© 2003 by Oxford University Press
Generalized-Screen Approximation and Algorithm for the Scattering of Elastic Waves
( 1 Center for Wave Phenomena, Colorado School of Mines, Golden, CO 80401, USA )
We describe the propagation and scattering of elastic waves in heterogeneous media. Decomposing the elastic wavefield into up- and down-going constituents allows the introduction of the one-way wave equations and propagators. Such propagators account for transverse scattering and mode coupling. The generalized-screen expansion of the symbol of the one-way wave equation in medium contrast and medium smoothness induces an approximation of the propagator with an associated computational complexity of the one of the phase screen approximation. The generalized-screen expansion extends the phase-screen approach. It allows for larger medium fluctuations and wider-angle propagation. We illustrate the accuracy of the generalized screen with numerical examples.
Received 7 May 2001. Revised 10 November 2001.