2023_programme: A generalized-ray modeling approach to low-frequency sound propagation in a shallow water wedge over an elastic seabed

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  • Session: 03. Comprehensive Nuclear-Test-Ban Treaty Monitoring and its Civil and Scientific Applications
    Organiser(s): Georgios Haralabus, Mario Zampolli and Peter Nielsen
  • Lecture: A generalized-ray modeling approach to low-frequency sound propagation in a shallow water wedge over an elastic seabed [invited]
    Paper ID: 1900
    Author(s): Borejko Piotr
    Presenter: Borejko Piotr
    Abstract: In shallow-water environments long-range propagation proceeds by repeated reflections from the surface and the bottom of the channel, as is the case for an underwater sound of a wide spectral range, whose very low frequencies may propagate over large distances, without significant losses. \n\nIn this paper, a 3-D benchmark model of the fluid wedge over an elastic bottom is applied to explain low-frequency long-range propagation in shallow water overlaying a sloping elastic-type seabed, such as a marine sediment possessing enough rigidity (elasticity in shear) allowing hydroacoustic-to-seismic conversion at a water-sediment interface. \n\nWith a point source in the wedge, a generalized-ray approach is applied to the model to evaluate a complete acoustic signal recorded by a remote receiver, comprised of contributions from all of the wave motions typical for the model [not only from the source signal and the regularly reflected waves but also from the refracted (lateral) waves and the pseudo-Rayleigh and Scholte interface waves] received in order of their arrivals at a large distance from the source. \n\nWhen the source emits signals of a low-frequency content, the contribution from the Scholte waves becomes dominant at large distances. Therefore, low-frequency long-range propagation in a shallow water wedge (coastal wedge) over an elastic seabed may indeed be governed by the Scholte waves. \n\nThis work may offer useful insights into the global scale modeling efforts at CTBTO.
  • Corresponding author: Dr Piotr Borejko
    Affiliation: TU Wien
    Country: Austria
    e-mail:

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