1960 valdivia earthquake, chile
The 1960 Valdivia earthquake or Great Chilean Earthquake of 22 May 1960 was the most powerful earthquake ever recorded, rating 9.5 on the moment magnitude scale. It occurred in the afternoon (3:11 pm local time), and the resulting tsunami affected southern Chile, Hawaii, Japan, the Philippines, eastern New Zealand, southeast Australia, and the Aleutian Islands in Alaska. The epicenter was near Lumaco , approximately 570 kilometres south of Santiago, with Temuco being the closest large city. Valdivia was the most affected city. The tremor caused localised tsunamis that severely battered the Chilean coast, with waves up to 25 metres. The main tsunami raced across the Pacific Ocean and devastated Hilo, Hawaii. Waves as high as 10.7 metres were recorded 10,000 kilometres from the epicenter, and as far away as Japan and the Philippines.
This image shows the main areas affected by the initial tremor. We can see that Chile is right on the outskirts of the orange or "Severe" zone of the earthquake.
Chile is on the western coast of the continent of South America; this is the boundary between two tectonic plates, the Nazca plate (oceanic plate) and the South American plate (continental plate). In this region the Nazca plate is moving eastwards towards the South American plate. The dense oceanic crust of the Nazca plate is being forced under or subducted beneath the less dense continental crust of the South American Plate. The Nazca and South American plates are converging at a rate of approximately 80mm / year. This causes stress to accumulate resulting in elastic strain which stores energy. Once the stress exceeds the strength of the rocks in the crust a brittle failure occurs, causing in this case thrust faulting to occur. The stored elastic strain energy is released in the form of seismic waves.
Social Impacts
The earthquake that struck Valdivia destroyed farms, killing numerous livestock and people. Barns and industrial structures were destroyed by the quake. The dairy industry was among the few industries of the affected zone that received subsidies and investment after the earthquake. It received state support through a long-term policy after the earthquake. Regarding deaths, there is not really a certain amount that has been confirmed, but most researchers say that it is around 1500-1700. This is still considerably fewer than some estimates which were as high as 5,700. However, others stated that the initial reports were greatly overestimated. The death toll for this huge earthquake was less than it might have been because it it occurred in the middle of the afternoon, many of the structures had been built to be earthquake-resistant and the series of strong foreshocks had made the population wary. What makes this earthquake so renowned is this damage that it caused to Chile AND to other countries. A concurrent tsunami caused by the earthquake caused 61 deaths, $75 million damage in Hawaii; 138 deaths and $50 million damage in Japan; 32 dead and missing in the Philippines; and $500,000 damage to the west coast of the United States.
Economic Impacts
In 1959, the Chilean economy had a great recession with per capita GDP decreasing by 8%, which recovered in 1960 with a per capita GDP growth of 6%. However, after the earthquake the country's economy grew at a lower rate of 2% in 1961 to 1963, and had a second recession in 1964-65. The exact cost of the disaster remains unknown but is estimated at approximately $550 million in losses. In repairing the damage, the Chilean state invested 136.4 million U.S. dollars from abroad in the form of donations and 292.6 million from the government.
Environmental Impacts
It has been estimated that about 40% of the houses in Valdivia were destroyed, leaving 20,000 people homeless. The most affected structures were those built of concrete, which in some cases collapsed completely due to lack of earthquake engineering. Traditional wooden houses fared better; although in many places, they were uninhabitable, they did not collapse. Houses built upon elevated areas suffered considerably less damage compared to those on the lowlands, which absorbed great amounts of energy. Many city blocks with destroyed buildings in the city center remained empty until the 1990s and 2000s, with some of them still used as parking lots. In terms of urban development, Valdivia suffered the loss of the minor but significant Cau-Cau bridge, a bridge that has not been rebuilt. The other bridges suffered only minor damage. Land subsidence in Corral Bay improved navigability as shoal banks, produced earlier by sediments from Madre de Dios and other nearby gold mines, sank and were compacted. As the earthquake destroyed Valdivia's flood barriers, general land subsidence exposed new areas to flooding. The earthquake created several landslides which were so great that they changed the course of some rivers.
In what ways do LEDCs suffer from earthquakes?
Compared to MEDCs, LEDCs are obviously not as wealthy so they do not have as many emergency services available to the general public. Communication systems may be underdeveloped, so the population may not be well educated about what to do in the event of a volcanic eruption or an earthquake. Construction standards tend to be poor in LEDCs. Homes and other buildings may suffer serious damage when a disaster occurs. Buildings collapsing can cause high death tolls. Evacuation and other emergency plans can be difficult to put into action due to limited funds and resources. Clearing up can be difficult. There may not be enough money to rebuild homes quickly and safely. Many people could be forced to living in emergency housing or refugee camps.
Social Impacts
The earthquake that struck Valdivia destroyed farms, killing numerous livestock and people. Barns and industrial structures were destroyed by the quake. The dairy industry was among the few industries of the affected zone that received subsidies and investment after the earthquake. It received state support through a long-term policy after the earthquake. Regarding deaths, there is not really a certain amount that has been confirmed, but most researchers say that it is around 1500-1700. This is still considerably fewer than some estimates which were as high as 5,700. However, others stated that the initial reports were greatly overestimated. The death toll for this huge earthquake was less than it might have been because it it occurred in the middle of the afternoon, many of the structures had been built to be earthquake-resistant and the series of strong foreshocks had made the population wary. What makes this earthquake so renowned is this damage that it caused to Chile AND to other countries. A concurrent tsunami caused by the earthquake caused 61 deaths, $75 million damage in Hawaii; 138 deaths and $50 million damage in Japan; 32 dead and missing in the Philippines; and $500,000 damage to the west coast of the United States.
Economic Impacts
In 1959, the Chilean economy had a great recession with per capita GDP decreasing by 8%, which recovered in 1960 with a per capita GDP growth of 6%. However, after the earthquake the country's economy grew at a lower rate of 2% in 1961 to 1963, and had a second recession in 1964-65. The exact cost of the disaster remains unknown but is estimated at approximately $550 million in losses. In repairing the damage, the Chilean state invested 136.4 million U.S. dollars from abroad in the form of donations and 292.6 million from the government.
Environmental Impacts
It has been estimated that about 40% of the houses in Valdivia were destroyed, leaving 20,000 people homeless. The most affected structures were those built of concrete, which in some cases collapsed completely due to lack of earthquake engineering. Traditional wooden houses fared better; although in many places, they were uninhabitable, they did not collapse. Houses built upon elevated areas suffered considerably less damage compared to those on the lowlands, which absorbed great amounts of energy. Many city blocks with destroyed buildings in the city center remained empty until the 1990s and 2000s, with some of them still used as parking lots. In terms of urban development, Valdivia suffered the loss of the minor but significant Cau-Cau bridge, a bridge that has not been rebuilt. The other bridges suffered only minor damage. Land subsidence in Corral Bay improved navigability as shoal banks, produced earlier by sediments from Madre de Dios and other nearby gold mines, sank and were compacted. As the earthquake destroyed Valdivia's flood barriers, general land subsidence exposed new areas to flooding. The earthquake created several landslides which were so great that they changed the course of some rivers.
In what ways do LEDCs suffer from earthquakes?
Compared to MEDCs, LEDCs are obviously not as wealthy so they do not have as many emergency services available to the general public. Communication systems may be underdeveloped, so the population may not be well educated about what to do in the event of a volcanic eruption or an earthquake. Construction standards tend to be poor in LEDCs. Homes and other buildings may suffer serious damage when a disaster occurs. Buildings collapsing can cause high death tolls. Evacuation and other emergency plans can be difficult to put into action due to limited funds and resources. Clearing up can be difficult. There may not be enough money to rebuild homes quickly and safely. Many people could be forced to living in emergency housing or refugee camps.