2025_programme: Individual and joint inversion of modal amplitude and modal arrival-time data for the estimation of seabed geoacoustic models

• Day: June 16, Monday
    Location / Time: B. ERATO at 14:50-15:10
• Last minutes changes: -
• Session: 07. Inverse Problems in Acoustical Oceanography
  Organiser(s): Julien Bonnel, Stan Dosso
  Chairperson(s): Julien Bonnel, Stan Dosso
• Lecture: Individual and joint inversion of modal amplitude and modal arrival-time data for the estimation of seabed geoacoustic models
  Paper ID: 2164
  Author(s): Yong Min Jiang, Stan Dosso, Julien Bonnel
  Presenter: Yong Min Jiang
  Abstract: Modal-dispersion data, i.e. modal arrival times as a function of frequency, have been inverted to estimate sound speeds and densities for layered seabed models by a number of researchers, but provide no information on seabed attenuation. According to normal-mode theory, modal-amplitude data as a function of frequency contain information about attenuation, in addition to sound speed and density, and can be inverted to estimate all of these properties. However, measured modal-amplitude data depend on the source spectrum, which is commonly unknown in many underwater-acoustic applications. This paper investigates the feasibility of using modal amplitude data for seabed geoacoustic inversion. Source spectral parameters are treated as unknowns in the inversion, formulated implicitly within the likelihood function of a trans-dimensional Bayesian inversion. Modal-dispersion and modal-amplitude data sets are inverted individually and considered together in joint inversion. Inversions are applied to simulated data with different levels of additive noise, to evaluate the robustness of the inversion. Inversion results for modal data collected on the New England Mud Patch are also considered. (Work supported by the Office of Naval Research.)
• Corresponding author: Dr Yong Min Jiang
  Affiliation: School of Earth and Ocean Sciences, University of Victoria
  Country: Canada