Wavenumber analysis of interface wave characteristics using elastic parabolic equation solutions

Interface waves that travel along the ocean bottom are known as Scholte waves and can contribute to the deep ocean acoustic field, even at depths below the ray-theoretical turning point. Scholte waves spread by the inverse of the square root of range and propagate greater distances along the ocean floor than ocean acoustic energy. Elastic parabolic equation solutions are effective for analysis of Scholte wave behavior with respect to environmental parameters since these waves represent interactions between dilatational and rotational elastic waves resulting from elastic boundary conditions. Generation of interface waves by water column and buried seismic sources will be demonstrated. Hankel transforms of calculated acoustic pressure will be used to evaluate impact of elastic parameters on interface wave amplitudes and ducting effects in elastic sediment layers. The effect of large-scale bathymetry on interface wave propagation will also be investigated. [Work supported by ONR.]