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Strong ground motions from an Mj 6.1 inland crustal earthquake in Hokkaido, Japan: the 2004 Rumoi earthquake


An inland crustal earthquake (Mj 6.1) occurred on December 14, 2004 in the northern part of Hokkaido, Japan. A large ground acceleration of 1127 cm/s2 and a large pseudo-velocity response of over 100 cm/s were recorded at the nearest strong-motion station, HKD020, about 10 km from the hypocenter. This large ground motion is considered to be attributable to the source effect and the site effect. The site effect is investigated using the traditional spectral ratio technique and the theoretical evaluation based on the subsurface structure model. The results imply that the site effect has an insignificant effect on the large ground motion at HKD020. The source effect is investigated by constructing the source model that explains the broad-band strong-motion records at four stations around the epicenter using the empirical Green’s function method. The estimated source model satisfies the empirical relationship between the strong motion generation areas and the seismic moment for inland crustal earthquakes. The high-frequency level of the acceleration source spectrum is also consistent with the empirical relationship. These results suggest that this earthquake is a normal crustal event and that the large ground motion at HKD020 is mainly attributable to the source effect, short distance from the strong motion generation area and the forward directivity effect. Finally, the temporal change of the site response at HKD020 is examined using long duration records including the main shock and several aftershocks. The site response based on the S-wave horizontal-to-vertical spectral ratio method shows the nonlinearity for the main shock and an aftershock occurring about 20 s after the main shock. However, the site response shows linearity for other later aftershocks. This site response change is attributed to the difference in ground motion amplitude.


  1. Aki, K. and P. G. Richards, Quantitative Seismology, 1, 557 pp., W. H. Freeman and Company, 1980.

  2. Aguirre, J. and K. Irikura, Nonlinearity, liquefaction, and velocity variation of soft soil layers in Port Island, Kobe, during the Hyogo-ken Nanbu earthquake, Bull. Seismol. Soc. Am., 87, 1244–1258, 1997.

  3. Borcherdt, R. D., Effects of local geology on ground motion near San Francisco Bay, Bull. Seismol. Soc. Am., 60, 29–61, 1970.

  4. Bouchon, M., A simple method to calculate Green’s functions for elastic layered media, Bull. Seismol. Soc. Am., 71, 959–971, 1981.

  5. Brune, N., Tectonic stress and the spectra of seismic shear waves from earthquakes, J. Geophys. Res., 75, 4997–5009, 1970.

  6. Brune, N., Correction, J. Geophys. Res., 76, 5002, 1971.

  7. Dan, K., M. Watanabe, T. Sato, and T. Ishii, Short-period source spectra inferred from variable-slip rupture models and modeling of earthquake faults for strong motion prediction by semi-empirical method, J. Struct. Contr. Eng. AIJ, 545, 51–62, 2001 (in Japanese with English abstract).

  8. Dan, K., T. Sato, and K. Irikura, Characterizing source model for strong motion prediction based on asperity model, Proc. 11th Jpn. Earthq. Eng. Symp., 555–560, 2002 (in Japanese with English abstract).

  9. Geographical Survey Institute,, 2004.

  10. Ichiyanagi, M., T. Maeda, T. Yamaguchi, H. Takahashi, M. Kasahara, T. Sasatani, and A. Yamamoto, Aftershock distribution of the December 14, 2004 Rumoi-nanbu earthquake (M 6.1) in the northern part of Hokkaido, Japan, Zisin 2, 59, 209–221, 2007 (in Japanese with English abstract).

  11. Irikura, K., Prediction of strong acceleration motions using empirical Green’s function, Proc. 7th Jpn. Earthq. Eng. Symp., 151–156, 1986.

  12. Irikura, K., T. Kagawa, and H. Sekiguchi, Revision of the empirical Green’s function method by Irikura (1986), Proc. Seismol. Soc. Jpn. 2, B25, 1997 (in Japanese).

  13. Kamae, K. and K. Irikura, Source model of the 1995 Hyogo-ken Nanbu earthquake and simulation of near-source ground motion, Bull. Seismol. Soc. Am., 88, 400–412, 1998.

  14. Kamae, K., K. Irikura, and Y. Fukuchi, Prediction of strong ground motion for M 7 earthquake using regional scaling relations of source parameters, J. Struct. Constr. Eng. AIJ, 416, 57–70, 1990 (in Japanese with English abstract).

  15. Kanno, T., A. Narita, N. Morikawa, H. Fujiwara, and Y. Fukushima, A new attenuation relation for strong ground motion in Japan based on recorded data, Bull. Seismol. Soc. Am., 96, 879–897, 2006.

  16. Liu, P., S. Custódio, and R. J. Archuleta, Kinematic inversion of the 2004 M 6.0 Parkfield earthquake including an approximation to site effects, Bull. Seismol. Soc. Am., 96, S143–S158, doi:10.1785/120050826, 2006.

  17. Maeda, T., T. Sasatani, M. Ichiyanagi, T. Yamaguchi, H. Takahashi, and M. Kasahara, The earthquake of December 14, 2004 (M 6.1) at southern Rumoi district, the northern part of Hokkaido, Geophys. Bull. Hokkaido Univ., 68, 243–253, 2005 (in Japanese with English abstract).

  18. Maeda, T., N. Takai, and T. Sasatani, Site effect on large ground motion at HKD020 during the 2004 Rumoi earthquake, Proc. Jpn. Assoc. Earthq. Eng., 2008 (in Japanese).

  19. Miyake, H., T. Iwata, and K. Irikura, Estimation of rupture propagation direction and strong motion generation area from azimuth and distance dependence of source amplitude spectra, Geophys. Res. Lett., 28, 2727–2730, 2001.

  20. Miyake, H., T. Iwata, and K. Irikura, Source characterization for broadband ground-motion simulation: kinematic heterogeneous source model and strong motion generation area, Bull. Seismol. Soc. Am., 93, 2531–2545, 2003.

  21. Moriya, T., Seismo-tectonics of Hokkaido based on shallow seismicity and focal mechanism studies, in Geology and Tectonics of Hokkaido, Monogr. Assoc. Geol. Collab. Jpn., 31, 475–485, 1986 (in Japanese with English abstract).

  22. Okada, H., The Microtremor Survey Method (Geophysical monographs series no. 12), 135 pp., Society of Exploration Geophysicists, 2003.

  23. Sapporo District Meteorological Observatory, Reports of the southern Rumoi district earthquake on December 14th, 2004, 2005 (in Japanese).

  24. Shakal, A., H. Haddadi, V. Graizer, K. Lin, and M. Huang, Some key features of the strong-motion data from the M 6.0 Parkfield, California, earthquake of 28 September 2004, Bull. Seismol. Soc. Am., 96, S90–S118, doi:10.1785/0120050817, 2006.

  25. Si, H. and S. Midorikawa, New attenuation relationships for peak ground acceleration and velocity considering effects of fault type and site condition, J. Struct. Constr. Eng. AIJ, 523, 63–70, 1999 (in Japanese with English abstract).

  26. Somerville, P., K. Irikura, R. Graves, S. Sawada, D. Wald, N. Abrahamson, Y. Iwasaki, T. Kagawa, N. Smith, and A. Kowada, Characterizing crustal earthquake slip models for the prediction of strong ground motion, Seismol. Res. Lett., 70, 59–80, 1999.

  27. Takahashi, H., M. Kasahara, F. Kimata, S. Miura, K. Heki, T. Seno, T. Kato, N. Vasilenko, A. Ivashchenko, V. Bahtiarov, V. Levin, E. Gordeev, F. Korchagin, and M. Gerasimenko, Velocity field of around the sea of Okhotsk and sea of Japan regions determined from a new continuous GPS network data, Geophys. Res. Lett., 26, 2533–2536, 1999.

  28. Takeo, M., Near-field synthetic seismograms taking into account the effects of anelasticity—the effects of anelastic attenuation on seismograms caused by a sedimentary layer—, Meteorol. Geophys., 36, 235–257, 1985 (in Japanese with English abstract).

  29. Tamura, M., G. Kawakami, T. Suzuki, N. Okazaki, and T. Oka, Preliminary observations on the 2004 Rumoi-shichou-nanbu earthquake—Geological damages, ground motion and the influence on hot spring well—, Report of the geological survey of Hokkaido, 76, 113–128, 2005 (in Japanese).

  30. Wen, K. L., T. M. Chang, C. M. Lin, and H. J. Chiang, Identification of nonlinear site response using the H/V spectral ratio method, Terr. Atmos. Ocean. Sci., 17, 533–546, 2006.

  31. Wessel, P. and W. H. Smith, New version of the Generic Mapping Tools released, EOS Trans. AGU, 329, 1995.

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Correspondence to Takahiro Maeda.

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Maeda, T., Sasatani, T. Strong ground motions from an Mj 6.1 inland crustal earthquake in Hokkaido, Japan: the 2004 Rumoi earthquake. Earth Planet Sp 61, 689–701 (2009).

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Key words

  • The 2004 Rumoi earthquake
  • strong ground motion
  • source model
  • empirical Green’s function method
  • site response