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A note on attenuation and dispersion in marine sediments
(NATO. SACLANTCEN, 1989/04)
From the more recent investigations reported ill the literature,
An acoustic, high resolution, sediment profiler
(NATO. SACLANTCEN, 1966/11)
An acoustic sediment profiler is described that utilizes short 50 kHz pulses to achieve a high range resolution. In trials in shallow water, penetration depths of about 9 m and resolution of about 25 cm were obtained. ...
Subcritical penetration of narrow Gaussian beams into sediments
(NATO. SACLANTCEN, 1988/03)
Complete wave-theory solutions have been obtained numerically for both the reflected and the transmitted fields associated with a narrow Gaussian beam incident on a water-sediment interface near the critical grazing angle. ...
Acoustic properties of the sea floor: a review
(NATO. SACLANTCEN, 1975/10)
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. ...
Bottom-interacting ocean acoustics: proceedings of a conference held at SACLANTCEN on 9-13 June 1980
(NATO. SACLANTCEN, 1980/07)
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 ...
Ocean-bottom reflectivity (a point of view)
(NATO. SACLANTCEN, 1975/10)
The analysis procedures for extracting bottom loss values from pulsed acoustic signals that have interacted with the ocean bottom do not inherently consider sub-bottom refraction and reflection of sound, which are important ...
Principles and methods of core analysis at the SACLANT ASW Research Centre
(NATO. SACLANTCEN, 1967/08)
The methods and accuracy of measuring core parameters at the SACLANTCEN are described. Those for measuring sound velocity and electrical resistivity are explained in detail.