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Volume 54 Supplement 11

Special Issue: Slip and Flow Processes in and below the Seismogenic Region

P-T conditions of cataclastic deformation associated with underplating: An example from the Cretaceous Shimanto complex, Kii Peninsula, SW Japan


P-T conditions of cataclastic deformation associated with underplating in subduction zone are estimated from fluid inclusions within the post-mélange veins in the Cretaceous Shimanto Belt, Kii Peninsula, SW Japan. Both cataclasite and post-mélange veins cut the mélange fabric and are distributed along the thrusts in duplex structure. The homogenization temperatures range from 200 (±10)°C to 270 (±42)°C corresponding to entrapment pressures over a wide range from 145 (±5) MPa to 304 (−20) MPa. Our results have important implications in evaluating the relationship between underplating processes by duplexing and coseismic deformation in accretionary complexes.


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Correspondence to Yoshitaka Hashimoto.

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Hashimoto, Y., Enjoji, M., Sakaguchi, A. et al. P-T conditions of cataclastic deformation associated with underplating: An example from the Cretaceous Shimanto complex, Kii Peninsula, SW Japan. Earth Planet Sp 54, 1133–1138 (2002).

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  • Fluid Inclusion
  • Subduction Zone
  • Geothermal Gradient
  • Accretionary Prism
  • Lithostatic Pressure