Skip to main content

Seismic reflection profiling across the Itoigawa-Shizuoka Tectonic Line at Matsumoto, Central Japan

Abstract

The Itoigawa-Shizuoka Tectonic Line (ISTL) in Central Japan is a fault zone with a very high slip rate during Pliocene-Quaternary time. Our seismic reflection and gravity surveys across the northern segment of the ISTL at Matsumoto have revealed its geometry to a depth of 5 km. The fault plane was found to be of fairly low angle, in spite of the surface geologic observations that late Quaternary movements on this fault zone are dominantly strike slip. Partitioning of slip is taking place between the East Boundary Fault (thrust) and the Gofukuji Fault (left-slip), which constitute the fault zone and are parallel to and a few km apart from each other. However, these two faults are found to merge down-dip at a depth as shallow as 1.5 km below the surface. The geometry of the ISTL is significantly discordant with the orientation of the maximum shear stress acting regionally on Central Japan, indicating that the fault plane is of very low strength.

References

  1. Furuse, N. and Y. Kono, Slab residual gravity anomaly: Gravity reduction due to subducting plates beneath the Japanese Islands, J. Geodynamics, 36, 497–514, 2003.

    Article  Google Scholar 

  2. Hagiwara, Y., Analyses of gravity values in Japan, Bull. Earthq. Res. Inst., 45, 1091–1228, 1967.

    Google Scholar 

  3. Hagiwara, Y., N. Yamashita, T. Kosaka, K. Yano, and T. Yasui, Gravity observations along the Itoigawa-Shizuoka Geotectonic Line (I): An evaluation of the Bouguer anomaly in the Matsumoto Basin, Nagano Prefecure, Central Japan, Bull. Earthq. Res. Inst., Univ. Tokyo, 61, 537–550, 1986 (in Japanese).

    Google Scholar 

  4. Ikami, A., T. Yoshii, S. Kubota, Y. Sasaki, A. Hasemi, T. Moriya, H. Miyamachi, R. S. Matsu’ura, and K. Wada, A seismic-refraction profile in and around Nagano Prefecture, central Japan, J. Phys. Earth, 34, 457–474, 1986.

    Article  Google Scholar 

  5. Ikeda, Y. and T. Kumamoto, Shallow subsurface geometry of Active faults along the Itoigawa-Shizuoka Tectonic Line, central Japan, determined from closely spaced gravity survey, EOS (Transactions), 75, 674, 1994.

    Google Scholar 

  6. Ikeda, Y. and N. Yonekura, Determination of late Quaternary rates of net slip on two major fault zones in Central Japan, Bull. Dept. Geography, Univ. Tokyo, 18, 49–63, 1986.

    Google Scholar 

  7. Ikeda, Y., T. Imaizumi, M. Togo, K. Hirakawa, T. Miyauchi, and H. Sato (eds.), Atlas of Quaternary Thrust Faults in Japan, 254 pp., Univ. of Tokyo Press, Tokyo, 2002 (in Japanese)

    Google Scholar 

  8. Kato, H., Fossa Magna—A masked border region separating southwest and northeast Japan, Bull. Geol. Surv. Japan, 43, 1–30, 1992.

    Google Scholar 

  9. Kono, Y., Gravity anomalies well correlated with geological structures in central Japan: Conrad-Moho-slab residual Bouguer anomalies (CMS RAB), Chikyu (Earth Monthly), 25, 953–960, 2003 (in Japanese).

    Google Scholar 

  10. Kumamoto, T. and Y. Ikeda, Fault geometry and net slip of low angle thrust faults in the Kofu basin, central Japan, Zisin (J. Seism. Soc. Japan), 46, 245–258, 1993.

    Google Scholar 

  11. Matsuta, N., Structure and Behavior of the Itoigawa-Shizuoka Tectonic Line, Central Japan, in Quaternary Time: Partitioning of Slip on an Oblique-Slip Fault Zone, PhD Thesis, 155 p., Univ. Tokyo, 2002.

    Google Scholar 

  12. 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 

  13. Okubo, S., Y. Ikeda, T. Kumamoto, G. Seta, N. Matsuta, H. Chiba, and Y. Arai, 2-D and 3-D subsurface density structure in the northern part of the Itoigawa-Shizuoka Tectonic Line derived by gravity surveying, J. Geod. Soc. Japan, 46, 177–186, 2000 (in Japanese with English abstract).

    Google Scholar 

  14. Okumura, K., Paleoseismology of the Itoigawa-Shizuoka tectonic line in central Japan, J. Seismol., 5, 411–431, 2001.

    Article  Google Scholar 

  15. Sagiya, T., T. Nishimura, Y. Iio, and T. Tada, Crustal deformation around the northern and central Itoigawa-Shizuoka Tectonic Line, Earth Planets Space, 54, 1059–1063, 2002.

    Article  Google Scholar 

  16. Sato, H. and Y. Ikeda, Major fault systems in northern Honshu, Japan, Chikyu (Earth Monthly), 21, 569–575, 1999a (in Japanese).

    Google Scholar 

  17. Sato, H. and Y. Ikeda, Crustal structure and extensional tectonics in northern Honshu, Japan, Chikyu (Earth Monthly), 27, 135–141, 1999b (in Japanese).

    Google Scholar 

  18. Sato, H., T. Iwasaki, S. Kawasaki, Y. Ikeda, N. Matsuta, T. Takeda, N. Hirata, and T. Kawanaka, Formation and shortening deformation of a back-arc rift basin revealed by deep seismic profiling, central Japan, Tectonophysics, 388, 47–58, 2004 (submitted).

    Article  Google Scholar 

  19. Yano, T., Late Cenozoic geohistory in the Northern Fossa magna Region, Central Japan, J. Sci. Hiroshima Univ., C9, 81–132, 1986.

    Google Scholar 

Download references

Author information

Affiliations

Authors

Corresponding author

Correspondence to Yasutaka Ikeda.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Ikeda, Y., Iwasaki, T., Sato, H. et al. Seismic reflection profiling across the Itoigawa-Shizuoka Tectonic Line at Matsumoto, Central Japan. Earth Planet Sp 56, 1315–1321 (2004). https://doi.org/10.1186/BF03353356

Download citation

Key words

  • Itoigawa-Shizuoka Tectonic Line
  • active fault
  • seismic reflection profiling
  • slip partitioning
  • oblique slip
  • tectonic inversion