What is an Earthquake?
An Earthquake isa sudden and violent shaking of the ground, that sometimes causes great destruction and loss of life, as a result of movements within the earths crust or by volcanic activity. Plate tectonics, which are large rocks that make up the earths crust. Plate tectonics are broken up in to many large pieces that can move. When plate tectonics slide past each other or collide together they cause earthquakes.
The TŌhoku Earthquake
The Tōhoku earthquake that hit Japan in 2011 was a very devastating and damaging earthquake. It destroyed so much of the Tōhoku region in Japan. It was not only a big earthquake that destroyed Tōhoku but because of the earthquake a tsunami occurred and several nuclear power plants had meldowns. The earthquake occurred on Friday the 11th of March 2011 at 5:46 (UTC). This earthquake was the most powerful earthquake to hit Japan and it was one of five of the most powerful earthquakes to ever hit (from modern record keeping since 1900).
How did it Happen?
The Tōhoku earthquake happened because of the plate tectonics underneath Japan. Plate tectonics are huge, unusual shaped slabs of solid rock created from either continental or oceanic crust. Crust is the thinest layer of the earth. Japan is on the Eurasian plate and next to the Eurasian plate is the Pacific plate. THese two plates move towards each other and collide together and the area where they meet is called a destructive margin. The Pacific plate is an oceanic plate tectonic therefore it is heavier than the Eurasian plate. As the plates are moving into each other the Pacific plate is sinking or sub-ducting under the Eurasian plate. The friction between the two plates cause the Pacific plate to stick to the Eurasian plate and while it stuck, the pressure between the two built up until the pressure was released and this action cause the earth under Japan to shake, causing the Tōhoku earthquake.
What did the earthquake cause?
In result of the earthquake massive tsunami's occurred and also destroyed much of Japan. The Tsunami's reached a height of 40.5 meters high and in some areas they went 10km inland. Also because of the tsunami's several nuclear power plants accidents. Because of these accidents many people in the area had to evacuate. The U.S.A. said that people who lived near the power plants had to be at least 80km away from it.
What were the effects of the earthquake?
The earthquake was so big and devastating that it caused a lot of harm to the people of Japan and also other countries. In result of the earthquake 129,225 buildings collapsed. Roads and railways were completely destroyed and a dam collapsed. 4.4 million households in northeastern Japan were left without electricity and 1.5 million were left without water. The Japanese National Police Agency reported that there were 5,692 deaths, 2,409 injuries, and 2,814 missing people. The earthquake was so big that it actually caused the main island of Japan, Honshu, to move 2,4 meters east and it caused the earth to move on its axis by almost 10cm.
More Facts about the earthquake
- The earthquake reached 9.0 on the Richter scale which is a scale that determines the size of and earthquake. 9.0 is extremely high on the Richter scale. (Look at the image below to see how high it is).
- The estimated insured losses from just the earthquake was between US$14.5 to US$34.6 billion. The bank of Japan offered the banking system US$183 billion so that they could normalize market conditions.
- There were quite a few of large foreshocks followed by hundreds of aftershocks. The foreshocks began on March 9th, 2011.
- The earthquake was an undersea megathrust earthquake meaning that the earthquake was actually an underwater earthquake and that is what cause the huge tsunamis.