Tsunami Generation from the
2004 M=9.0 Sumatra Earthquake

Tsunami Generation Modeling

Using techniques described by Geist and Dmowska (1999) and Geist (2002), the slip distribution determined from the inversion of seismic waveforms can be used to calculate the vertical displacement of the sea floor caused by the earthquake. This, consequently, starts the tsunami. Propagation of tsunami waves outward from the source can be modeled using standard techniques, based on the shallow-water wave equations (Satake, 2002). Below are snap shots of the simulation of the local tsunami, with links to animations.
 

Tsunami wave field in the Bay of Bengal. View to the north west, focused near the earthquake epicenter (northern Sumatra).
(see a larger version of this image, 117 kb)
See the animation (17 MB)

Tsunami wave field in the Bay of Bengal after 66 minutes. View to the north west.
See the animation (7.5 MB).

Tsunami wavefield after tsunami generation looking to the south east.
See the animation (6 MB).

Other tsunami propagation models use a much longer rupture that is consistent with the aftershock distribution (yellow circles in map above). Much of the ongoing research is focused on determing details of the earthquake source for this important event.

References

Contents:
  Tectonics of Sumatra-Andaman Islands (81 kb)
  Seismological Aspects of Tsunami Generation (70 kb)
  Tsunami Generation Modeling (58 kb)
  References