Application of Low Signal-To-Noise Ratio Seismic Data Processing Technology in the Northern Margin of Qinshui Basin

In the northern margin of Qinshui Basin, the topographic relief is sharp, near surface lithology is complicated, and the thickness of loess is inhomogeneous. The problems of the seismic data in the research area is presented as low signal-to-noise ratio, distorted imaging of coal, and blurry shallow reflection, which restrict the exploration and development of coalbed methane. Based on geological requirements and seismic data characteristics, the low signal-to-noise ratio seismic data processing techniques of loess tableland area is optimized, and the quality of seismic data is improved. Firstly, the long wavelength static correction is improved through iterative processing of the first break picking and the tomographic static correction method; Secondly, using the noise suppression techniques with dividing frequency, velocity, area and domain to gradually suppress a variety of interference; Thirdly, applying comprehensive residual static correction processing with both surface consistent and non surface consistent method to enhance the in-phase of weak signals; Finally, the signal reconstruction technology with Matching Pursuit Fourier transform is used to raise the reflection characteristics of weak signals. The processing result shows that the signal-to-noise ratio of reprocessed seismic data is enhanced, the imaging of coal is more reasonable, the continuity of shallow reflection is better, and the imaging of fuzzy zone is significantly improved, which providing effectively support for regional geological research and coalbed methane exploration and development.