This earthquake killed about 23,000 people, injured 76,000, and caused just over 1 billion dollars in property damage. The earthquake also caused a number of landslides. Tsunamis, or tidal waves, form when an earthquake causes a sudden movement of the seafloor. This movement creates a wave in the water body which radiates outward in concentric shells. On the open, ocean these waves are usually no higher than one to three meters in height and travel at speed of about 750 kilometers per hour.
Tsunamis become dangerous when they approach land.
Frictional interaction of the waves with the ocean floor, as they near shore, causes the waves to slow down and collide into each other. This amalgamation of waves then produces a super wave that can be as tall as 65 meters in height. This photo shows a beached fishing boat that was carried landward by the tsunami wave.