PERM

Source-receiver two-way wave extrapolation for prestack exploding-reflector modeling and migration

A new innovative approach to time extrapolate the wave field in the source and receiver domain, with capabilities in modeling and imaging the exploration seismic experiment in a direct way. We use a new prestack wave formulation for nonphysical waves to simulate the exploding reflector modeling and migration directly. This alleviates the need to subtract the source wavefield from the recorded one to obtain the imaging condition at the scattering point (reflectors).

While most of the modern seismic imaging methods perform imaging by separating input data into parts (shot gathers), we develop a formulation that is able to incorporate all available data at once while numerically propagating the recorded multidimensional wave.eld backward in time. While computationally extensive, this

approach has the potential of generating accurate images, free of artifacts associated with conventional approaches. We derive novel high-order partial differential equations in source-receiver-time domain. The fourth

order nature of the extrapolation in time has four solutions two of which correspond to the ingoing and outgoing P-waves and reduces to the zero-o.set exploding-reflector solutions when the source coincides with the

receiver. Using asymptotic approximations, we develop an approach to extrapolating the full prestack wave.eld

forward or backward in time.