dust billowed up from the volcano outside of San Salvador but there was no volcanic activity associated with the quake. Power and telephone service were interrupted for a while and the airport was briefly closed to check for damage. Landslides have cut off whole communities. Helicopters and heavy machinery was used to clear the debris.

Relief services in El Salvador are already stretched and thousands are still homeless from the last quake. This will make their job more difficult but President Flores called on people to pull together once more to meet the emergency. UN agencies providing relief are coming under strain from the two quakes in El Salvador and the huge Indian quake, all of which occurred in a span of a few weeks. International aid is slowing down and authorities are worried about "donor fatigue" from this string of disasters. Although this quake was smaller than either the Indian quake or January's quake, it still ranks as a major disaster in its own right. El Salvador's economy has been crippled and a large proportion of the population is unable to provide for their own needs. It will be a long time before the jobs and housing can be restored. There are concerns about sanitation and the water supply as well as the spread of disease. El Salvador was still recovering from Hurricane Mitch 3 years ago when the quakes struck.

Geologically, this quake is not considered an aftershock of January's because its epicenter was different. January's quake was a deep focus quake located in the Cocos Plate as it is subducted or pulled under the Caribbean Plate. The February quake had a shallow focus in the Caribbean Plate. The quakes may be related since they both represent the interaction of the same two plates. Similar sequences of quakes have been studied elsewhere in recent years. However, these quakes are totally unrelated to the recent earthquake in India, which involved completely different plates almost halfway around the world. (See the Plate Tectonics page for more information on these processes.)

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1/26/2001 India Earthquake

Updated 2/4/2001

An earthquake measuring 7.9 Magnitude hit the city of Bhuj, a desert town of 150,000 people in Gujarat state near the Pakistani border in western India at 0316 GMT (8:46 AM local time) 01/26/01.

Over 15,000 people are confirmed dead with 55,000 injured. The death toll could go as high as 30,000 to 35,000 according to relief agencies. The official estimate puts damage at over $4.5 Billion. Descriptions of the area nearest the epicenter are of total devastation. Over 100 buildings collapsed. Medical facilities were overwhelmed by the casualties, with hospitals themselves suffering devastating damage. People are being warned to avoid going back into their houses for fear of further damage from aftershocks, which have been numerous. Some aftershocks have been has strong as 5.9 Magnitude. Nine days after the main quake, aftershocks are still powerful enough that they threaten the collapse of still more buildings and send panicked people rushing out into the streets. Authorities are worried that many buildings are in dangerous condition and have banned people from entering them. Highrises are leaning and could collapse at any time. As is usually true after a quake of this magnitude, there are aftershocks several times a day that tend to keep people on edge, even when they don't cause more damage.

The quake was felt as far away as Nepal, 1,000 miles to the north and Bangladesh, 1,200 miles to the east. Buildings swayed in New Dehli (600 miles, 966 Km away), where Republic Day(India's Independence Day) celebrations were just about to get underway. In Gujarat 350 children participating in a parade were buried as buildings collapsed on them. Most of the casualties were in Gujarat state, although there were some in other parts of India and in Pakistan. The quake was the most powerful to strike India since Aug. 15, 1950, when an 8.5 magnitude temblor killed 1,538 people in northeastern Assam state.

Electric, Gas, Telephone and Water services were knocked out throughout Gujarat. After a few days service was restored in the major cities but outages continue in the hardest hit areas. Authorities said that the 2 nuclear power plants in Gujarat were not damaged. Thousands of the dead were from Bhuj, where 90% of the buildings sustained damage and more than half the buildings have been destroyed. AP reports 1/26/01 "In Ahmedabad, a center of India's textile industry, as many as 50 multistory buildings crumbled. Hundreds of people besieged the fire station asking for help to dig out their relatives, said fire chief Rajesh Bhat" Rescue efforts used both heavy cranes and people digging by hand in a desparate attempt to save loved ones. Nine days after the quake there are very few people being found alive. Thousands are leaving the area on foot due to a lack of food, water and shelter. There have been allegations of shoddy building practices being responsible for some of the damaged buildings. the government promises to investigate this.

The Indian Government is sending 10,000 tents and shipments of grain to the region. International aid has been offered from many countries, including Pakistan, and the United Nations is sending an evaluation team. The government is treating the emergency on a war footing, asking people to rally around to help. The military is taking a leading role in getting supplies to the quake area and treating the wounded. Two naval hospital ships are being used to treat injured people. The Air Force is flying in 40 flights a day with food and medical supplies. Two days after the quake authorities are worried about the spread of disease due to inadequate sanitary facilities and thousands of unburied bodies, although the World Health Organization (WHO) states that there are no diseases transmitted by dead bodies. There is a lack of firewood for cremations but more is being brought into the area. Many small funeral pyres burn throughout the area. Contaminated water is being blamed for an increase in diarrhea but there have not been any major outbreaks of disease. There is still danger of the spread of cholera or malaria due to poor living conditions for survivors. Respiratory illness is common due to people having to live outside in cold weather. Many villages did not receive help until a week after the quake. Efforts have so far been concentrated in the cities but the Prime Minister has now called for more help for the countryside as well. The government has come in for strong criticism in the hardest hit areas for not asking for international aid sooner and for not getting help to outlying areas for days after the quake. Desperate people have clashed with police over distribution of food.

This quake was caused by the movement of the Indian Plate as it moves northward into the Eurasian Plate. The quake had a shallow focus as the earth's crust adjusted to the strain caused by this collision. Gujarat is located on the Western edge of the Indian Plate near the intersection of the Eurasian Plate and the Arabian Plate. Although the collision of the Indian Plate and the Eurasian Plate has created the Himalayas, this quake was cause by the plates in the area slipping past each other. (See the Plate Tectonics page for more information on these processes.)

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1/13/2001 El Salvador Earthquake

Updated 2/20/2001

At 11:34 AM local time (1734 GMT) 1/13/01 an earthquake measuring 7.6 Magnitude with an epicenter in the Pacific Ocean 65 miles 110 km) off the coast of El Salvador. The nearest town was San Miguel. Unlike the 1986 7.5 M quake that devastated the capital, San Salvador, this quake caused extensive damage mostly in the countryside. The quake was felt across El Salvador, Guatemala, Nicaragua and Honduras and as far north as Mexico City. As is common after a large quake, there have been frequent aftershocks, some of them up to 5.7 Magnitude. People are sleeping in the streets for fear of further damage to their houses. President Flores is urging calm, dismissing rumors that aftershocks could cause tsunamis or volcanic eruptions. He said that although the danger is not past there are not likely to be anything as strong as the original quake. There have been additional building collapses and landslides triggered by aftershocks.

Over 1,000 people are confirmed dead, 2500 injured and 750,000 homeless. 141,000 houses were destroyed. The homeless are living in refugee camps with no where to go. President Flores ordered 3,000 coffins from Columbia immediately following the quake. 500 of the fatalities were people trapped in a landslide in San Tecla outside of San Salvador. A hillside collapsed, covering up to 500 houses. Rescuers hurried to uncover the houses in the hope of finding survivors. The BBC reports that residents claim that construction of the houses had been done improperly, undermining the hillside. Early efforts were hampered by lack of equipment. Roads have been blocked by landslides, communications are difficult and power is out throughout the country. The airport was closed for a day or two after the quake due to heavy damage to the passenger terminal. Many buildings have collapsed, including a church over 100 years old. 50,000 people have been evacuated from dangerous areas due to fears of further landslides. According to the BBC 1/16/01 "As many as half of the country's six million people are without water supplies, the Pan-American Health Organization said. Efforts are being intensified to get food, blankets and tents to those made homeless. Improvised shelters of canvas and plastic have been erected and the army is distributing rations of rice and beans."

President Flores has declared a national disaster and called for international aid. Total damage from the quake is estimated at $1.3 billion, over 15% of the annual economic output.. Mexico was the first to send a rescue team, followed by Taiwan, Switzerland and many other countries, including the USA. Taiwan sent a rescue team formed after their 1999 disastrous quake. Relief supplies include helicopters, dogs trained to find buried victims, food, blankets and money. After about a week the focus changed from rescue to relief . Bodies were being buried as quickly as possible in mass graves to prevent the spread of disease. There is an urgent need to care for those displaced by the quake. There has been some speculation that deforestation due to extensive logging destabilized hillsides and increased the severity of the landslides.

CNN reports, "A 22-year-old man was rescued after he alerted searchers by tapping for hours on concrete debris that had fallen on him. Another trapped man escaped death by using a cellular phone to call for help and inform rescuers of his location."

Geologically the quake was caused by the subduction of the Cocos Plate under the Caribbean Plate. The Cocos Plate is one of the remnants of a larger plate to the east of the Pacific Plate. The Juan De Fuca Plate, off of the Pacific Northwest coast of the United States and British Columbia, Canada, is another remnant of that plate. These plates are subducting under the neighboring plates to the east and will eventually be entirely consumed, as it was off the California coast where the Pacific Plate is now directly against the North American Plate in the San Andreas fault zone. (See the Plate Tectonics page for more information on these processes.)

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