Application of time-lapse seismic technology to predict residual gas in D gas field of Yinggehai Basin

Time-lapse seismic technology is one of the effective means for predicting residual gas in mature gas fields. By taking the D gas field in the Yinggehai Basin as the research object, residual gas prediction was conducted by combining conventional 3D towing line and 3D OBN seismic data acquired in different periods. The analysis of rock physics and time-lapse seismic response characteristics, consistent processing, and comprehensive interpretation of time-lapse seismic differences were also performed. A rock physics model was innovatively constructed by dual calibration of logging curves and core acoustic measurements, which improved the reliability of the model. Verified by measured production data from 24 development wells, the average accuracy of predicted gas saturation and pressure at well points reached 81.8% and 83.3%, respectively. On this basis, potential blocks of residual gas were optimized by combining structure, reservoir thickness, and production dynamics to guide the deployment of development and adjustment wells, achieving good practical application results. This study provides a new idea for the application of non-repetitive time-lapse seismic technology (combined towing line and OBN) in residual gas prediction.