The tsunami was a terrible natural where this disaster in its history has claimed many lives.
Tsunami is a Japanese language which means ocean waves, that is the big wave coming from the sea towards the mainland as masiv. This situation makes an area where the tsunami suffered enormous damage. http://www.whatcausesearthquakes.com
Generally causes a tsunami is an earthquake whose center is located below sea level.
Tsunamis can occur if an interruption occurs that causes the displacement of large amounts of water, such as volcanic eruptions, earthquakes, landslides or meteorite that fell to earth. However, 90% a tsunami is due to undersea earthquakes. In recording the history of some of the tsunami caused by the volcanic eruption, for example, when the eruption of Mount Krakatoa.
Vertical movement in the Earth’s crust, can lead to the seafloor rise or drop suddenly, resulting in disruption of water balance that was on it. This resulted in the energy flow of sea water, which when it reached the coast into big waves resulting tsunami.
Tsunami wave speed depends on the depth of the sea where the waves occur, where speed can reach hundreds of kilometers per hour. When the tsunami reaches the shore, the speed will be approximately 50 km / h and energy is very damaging coastal path.
Mid-ocean tsunami wave height is only a few centimeters to a few meters, but when it reaches shore wave height can reach tens of meters due to the accumulation of past water. When it reaches the coast of the mainland tsunami will creep away from the shoreline with a range of several hundred meters even several kilometers.
This vertical movement can occur on earth fault or faults. The earthquake also occurred in subduction zones, where oceanic plate under the continental plate infiltrates into.
Landslides on the ocean floor and volcanic debris can also cause interference with sea water to generate a tsunami. The quake that caused the movement perpendicular to the layer of earth. As a result, the sea floor heaving suddenly so that the balance of seawater on it undisturbed. Similarly, cosmic or meteor that fell from above. If the size of the meteor or landslide is big enough, it can happen megatsunami which reaches hundreds of meters.
The earthquake that caused the tsunami
* Earthquake centered in the sea and shallow (0-30 km)
* An earthquake with a strength of at least 6.5 on the Richter Scale
* An earthquake with a pattern of reverse fault or the fault down