抄録
Rupture process of the 2004 Sumatra-Andaman earthquake is estimated using tsunami waveforms observed at tide gauges and the coseismic vertical deformation observed along the coast. The average rupture speed of the 2004 Sumatra-Andaman earthquake is estimated to be 1.7 km/s from tsunami waveform analysis. The rupture extends about 1200 km toward north-northwest along the Andaman trough. The largest slip of 23 m is estimated on the plate interface off the northwest coast in the Aceh province in Sumatra. Another large slip of 21 m is also estimated on the plate interface beneath the north of Simeulue Island in Indonesia. The other large slip of 10-15 m is estimated on the plate interface near Little Andaman and Car Nicobar Inlands. The total seismic moment is calculated to be 7.2 × 1022 Nm (Mw 9.2) which is similar to the other studies using seismic waves (Park et al., 2005; Ammon et al., 2005).
