COMMON SHOT GATHER MODELING AND INVERSION
, by Allan Snyder
The monochromatic 45 degree equation and phase shift method are used to generate and invert common shot
gathers (CSG's). The modeling algorithm uses the basic principle U = cD, where U is the upgoing wave, c is
the reflection coefficient and D is the downgoing wave. The basic idea of the inversion preocess is to find
those points in space where the up- and downgoing waves are time-coincident, which is where reflectors exist.
This method has an advantage over the standard industrial migration procedure in that it handles lateral
velocity variation and steeply dipping beds, which invalidate the standard assumption in industry that a
zero-offset section is identical to a CDP stack.
STANFORD