A Japanese researcher suggests that the tsunamis caused by Monday's powerful earthquake off Indonesia's Sumatra Island topped 5 meters in some areas.
Associate Professor Shunichi Koshimura of Tohoku University's Disaster Control Research Center made the calculation based on data gathered during the quake.
Koshimura says the tsunami spread outward from the epicenter and that the position of the fault caused the waves to grow larger on the northeastern side, where the hardest-hit Mentawai Islands lie.
His analysis indicates that waves of 3 to 4 meters hit South Pagai Island within 20 minutes.
A simulation also showed that the waves topped 5 meters at the southern end of the island, reaching up to 5.2 meters in some places.
Koshimura says the tsunami was especially high in that part of the island because of its protruding landscape.
He says the shapes of the coastlines and seabed characteristics at such places can cause waves to converge and amplify.