Earthquakes, plate tectonics and the Indian Ocean tsunami

The Indian Ocean tsunami originated from a 9.15 - 9.3 magnitude earthquake in Sumatra that released pressure which had built up over hundreds of years along the fault between 2 tectonic plates;\ud \ud In the 10 minutes after the fault break started off northwest Sumatra, the rupture spread north along a 1,300 km length of the fault line to the Andaman and Nicobar Islands;\ud \ud The tsunami generated many waves because the earthquake caused a sudden vertical displacement of a vast section of the ocean floor, displacing a huge mass of seawater;\ud \ud Tsunamis passing through the deep ocean are difficult to detect, can exceed speeds of 600 km/hour, and arrive at coasts thousands of kilometres from the earthquake as high energy, long wavelength waves;\ud \ud The waves slow as they encounter the continental shelf, bays, islands or estuaries and increase in height; thereby causing massive damage when they reach the shoreline;\ud \ud The Indian Ocean tsunami was not the first of this type in the region and more will occur in the future; and\ud \ud Natural hazard risk analyses should be undertaken and an early warning system implemented to better prepare vulnerable coastal communities for environmental threats in the future