| Seismic prediction of formation pressure is of great significance to the evaluation of powerful gas-producing
areas and exploration and development of shale oil and gas reservoirs. The study area of western Chongqing is a favorable
area for exploration and development of deep shale gas. The shale gas resources in the area are abundant, and formation
overpressure is common in the reservoirs. However, due to complex geological conditions, it is difficult to accurately
obtain the formation compaction background trend while using conventional formation pressure seismic prediction
methods, making it difficult to properly solve the seismic prediction of formation pressure. Usually, the formation
compaction background trend is obtained directly through well trend fitting. The established formation compaction
background often has large errors, resulting in inaccurate formation pressure prediction. Therefore, this paper constructs
the formation compaction background trend through actual logging analysis, based on rock physics theory and rock
physics model, which effectively improves the modeling accuracy of formation compaction background trend. By
substituting the normal compaction background trend and measured parameters constructed by petrophysical modeling
into the bulk modulus equation, the seismic prediction of formation pressure of the study area of western Chongqing in the
Sichuan Basin is achieved, and good application results are achieved. By comparing with the actual drilling measured
results, it is found that the predicted formation pressure parameters are consistent with the measured formation pressure
parameters of multiple wells, indicating the applicability and accuracy of the method. |
