Skip to main content
Earth, Planets and Space
Download PDF

Volume 53 Supplement 4

Special Issue: Great Subduction Zone Earthquakes

  • Article
  • Published:

Splay fault and megathrust earthquake slip in the Nankai Trough

Earth, Planets and Space volume 53, pages 243–248 (2001)Cite this article

Abstract

We consider whether splay fault slip may be a factor influencing the behavior of megathrust earthquakes in the Nankai Trough. Consideration of tsunami inversion results from other studies indicates that slip on one or more splay faults may be particularly important for the segment of the Nankai Trough offshore western Shikoku. These results suggest that during at least two megathrust earthquakes substantial slip may have occurred on one or more splay faults which cut the island arc crust over 100 km landward of the trench axis. In contrast to smaller subsidiary thrusts in the semi-consolidated and unconsolidated sediments very near the trough axis, the crustal faults considered here could accumulate and release considerable tectonic stress. Through a simple finite element calculation we demonstrate that slip on such faults can release some of the shear stress on the megathrust accumulated through plate subduction, and therefore may have some influence on the behavior of megathrust earthquakes.

References

  • Aida, I., Numerical experiments of historical tsunamis generated off the coast of the Tokaido district, Bull. Earthq. Res. Inst., 56, 715–730, 1981 (in Japanese).

    Google Scholar 

  • Ando, M., Source mechanisms and tectonic significance of historical earthquakes along the Nankai Trough, Japan, Tectonophys., 27, 119–140, 1975.

    Article  Google Scholar 

  • Clarke, S. H. and G. A. Carver, Late Holocene Tectonics andpaleoseismicity, southern Cascadia subduction zone, Science, 255, 188–192, 1992.

    Article  Google Scholar 

  • Cummins, P. R. and Y. Kaneda, Possible splay fault slip during the 1946 Nankai earthquake, Geophys. Res. Lett., 27, 2725–2728, 2000.

    Article  Google Scholar 

  • Hyndman, R. D., K. Wang, and M. Yamano, Thermal constraints on the seismogenic portion of the southwestern Japan subduction thrust, J. Geophys. Res., 100, 15,373–15,392, 1995.

    Article  Google Scholar 

  • Kagami, H., K. Shiono, and A. Taira, Plate subduction and formation of the accretionary complex in the Nankai Trough, Kagaku, 53, 429–438, 1983 (in Japanese).

    Google Scholar 

  • Kanamori, H., Tectonic implications of the 1944 Tonankai and 1946 Nankaido earthquakes, Phys. Earth Planet. Inter., 5, 129–139, 1972.

    Article  Google Scholar 

  • Kodaira, S., N. Takahashi, J. Park, K. Mochizuki, M. Shinohara, and S. Kimura, The western Nankai Trough seismogenic zone: Result from wide-angle ocean-bottom seismographic survey, J. Geophys. Res., 105, 5887–5905, 2000.

    Article  Google Scholar 

  • McCaffrey, R., On the role of the upper plate in great subduction zone earthquakes, J. Geophys. Res., 98, 11,953–11,966, 1993.

    Article  Google Scholar 

  • Okada, Y., Internal deformation due to shear and tensile faults in a half-space, Bull. Seismol. Soc. Am., 82, 1018–1040, 1992.

    Google Scholar 

  • Plafker, G., Alaskan earthquake of 1964 and Chilean earthquake of 1960: implications for arc tectonics, J. Geophys. Res., 77, 901–923, 1972.

    Article  Google Scholar 

  • Sagiya, T. and W. Thatcher, Coseismic slip resolution along a plate boundary megathrust: The Nankai Trough, southwest Japan, J. Geophys. Res., 104, 1111–1129, 1999.

    Article  Google Scholar 

  • Savage, J. C., A dislocation model of strain accumulation and release at a subduction zone, J. Geophys. Res., 88, 4984–4996, 1983.

    Article  Google Scholar 

  • Seno, T., Syntheses of the regional stress fields of the Japanese islands, The Island Arc, 8, 66–79, 1999.

    Article  Google Scholar 

  • Stein, R. S. and G. C. P. King, Seismic potential revealed by surface folding: 1983 Coalinga, California, earthquake, Science, 224, 869–872, 1984.

    Article  Google Scholar 

  • Sugiyama, Y., Neotectonics of Southwest Japan due to the right-oblique subduction of the Philippine Sea plate, Geofis. Int., 33, 53–76, 1994.

    Google Scholar 

  • Tanioka, Y. and K. Satake, Coseismic slip distribution of the 1946 Nankai earthquake and aseismic slips caused by the earthquake, Earth Planets Space, 53, this issue, 235–241, 2001.

    Article  Google Scholar 

  • Wang, K. and J. He, Mechanics of low-stress forearcs: Nankai and Cascadia, J. Geophys. Res., 104, 15,191–15,205, 1999.

    Article  Google Scholar 

  • Wang, K., R. D. Hyndman, and M. Yamano, Thermal regime of the southwest Japan subduction zone: effects of age history of the subducting plate, Tectonophys., 248, 53–69, 1995.

    Article  Google Scholar 

  • Zienkiewicz, O. C. and R. L. Taylor, in The Finite Element Method, 648 pp., McGraw-Hill, London, 1997.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Frontier Research Program for Subduction Dynamics, Japan Marine Science and Technology Center, 2-15 Natsushima-cho, Yokosuka, Japan

    Phil R. Cummins, Takane Hori & Yoshiyuki Kaneda

Authors
  1. Phil R. Cummins
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Takane Hori
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yoshiyuki Kaneda
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Phil R. Cummins.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Cummins, P.R., Hori, T. & Kaneda, Y. Splay fault and megathrust earthquake slip in the Nankai Trough. Earth Planet Sp 53, 243–248 (2001). https://doi.org/10.1186/BF03352381

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1186/BF03352381

Keywords