Japanese Earthquake Essay

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On the 11th of March 2011 at 14.46 a great 8.9 magnitude earthquake struck Japan’s north eastern coast triggering off a 33 foot tsunami that swept away anything in its path including houses, cars and boats. Many people mistake tsunamis for tidal waves which they most definitely are not, tidal waves are caused by the moon, sun, and planets upon the tides as well as the wind as it move over the water contributing to push it to the shore. No, a tsunami is a large ocean wave usually caused by an underwater earthquake or a volcanic explosion. There are about 20 plates along the surface of the earth that move continuously and slowly past each other. When the plates squeeze or stretch, huge rocks form at their edges and the rocks shift with great force, causing an earthquake. Think of it this way: Imagine holding a pencil horizontally. If you were to apply a force to both ends of the pencil by pushing down on them, you would see the pencil bend. After enough force was applied, the pencil would break in the middle, releasing the stress you have put on it. The Earth's crust acts in the same way. As the plates move they put forces on themselves and each other. When the force is large enough, the crust is forced to break. When the break occurs, the stress is released as energy which moves through the Earth in the form of waves, which we feel and call an earthquake. However they are also similar to Seismic Waves, which are where energy created by an earthquake travels in waves from the epicentre, where they are the strongest. The waves shake buildings, structures and the earth vertically, causing them to move horizontally. The plate boundaries that caused the earthquake were the Pacific and North America plates, and were generated in a subduction zone. An oceanic plate was being forced down into the mantle by plate tectonic forces and the friction between the sub ducting plate
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