2023_programme: Geoacoustic Inversion of Matched Field and Modal Dispersion Data on the New England Mud Patch

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  • Session: 04. Inverse Problems in Acoustical Oceanography
    Organiser(s): Julien Bonnel and Stan Dosso
  • Lecture: Geoacoustic Inversion of Matched Field and Modal Dispersion Data on the New England Mud Patch
    Paper ID: 1991
    Author(s): Dosso Stan, Bonnel Julien
    Presenter: Dosso Stan
    Abstract: This paper compares the information content to resolve seabed geoacoustic structure from acoustic recordings of an impulsive sound source processed in terms of either modal dispersion data (mode arrival times as a function of frequency) or broadband matched-field (MF) data (complex acoustic-field variations across a vertical sensor array). In principle, MF data have greater information content, as they involve full-field (amplitude and phase) information over a vertical aperture. However, MF inversion requires the source depth and complex source spectrum to be estimated as part of the inverse problem, reducing the information content for seabed estimation, and can be sensitive to knowledge of array tilt and/or sensor positions. Further, MF inversion provides sensitivity to seabed acoustic attenuation, which absent in dispersion data. A rigorous comparison of geoacoustic information content for these two acoustic data sets is facilitated by the use of trans-dimensional (trans-D) inversion, which includes an automated, quantitative approach to model selection as an intrinsic component of the algorithm. Here, trans-D inversion is employed to sample probabilistically over the number of seabed layers included in the geoacoustic model, as well as over the order (zeroth or first) of an autoregressive error model. This study is illustrated on experimental modal dispersion and MF data, with the two data sets derived from the same acoustic waveform recordings collected as part of the 2017 Seabed Characterization Experiment on the New England Mud Patch. [Work supported by the Office of Naval Research.]
  • Corresponding author: Prof Stan Dosso
    Affiliation: University of Victoria
    Country: Canada
    e-mail:

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