The absorption attenuation and dispersion of seismic waves are both related to frequency.Therefore,it is theoretically and physically reasonable to study the viscoacoustic reverse time migration in the frequency do-main.Similar to that in the time domain,the method in the frequency domain will inevitably cause the amplifica-tion of high-frequency noise while compensating for the absorption attenuation,thus lowering the stability and imaging accuracy of the migration algorithm due to the instable compensation.To solve this problem,we use the Kolsky-Futterman model to derive a viscoacoustic wave equation in the frequency domain,and then achieve a stabilized viscoacoustic reverse time migration.First,we derive the above equation,where the amplitude at-tenuation is decoupled with the phase velocity dispersion,based on the Kolsky-Futterman model.Then,based on the decoupling characteristics of the equation,we construct a stabilized absorption attenuation compensation operator by utilizing the ratio of the dispersion-only and viscoacoustic wavefields.Finally,we use the stabilized operator to perform absorption attenuation compensation on both source forward wavefields and receiver back-ward wavefields,and further apply the cross-correlation imaging condition to perform the viscoacoustic migra-tion imaging on the underground structure.The experiments and data applications show that the proposed method can effectively suppress the amplification of high-frequency noise while compensating for the absorp-tion,ensuring the stability,imaging accuracy,and quality of the migration algorithm.
关键词
地层吸收/Kolsky-Futterman模型/黏声波/黏声波逆时偏移/稳定化
Key words
formation absorption/Kolsky-Futterman model/viscoacoustic wave/viscoacoustic reverse time mi-gration/stabilization
维普
万方数据