Regional staining reverse time migration algorithm based on energy-constrained factors

Abstract

Abstract Stained migration algorithms can improve the imaging result in some special structures, such as subsalt layers and steeply inclined layers, by introducing the complex domain. Conventional stained migration algorithms need to stain the target geological body precisely. However, in actual production, it is not possible to stain only the target geological body, which leads to inaccurate stained imaging results. So we propose a new regional staining algorithm based on energy-constrained factors. Derive the discrete form of the complex domain wave equation and the imaging formula of the imaginary migration result. Study the influence of the stained region boundary on seismic wave propagation when different migration velocities are input. Based on the difference in energy of the reflected waves generated at the stained region boundary and those generated by the target geological body, we propose positive and negative energy-constrained factors to constrain the interference waves by stained boundaries. The positive energy-constrained factor can filter out weak interference waves, and the negative energy-constrained factor can filter out strong interference waves. Numerical examples of a simple three-layer horizontal model and a complex salt model show that the new regional staining algorithm based on energy-constrained factors can increase the illumination of the target geological body and improve the imaging resolution of the target region, even when stained areas are imprecise.