Abstract:
In July 1993 SACLANTCEN participated in an experiment for the acoustic reverberation special research program (ARSRP). The primary objective was to take high-resolution measurements to determine the detailed physical processes dominating the low-frequency scattering from rough topographic features and from deep sediment pond areas. A very detailed set of monostatic and bistatic scattering experiments were conducted (using low frequencies from 200--375 Hz) just west of the Mid-Atlantic Ridge near 26(degrees) N and 47(degrees) W. This paper presents towed array data recorded by SACLANT Centre's R/V ALLIANCE for comparison with FEPE two way parabolic equation model estimates of selected ARSRP geometries. The receivers were horizontal arrays of 128 elements spaced at 0.5, 1, and 2 m. Source/receiver depths were (approximately equal to)130 and 450 m, respectively. Inferences for monostatic bottom scattering mechanisms are discussed based on the FEPE model from Collins to interpret the data. The modeling work isolates different scattering mechanisms to assess their relative contributions to the overall reverberation levels observed in the data.