Special Issue: Flare-Substorm/Space Weather Topics
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Waveform inversion for slip distribution of the 2006 Java tsunami earthquake by using 2.5D finite-difference Green’s function
Earth, Planets and Space volume 61, pages e17–e20 (2009)
We first incorporate the large effect of near-source heterogeneity on teleseismic body waveforms in the inversion of the slip distribution of the 2006 Java tsunami earthquake. We incorporate the effect by computing the response of an assumed “2.5D” model structure of the Java trench by a 2.5D finite-difference method. Based on a simulation of inversion, we suggest that intense smearing is possible when we apply 1D Green’s functions in the analysis, and that it may obscure the slip pattern. In the inversion of real data, we confirm macroscopic features, such as a long duration (∼ 165 s) and a slow rupture velocity (∼ 1.25 km/s). The region of the initial rupture is found to be isolated from the eastern broad region in which we further identify a heterogeneous slip distribution. Most of these regions are likely to be at the sedimentary plate interface where the accreted sediment and the subducting plate are in contact. In particular, the nearly “isolated” feature of a shallow slip region suggests a possible faulting in the shallowest part of the sedimentary plate interface without being strongly enforced by the rupture propagated from the deeper part of the fault. Such heterogeneity suggests a highly variable frictional behavior at the sedimentary plate interface.
Ammon, C. J., H. Kanamori, T. Lay, and A. A. Velaso, The 17 July 2006 Java tsunami earthquake, Geophys. Res. Lett., 33, L24308, doi:10. 1029/2006GL028005, 2006.
Bilek, S. L. and E. R. Engdahl, Rupture characterization and aftershock relocations for the 1994 and 2006 tsunami earthquakes in the Java subduction zone, Geophys. Res. Lett., 34, L20311, doi:10. 1029/2007GL031357, 2007.
Bilek, S. L. and T. Lay, Tsunami earthquakes possibly widespread manifestations of frictional conditional stability, Geophys. Res. Lett., 29, doi: 10.1029/2002GL015215, 2002.
Dziewonski, A. M. and D. L. Anderson, Preliminary reference Earth model, Phys. Earth Planet. Inter., 25, 297–356, 1981.
Fujii, Y. and K. Satake, Source of the July 2006 West Java tsunami estimated from tide gauge records, Geophys. Res. Lett., 33, L24317, doi:10. 1029/2006GL028049, 2006.
Hara, T., Magnitude determination using duration of high frequency energy radiation and displacement amplitude: application to tsunami earthquakes, Earth Planets Space, 59, 561–565, 2007.
Hyndmann, R. D., M. Yamano, and D. A. Oleskevich, The seismogenic zone of subduction thrust faults, The Island Arc, 6, 244–260, 1997.
Kanamori, H., Mechanism of tsunami earthquakes, Phys. Earth Planet. Inter., 6, 346–359, 1972.
Kanamori, H. and J. W. Given, Use of long-period surface waves for rapid determination of earthquake-source parameters, Phys. Earth Planet. Inter., 27, 8–31, 1981.
Kato, T., T. Ito, H. Z. Abidin, and Agustan, Preliminary report on crustal deformation surveys and tsunami measurements caused by the July 17, 2006 South off Java Island Earthquake and Tsunami, Indonesia, Earth Planets Space, 59, 1055–1059, 2007.
Kennett, B. L. N. and E. R. Engdahl, Traveltimes for global earthquake location and phase identification, Geophys. J. Int., 105, 429–465, 1991.
Kopp, H., D. Klaeschen, E. R. Flueh, and J. Bialas, Crustal structure of the Java margin from seismic wide-angle and multichannel reflection data, J. Geophys. Res., 107, doi:10.1029/2000JB000095, 2002.
Laske, G., G. Masters, and C. Reif, CRUST 2.0: A new global crustal model at 2×2 degrees, http://mahi.ucsd.edu/Gabi/rem.html, 2001.
Pelayo, A. M. and D. A. Wiens, Tsunami earthquakes: slow thrust-faulting events in the accretionary wedge, J. Geophys. Res., 97, 15321–15337, 1992.
Polet, J. and H. Kanamori, Shallow subduction zone earthquakes and their tsunamigenic potential, Geophys. J. Int., 142, 684–702, 2002.
Okamoto, T., Teleseismic synthetics obtained from three-dimensional calculations in two-dimensional media, Geophys. J. Int., 118, 613–622, 1994.
Okamoto, T. and H. Takenaka, Effect of near-source trench structure on teleseismic body waveforms: an application of a 2.5D FDM to the Java trench, in Advances in Geosciences, Solid Earth Volume, edited by Kenji Satake, 308 pp (approx.), World Scientific Publishing Company, Singapore, 2009 (in press).
Seno, T., Tsunami earthquakes as transient phenomena, Geophys. Res. Lett., 29, doi:10.1029/2002GL014868, 2002.
Takenaka, H. and B. L. N. Kennett, A 2.5-D time-domain elastodynamic equation for plane-wave incidence, Geophys. J. Int., 125, F5–F9, 1996.
Tanioka, Y. and T. Seno, Sediment effect on tsunami generation of the 1896 Sanriku tsunami earthquake, Geophys. Res. Lett., 28, 3389–3392, 2001.
Tanioka, Y., L. Ruff, and K. Satake, What controls the lateral variation of large earthquake occurrence along the Japan Trench?, The Island Arc, 6, 261–266, 1997.
Tsuji, Y., S. Han, Fachrizal, I. Gunawan, and T. Kato, Distribution of runup heights of the tsunami of the South off Central Java Earthquake of July, 17, 2006, Programme and Abstracts, Seism. Soc. Japan, 2006, Fall Meeting, C002, 2006.
Wessel, P. and W. H. F. Smith, Free software helps map and display data, EOS Trans. AGU, 72, 441, 1991.
Wiens, D. A., Bathymetric effects on body waveforms from shallow subduction zone earthquakes and application to seismic processes in the Kurile Trench, J. Geophys. Res., 94, 2955–2972, 1989.
Yamanaka, Y. and M. Kikuchi, Asperity map along the subduction zone in northeastern Japan inferred from regional seismic data, J. Geophys. Res., 109, B07307, doi:10.1029/2003JB002683, 2004.
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Okamoto, T., Takenaka, H. Waveform inversion for slip distribution of the 2006 Java tsunami earthquake by using 2.5D finite-difference Green’s function. Earth Planet Sp 61, e17–e20 (2009). https://doi.org/10.1186/BF03352919
- Rupture process
- tsunami earthquake
- finite-difference method
- teleseismic waveform inversion