HR: 0800h
AN: U51A-0015    [Abstracts]
TI: Modeling Ruptures and Tsunamis That May Follow Event of September 12
AU: * Babeyko, A Y
EM: babeyko@gfz-potsdam.de
AF: GeoForschingsZentrum-Potsdam, Telegrafenberg, Potsdam, 14473, Germany
AU: Sobolev, S V
EM: stephan@gfz-potsdam.de
AF: GeoForschingsZentrum-Potsdam, Telegrafenberg, Potsdam, 14473, Germany
AU: Harig, S
EM: Sven.Harig@awi.de
AF: Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven, 27570, Germany
AU: Androsov, A
EM: Alexey.Androsov@awi.de
AF: Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven, 27570, Germany
AB: The seismic series of the 12-13 September near the Padang/Bengkulu region in Western Sumatra, Indonesia, emerged to, but did not rupture the three locked patches at the subduction plate interface as recently derived from geodetic and paleogeodetic studies (Chlieh et al., 2007), likely increasing probability of the next giant earthquake off Padang. Future earthquake, when rupturing all of the three locked patches, may reach a magnitude of about M=9 and repeat giant historical event of 1797 and partly that of 1833 followed by severe tsunamis. We have modeled possible earthquake and tsunami scenarios assuming future ruptures coinciding with each of the presently locked patches. Our modeling is performed in a framework of the currently developed German- Indonesian Tsunami Early Warning System (GITEWS). Resulting tsunami wave height in Padang is very sensitive to the location of the ruptured patch. The shallow patch under the Siberut island and the deep patch just off Padang, both result in M=8.4 earthquakes. However, the latter rupture would result in considerably shorter arrival time and in more than 5 times higher run-up in Padang. We show that GPS stations at islands and at Padang can be used to estimate rupture parameters and to predict tsunami heights just after the earthquake. Our modeling also demonstrates that historical records about the 1797 tsunami are more consistent with the simultaneous rupturing of both the shallow and deep patches off Padang.
DE: 1207 Transient deformation (6924, 7230, 7240)
DE: 1217 Time variable gravity (7223, 7230)
DE: 4255 Numerical modeling (0545, 0560)
DE: 6924 Interferometry (1207, 1209, 1242)
SC: Union [U]
MN: 2007 Fall Meeting