Investigating seabed biogeoacoustic variability through measurements and modeling

Abstract

Acoustic remote sensing methods provide the capability to rapidly interrogate the seabed over wide swaths, hence better fundamentalunderstanding of benthic processes and how they couple to seabed acoustics has significant importance for naval, economic, and climate applications. Bioturbation and biogeochemical processes can influence sediment physical properties, such as porosity, grain size, permeability, and viscoelasticity. The effects of these processes contribute to spatiotemporal variability in seabed geoacousticproperties, including sediment sound speed and attenuation, bulk and interface shear wave propagation, and seabed acoustic scattering, all of which can have impacts on sonar-based sensing of the seabed. The scientific goals of this project are: (1) to better understand the effects of benthic physical, biogeochemical, and biological processes on seabed geoacoustic properties, (2) to quantify deviation of measured acoustic properties from sediment acoustics model predictions, which take seabed physical properties as inputsand do not include effects of benthic biology or chemistry, and (3) to ultimately develop and test new and improved comprehensive predictive seabed models to will be useful in mapping seabed acoustic properties to physical properties such as carbon content or load-bearing strength. To accomplish these goals, we will leverage in situ direct and remote sediment acoustic measurements, core samples, and other observations from real ocean bottom sediments provided by related research efforts to investigate relationships between various these benthic processes and sediment properties near the seabed surface. Furthermore, we propose to investigate new ways to apply existing seabed models to describe the data, and when existing models are not sufficient, we will seek to develop new predictive models.Approved for Public Release

Document Details

Document Type
DoD Grant Award
Publication Date
Mar 12, 2025
Source ID
N000142512176

Entities

People

  • Kevin M. Lee

Organizations

  • Office of Naval Research
  • United States Navy
  • University of Texas at Austin

Tags

Fields of Study

  • Environmental science

Readers

  • Acoustical Oceanography.
  • Marine Ecotoxicology