Indian Ocean Tsunami.ppt

Indian Ocean Tsunami  -2004 By Ji Zeliang The 2004 Indian Ocean earthquake occurred at 00:58:53 UTC on 26 December with the epicenter off the west coast of Sumatra, Indonesia. The shock had a moment magnitude of 9.1–9.3. The undersea megathrust earthquake was caused when the Indian Plate was subducted by the Burma Plate and triggered a series of devastating tsunamis along the coasts of most landmasses bordering the Indian Ocean, killing 230,000 people in 14 countries, and inundating coastal communities with waves up to 30 meters high. The sudden vertical rise of the seabed by several meters during the earthquake displaced massive volumes of water, resulting in a tsunami that struck the coasts of the Indian Ocean. A tsunami that causes damage far away from its source is sometimes called a teletsunami and is much more likely to be produced by vertical motion of the seabed than by horizontal motion. The tsunami, like all others, behaved very differently in deep water than in shallow water. In deep ocean water, tsunami waves form only a small hump, barely noticeable and harmless, which generally travels at a very high speed of 500 to 1,000 km/h ; in shallow water near coastlines, a tsunami slows down to only tens of kilometers per hour but, in doing so, forms large destructive waves. THANKS! 2016/3/23 *