Abstract:

A null-field T-matrix formalism developed for plane-wave scattering from a fluid-loaded elastic spherical shell in proximity to a rough fluid elastic interface [J. Acoust. Soc. Am. 101, 767--788 (1997)] is extended to include scattering from sound-hard and -soft spherical targets and a sound-hard finite cylinder with hemispherical end caps and, for a planar interface, sound-hard, sound-soft, and fluid-saturated poroelastic sediments. A variety of numerical results are obtained that demonstrate some of the effects of target and sediment parameters on target--boundary acoustic coupling and target strength. Then, for small amplitude surface roughness, a perturbation formalism is used to indicate some of the effects of interface roughness.