Improving the parabolic equation solution for problems involving poro-elastic media

Parabolic equation solutions for elastic media have undergone several modifications recently that increase their capabilities and accuracy. These include formulation in different dependent variables, approaches for handling range dependence such as coordinate rotations and single scattering, and treatment of media anisotropy. These advances are being extended to problems with heterogeneous and range-dependent poro-elastic media, which provide useful models of some shallow-water sediments. Other parabolic equation solutions for poro-elastic media [Collins et al., J. Acoust. Soc. Am. 98, 1645–1656 (1995)] are prior to recent progress. Vertical dependence is treated by applying heterogeneous depth operators from the equation of motion. Horizontal dependence is treated by incorporating single-scattering approaches. [Work supported by the ONR.]