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Co-seismic and post-seismic pore-fluid pressure changes in the Philippine Sea plate and Nankai decollement in response to a seismogenic strain event off Kii Peninsula, Japan

Abstract

New pressure data from a pair of Ocean Drilling Program (ODP) hydrologic borehole observatories at ODP Sites 1173 and 808, located off Japan in the subducting Philippine Sea plate and in the nearby Nankai accretionary prism, respectively, show clear signals associated with an earthquake swarm off the Kii Peninsula that began on September 5, 2004, roughly 220 km away from the observatory sites. At Site 1173, formation pressures rose by 1.0–1.5 kPa at the time of the largest earthquake (Mw = 7.5), then continued to rise to a total anomaly of 4 kPa during the following 200–300 days. These transients are inferred to reflect co-seismic and slow continuing volumetric contraction of the plate by amounts of roughly 0.2 × 10−6 and 0.5 × 10−6, respectively. The sign of the estimated strain is consistent with that predicted with a seismic-moment-constrained elastic half-space dislocation model, but the amplitude is much larger, by roughly a factor of 6 at the time of the main earthquake, and by nearly a factor of 20 when the total pressure-estimated strain at the end of the post-seismic period is compared to that estimated from the total cumulative seismic moment including aftershocks. The simplest inference that can be drawn is that a large component of aseismic slip occurred in the epicentral area. At Site 808, pressure at the deepest monitoring zone just above the subduction decollement fell at the time of the largest earthquakes. This may reflect shear-induced dilatation which would be consistent with strain-or velocity-hardening behaviour along this seaward-most part of the subduction thrust interface.

References

  • Ashi, K., M. Okubo, H. Ishii, H. Aoki, T. Yamauchi, Y. Kitagawa, N. Koizumi, and S. Azuma, Co-seismic strain-steps associated with the 2004 off the Kii peninsula earthquakes observed with Ishii-type borehole strainmeters and quartz-tube extensometers, Earth Planets Space, 57, 309–314, 2005.

    Article  Google Scholar 

  • Bilek, S. and T. Lay, Rigidity variations with depth along interplate megathrust faults in subduction zones, Nature, 400, 443–446, 1999.

    Article  Google Scholar 

  • Bourlange, S., L. Jouniaux, and P. Henry, Data report: Permeability, compressibility, and friction coefficient measurements under confining pressure and strain, Leg 190, Nankai Trough, in Proc. ODP Sci. Results, edited by H. Mikada, G. Moore, A. Taira, K. Becker, J. Moore, and A. Klaus, 190/196, 1–16 (CD-ROM), 2005.

  • Davis, E. E. and K. Becker, On the fidelity of “CORK” borehole hydrologic observatory pressure records, Sci. Drill., 5, 54–59, 2007.

    Article  Google Scholar 

  • Davis, E. E., K. Wang, R. Thomson, K. Becker, and J. Cassidy, An episode of seafloor spreading and associated plate deformation inferred from crustal fluid pressure transients, J. Geophys. Res., 106, 21,953–21,963, 2001.

    Article  Google Scholar 

  • Davis, E. E., K. Becker, K. Wang, K. Obara, Y. Ito, and M. Kinoshita, A discrete episode of seismic and aseismic deformation of the Nankai trough subduction zone accretionary prism and incoming Philippine Sea plate, Earth Planet. Sci. Lett., 242, 73–84, 2006.

    Article  Google Scholar 

  • Elkhoury, J. E., E. Brodsky, and D. Agnew, Seismic waves increase permeability, Nature, 441, 1135–1138, 2006.

    Article  Google Scholar 

  • Gamage, K. and E. Screaton, Data report: Permeabilities of Nankai accretionary prism sediments, in Proc. ODP Sci. Results, edited by H. Mikada, G. Moore, A. Taira, K. Becker, J. Moore, and A. Klaus, 190/196, 1–22 (CD-ROM), 2005.

  • Hashimoto, M., K. Onoue, F. Ohya, Y. Hoso, K. Segawa, K. Sato, and Y. Fujita, Crustal deformation in Kii Peninsula associated with the SE off the Kii peninsula earthquake sequence of September 5, 2004 derived from dense GPS observations, Earth Planets Space, 57, 185–190, 2005.

    Article  Google Scholar 

  • Hayakawa, T., T. Furuma, and Y. Yamanaka, Simulation of strong ground motions caused by the 2004 off the Kii peninsula earthquakes, Earth Planets Space, 57, 191–196, 2005.

    Article  Google Scholar 

  • Hofton, M. A. and G. Foulger, Postrifting anelastic deformation around the spreading plate boundary, north Iceland 1. Modeling of the 1987–1992 deformation field using a viscoelastic Earth structure, J. Geophys. Res., 101, 25,403–25,421, 1996.

    Article  Google Scholar 

  • Imakiire, T., S. Ozawa, H. Yarai, T. Nishimura, and H. Suito, Crustal deformation by the Southeast-off Kii Peninsula earthquake, Bull. Geogr. Surv. Inst., 53, 51–56, 2006.

    Google Scholar 

  • Ito, Y., T. Matsumoto, H. Kimura, H. Matsubayashi, K. Obara, and S. Sekiguchi, Spatial distribution of centroid moment tensor solutions for the off Kii peninsula earthquakes, Earth Planets Space, 57, 351–356, 2005.

    Article  Google Scholar 

  • Jaeger, J. C. and N. G. W. Cook, Fundamentals of Rock Mechanics, Chapman and Hall Ltd., London, 1969.

  • Kastner, M., K. Becker, E. Davis, A. Fisher, H. Jannasch, E. Solomon, and G. Wheat, New insights into the hydrogeology of the oceanic crust through long-term monitoring, Oceanogr., 19, 46–57, 2006.

    Article  Google Scholar 

  • Mair, K. and C. Marone, Friction of simulated faulte gouge for a wide range of velocities and normal stresses, J. Geophys. Res., 104, 28,899–28,914, doi:10.1029/1999JB00279, 1999.

    Article  Google Scholar 

  • Matsumoto, H. and H. Mikada, Fault geometry of the 2004 off the Kii peninsula earthquake inferred from offshore pressure waveforms, Earth Planets Space, 57, 161–166, 2005.

    Article  Google Scholar 

  • Mikada, H., K. Becker, J. Moore, A. Klaus, and the shipboard scientific party, Proc. ODP Init. Repts., 196, CD-ROM, 2002.

  • Nakamula, S., M. Takeo, T. Yamada, M. Shinohara, and T. Kanazawa, Shallow low-frequency tremor in the accretionary prism along the Nankai Trough, Japan, Geophys. Res. Lett., 2008 (in review).

    Google Scholar 

  • Obara, K. and Y. Ito, Very low frequency earthquakes excited by the 2004 off the Kii peninsula earthquakes: A dynamic deformation process in the large accretionary prism, Earth Planets Space, 57, 321–326, 2005.

    Article  Google Scholar 

  • Okada, Y., Internal deformation due to shear and tensile faults in a half space, Bull. Seismol. Soc. Am., 82, 1,018–1,040, 1992.

    Google Scholar 

  • Okubo, M., Y. Asai, H. Aoki, and H. Ishii, The seismological and geodetical roles of strain seismogram suggested from the 2004 off the Kii peninsula earthquakes, Earth Planets Space, 57, 303–308, 2005.

    Article  Google Scholar 

  • Park, S. and J. Mori, The 2004 sequence of triggered earthquakes off the Kii Peninsula, Japan, Earth Planets Space, 57, 315–320, 2005.

    Article  Google Scholar 

  • Pollitz, F. F., Transient rheology of the upper mantle beneath central Alaska inferred from the crustal velocity field following the 2002 Denali earthquake, J. Geophys. Res., 110, B08407, doi:10.1029/2005JB003672, 2005.

  • Pollitz, F. F., C. Wicks, and W. Thatcher, Mantle flow beneath a continental strike-slip fault: Postseismic deformation after the 1999 Hector Mine earthquake, Science, 293, 1814–1818, 2001.

    Article  Google Scholar 

  • Rathbun, A. P., C. Marone, R. Alley, and S. Anandakrishnan, Laboratory study of the frictional rheology of sheared till, J. Geophys. Res., 113, F02020, doi:10.1029/2007JF000815, 2008.

  • Sakai, S., T. Yamada, M. Shinohara, H. Hagiwara, T. Kanazawa, K. Obana, S. Kodaira, and Y. Kaneda, Urgent aftershock observation of the 2004 off the Kii Peninsula earthquake using ocean bottom seismometers, Earth Planets Space, 57, 363–368, 2005.

    Article  Google Scholar 

  • Vidale, J. E. and H. Houston, The depth dependence of earthquake duration and implications for rupture mechanisms, Nature, 35, 45–47, 1993.

    Article  Google Scholar 

  • Wang, C.-Y., L. Cheng, C. Chin, and S. Yu, Coseismic hydrologic response of an alluvial fan to the 1999 Chi-Chi earthquake, Taiwan, Geology, 29, 831–834, 2001.

    Article  Google Scholar 

  • Wang, K., Applying fundamental principles and mathematical models to understand processes and estimate parameters, in Hydrogeology of the Oceanic Lithosphere, edited by E. E. Davis and H. Elderfield, 376–413, Cambridge University Press, Cambridge, 2004.

  • Wang, K. and Y. Hu, Accretionary prisms in subduction earthquake cycles: the theory of dynamic Coulomb wedge, J. Geophys. Res., 111, B06410, 2006.

    Google Scholar 

  • Wang, K. and J. He, Effects of frictional behaviour and geometry of subduction fault on coseismic seafloor deformation, Bull. Seismol. Soc. Am., 98, 571–579, 2008.

    Article  Google Scholar 

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Correspondence to Earl Davis.

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Davis, E., Becker, K., Wang, K. et al. Co-seismic and post-seismic pore-fluid pressure changes in the Philippine Sea plate and Nankai decollement in response to a seismogenic strain event off Kii Peninsula, Japan. Earth Planet Sp 61, 649–657 (2009). https://doi.org/10.1186/BF03353174

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