Method

Ray-based migration schemes, carried out in the angle domain, offer several advantages over conventional Kirchhoff migration methods:

  1. The migration result is generated in dependence on incidence angle. No explicit knowledge of true local dip or post-migration mapping between offset and angle is required.

  2. There is no need for regularizing the input data.

  3. True-amplitude weighting is applied to the seismic trace amplitudes. Migration amplitudes are, thus, proportional to the local angle- and azimuth-dependent reflection coefficient.

  4. By identifying rays in the angular domain, GRT solves problems in situations of multi-pathing in a natural way while Kirchhoff migration has severe problems in storing and accessing multiple ray events. GRT is, thus, essentially an all-arrival migration.