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Spatial distribution for moment tensor solutions of the 2003 Tokachi-oki earthquake (M JMA = 8.0) and aftershocks

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Abstract

The 2003 Tokachi-oki earthquake with M w 7.9 is the largest interplate earthquake occurred ever since the high dense broadband seismometer network, the National Research Institute for Earth Science and Disaster Prevention (NIED) F-net, has been established over Japan. We determine the spatial distribution of moment tensor solutions and centroid depths of the mainshock and aftershocks. All aftershocks are divided to three groups: (1) the thrust fault type whose nodal plane is similar to the main shock; (2) the other thrust type with nodal plane different from the main shock; and (3) the normal fault type. The type (1) shows a depth distribution inclined to NW gently, coincident to the upper boundary of descending Pacific Plate. The active area of the type (1) does not overlap with the co-seismic slip area of the main shock at all. On the other hand, the type (2) shows no characteristic depth distribution with centroid depth scattered above and beneath the upper plate boundary. The type (3) are distributed, mainly, at about 40 km depth above the upper plate boundary. P axes of some aftershocks occurred above the plate boundary show the direction from ENE-WSW to ESE-WNW that suggests the effect of the Hidaka collision.

References

  1. DeMets, C. Oblique convergence and deformation along the Kuril and Japan trenches, J. Geophys. Res., 97, 17615–17625, 1992.

  2. Earthquake Research Committee, Long-term evaluation of earthquakes along the Kuril trench (March 14 2003. corrected on August 14 2003), http://www.jishin.go.jp/main/chousa/03marchishima/index.htm, The Headquarters for Earthquake Research Promotion, 2003.

  3. Fukao, Y., Upper mantle P structure on the ocean side of the Japan-Kurile Arc, Geophys. J. R. Astron. Soc., 50, 621–642, 1977.

  4. Fukuyama, E., M. Ishida, S. Hori, S. Sekiguchi, and S. Watada, Broadband seismic observation conducted under the FREESIA Project, Rep. Nat’l Res. Inst. Earth Sci. Dsas. Prev., 57, 23–31, 1996.

  5. Fukuyama, E., M. Ishida, D. S. Dreger, and H. Kawai, Automated seismic moment tensor determinateion by using on-line broadband seismic waveforms, Zisin, 51, 149–156, 1998 (in Japanese with English abstract).

  6. Harvard CMT catalogue, http://www.seismology.harvard.edu/, Harvard University, 2003.

  7. Hasegawa, A., S. Horiuchi, and N. Umino, Seismic structure of the northeastern Japan convergent margin: A synthesis, J. Geophys. Res., 99, 22295–22311, 1994.

  8. Heki, K., Displacement of Kashima Very Long Baseline Interferometry Station with respect to the North American Plate, J. Geod. Soc. Japan, 35, 97–104, 1989.

  9. Hino, R., S. Ito, H. Shiobara, H. Shiobara, H. Shimamura, T. Sato, T. Kanazawa, J. Kasahara, and A. Hasegawa, Aftershock distribution of the 1994 Sanriku-oki earthquake (Mw7.7) revealed by ocean bottom seismographic observation, J. Geophys. Res., 105, 21697–21710, 2000.

  10. Honda, R., S. Aoi, N. Morikawa, H. Sekiguchi, T. Kunugi, and H. Fujiwara, Ground motion and rupture process of the 2003 Tokachi-oki Earthquake obtained from strong motion data of K-NET and KiK-net, Earth Planets Space, 56, this issue, 317–322, 2004.

  11. Japan Meteorological Agency, The Seismological and Volcanological Bulletin of Japan, Japan Meteorological Agency, Tokyo, 2003.

  12. 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., 10.1029/2002JB002175, 2003.

  13. Kimura, G., Oblique subduction and collision: Forearc tectonics of the Kuril arc, Geology, 14, 404–407, 1986.

  14. Koketsu, K., K. Hikima, S. Miyazaki, and S. Ide, Joint inversion of strong motion and geodetic data for the source process of the 2003 Tokachioki, Hokkaido, Earthquake, Earth Planets Space, 56, this issue, 329–334, 2004.

  15. Nakamura, K., Possible nascent trench along the eastern Japan Sea as the convergent boundary between Eurasian and North American plates, Bull. Earthquake Res. Inst., 58, 711–722, 1983 (in Japanese).

  16. Nakanishi, A., S. Miura, K. Obana, S. Kodaira, N. Takahashi, T. Tsuru, J. Park, Y. Kaneda, E. Kurashimo, N. Hirata, and T. Iwasaki, Crustal structure across the coseismic rupture zone of the 1973 Nemuro-oki earthquake ocurred in the Kuril trench, Abstracts for the 2001 Joint Meeting of Earth and Planetary Science, Sz-011, 2001.

  17. NIED Seismic Moment Tensor Catalogue, http://www.fnet.bosai.go.jp, National Research Institute for Earth Science and Disaster Prevention, 2003.

  18. Ukawa, M., M. Ishida, S. Matsumura, K. Kasahara, Hypocentrer determination method of the Kanto-Tokai observational network for microearthquakes, Rep. Nat’l Res. Inst. Earth Sci. Dsas. Prev., 53, 1–88, 1984 (in Japanese with English abstract).

  19. USGS moment tensor solutions, http://neic.usgs.gov/neis/FM/qmom.html, USGS, 2003.

  20. Utsu, T., Seismology, second edition, 310 pp, Kyoritsu Syuppan, Tokyo, 1984 (in Japanese).

  21. Wessel, P. and W. H. F. Smith, New version of the generic mapping tools released, EOS Trans. AGU, 76, 329, 1995.

  22. Yagi, Y., Source rupture process of the 2003 Tokachi-oki earthquake determined by joint inversion of teleseismic body wave and strong ground motion data, Earth Planets Space, 56, this issue, 311–316, 2004.

  23. Yagi, Y., M. Kikuchi, and T. Sagiya, Co-seismic slip, post-seismic slip, and aftershocks associated with two large earthquakes in 1996 in Hyuganada, Japan, Earth Planets Space, 53, 793–803, 2001.

  24. Yamanaka, Y. and M. Kikuchi, Source process of the recurrent Tokachioki earthquake on September 26, 2003, inferred from teleseismic body waves, Earth Planets Space, 55, e21–e24, 2003.

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Correspondence to Yoshihiro Ito.

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Key words

  • The 2003 Tokachi-oki Earthquake
  • moment tensor solution
  • aftershock
  • focal mechanism
  • subduction
  • collision