Modelling Reverberation in the Northern Gulf of Mexico

Seafloor roughness is a major contributor to sound scattering and is thus an important component of seafloor reverberation models. Between April and May 2013 the TREX13 (Target and Reverberation Experiment 2013) sea trial was conducted in an area with a fine to medium grained sandy sea floor, just off the coast of Panama City, Florida. During this experiment numerous acoustic and oceanographic measurements were collected. Bathymetry and seafloor roughness spectra measurements collected during TREX have been analyzed and will be utilized as inputs for an acoustic scattering model. Results obtained from the scattering model will then be employed in a sea-bottom reverberation model, which will then be compared with reverberation measured during TREX13. Sub-bottom profiler data of seafloor acoustic reflectivity and FFCPT (Fee Fall Cone Penetration Testing) data collected during TREX will be used to help identify dominant scattering mechanisms. Based on results from the analysis of seafloor roughness spectra and bathymetry it is expected that the sediment will show uniform (isotropic) spectral characteristics. However, FFCPT and sub-bottom profiles indicate that discrete and volume scattering may also be observed.