Scattering of Scholte Waves by Partially Buried Inclusions

Scholte waves are interface-guided elastic waves propagating along fluid–solid boundaries, characterized by strong near-interface localization and high sensitivity to subsurface heterogeneities. These properties make them promising candidates for the detection of partially buried objects in underwater environments. In this work, the scattering of Scholte waves by a partially buried elastic inclusion is investigated using a fully coupled acoustoelastic finite-element model. The formulation captures wave generation, mode conversion, and energy exchange across the fluid–solid interface. The results reveal that the interaction between the incident Scholte wave and the buried object gives rise to two distinct scattering mechanisms. One wave component remains interface-guided and propagates along the boundary, contributing to the backscattered field, while a second component is localized along the object surface and propagates as a circumferential wave, leading to strong near-field energy confinement. The relative contribution of these mechanisms is shown to depend strongly on the burial depth, which governs the coupling between the interface-guided wavefield and the inclusion. Applicability of delay-and-sum methods of image reconstruction to the detection of partially buried objects based on the backscattered response is finally explored.