- Open Access
Joint inversion of strong motion and geodetic data for the source process of the 2003 Tokachi-oki, Hokkaido, earthquake
Earth, Planets and Space volume 56, pages329–334(2004)
- The Erratum to this article has been published in Earth, Planets and Space 2004 56:Art12
The strong motion and geodetic data were individually inverted for the source process of the 2003 Tokachi-oki, Hokkaido, earthquake with a hypocenter 25 km deep and a fault plane above the subducting Pacific slab. Both the results show a simple slip distribution with a single major asperity, but the strong motion inversion may include a trade-off between slip location and rupture time and the geodetic inversion does not have sufficient resolution for far slips. We then carred out a joint inversion of the two datasets in order to overcome these weaknesses of the single dataset inversions. The resultant slip distribution still retains the simple pattern and has a seismic moment of 2.2 × 1021 N·m (Mw 8.2). The asperity, with a peak slip of 7.1 m, is located in the center of the fault plane 50 km away from the hypocenter in the down-dip direction. The slip rate functions on subfaults around the hypocenter and asperity indicate that the rupture propagated with a supershear speed on the upper part of the fault plane and slowed down to 100–90% of the S-wave velocity on the middle and lower parts. These simple slip patterns and near-supershear rupture may imply the maturity of the Hokkaido subduction zone around the source region.
Akaike, H., Likelihood and Bayes procedure, in Bayesian Statistics, edited by J. M. Bernardo et al., pp. 143–166, Univ. Press, Valencia, Spain, 1980.
Aoi, S., K. Obara, S. Hori, K. Kasahara and Y. Okada, New strong-motion observation network: KiK-net, Eos Trans. AGU, 81 (48), Fall Meet. Suppl., Abstract S71A-05, 2000.
Archuleta, R. J., A faulting model for the 1979 Imperial Valley earthquake, J. Geophys. Res., 89, 4559–4585, 1984.
Bouchon, M., N. Toksöz, H. Karabulut, M.-P. Bouin, M. Dietrich, M. Aktar and M. Edie, Seismic imaging of the 1999 Izmit (Turkey) rupture inferred from the near-fault recordings, Geophys. Res. Lett., 27, 3013–3016, 2000.
Earthquake Research Committee, Long-term evaluation of earthquakes along the Kuril trench, http://www.jishin.go.jp/main/chousa/03_mar_chishima/index.htm, Headquarters for Earthquake Research Promotion, Tokyo, 2003.
Geographical Survey Institute, Crustal deformation of Japan detected GEONET, http://mekira.gsi.go.jp/ENGLISH/index.html, 1998.
Ide, S., Source process of the 2003 Tokachi-oki earthquake using strong motion and ocean bottom waveforms—Fast rupture exceeds the S-wave velocity?, Prog. Abst. Seismol. Soc. Jpn., TP24, 2003.
Iwasaki, T, H. Shiobara, A. Nishizawa, T. Kanazawa, K. Suyehiro, N. Hirata, T. Urabe and H. Shimamura, A detailed subduction structure in the Kuril trench deduced from ocean bottom seismographic refraction studies, Tectonophys., 165, 315–336, 1
JMA, Some reports for the 2003 Tokachi-oki earthquake, http://www.seisvol.kishou.go.jp/eq/2003_09_26_tokachi/index.html, 2003.
Jonsson, S., H. Zebker, P. Segall and F. Amelung, Fault slip distribution of the 1999 Mw7.1 Hector Mine, California, earthquake, estimated from satellite radar and GPS measurements, Bull. Seismol. Soc. Am., 92, 1377–1389, 2002.
Katsumata, K., N. Wada, and M. Kasahara, Newly imaged shape of the deep seismic zone within the subducting Pacific plate beneath the Hokkaido corner, Japan-Kurile arc-arc junction, J. Geophys. Res., 108, 2565, doi:10.1029/2002JB002175, 2003.
Kinoshita, S., Kyoshin Net (K-NET), Seismol. Res. Lett., 69, 309–332, 1998.
Kohketsu, K., The extended reflectivity method for synthetic near-field seismograms, J. Phys. Earth, 33, 121–131, 1985.
Koketsu, K., T. Ohno, Y. Ikegami, Rupture process inversion using 3-D Green’s functions: the 1995 Kobe earthquake revisited, Eos Trans. AGU, 84(46), Fall Meet. Suppl., Abstract S42H-07, 2003.
Miyazaki, S. and T. Kato, Coseismic slip and afterslip distributions of the 2003 Tokachi-oki earthquake derived from the GEONET data, http://wwweprc.eri.u-tokyo.ac.jp/teru/Tokachi-oki/kato.html, 2003.
Murai, Y, S. Akiyama, K. Katsumata, T. Takanami, T. Yamashina, T. Watanabe, I. Cho, M. Tanaka, A. Kuwano, N. Wada, H. Shimamura, I. Furuya, D. Zhao and R. Sanda, Delamination structure imaged in the source area of the 1982 Urakawa-oki earthquake, Geophys. Res. Lett., 30, 1490, doi:10.1029/2002GL016459, 2003.
NIED, Earthquake mechanism information, http://www.hinet.bosai.go.jp/topics/miyagi030726/, 2003.
Olson, A. H. and R. J. Apsel, Finite faults and inverse theory with application to the 1979 Imperial Valley earthquake, Bull. Seismol. Soc. Am., 72, 1969–2001, 1982.
Rosakis, A. J., O. Samudrala and D. Coker, Cracks faster than the shear wave speed, Science, 284, 1337–1340, 1999.
Wald, D. J. and R. W. Graves, 2001, Resolution analysis of finite fault source inversion using one- and three-dimensional Green’s functions 2. Combining seismic and geodetic data, J. Geophys. Res., 106, 8767–8788, 2001.
Wald, D. J. and T. H. Heaton, Spatial and temporal distribution of slip for the 1992 Landers, California, earthquake, Bull. Seismol. Soc. Am., 82, 668–691, 1994.
Yamanaka, Y and M. Kikuchi, Source process of the recurrent Tokachi-oki earthquake on September 26, 2003, inferred from teleseismic body waves, Earth Planets Space, e21-e24, 2003.
Yoshida, S., K. Koketsu, B. Shibazaki, T. Sagiya, T. Kato and Y. Yoshida, Joint inversion of near- and far- field waveforms and geodetic data for the rupture process of the 1995 Kobe earthquake, J. Phys. Earth, 44, 437–454, 1996.
An erratum to this article is available at http://dx.doi.org/10.1186/BF03352504.
About this article
Cite this article
Koketsu, K., Hikima, K., Miyazaki, S. et al. Joint inversion of strong motion and geodetic data for the source process of the 2003 Tokachi-oki, Hokkaido, earthquake. Earth Planet Sp 56, 329–334 (2004). https://doi.org/10.1186/BF03353060
- Source process
- joint inversion
- strong motion data
- geodetic data