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Tsunami models courtesy Jose Borrero, Tsunami Research Center, University of Southern California

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This is the entire region scenario, which is caused by 20 meters of slip on the entire Mentawai patch (nearly 800 km long), with slip extending from just east of the islands all the way up to the trench. First, you see the initial deformation of the sea surface related to the rupture of the megathrust -- about 6 meters of uplift southwest of the islands, about 2 to 4 meters under the islands, and subsidence of about a meter at Padang (on the coast at about 1 degree south) and 2 meters at Bengkulu (on the coast at about 3.8 degrees south). As the movie runs, you see the orange bulge propagate both southwestward and northeastward. In this view, you can't see much detail of the tsunami at any particular spot. Download movie
Detail of what happens at Padang (population about 800,000, between about 0.9 and 1.0 degrees south) on the mainland coast. The sea retreats until about 25 minutes after the earthquake. Then within the next ten minutes, the first crest arrives. It reaches a height of about 5 meters. The next wave crest arrives at about 55 minutes and is also about 5 meters high. Download movie
Prognostications for Bengkulu (about 350,000 people, around 3.8 degrees south). Before the movie starts you see the coseismic deformation pattern -- a 3-meter trough in the sea surface is just offshore. As the movie runs you see that there is very little withdrawal of the sea after the earthquake, but that the trough arrives at the tip of the peninsula at 3.8 degrees about 13 minutes after the start of the earthquake. The sea begins to rise there about 19 minutes after the start of the earthquake. By thirty minutes, it has risen to about 7 meters and that level is sustained for about 10 minutes. By one hour, another trough has arrived. Surprisingly, at about 2 hours, another big wave arrives. It travels down the coast and reaches heights of about 7 meters, also. Notice the characteristics of the tsunami north of the peninsula, in the two large river drainages at about 3.75, 3.77 and 3.79 degrees. The inundation distances (the distance the waters flow overland) are enormous -- several kilometers. Download movie
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