Application of Common-reflection-surface Technology from Stack to Prestack Time Migration

Common reflection surface (CRS) technology can be used in stack process to get simulated zero-offset section with higher S/N ratio than conventional method. However, poststack migration of CRS stacked data is not always satisfying due to serious suppression of diffraction wave and enhancement of reflection wave. Using kinematic parameters, Time migration result can be obtained directly from pre-stack data by extended CRS method. The so called “CRS prestack time migration” here is independent of macro velocity model as well as CRS stack. Meanwhile, property of high S/N ratio can be still preserved in migration section as stack section. Test results on synthetic data by this new approach show its promising application.