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Interseismic deformation of the Nankai subduction zone, southwest Japan, inferred from three-dimensional crustal velocity fields


We have studied crustal deformation in the Nankai subduction zone, southwest Japan, based on three-dimensional GPS velocity fields. Oblique subduction of the Philippine Sea plate has caused two different modes of deformation of the overriding plate: interseismic crustal shortening in the direction of plate convergence, and permanent lateral movement of the forearc. The block boundary dividing the forearc is the Median Tectonic Line (MTL); however, we assumed that its shallower portion is fully or partially locked to a certain depth. The plate boundary and the MTL are represented by many rectangular faults. We carried out inversion analyses with a priori information to estimate simultaneously slip deficit rates at those rectangular faults, together with the rate of lateral movement of the forearc. The results show that the seismogenic subduction faults at a depth of 5–25 km are strongly locked. As for the transition zone at 25–35 km, the inversion analysis results in stronger locking than shown in previous studies, especially when the vertical velocity data are weighted. The rates of lateral forearc movement and slip deficit at the MTL are nearly comparable but in a reverse sense to each other. This shows that the shallower portion of the MTL is strongly locked but that stationary aseismic slip is occurring in the deeper part.


  • Aoki. Y. and C. H. Scholz, Vertical deformation of the Japanese islands, 1996–1999, J. Geophys. Res., 108, doi:10.1029/2002JB002129, 2003a.

  • Aoki. Y. and C. H. Scholz, Interseismic deformation at the Nankai subduction zone and the Median Tectonic Line, southwest Japan, J. Geophys. Res., 108, doi:10.1029/2003JB002441, 2003b.

  • DeMets, C., R. G. Gordon, D. F. Argus, and S. Stein, Effect of recent revisions to the geomagnetic reversal time scale on estimates of current plate motions, Geophys. Res. Lett., 21, 2191–2194, 1994.

    Article  Google Scholar 

  • Hatanaka, Y., T. Iizuka, M. Sawada, A. Yamagiwa, Y. Kikuta, J. M. Johnson, and C. Rocken, Improvement of the analysis strategy of GEONET, Bull. Geogr. Surv. Inst., 49, 1–35, 2003.

    Google Scholar 

  • Heki, K., S. Miyazaki, H. Takahashi, M. Kasahara, F. Kimata, S. Miura, N. F. Vasilenko, A. Ivashchenko, and K-D. An, The Amurian Plate motion and current kinematics in eastern Asia, J. Geophys. Res., 104, 29,147–29,155, 1999.

    Article  Google Scholar 

  • Hirose, H., K. Hirahara, F. Kimata, N. Fujii, and S. Miyazaki, A slow thrust slip event following the two 1996 Hyuganada earthquakes beneath the Bungo Channel, southwest Japan, Geophys. Res. Lett., 26, 3237–3240, 1999.

    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 

  • Ito, T. and M. Hashimoto, Spatiotemporal distribution of interplate coupling in southwest Japan from inversion of geodetic data, J. Geophys. Res., 109, B02315, doi:10.1029/2002JB002358, 2004.

    Google Scholar 

  • Kawamura, T., M. Onishi, E. Kurashimo, T. Ikawa, and T. Ito, Deep seismic reflection experiment using a dense receiver and sparse shot technique for imaging the deep structure of the Median Tectonic Line (MTL) in east Shikoku, Japan, Earth Planets Space, 55, 549–557, 2003.

    Article  Google Scholar 

  • Matsu’ura, M., D. D. Jackson, and A. Chen, Dislocation model for aseis-mic crustal deformation at Holister, California, J. Geophys. Res., 91, 12,661–12,674, 1986.

    Article  Google Scholar 

  • Mazzotti, S., X. Le Pichon, P. Henry, and S. Miyazaki, Full interseismic locking of the Nankai and Japan-west Kurile subduction zones: An analysis of uniform elastic strain accumulation in Japan constrained by permanent GPS, J. Geophys. Res., 105, 13,159–13,177, 2000.

    Article  Google Scholar 

  • McCaffrey, R., Estimates of modern arc-parallel strain rates in fore arcs, Geology, 24, 1139–1142, 1996.

    Article  Google Scholar 

  • Miyazaki, S. and K. Heki, Crustal velocity field of southwest Japan: Subduction and arc-arc collision, J. Geophys. Res., 106, 4305–4326, 2001.

    Article  Google Scholar 

  • Murakami, M. and S. Ozawa, Mapped vertical deformation field of Japan derived from continuous GPS measurements and its tectonic implications, J. Seism. Soc. Jpn, 57, 209–231, 2004 (in Japanese).

    Google Scholar 

  • Okada, Y., Surface deformation due to shear and tensile faults in a halfspace, Bull. Seism. Soc. Am., 75, 1135–1154, 1985.

    Google Scholar 

  • Ozawa, S., Y. Hatanaka, M. Kaidzu, M. Murakami, T. Imakiire, and Y. Ishigaki, Aseismic slip and low-frequency earthquakes in the Bungo channel, southwestern Japan, Geophys. Res. Lett., 31, L07609, doi:10. 1029/2003GL019381, 2004.

    Article  Google Scholar 

  • Research Group for Active Faults of Japan, Active Faults in Japan: Sheet Maps and Inventories, 437pp, Univ. Tokyo Press, Tokyo, 1991 (in Japanese).

    Google Scholar 

  • Sagiya, T., A decade of GEONET: 1994–2003—The continuous GPS observation in Japan and its impact on earthqauke studies—, Earth Planets Space, 56, xxix–xli, 2004.

    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 

  • Sella, G. F., T. H. Dixon, and A. Mao, REVEL: A model for Recent plate velocities from space geodesy, J. Geophys. Res., 107, doi:10. 1029/2000JB000033, 2002.

  • Suwa, Y., S. Miura, A. Hasegawa, T. Sato, and K. Tachibana, Interplate coupling beneath NE Japan inferred from three-dimensional displacement field, J. Geophys. Res., 111, B04402, doi:10.1029/2004JB003203, 2006.

    Google Scholar 

  • Tabei, T., M. Hashimoto, S. Miyazaki, K. Hirahara, F. Kimata, T. Matsushima, T. Tanaka, Y. Eguchi, T. Takaya, Y. Hoso, F. Ohya, and T. Kato, Subsurface structure and faulting of the Median Tectonic Line, southwest Japan inferred from GPS velocity field, Earth Planets Space, 54, 1065–1070, 2002.

    Article  Google Scholar 

  • Tsutsumi, H. and A. Okada, Segmentation and Holocene surface faulting on the Median Tectonic Line, southwest Japan, J. Geophys. Res., 101, 5855–5871, 1996.

    Article  Google Scholar 

  • Wang, K., R. Wells, S. Mazzotti, R. D. Hyndman, and T. Sagiya, A revised dislocation model of interseismic deformation of the Cascadia subduction zone, J. Geophys. Res., 108, 2026, doi:10.1029/2001JB001227, 2003.

    Article  Google Scholar 

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Correspondence to Takao Tabei.

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Tabei, T., Adachi, M., Miyazaki, S. et al. Interseismic deformation of the Nankai subduction zone, southwest Japan, inferred from three-dimensional crustal velocity fields. Earth Planet Sp 59, 1073–1082 (2007).

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