Prestack seismic inversion with structural constraints

Abstract

Prestack seismic inversion usually suffers from a lower signal-to-noise ratio, which could result in unstable inversion results. The conventional multitrace lateral constrained inversion blurs steeply dipping layers, whereas the simple structural constrained inversion is affected by noise. To solve this issue, an inversion method with multiple constraints is proposed, which include (1) a local smoothing operator is used to suppress the inversion anomalies caused by data noise, (2) a difference operator is used to protect the stratum boundary, and (3) a structural dipping constraint is used to enhance the characterization of the possible dipping stratum. The multiconstraint inversion (MCI) method suppresses the inversion anomalies caused by data noise without blurring the stratum boundary. The effects of different constraints in the inversion process and the influence of noise on the inversion results are analyzed. In MCI, the regularization coefficient of each constraint operator is dynamically changed, thereby controlling the significance of each regularization term in the inversion. The proposed algorithm is tested on synthetic and field data, which demonstrate its effectiveness and improved accuracy on the inversion results.