Double-phase-shift filtering method for eliminating harmonic distortion in processing slip-sweep vibroseismic signals

Although simple and efficient for eliminating harmonic distortion of vibroseismic data, the single-phase-shift filtering method is less effective for dealing with complex signals such as white noise and signals recorded by slip-sweep vibroseis survey, so it failed to be put into actual application. In view of this situation, we propose a double-phase-shift filtering method. It manipulates and polishes the original phase shift from the traditio-nal phase shift method, and at the same time carries out another phase shift to process the signal that the single-phase-shift filtering method cannot process. Applied on model data, the double-phase-shift method can suppress harmonic distortion more effectively than the single-phase-shift me-thod. Then we applied the double-phase-shift filtering method to slip-sweep signals, and analyzed the applicable conditions. In view of the fact that raw seismic data are composed of various reflections with different intensity, a subsurface model with multiple reflections should be established, and the frequency ratio of signals should be consi-dered in order to discuss the applicability of the double-phase-shift method. Applied for raw data and compared with the single-phase-shift filtering method, the double-phase-shift method is better in suppressing harmonic distortion and worthy promoting. © 2021, Editorial Department OIL GEOPHYSICAL PROSPECTING. All right reserved.