Nov 29, 2014
A tsunami is a series of very long ocean waves created when a large body of water is displaced. There are many places in Japan that have been hit by a Tsunami and they are mainly caused by earthquakes. The government has many of obstacles to face after a tsunami hits. This is why its important for the government to be prepared when a disaster like this happens. Tsunamis can take everything away from you so quickly if you don’t try to do anything to prevent it. Causes of Tsunamis
Japan is placed along the world's most active earthquake belt, the Pacific Ring of Fire, where rigid plates in the Earth's crust collide along the rim of the Pacific Ocean. There are plenty of things that can cause a tsunami. The majority of earthquakes in Japan are caused by large earthquakes on the bottom of the sea when slabs of rock move past one another, immediately causing overlying water to move. (Commonwealth of
Australia, 2014) This results waves to move away from the source of the event.
(Commonwealth of Australia, 2014) The fault where the earthquake occurred must be underneath or near the ocean and cause vertical movement of the sea floor (several meters) over a large area (hundred thousands square kilometers). (International
Tsunami Information Center, 2014) Shallow focus earthquakes (less than 70 meters) along subduction zone are responsible for most destructive tsunamis. (International Tsunami Information Center, 2014) Landslides can also cause a tsunami. When rock falls, ice falls, or submarine fall under water, its
causes and huge displacement of water which causes the tsunami.(Neamtic, 2014)
Along with landslides, a volcanos can cause a tsunami. This can happen by a volcanic slope failure by a volcanic explosion, by a volcanic and phreatomagmatic explosion and a collapsed engulfments of volcanic magmatic chambers. (Neamtic, 2014) This would usually happen in Pacific Ocean around the ring of fire. (Neamtic, 2014) Lastly the rarest cause of a tsunami is an extraterrestrial collision. When asteroids and meteors hit the ocean causing a large displacement of water.(Neamtic, 2014) Scientists have calculated that if a 56 kilometer asteroid hit the middle of the Atlantic Ocean the tsunami will travel up to the Appalachian Mountains in the upper ⅔ of the United States.on both sides. (Neamtic, 2014) Tsunami waves can travel up to 800 kilometers.(International Tsunami Information
Center, 2014) They can move from one side to the Pacific Ocean to the other in a day and move across the Indian Ocean 12 hours. (International Tsunami Information
Center, 2014) These destructive waves can get up to 10 feet tall.(International Tsunami
Information Center, 2014) Wave length is a factor that distinguishes tsunamis from wind waves. (Neamtic, 2014) They can be more than 200 kilometers long. As long as sea depth decreases wave height increase. (Neamtic, 2014) Everyone should be informed about what causes a tsunami.
Historical Disasters in Japan
On March 11, 2011 in Tohoku Japan an earthquake struck along a subduction zone where two of the earth’s plate tectonics collided. (Oskin,2014) On the east of Japan, the
Pacific plate dove beneath the overriding Eurasian plate.(Oskin,2014) The trembler released centuries of built up stress. (Oskin,2014) This happened only 45 miles away and 25 miles at depth. (Oskin,2014) This was rated a major tsunami because the waves were more than 6 meters high. (Oskin,2014) The waves overtopped and destroyed protective tsunami seawalls at several locations.
(Oskin,2014) Tokyo had a 5 minute warning this was some time to prevent some deaths.(Oskin,2014) Only 58% of Fukushima and Miyagi headed for higher ground.
(Oskin,2014) The waves reached 128 feet high in Miyako city. (Oskin,2014) Water hit 6 kilometers inland Sendai and flooded 217 square