Gradient Representations in Seabed Geoacoustic Inversion by Bernstein Polynomials

Authors

  • Jorge E. Quijano School of Earth and Ocean Sciences University of Victoria Victoria BC Canada V8P 5C2
  • Stan E. Dosso School of Earth and Ocean Sciences University of Victoria Victoria BC Canada V8P 5C2
  • Charles W. Holland <p>Applied Research Laboratory, The Pennsylvania State University, State College PA, USA</p> <p> </p>
  • Jan Dettmer School of Earth and Ocean Sciences University of Victoria Victoria BC Canada V8P 5C2

Abstract

Geoacoustic properties of the upper-most transition layer of mud seabed sediments often change rapidly with depth as continuous gradients, rather than discontinuous layers. However, most geoacoustic inversion approaches are based on layered sediment models. This paper presents a seabed parameterization approach that represents continuous geoacoustic gradients as a sum of Bernstein polynomial basis functions weighted by unknown coefficients which are estimated by Bayesian inversion of seabed acoustic reflectivity data. The Bernstein representation is efficient/effective in representing a wide variety of gradients with a small number of coefficients, and has optimal numerical stability to perturbation of the coefficients in the nonlinear inversion scheme. The Bernstein parametrization in geoacoustic inversion is illustrated with simulated data and with experimental data from four mud sites on the Malta Plateau in the Strait of Sicily. The inversion results are in good agreement with sound speed and density estimates from co-located sediment cores, and serve to illustrate the ability of the Bernstein polynomial parameterization to represent steep and strongly-variable gradients.

Author Biographies

Jorge E. Quijano, School of Earth and Ocean Sciences University of Victoria Victoria BC Canada V8P 5C2

Research AssociateSchool of Earth and Ocean Sciences 

Stan E. Dosso, School of Earth and Ocean Sciences University of Victoria Victoria BC Canada V8P 5C2

Professor and DirectorSchool of Earth and Ocean Sciences 

Charles W. Holland, <p>Applied Research Laboratory, The Pennsylvania State University, State College PA, USA</p> <p> </p>

Senior Scientist ProfessorGraduate Program of Acoustics

Jan Dettmer, School of Earth and Ocean Sciences University of Victoria Victoria BC Canada V8P 5C2

Adjunct ProfessorSchool of Earth and Ocean Sciences

Additional Files

Published

2016-08-24

How to Cite

1.
Quijano JE, Dosso SE, Holland CW, Dettmer J. Gradient Representations in Seabed Geoacoustic Inversion by Bernstein Polynomials. Canadian Acoustics [Internet]. 2016 Aug. 24 [cited 2024 Mar. 29];44(3). Available from: https://jcaa.caa-aca.ca/index.php/jcaa/article/view/2907

Issue

Section

Proceedings of the Acoustics Week in Canada