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Well-resolved hypocenter distribution using the double-difference relocation method in the region of the 2007 Chuetsu-oki Earthquake


The 2007 Chuetsu-oki Earthquake (Mj = 6.8) occurred in the eastern margin of the Japan Sea where high strain rates have been observed and many large earthquakes have occurred. The main shock was located near the Western Nagaoka Basin active fault system dipping in the westward direction. We estimated the well-resolved hypocenter location around the main shock rupture zone from the differential arrival times obtained by both manual picking and waveform cross-correlation analysis. From the relocated aftershock distributions, we successfully resolved the detailed fault structures activated by the main shock. The estimated fault model resolves four individual fault segments. The fault model suggests that the main shock predominantly ruptured the southeastward dipping fault planes. On the other hand, the aftershocks around the hypocenter of the main shock occurred on both the northwestward and southeastward dipping fault planes. Both fault planes around the hypocenter of the main shock may have been nearly coincidentally ruptured during the main shock.


  1. Aoi, S., H. Sekiguchi, N. Morikawa, and T. Kunugi, Source process of the 2007 Niigata-ken Chuetsu-oki earthquake derived from near-fault strong motion data, Earth Planets Space, 60, this issue, 1131–1135, 2008.

    Article  Google Scholar 

  2. Hirata, N. and M. Matsu’ura, Maximum-likelihood estimation of hypocenter with origin time eliminated using nonlinear inversion technique, Phys. Earth Planet. Inter., 47, 50–61, 1987.

    Article  Google Scholar 

  3. Japan Meteorological Agency,, 2007.

  4. Kissling, E., W. L. Ellsworth, D. Eberhart-Phillips, and U. Kradolfer, Initial reference models in local earthquake tomography, J. Geophys. Res., 99, 19635–19646, 1994.

    Article  Google Scholar 

  5. Matsumoto, T., H. Matsubayashi, and T. Kazakami, F-net Moment Tensor Solution on The Niigataken Chuetsu-oki Earthquake in 2007, Seismol. Soc. Jpn. Programme. Abstr. Fall Meeting, 2007 (in Japanese).

    Google Scholar 

  6. Okamura, Y, S. Kuramoto, and M. Sato, Active structures and their relation to earthquakes along the eastern margin of the Japan Sea, Bull. Geol. Surv., 49, 1–18, 1998 (in Japanese with English abstract).

    Google Scholar 

  7. Ozawa, T., Coseismic deformatoin of the 2007 Chuetsu-oki earthquake derived from PALSAR/InSAR and its fault model, Earth Planets Space, 60, this issue, 1099–1104, 2008.

    Article  Google Scholar 

  8. Research Group for Active Faults of Japan, Active Faults in Japan, revised edition, 437 pp., University of Tokyo Press, Tokyo, 1991 (in Japanese).

    Google Scholar 

  9. Sagiya, T., S. Miyazaki, and T. Tada, Continuous GPS array and present-day crustal deformation of Japan, Pure Appl. Geophys., 157, 2303–2322, 2000.

    Google Scholar 

  10. Shearer, P., Improving local earthquake locations using the L1 norm and waveform cross correlation: Application to the Whittier Narrows, California, aftershock sequence, J. Geophys. Res., 102, 8269–8283, 1997.

    Article  Google Scholar 

  11. Shibutani, T., Y. Iio, S. Matsumoto, H. Katao, T. Matsushima, S. Ohmi, F. Takeuchi, K. Uehira, K. Nishigami, B. Enescu, I. Hirose, Y. Kano, Y Kohno, M. Korenaga, Y. Mamada, M. Miyazawa, T. Ueno, H. Wada, and Y Yukutake, Aftershock distribution of the 2004 Mid Niigata Prefecture Earthquake derived from a combined analysis of temporary online observations and permanent observations, Earth Planets Space, 57, 545–549, 2005.

    Article  Google Scholar 

  12. Takeda, T., H. Sato, T. Iwasaki, N. Matsuta, S. Sakai, T. Iidaka, and A. Kato, Crustal structure in the northern Fossa Magna region, central Japan, from refraction/wide-angle reflection data, Earth Planets Space, 56, 1239–1299, 2004.

    Article  Google Scholar 

  13. Townend, J. and M. D. Zoback, Stress, strain, and mountain building in central Japan, J. Geophys. Res., 111, doi:10.1029/2005JB003759, 2006.

  14. Waldhauser, F. and W. L. Ellsworth, A double-difference earthquake location algorithm: Method and application to the Northern Hayward fault, Bull. Seismol. Soc. Am., 90, 1352–1368, 2000.

    Article  Google Scholar 

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

    Article  Google Scholar 

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Correspondence to Yohei Yukutake.

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Yukutake, Y., Takeda, T. & Obara, K. Well-resolved hypocenter distribution using the double-difference relocation method in the region of the 2007 Chuetsu-oki Earthquake. Earth Planet Sp 60, 1105–1109 (2008).

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Key words

  • The 2007 Chuetsu-oki earthquake
  • aftershocks
  • hypoDD
  • fault structure