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Earth, Planets and Space

, Volume 60, Issue 6, pp e9–e12 | Cite as

Weak interplate coupling beneath the subduction zone off Fukushima, NE Japan, inferred from GPS/acoustic seafloor geodetic observation

  • Yoshihiro Matsumoto
  • Tadashi Ishikawa
  • Masayuki Fujita
  • Mariko Sato
  • Hiroaki Saito
  • Masashi Mochizuki
  • Tetsuichiro Yabuki
  • Akira Asada
Open Access
E-Letter

Abstract

We have been carrying out GPS/acoustic seafloor geodetic observations at several reference points situated along the Japan Trench, a major plate boundary of subduction. A time series of horizontal coordinates of one of the seafloor reference points, located off Fukushima, obtained from seven campaign observations for the period 2002-2008, exhibits a linear trend with a scattering root mean square of about 3 cm. A linear fit to the time series gives an intraplate crustal movement velocity of 3.1 cm per year in a westerly direction, which is significantly smaller than that at the other seafloor reference point 120 km away along the trench axis. This result implies weak interplate coupling in this region.

Key words

GPS/acoustic seafloor geodetic observation back-slip Off Fukushima intraplate deformation 

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Copyright information

© The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences. 2008

Authors and Affiliations

  • Yoshihiro Matsumoto
    • 1
  • Tadashi Ishikawa
    • 1
  • Masayuki Fujita
    • 1
  • Mariko Sato
    • 1
  • Hiroaki Saito
    • 1
  • Masashi Mochizuki
    • 2
  • Tetsuichiro Yabuki
    • 1
  • Akira Asada
    • 2
  1. 1.Hydrographic and Oceanographic DepartmentJapan Coast GuardChuo-ku, TokyoJapan
  2. 2.Institute of Industrial Sciencethe University of TokyoMeguro, TokyoJapan

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