## 5 Conclusions and Recommendations  
Kirchhoff pre-stack depth migration is the most flexible and effective method for pre-stack seismic data imaging and has high computational efficiency. Our principal innovation lies in the integrated use of model constraints within the Kirchhoff pre-stack depth migration framework. Unlike traditional approaches that apply true-amplitude migration or velocity inversion in isolation, our methodology synergistically unites iterative  
Figure 14: Comparison of migration effects of Inline120 pre-stack time migration (**a**) and depth migration (**b**) in work area. Figure 13: Inline80 anti-alias operator parameter test comparison diagram: (**a**) 0.25; (**b**) 1; (**c**) 2.  
velocity inversion, denoising, and model constraint mechanisms. This novel combination not only elevates imaging fidelity under severe lateral velocity contrasts but also streamlines parameter tuning and enhances reproducibility, representing a significant advancement in pre-stack seismic imaging technology. The following conclusions are drawn:  
1. The Kirchhoff pre-stack depth migration method based on model constraints is used to study the pre-stack depth migration imaging of theoretical model data. The results show that after removing the direct wave, the clarity and continuity of the shallow and deep reflection events are significantly improved, and the energy distribution of each interface is uniform, which significantly improves the imaging accuracy and signal-to-noise ratio. The addition of model constraints further optimizes the imaging results, making the layered interface features clearer and in good agreement with the model structure. The numerical model verifies the effectiveness of the proposed method in improving the imaging accuracy under complex geological conditions. 2. The signal-to-noise ratio of seismic data in complex structural areas is often very low. The initial velocity and input gather of depth migration are highly dependent on the signal-to-noise ratio of the data. The combined denoising technology, comprehensive velocity modeling method, and constrained velocity inversion (CVI) method are used to maximize the protection of effective signals and provide high-fidelity data for depth migration. The Kirchoff integral migration technique improves the continuity of the phase axis of the pre-stack depth migration imaging profile, the imaging is clearer, and the resolution is significantly improved. 3. Comparing the imaging results of pre-stack time migration and pre-stack depth migration, the Kirchoff integral pre-stack depth migration method based on model constraints can solve the technical difficulties of inaccurate migration imaging caused by drastic changes in lateral velocity, effectively improving the signal-to-noise ratio and resolution of seismic wave imaging and better solve the problem of complex structural imaging. The fault breakpoint position is clearer, and the wave group characteristics are obvious, which provides an effective technical method for complex geological structure detection imaging. 4. Through the application of pre-stack depth migration imaging technology in complex geological structures, the boundary characterization of geological structures can be enhanced, the imaging accuracy can be greatly improved, the exploration accuracy can be effectively improved, and the problem of poor post-stack migration imaging can be solved. This provides a solid data foundation for the geological structure of the study area.