ASA 126th Meeting Denver 1993 October 4-8

2aUW8. Bottom backscattering strengths derived from shallow-water reverberation measurements.

Dale D. Ellis John R. Preston

SACLANT Undersea Res. Ctr., Viale San Bartolomeo 400, 19138 La Spezia, Italy

A normal-mode model for calculating surface and bottom reverberation in shallow water has been developed, and found to give good agreement with single-hydrophone data for a fairly flat-bottomed area [D. D. Ellis, SACLANTCEN Report SR-196 (September 1992)]. The model has been extended to include beam patterns and has been compared with broadband data received on a horizontal line array. The model-data agreement is again generally quite good. When the model-data differences as a function of beam angle and time are overlaid on a map of the area, the differences are seen to be primarily due to changes in the bottom bathymetry. This can be used to extract a measure of the bottom backscattering strength versus location.