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Seafloor Acoustic Ranging and the Effect of Temperature Variation

  • Hiromi Fujimoto
  • Toshihiko Kanazawa
  • Hideyuki Murakami
Part of the International Association of Geodesy Symposia book series (IAG SYMPOSIA, volume 117)

Abstract

Although acoustic ranging of a resolution of 1 cm at a baseline length of several kilometers is now an attainable target, correction for temperature variations remains to be a serious problem. A seafloor experiment was carried out to estimate how accurately the effect of temperature variation on the sound velocity can be corrected from the temperature data observed at both ends of the baseline. The water temperature on the shallow (about 1400 m) seafloor of Sagami Bay, Central Japan, showed tidal variation of about 0.2 °C, which corresponds to the acoustic range of about 1 m at the baseline length of 1.5 km. Although temperature variations at both ends were considerably different from each other, the effect on the acoustic ranging could be corrected with r.m.s. residuals of 7 cm. The residuals are caused by short-term fluctuations, and the correction can be better for longterm variations. If temperature on the deep seafloor is more stable by one order, measurement of 1 cm at a baseline length of several kilometers can be a reasonable target.

Keywords

Sound Velocity Acoustic Signal Kuroshio Current Baseline Length Tidal Variation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Fujimoto, H., T. Kanazawa, and H. Murakami, Experiment on precise seafloor acoustic ranging - A promising results of observation -, J. Seismol. Soc. Japan, 48, 289 - 292, 1995.Google Scholar
  2. Spiess, F. N., D. E. Boegeman, C. D. Lowenstein, and M. O. McIntyre, Precise sea floor positioning - a progress report, Proc. INSMAP 90, Marine Technology Society, Washington, D. C., USA, 51 - 60, 1991.Google Scholar
  3. Spiess, F. N., G. H. Purcell, Jr., L. E. Young, and H. Dragert, Determination of sea floor displacements using precision transponders and GPS, Proc. INSMAP 94, Marine Technology Society, Washington, D. C., USA, 125 - 131, 1994.Google Scholar
  4. Yabuki, T., Y. Nagaya, A. Asada, F. Ono, and K. Tajiri, Proc. INSMAP 94, Marine Technology Society, Washington, D. C., USA, 493 - 498, 1994Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Hiromi Fujimoto
    • 1
  • Toshihiko Kanazawa
    • 2
  • Hideyuki Murakami
    • 3
  1. 1.Ocean Research InstituteThe University of TokyoNakano-ku, Tokyo 164Japan
  2. 2.Earthquake Research InstituteThe University of TokyoBunkyo-ku, Tokyo 113Japan
  3. 3.Kaiyo Denshi, Inc.Kawagoe 350Japan

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