Remote sensing of seabed compressional wave attenuation from acoustic cw propagation experiments combined with the bottom shear modulus profiler (BSMP) database

Abstract

As a result of recent ONR shallow water ARI, an accurate database of the compressional wave velocity, the shear wave velocity, and the density of the sediment for the continental shelves of Northeastern U.S. is available (Yamamoto and Trevorrow, in this conference). It has been shown that the model structures of acoustic waves propagating in these shallow waters are very accurately modeled using the BSMP database as compared with the cw propagation experiments [J. Acoust. Soc. Am. Suppl. 1 88, S106 (1990)]. In this paper, it is shown that the compressional wave attenuation within the seabed can be accurately determined from the wave-number energy spectra of cw propagation data from range-independent environments. The seabed geoacoustic data so obtained are then used in the modeling of acoustic cw propagation in range-dependent cases using Fred Tappert's PE code and compared with Bill Carey's experiments. Excellent agreements between model calculations and experiments are obtained, indicating the accuracy and stability of the combined BSMP-cw experiments for determination of seabed compressional wave attenuation in shallow water. [Work sponsored by ONR.]