Skip to main content

Resistivity imaging across the source region of the 2004 Mid-Niigata Prefecture earthquake (M6.8), central Japan

Abstract

Across the source region of the 2004 Mid-Niigata Prefecture earthquake, wideband magnetotelluric (MT) survey was performed just after the onset of the mainshock. Owing to the temporal stop of the DC powered railways around the area together with intense geomagnetic activity, we obtain MT records with excellent quality for both short and long period data, as long as 10,000 s. Two dimensional regional strike is evaluated with the aid of the Groom-Bailey tensor decomposition together with induction vector analysis. As a result, N15°W is determined for the strike. This strike is oblique to the local geological trend and also to the strike of the main shock source fault together with aftershock distribution of N35°E. Two dimensional resistivity structure is determined with the aid of an ABIC inversion code, where static shift is considered and estimated. Characteristics of the structure are as follows. (1) About 10 km thick sedimentary layer exists on the top. (2) A conductive body exists in the lower crust beneath the source region. The mainshock occurred at the boundary of the conductive sedimentary layer and a resistive basement beneath it and aftershocks occurred in the sedimentary layer. From geological studies, it is reported that the sedimentary layer was formed in the extensional rift-structure from Miocene to Pleistocene and has been thickened by compressional tectonic regime in the late Quaternary. Interstitial fluids or clay minerals, which reduce the sedimentary layer resistivity, control the reactivation of the normal fault as the mainshock thrust fault and aftershock activity. The second conductive body probably indicates existence of fluids in the depths as well. Such a conductive layer in the lower crust was also revealed by previous MT experiments along the Niigata-Kobe Tectonic Zone and probably plays a main role in concentration of strain rate along the zone.

References

  1. Gamble, T. D., J. Clarke, and W. M. Goubau, Magnetotellurics with a remote magnetic reference, Geophysics, 44, 53–68, 1979.

    Article  Google Scholar 

  2. Goldstein, M. A. and D. W. Strangway, Audio-frequency magnetotellurics with a grounded electric dipole source, Geophysics, 40, 669–683, 1975.

    Article  Google Scholar 

  3. Goto, T., Y. Wada, N. Oshiman, and N. Sumitomo, Resistivity structure of a seismic gap along the Atotsugawa fault, Phys. Earth Planet. Inter., 148, 55–72, 2005.

    Article  Google Scholar 

  4. Groom, R. W. and R. C. Bailey, Decomposition of magnetotelluric impedance tensors in the presence of local three-dimensional galvanic distortions, J. Geophys. Res., 94, 1913–1925, 1989.

    Article  Google Scholar 

  5. Heki, K. and S. Miyazaki, Plate convergence and long-term crustal deformation in Central Japan, Geophys. Res. Lett., 28, 2313–2316, 2001.

    Article  Google Scholar 

  6. Hirata, N., H. Sato, and Research Group for the Urgent Aftershock of the Earthquake Research Institute, University of Tokyo, The 2004 Mid- Niigata Prefecture Earthquake—Source faults estimated by the subsurface structure and aftershocks, Kagaku, 75, 149–151, 2005a (in Japanese).

    Google Scholar 

  7. Hirata, N., H. Sato, S. Sakai, A. Kato, and E. Kurashimo, Fault system of the 2004 Mid Niigata Prefecture Earthquake and its aftershocks, Landslides, 2, doi:10.1007/s10346-005-0050-8, 2005b.

    Google Scholar 

  8. Hyodo, M. and K. Hirahara, A viscoelastic model of interseismic strain concentration in Niigata-Kobe Tectonic Zone of central Japan, Earth Planets Space, 55, 667–675, 2003.

    Article  Google Scholar 

  9. Iio, Y., T. Sagiya, Y. Kobayashi, and I. Shiozaki, Water-weakened lower crust and its role in the concentrated deformation in the Japanese Islands, Earth Planet. Sci. Lett., 203, 245–253, 2002.

    Article  Google Scholar 

  10. Japan National Oil Corp., Research report on the pilot drilling at “Higashi- Kubiki” for prospecting petroleum and natural gas in Japan, 1991 (in Japanese).

    Google Scholar 

  11. Kariya, K. A. and T. J. Shankland, Electrical conductivity of dry lower crustal rocks, Geophysics, 48, 52–61, 1983.

    Article  Google Scholar 

  12. Kasaya, T., N. Oshiman, N. Sumitomo, M. Uyeshima, Y. Iio, and D. Uehara, Resistivity structure around the hypocentral area of the 1984 Western Nagano Prefecture earthquake in central Japan, Earth Planets Space, 54, 107–118, 2002.

    Article  Google Scholar 

  13. Kato, A., E. Kurashimo, N. Hirata, S. Sakai, T. Iwasaki, and T. Kanazawa, Imaging the source region of the 2004 mid-Niigata prefecture earthquake and the evolution of a seismogenic thrust-related fold, Geophys. Res. Lett., doi:10.1029/2005GL022366, 2005.

    Google Scholar 

  14. Komazawa, M., High-resolution Bouguer gravity anomaly map around the source region of the 2004 mid-Niigata prefecture earthquake on the web:http://unit.aist.go.jp/igg/rg/geophysmap-rg/grav/niigatagravfig.html, Institute of Geology and Geoinformation, AIST, 2004.

    Google Scholar 

  15. Matsushima, M., Y. Honkura, N. Oshiman, S. Baris, M. K. Tuncer, S. B. Tank, C. Celik, F. Takahashi, M. Nakanishi, R. Yoshimura, R. Pektas, T. Komut, E. Tolak, A. Ito, Y. Lio, and A. M. Isikara, Seismoelectromagnetic effect associated with the Izmit earthquake and its aftershocks, Bull. Seis. Soc. Am., 92, 350–360, 2002.

    Article  Google Scholar 

  16. Mitsuhata, Y., Y. Ogawa Y., M. Mishina, T. Kono, T. Yokokura, and T. Uchida, Electromagnetic heterogeneity of the seismogenic region of 1962 M6.5 Northern Miyagi Earthquake, northeastern Japan, Geophys. Res. Lett., 28, 4371–4374, 2001.

    Article  Google Scholar 

  17. Ogawa, Y. and Y. Honkura, Mid-crustal electrical conductors and their correlations to seismicity and deformation at Itoigawa-Shizuoka Tectonic Line, Central Japan, Earth Planets Space, 56, 1285–1291, 2004.

    Article  Google Scholar 

  18. Ogawa, Y. and T. Uchida, A two-dimensional magnetotelluric inversion assuming Gaussian static shift, Geophys. J. Int., 126, 69–76, 1996.

    Article  Google Scholar 

  19. Ogawa, Y., M. Mishina, T. Goto, H. Satoh, N. Oshiman, T. Kasaya, Y. Takahashi, T. Nisitani, S. Sakanaka, M. Uyeshima, Y. Takahashi, Y. Honkura, and M. Matsushima, Magnetotelluric imaging of fluids in intraplate earthquakes zones, NE Japan back arc, Geophys. Res. Lett., 28, 3741–3744, 2001.

    Article  Google Scholar 

  20. Ogawa, Y., S. Takakura, and Y. Honkura, Resistivity structure across Itoigawa-Shizuoka tectonic line and its implications for concentrated deformation, Earth Planets Space, 54, 1115–1120, 2002.

    Article  Google Scholar 

  21. Sagiya, T., S. Miyazaki, and T. Tada, Continuous GPS array and presentday crustal deformation of Japan, Pure Appl. Geophys., 157, 2303–2322, 2000.

    Google Scholar 

  22. Sakai. S., N. Hirata, A. Kato, E. Kurashimo, T. Iwasaki, and T. Kanazawa, Multi-fault system of the 2004 Mid-Niigata Prefecture Earthquake and its aftershocks, Earth Planet Space, 57, this issue, 417–422, 2005.

    Article  Google Scholar 

  23. Sato, H., The relationship between late Cenozoic tectonic events and stress field and basin development in northeastern Japan, J. Geophys. Res., 99, 22261–22274, 1994.

    Article  Google Scholar 

  24. Sibson, R. H., Rupture nucleation on unfavorably oriented faults, Bull. Seis. Soc. Am., 80, 1580–1604, 1990.

    Google Scholar 

  25. Siripunvaraporn, W., G. Egbert, Y. Lenbury, and M. Uyeshima, Threedimensional magnetotelluric inversion: data-space method, Phys. Earth Planet. Int., 150, 3–14, 2005a.

    Article  Google Scholar 

  26. Siripunvaraporn, W., G. Egbert, and M. Uyeshima, Interpretation of 2-D magnetotelluric data with 3-D inversion, Geophys. J. Int., 160, 804–814, 2005b.

    Article  Google Scholar 

  27. Takakura, S., Resistivity of Neogene rocks in the Niigata and the Akita oil fields, Japan, BUTSURI-TANSA, 48, 161–175, 1995 (in Japanese with English abstract).

    Google Scholar 

  28. Takakura, S., K. Nakagami, Y. Mitsuhata, and R. Murayama, Petroleum geological interpretation of resistivity structure based on magnetotelluric and deep well data in the Higashi-Kubiki area, Niigata, Japan, J. Jpn. Assoc. Petrol. Tech., 62, 59–69, 1997 (in Japanese with English abstract).

    Article  Google Scholar 

  29. Yanagisawa, Y., I. Kobayashi, K. Takeuchi, M. Tateishi, K. Chihara, and H. Kato Geological Sheet Map 1:50,000 “Ojiya”, Geological Survey of Japan, 1986.

    Google Scholar 

Download references

Author information

Affiliations

Authors

Corresponding author

Correspondence to Makoto Uyeshima.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Uyeshima, M., Ogawa, Y., Honkura, Y. et al. Resistivity imaging across the source region of the 2004 Mid-Niigata Prefecture earthquake (M6.8), central Japan. Earth Planet Sp 57, 441–446 (2005). https://doi.org/10.1186/BF03351831

Download citation

Key words

  • Resistivity structure
  • magnetotelluric sounding
  • 2004 Mid-Niigata Prefecture earthquake
  • water
  • clay minerals
  • Niigata-Kobe Tectonic Zone