Skip to main content

Volume 56 Supplement 3

Special Issue: Special section for the 2003 Tokachi-oki earthquake

Low frequency events occurred during the sequence of aftershock activity of the 2003 Tokachi-Oki earthquake; a dynamic process of the tectonic erosion by subducted seamount

Abstract

During the sequence of aftershock activity of the 2003 Tokachi-Oki earthquake, anomalous events predominant in low-frequency components occurred very close to a subducted seamount around the junction between the Kuril Trench and the Japan Trench. The low-frequency wave train in the coda part reflects the strong excitation of surface waves and the source depth is considered to be very shallow. The focal mechanism of the low-frequency event is a type of the reverse fault. Considering with the source depth and the mechanism, the low-frequency event might have occurred on the plate boundary as a dynamic process of the tectonic erosion by the subducted seamount.

References

  • 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, Tokyo, 2003.

    Google Scholar 

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

    Article  Google Scholar 

  • Hyndman, R. D., M. Yamano, and D. A. Oleskevich, The seismogenic zone of subduction thrust faults, The Island Arc, 6, 244–260, 1997.

    Article  Google Scholar 

  • Ito, Y., H. Matsubayashi, H. Kimura, T. Matsumoto, Y. Asano, and S. Sekiguchi, Spatial distribution for moment tensor solutions of the 2003 Tokachi-oki earthquake (MJMA=8.0) and aftershocks, Earth Planets Space, 56, this issue, 301–306, 2004.

    Article  Google Scholar 

  • JMA, Sketch of the Tokachi-Oki earthquake in 2003, Reports of the Coordinating Committee for Earthquake Prediction, 71, 84–95, 2004.

    Google Scholar 

  • KAIKO I Research Group, Topography and structure of trenches around Japan—Data atlas of France-Japanese KAIKO project, Phase I., University of Tokyo Press, Tokyo, 305 pp., 1986.

    Google Scholar 

  • 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., 2004 (in press).

    Google Scholar 

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

    Article  Google Scholar 

  • Kuramoto, S., A. Taira, N. L. Bangs, T. H. Shipley, G. F. Moore, and EW99-07, 08 Scientific Parites, Seismogenic zone in the Nankai accretionary wedge: General summary of Japan-U.S. collaborative 3-D seismic investigation, J. Geography, 109, 531–539, 2000 (in Japanese with English abstract).

    Article  Google Scholar 

  • Moore, J. C., N. B. Klaus, B. Bekins, C. J. Bucker, W. Bruckmann, S. N. Erickson, O. Hansen, T. Horton, P. Ireland, C. O. Major, G. F. Moore, S. Peacok, S. Saito, E. J. Screaton, J. W. Shimeld, P. H. Stauffer, T. Taymaz, P. A. Teas, and T. Tokunaga, Consolidation patterns during initiation and evolution of plate-boundary decollement zone: Northern Barbados accretionary prism, Geology, 26, 811–814, 1998.

    Article  Google Scholar 

  • NIED Hi-net, Special page for the 2003 Tokachi-Oki earthquake, http://www.hinet.bosai.go.jp/topics/tokachi0309/, 2003.

    Google Scholar 

  • Von Huene, R. and R. Culotta, Tectonic erosion at the front of the Japan Trench convergent margin, Tectonophysics, 160, 75–90, 1989.

    Article  Google Scholar 

  • Wessel, P. and W. H. F. Smith, Free software helps map and display data, Eos Trans. AGU, 72, 445–446, 1991.

    Article  Google Scholar 

  • Yagi, Y., Source rupture process of the Tokachi-oki earthquake of September 26 2003, determined by joint inversion of teleseismic body wave and strong motion data, Earth Planets Space, 56, this issue, 311–316, 2004.

    Article  Google Scholar 

  • 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, 55, e21–e24, 2003.

    Article  Google Scholar 

  • Yamazaki, T. and Y. Okamura, Subducting seamounts and deformation of overriding forearc wedges around Japan, Tectonophysics, 160, 207–229, 1989.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Kazushige Obara.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Obara, K., Haryu, Y., Ito, Y. et al. Low frequency events occurred during the sequence of aftershock activity of the 2003 Tokachi-Oki earthquake; a dynamic process of the tectonic erosion by subducted seamount. Earth Planet Sp 56, 347–351 (2004). https://doi.org/10.1186/BF03353063

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1186/BF03353063

Key words

  • Low-frequency earthquake
  • 2003 Tokachi-Oki earthquake
  • subduction zone
  • tectonic erosion
  • seamount
  • plate boundary