When a large earthquake happens beneath an ocean floor, it can change the level of the floor suddenly, raising and lowering it substantially. This produces a large disturbance in the sea. The size and energy of disturbance depends on the magnitude of the earth quake. Most severe earthquakes occur near the subduction zone of the tectonic plates. A wave starts spreading out. The height of the wave might be only a few meters, but this wave is very different from the normal oceanic waves produced by the action of the wind on the surface.
Japan Tsunami 2011
Tsunami - Words | Help Me
Tsunami is a set of ocean waves caused by any large, abrupt disturbance on the sea- surface. If the disturbance is close to the coastline, local tsunamis can demolish coastal communities within minutes. A very large disturbance can cause local devastation and export tsunami destruction thousands of miles away. Tsunamis rank high on the scale of natural disasters.
The Causes For Tsunami
The Indian Ocean earthquake was an undersea mega thrust earthquake that occurred at UTC on Sunday, December 26, , with an epicentre off the west coast of Sumatra, Indonesia. The quake itself is known by the scientific community as the Sumatra-Andaman earthquake. The earthquake was caused by subduction and triggered a series of devastating tsunamis along the coasts of most landmasses bordering the Indian Ocean, killing over , people in fourteen countries, and inundating coastal communities with waves up to 30 meters feet high. Indonesia was the hardest hit, followed by Sri Lanka, India, and Thailand.
Although the magnitude 9. Both Japan and Indonesia are volcanic lands in the Ring of Fire, which partly surrounds the Pacific Ocean in a giant series of subduction zones and volcanoes. Shortly after Japan stopped shaking at pm local time on Friday, March 11, we began hearing about troubles at a series of nuclear plants. After the reactors automatically shut down during the quake, emergency systems for removing heat still being generated in the reactors were routinely switched on. But because the electric grid was down and the standby generators were damaged — perhaps by seawater — the emergency cooling failed.