Transition from collision to subduction and its relation to slab seismicity and plate coupling

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• 作者：Ryuta Arai ; Takaya Iwasaki
• 关键词：Nankai trough ; Izu collision zone ; Philippine Sea plate ; Plate coupling ; Frictional property ; Wide ; angle reflections
• 刊名：Earth, Planets and Space
• 出版年：2015
• 出版时间：December 2015
• 年：2015
• 卷：67
• 期：1
• 全文大小：3984KB
• 参考文献：Aizawa K, Yoshimura R, Oshiman N (2004) Splitting of the Philippine Sea Plate and a magma chamber beneath Mt. Fuji Geophys Res Lett 31:L09603. doi:10.1029/2004GL019477
  Ando M (1975) Possibility of a major earthquake in the Tokai district, Japan and its pre-estimated seismotectonic effects. Tectonophysics 25:69-5CrossRef
  Aoike K (1999) Tectonic evolution of the Izu collision zone. Res Rep Kanagawa prefect Mus Nat His 9:111-51
  Arai R, Iwasaki T (2014) Crustal structure in the northwestern part of the Izu collision zone in central Japan. Earth Planets Space 66:21CrossRef
  Arai R, Iwasaki T, Sato H, Abe S, Hirata N (2009) Collision and subduction structure of the Izu-Bonin arc, central Japan, revealed by refraction/wide-angle reflection analysis. Tectonophysics 475:438-53CrossRef
  Arai R, Iwasaki T, Sato H, Abe S, Hirata N (2013) Crustal structure of the Izu collision zone in central Japan from seismic refraction data. J Geophys Res Solid Earth 118:6258-268. doi:10.1002/2013JB010532CrossRef
  Arai R, Iwasaki T, Sato H, Abe S, Hirata N (2014) Contrasting subduction structures within the Philippine Sea plate: Hydrous oceanic crust and anhydrous volcanic arc crust. Geochem Geophys Geosyst 15:1977-990. doi:10.1002/2014GC005321CrossRef
  ?erveny V, P?en?ík I (1983) Program package SEIS83. Charles University, Prague
  Fujie G, Miura S, Kodaira S, Kaneda Y, Shinohara M, Mochizuki K, Kanazawa T, Murai Y, Hino R, Sato T, Uehira K (2013) Along-trench structural variation and seismic coupling in the northern Japan subduction zone. Earth Planets Space 65:75-3CrossRef
  Iidaka T, Takeda T, Kurashimo E, Kawamura T, Kaneda Y, Iwasaki T (2004) Configuration of subducting Philippine Sea plate and crustal structure in the central Japan region. Tectonophysics 388:7-0CrossRef
  Iwasaki T (1988) Ray-tracing program for study of velocity structure by ocean bottom seismographic profiling. J Seismol Soc Jpn 41:263-66
  Kato A, Iidaka T, Ikuta R, Yoshida Y, Katsumata K, Iwasaki T, Sakai S, Thurber C, Tsumura N, Yamaoka K, Watanabe T, Kunitomo T, Yamazaki F, Okubo M, Suzuki S, Hirata N (2010) Variations of fluid pressure within the subducting oceanic crust and slow earthquakes. Geophys Res Lett 37:L14310. doi:10.1029/2010GL043723
  Katsumata A (2010) Depth of the Moho discontinuity beneath the Japanese islands estimated by traveltime analysis. J Geophys Res 115:B04303. doi:10.1029/2008JB005864
  Kodaira S, Kurashimo E, Park JO, Takahashi N, Nakanishi A, Miura S, Iwasaki T, Hirata N, Ito K, Kaneda Y (2002) Structural factors controlling the rupture process of a megathrust earthquake at the Nankai trough seismogenic zone. Geophys J Int 149:815-35CrossRef
  Kodaira S, Iidaka T, Kato A, Park J, Iwasaki T, Kaneda Y (2004) High pore fluid pressure may cause silent slip in the Nankai trough. Science 304:1295-298CrossRef
  Kodaira S, Sato T, Takahashi N, Ito A, Tamura Y, Tatsumi Y, Kaneda Y (2007) Seismological evidence for variable growth of crust along the Izu intraoceanic arc. J Geophys Res 112:B05104. doi:10.1029/2006JB004593
  Kodaira S, Sato T, Takahashi N, Yamashita M, No T, Kaneda Y (2008) Seismic imaging of a possible paleoarc in the Izu-Bonin intraoceanic arc and its implications for arc evolution processes. Geochem Geophys Geosyst 9:Q10X01. doi:10.1029/2008GC002073CrossRef
  Kurashimo E, Tokunaga M, Hirata N, Iwasaki T, Kodaira S, Kaneda Y, Ito K, Nishida R, Kimura S, Ikawa T (2002) Geometry of the subducting Philippine Sea Plate and the crustal and upper mantle structure beneath eastern Shikoku Island revealed by seismic refraction/wide-angle reflection profiling. Zisin 54:489-05
  Matsubara M, Obara K, Kasahara K (2008) Three-dimensional P- and S-wave velocity structures beneath the Japan Islands obtained by high-density seismic stations by seismic tomography. Tectonophysics 454:86-03CrossRef
  Mochizuki K, Nakamura M, Kasahara J, Hino R, Nishino M, Kuwano A, Nakamura Y, Yamada T, Shinohara M, Sato T, Moghaddam PP, Kanazawa T (2005) Intense PP reflection beneath the aseismic forearc slope of the Japan Trench subduction zone and its implication of aseismic slip subduction. J Geophys Res 110:B01302. doi:10.1029/2003JB002892
  Nakajima J, Hirose F, Hasegawa A (2009) Seismotectonics beneath the Tokyo metropolitan area, Japan: Effect of slab-slab contact and overlap on seismicity. J Geophys Res 114:B08309. doi:10.1029/2008JB006101
  Nakanishi A, Shiobara H, Hino R, Kodaira S, Kanazawa T, Shimamura H (1998) Detailed subduction structure across the eastern Nankai Trough obtained from ocean bottom seismograph profiles. J Geophys Res 103:27151-7168CrossRef
  Nakanishi A, Smith AJ, Miura S, Tsuru T, Kodaira S, Obana K, Takahashi N, Cummins PR, Kaneda Y (2004) Structural factors controlling the coseismic rupture zone of the 1973 Nemuro-Oki earthquake, the southern Kuril Trench seismogenic zone. J Geophys Res 109:B05305. doi:10.1029/2003JB002574
  Nakanishi A, Kodaira S, Miura S, Ito A, S
• 作者单位：Ryuta Arai (1)
  Takaya Iwasaki (2)
  
  1. Japan Agency for Marine-Earth Science and Technology, 3173-25 Showa-machi Kanazawa-ku, Yokohama, Kanagawa, 236-0001, Japan
  2. Earthquake Research Institute, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-0032, Japan
  
• 刊物类别：Earth Sciences, general; Geology; Geophysics/Geodesy;
• 刊物主题：Earth Sciences, general; Geology; Geophysics/Geodesy;
• 出版者：Springer Berlin Heidelberg
• ISSN：1880-5981

文摘

The Philippine Sea plate exhibits an along-trench variation in structure, from an eastern volcanic arc to a typical oceanic crust in the west. The regional difference of intra-slab seismicity implies that this transition occurs around the Itoigawa-Shizuoka Tectonic Line (ISTL). However, the nature of the subducting slab in this region has not been studied in detail. Here, we investigate the structure of the Philippine Sea plate subducting beneath the ISTL. Using active source data, we found reflective portions at depths of 14-8 km. An amplitude evaluation for the reflection phases showed that the reflective zone has a P wave velocity as low as 3.0 km/s. Together with its slightly northwestward-dipping geometry, we interpreted that the low-velocity zone is at the plate boundary and can be attributed to high water content supplied by the slab. This feature is in great contrast to the collision zone further east, where the slab top is less reflective and the dehydration process is inactive. This structural difference also correlates well with the regional distribution of slab seismicity. The reflective zones we found are likely located at the down-dip end of the locked zone, where high slip deficit rates are currently observed. This may suggest that changing fluid pressures and the resulting frictional properties in the down-dip direction control the transition from a coseismic rupture zone to a deeper aseismic zone. Keywords Nankai trough Izu collision zone Philippine Sea plate Plate coupling Frictional property Wide-angle reflections