What Caused The Tohoku Earthquake

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TOHOKU, Japan, Friday, Mar. 11 -Yesterday, a 9.0 magnitude Earthquake struck the east of Tohoku, Japan. The epicentre of the earthquake was located approximately 72 km east of Tohoku (38.3 degrees North latitude and 142.4 degrees East longitude), or 130 km east of Sendai as shown by the X in figure 3 below. The focus of the earthquake was 24.4 km under the epicentre. The earthquake therefore caused a tsunami due to the displacing of water above the Pacific Plate. The earthquake and tsunami together have caused approximately 20,000 deaths, 6152 injuries and 2500 people missing. Approximately 90% of these deaths were by drowning. Approximately 140,000 people have been displaced and over 500,000 buildings and structures have been destroyed or …show more content…

This layer of clay is hypothesised to be the reason the two plates were allowed to slide the 50 metre horizontal distance and 10m vertical upthrust. This is the main scientific theory of how the earthquake and tsunami occurred.
However there were even more extreme circumstances on the line. The Fukushima Power Plants in Fukushima were severely damaged by the tsunami after the earthquake. Due to the 9.0 magnitude earthquake, a 15 metre tidal wave disabled the cooling system of three nuclear reactors and this caused a nuclear disaster which was rated 7 on the International Nuclear Events Scale. Nearby cities were endangered as the incident caused high radioactive releases that will last over 4 to 6 days. Approximately 100,000 people have been evacuated from their homes in order to protect them from the hazards of the radiation from the power plant. The power plants are being cooled to stabilise them as shown in Figure 7. Apart from cooling, the aim is to prevent the release of radioactive materials, especially the contaminated water that leaks from the three power plants. Government caution delayed the return of people home in order for residents to avoid radiation sickness. Attempting to maintain the evacuation itself however has caused 1000 deaths in comparison to the risk of radiation if people were allowed back to their …show more content…

An earthquake warning was given 1 minute before the earthquake for the Japanese people to have a chance to escape, though the warnings for the Haiti 2010 earthquake were ignored by officials, claims ‘The Australian’. Skyscrapers in cities of Japan are designed with shock absorbers and withstand earthquakes by swaying side to side when an earthquake occurs. The ratio of buildings destroyed to people killed infers that houses that were destroyed did not kill as many people, mainly due to the one minute warning that all Japanese citizens received to evacuate the buildings, but also because of the way Japanese houses are constructed; with regard to threat of earthquakes.
On a tectonic level, the Tohoku Earthquake was caused by subduction due to converging plates. On the other hand, Haiti 2010 was caused by the North American and Caribbean plates that move against each other in a left lateral strike slip motion. This indicates a transform plate boundary, rather than a convergent boundary, so large magnitude high damage earthquakes are common in this region.
The 2011 Tohoku Earthquake was the most powerful in Japan’s history as no other Japanese earthquake has reached the 9.0 magnitude on the Richter scale. The second highest magnitude ever recorded in Japan was an 8.9 on the Richter scale; however that was the Jogan Sanriku earthquake that took place in the year

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