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Bottom bistatic scattering: experimental results and model comparison for a carbonate sediment
(NATO. SACLANTCEN, 1997)
Bistatic scattering measurements were carried out under the Coastal Benthic Boundary Layer (CBBL) program. The results presented here are for a carbonate sand-silt-clay, and the data were collected in Februar) 1995 near ...
Sedimentological acoustics: an attempt to reduce the gap between acoustical modeling and sedimentoloogical survey
(NATO. SACLANTCEN, 1997)
A major task in shallow water acoustics is to provide pertinent geoacoustical data. The purpose of the work is to evaluate the state of the art in this field, connecting in situ sedimentological measurement and acoustical ...
Modeling range-dependent, high-frequency, shallow-water torpedo reverberation data
(NATO. SACLANTCEN, 1997)
The high-frequency, forward bottom losses predicted by a lossy Rayleigh and a Biot poroelastic sediment model are substantially different. These differences will accumulate and become measurable in multiple bottom bounce ...
Uniqueness problems in extracting environmental parameters from high-frequency shallow-water reverberation measurements
(NATO. SACLANTCEN, 1997)
Inversion techniques that extract environmental parameters from measured reverberation often lead to mathematical problems that are not well-posed. Two examples illustrate this possibility. The first hows how a model can ...
Vertical porosity and velocity fluctuations in shallow-water surficial sediments and their use in modeling volume scattering
(NATO. SACLANTCEN, 1997)
Variability in sediment porosity and velocity creates volume scattering which is a parameter used in high-frequency scattering models. High-resolution vertical profiles of sediment porosity and compresstonal wave velocity ...
Attenuation of shear waves in near-surface sediments
(NATO. SACLANTCEN, 1997)
In situ measurement of compressional and shear speed and compressional attenuation in near-surface marine sediments is a well-developed technology but techniques required to measure shear attenuation have lagged behind. ...
Spatial variability of surficial shallow water sediment geoacoustic properties
(NATO. SACLANTCEN, 1986/06)
Variability of surficial sediment geoacoustic properties was determined from cores collected at eight shallow-water continental shelf regions in the U.S., Italy and Australia. Highly porous muds found in low energy ...
An experimental investigation of the contribution of sediment volume scattering to acoustic backscatter measured in the shallow waters of the Florida Strait
(NATO. SACLANTCEN, 1997)
Experiments were conducted in the Florida Strait region of the United States in July 1995 for the purpose of investigating the contribution of sediment volume scattering to measured backscatter levels at frequencies between ...
Small scale volumetric inhomogeneities of shallow water sediments: measurements and discussion
(NATO. SACLANTCEN, 1997)
There is a consensus that high-frequency acoustic scattering by the ocean bottom is partly due to sediment volumetric inhomogeneities, r e., random fluctuations in sediment sound speed and density. Understanding the spatial ...
A solution of of the wave sound equation in shallow water for real speed profiles and solid bottom under sediment
(NATO. SACLANTCEN, 1975/10)
The wave equation has been solved by using normal mode theory. The medium is assumed to be horizontally stratified. A closed form solution has been found in the case of GANS - PEDERSEN types of density and sound-speed ...