Static correction method and device in converted shear wave

Abstract

The invention discloses a static correction method and a device for a converted S-wave. The method comprises steps: P-wave and S-wave speed ratio sequence scanning is carried out on acquired seismic wave data resources, and the optimal speed ratio is determined; according to the optimal speed ratio, a first time difference in the S-waves is calculated, and first-time static correction is carried out; an indicator horizon is picked on a P-wave stack section and a converted S-wave stack section; the indicator horizon is stretched to time corresponding to the converted S-wave stack section, a second time difference of the two stack sections is obtained, and second-time static correction is carried out based on the second time difference; the stretched P-wave stack channel serves as a model channel, a converted S-wave ACP channel collection at the corresponding position via two times of static correction correlates with the model channel, a third time difference between each channel in the ACP channel collection and the model channel is calculated, and third-time static correction is carried out. Additional material acquisition is not needed, a good S-wave first arrival is not required in the resources, and thus, large-scale production and processing are facilitated.

Description

technical field [0001] The invention relates to geological exploration and oil and gas field development, more specifically, to a static correction method and device in converted shear waves. Background technique [0002] Converted wave static correction has always been a difficult problem in multicomponent processing. Since the low-velocity zone of the shear wave is deeper than the water surface, and the fluctuations are large, the velocity of the shear wave is lower than the velocity of the longitudinal wave in the shallow layer of the surface. Therefore, this leads to a large amount of P-SV static correction, which is generally 2 to 10 times that of the longitudinal wave. In addition, the time difference between Tao and Tao changes drastically. [0003] The converted wave static correction is composed of the P wave static correction at the source point and the S wave static correction at the receiving point. Statics can be decomposed into low frequency and high frequen...

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Problems solved by technology

Therefore, due to the problem of data quality, there are not many regions where this method can be applied, so it is limited in actual production and application

[0007] Although the common receiver point stacking cross-correlation static correction method is feasible in regions with slow structures, it can only obtain the middle-long wavelength and short-wavelength static corrections that affect the imaging quality, but cannot solve the long-wavelength static corrections that affect the structural form. quantity problem

The static correction method using Rayleigh surface waves to retrieve surface shear wave velocity requires a special acquisition method with small track spacing, and this method is still in the experimental stage, and basically cannot be used in large-scale practical production applications

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