REPRESENTATION OF SEISMIC SOURCES IN THE ONE-WAY WAVE-EQUATIONS

One-way extrapolation of downgoing and upgoing acoustic waves plays an essential role in the current practice of seismic migration. Generally, one way wave equations are derived for the source-free situation. Sources of error in the technique are discussed. Here, one-way wave equations are derived that include a source term. From these equations it becomes clear how seismic sources can be properly represented in one-way extrapolation schemes. An important application is pre-stack migration. Particularly when one tries to image the angle-dependent properties of subsurface reflectors, a proper treatment of source directivity is essential. This is also illustrated. -from Author