An Adaptive Phase Shift and SSFPI Method for Prestack Depth Migration
Nanxun Dai, C. Willacy, Y. Sun · 2002
E-32 AN ADAPTIVE PHASE SHIFT AND SSFPI METHOD FOR PRESTACK DEPTH MIGRATION 1 NANXUN DAI CHRIS WILLACY and YONG SUN GX Technology 5847 San Felipe Suite 3500 Houston TX 77057 USA Summary We present a wave equation prestack depth migration method that employs phase-shift and split-step Fourier plus interpolation (SSFPI) algorithms for wavefield downward extrapolation. These two approaches are adaptively implemented according to velocity model structure. Phase shift is used in constant velocity bodies such as the water layer and salt masses. SSFPI is used in the sedimentary section where velocity varies. The separation of water and salt from the