Wave Equation Migration Using Isochron Rays

摘要

The migration of a single seismic trace produces an image where the amplitudes are distributed along isochron surfaces. This image can be interpreted as a superposition of snapshots taken from a propagating isochron in an equivalent velocity media, i.e. an isochron-field. We present an isochron-field migration method which is comprised of three steps: equivalent velocity computation, data conditioning, and application of a standard zero-offset wave-field extrapolation migration algorithm. We suggest the term equivalent exploding reflector model for the hypothetical model that theoretically supports our imaging approach. The presented methodology extends the use of zero-offset wave-equation imaging algorithms to finite-offset gathers. We successfully applied the approach for depth migrate a common-offset gather. The methodology presents some features that can facilitate the implementation of parallelized migration velocity analysis algorithms.