f Single scattering representation of elastic wave reflection and transmission

An understanding of elastic wave scattering by point diffractors is of prime importance for the detection of small spatial or temporal changes in subsurface properties. We have developed a forward modeling tool to calculate the first-order diffraction effects produced by small-scale inhomogeneities embedded in a stratified elastic medium. This computational method allows us to study the threedimensional radiation of spatial distributions of point scatterers in depth-dependent elastic media, such as undulating reflectors or inclusions of complex shape. In order to test this model and assess its limitations, we consider here the simple case of reflected and transmitted waves at plane interfaces by representing these interfaces with regular arrangements of point diffractors. Specific points addressed in this paper include the size and discretization of the contributive zone (used for accurately representing the reflection and transmission effects), the reliability of the single scattering theory at oblique angles of incidence, and its ability to represent strong model perturbations.