Accession Number : ADA311193

Title :   Three Dimensional, Finite-Difference Modeling to Determine the Dominant Backscatter from Seafloor Topography and Bottom Heterogeneity.

Descriptive Note : Final rept. 1 Dec 89-31 Aug 95,

Corporate Author : WOODS HOLE OCEANOGRAPHIC INSTITUTION MA

Personal Author(s) : Stephen, R. A.

PDF Url : ADA311193

Report Date : 23 OCT 1995

Pagination or Media Count : 7

Abstract : Specific objectives of the research were: (1) to add intrinsic attenuation to our Numerical Scattering Chamber (NSC) code, (2) to participate in ASA and NOARL sponsored benchmark studies for range dependent media, (3) to apply the NSC to scattering from canonical models to identify the physical mechanisms responsible for low angle back scatter, (4) to address the issue of stochastic versus deterministic methodologies for seafloor scattering, (5) to combine finite differences with ray theory in a hybrid scheme, (6) three dimensional finite difference modeling of facets, sediment cover, volume heterogeneities, Goff-Jordan seafloors, and ARSRP bright spot areas, and (7) to explain the relationship between deterministic features observed in the ARSRP '93 Acoustics Experiment and the geological structure of the seafloor. In addressing the last objective we chose to focus on the match filtered beam data for the wide band LFM 5sec chirps (200-255Hz). We studied initially the 1/2CZ data at Site A.

Descriptors :   *ACOUSTIC SCATTERING, *OCEAN BOTTOM TOPOGRAPHY, MATHEMATICAL MODELS, STOCHASTIC PROCESSES, OCEAN SURFACE, BACKSCATTERING, THREE DIMENSIONAL, FINITE DIFFERENCE THEORY, OCEANOGRAPHIC DATA, GEOACOUSTICS, MARINE GEOLOGY, HETEROGENEITY, ACOUSTIC ATTENUATION, RANGE FINDING, REVERBERATION, UNDERWATER ACOUSTICS, ACOUSTIC DATA, SEDIMENTS, SEISMOGRAPHS, GRAZING ANGLES.

Subject Categories : Physical and Dynamic Oceanography
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE