Stabilized viscoacoustic reverse time migration in the frequency domain and its application
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.
formation absorptionKolsky-Futterman modelviscoacoustic waveviscoacoustic reverse time mi-grationstabilization
万方数据
维普
