Abstract：At present, there are many static correction methods for converted waves, which have become an indispensable part of multi-component exploration. However, these methods still face some practical problems:① The surface wave inversion method faces the problem of surface wave divergence and low signal-to-noise ratio of surface wave in complex exploration areas, and it has difficulty in determining dispersion period and picking up dispersion curves. ② In the static correction method for the first arrival wave, the first-arrival signal-to-noise ratio of converted waves by tomography inversion and refraction method is low, and it is difficult to pick up the first arrival, especially in complex exploration areas. ③ The structural constraint method of common detector gather stacking longitudinal wave requires that the change in underground reflection interface should be relatively gentle or horizontal. Therefore, the above methods are not suitable for static correction of converted waves in complex exploration areas. As a result, a static correction method for converted waves based on complex structures is proposed. The specific steps are as follows:① We eliminate the structural items in the static correction of converted waves by horizon flattening to overcome the limitation of the horizontal interface. First, we pick up the structural horizon with a high signal-to-noise ratio in P-P wave CMP stacking, calculate the horizon flattening projection moveout, and use the moveout to flatten the pre-stack data. ② We convert the flattened horizon data to the common receiver point domain and complete the velocity analysis of the P-P wave of the common receiver point again so that each common receiver point trace has the same velocity. This process eliminates the inter-trace dynamic correction error caused by the drastic change in lateral velocity in complex structures and the low accuracy of velocity analysis. It can not only enable the common receiver points to realize in-phase stacking and improve the signal-to-noise ratio but also reduce the impact of a low velocity accuracy on the residual static correction of seismic traces. ③ We convert the projection moveout of the flattened P-P wave structural horizon into to P-SV domain to flatten the pre-stack data of the P-SV wave, restart the velocity analysis of the P-SV wave in the common receiver point domain, improve the stacking signal-to-noise ratio and resolution of P-SV wave common detector gather, and finally enhance the stacking horizon picking accuracy and efficiency of P-SV wave common detector gather. Through structural horizon flattening and velocity analysis in the common receiver point domain, we further use the static correction method for converted waves with P-P wave structural constraints to improve the calculation accuracy and efficiency of static correction of converted waves based on complex structures.
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