High Resolution Bottom Backscatter Measurements
Abstract
This docucment contains the slide presentation entitled High Resolution Bottom Backscatter Measurements given at the 107th meeting of the Acoustical Society of America on 8 May 1984 in Norfolk, VA. Acoustic bottom backscattering measurements and the corresponding geoacoustic properties of the ocean bottom are presented for an experiment conducted in the shallow water of the North Atlantic. The bottom scattering strength data, which were obtained with a high resolution (narrow beamwidth) parametric sonar, were measured as a function of frequency (5 to 20 kHz), grazing angle (4 deg to 11 deg), azimuthal angle (+ or -55 deg), and pulse length (0.4 to 10 ms). The supporting environmental measurements included box cores for determining the acoustic properties of the sediment and stereo photography for calculating the two- dimensional roughness spectrum of the sea floor. Analyses indicate that the measured reverberation was significantly influenced by the macrobenthos of the area. In particular, nonhomogeneous concentrations of highly reflective sand dollars resulted in bottom scattering strengths that exhibited both range and pulse width dependencies. No strong frequency or grazing angle dependence was observed. In addition, refractive conditions in the water column were found to markedly alter the time dispersive characteristics of bottom reverberation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 13, 1984
- Accession Number
- ADA163546
Entities
People
- R. K. Dullea
- W. I. Roderick
Organizations
- Naval Underwater Systems Center