An efficient 3D wave-equation pre-stack time migration for high-density and wide-azimuth data

Abstract The sharp increase in data size of the high-density and wide-azimuth seismic acquisition makes processing routines very challenging. To reduce turn-around time pre-stack migration (PSTM) for large-scale field (terra to petabyte size), we present an efficient wave-equation PSTM that is approximate version double-square-root (DSR) moderate lateral velocity variation. By converting DSR dispersion relation into vertical-time domain ignoring offset-dip term, a novel common-offset ray parameter developed. Meanwhile, (i.e. offset plane waves) can be formed by applying linear Radon transform common middle point CMP) gathers. enhance signal-to-noise ratio conventional transform, integrate result over azimuth, yielding azimuth-independent waves are well suited irregular sampling uneven distribution. Furthermore, split-step Fourier method introduced extrapolate wavefield efficiently. Since migrated independently, image gathers (CIGs) generated naturally sorting sections parameters. A 3D test demonstrates efficiency effectiveness proposed method, making it promising industrial-sized processing.