| Caption: |
(a) Fault displacement lifts the water above mean sea level, which creates potential energy that drives the horizontal propagation of the waves. In these diagrams, wave height is greatly exaggerated compared to the depth of the water. Actual height of the waves is at most a meter or so, but it is spread out to tens or several hundreds of kilometers in length. (b) The initial wave is split into a tsunami that travels out across the deep ocean (distant tsunami) and another tsunami that travels toward nearby land (local tsunami). The wave heights are also split and each (distant and local) tsunami has a height about one-half the original wave in (a). (Modified after U.S. Geological Survey; http://walrus.wr.usgs.gov/tsunami/basics.html) |
