Tsunami!. What happened & why. 2004 Indian Ocean Earthquake . Undersea earthquake Magnitude 9.0 ( Moment magnitude scale ). NOAA. Epicenter 150 KM west of Sumatra. http://en.wikipedia.org/wiki/2004_Indian_Ocean_earthquake.
What happened & why
Occurred along the subduction zone where the Indian dives under the Eurasian Plate
A tsunami (pronounced soo-NAA-mee) is a series of waves (called a "wave train") generated in a body of water by a pulsating or abrupt disturbance that vertically displaces the water column.
Tsunami's are also mistakenly referred to as tidal waves as they often resemble a tide that keeps rising, rather than cresting waves when they reach shore. However, as they are not actually related to tides the term may be misleading, and its use is discouraged by scientists.
Anthony Liekens 15:30, 28 Dec 2004 (UTC)
Many countries around the Pacific, including Hawaii, have warning systems and evacuation procedures in the event of a serious tsunami.