Numerical solutions to the elastic wave equations for plane monochromatic P-waves scattered in models with irregular boundaries can explain the magnitude of the variations in the amplitude and arrival time of short-period teleseismic recordings observed at receivers located within a few wavelengths of each other. Solutions are obtained using finite difference techniques on a perturbation about a plane wave solution of the elastic wave equations for isotropic 2-dimensionally inhomogeneous media. Three models of structure along a discontinuity are considered: A horst-like 5 kilometer upwelling of the lower medium into the upper over 10 kilometers along the discontinuity; a graben-like depression into the lower medium of the same size; and, a faultlike offset step in the discontinuity of 5 kilometers over 5 kilometers. For each model solutions are calculated for normal and 10° off normal incidence. Impedance contrasts applicable to the lower crust are used.

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