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Experimental and Theoretical Studies of Seismic Interface Waves in Coastal Waters

  • Dieter Rauch
Part of the NATO Conference Series book series (NATOCS, volume 5)

Abstract

A digital three-component ocean-bottom seismometer has been developed at SACLANTCEN to study extremely-low-frequency sound propagation in coastal waters (e.g. below the cut-off of the shallow-water duct). It has been used successfully in conjunction with a variable depth hydrophone during several sea trials off the Italian coast. By exploding small charges (45 to 900 g TNT) at various distances (up to 5 km) it has been demonstrated that the infrasonic energy is mainly transmitted via a seismic interface wave. In general this propagation mode may be termed a modified Scholte wave as it is guided by the acoustically most significant interface between water column (including liquid-type sediments) and solid basement. On a sedimentary sea floor very pronounced wavelets have been observed, at frequencies in the 1.5 to 6 Hz band, group-velocities in the 250 to 70 m/s range, and hodographs in the vertical radial plane. Together with this experimental program theoretical studies have been made using a seismic Fast-Field-Program, which has proved to be a very powerful tool to model infrasonic phenomena in shallow-water environments.

Keywords

Coastal Water Sand Layer Stoneley Wave Acoustic Propagation Italian Coast 
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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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • Dieter Rauch
    • 1
  1. 1.SACLANT ASW Research CentreLa SpeziaItaly

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