Incorporating Tomographic Static Correction in the Seismic Processing of a CBM Reservoir with Complex Surface Conditions

Abstract The first step in processing the determination of near-surface velocity structures is critical. In addition to improper static adjustments, a poor near-surface velocity model causes the rays predicted by the model to deviate from their actual ray paths. Due to the cumulative nature of this ray path deviation, even a small error in the near-surface velocity model can result in momentous errors in calculating the ray path and travel time. Furthermore, the deviation can notably degrade the seismic image at depth, particularly in regions with significant lateral velocity variations. A seismic model with significant lateral velocity variations and bare bedrock was built to perform theoretical calculations. The concept of first arrival tomographic static correction was also examined. Numerical simulation techniques were used to study the conditions and application consequences of the first arrival tomographic static correction, providing a reference for the static correction of challenging surface coal bed methane (CBM) seismic data. The findings demonstrate that tomographic static correction is better suited for processing complicated surface CBM seismic data and can effectively handle the problems of surface undulation and lateral velocity fluctuation, which are critical for improving the accuracy of CBM exploration.