A fine-scale prediction method for small-scale faults and fractures in shale gas reservoirs
LYU Qi-Biao1(), WU Qing-Jie2, LI Shu-Guang1, WANG Ren-Fu1
1. Research Institute of Exploration and Development, Southwest Oil & Gas Company, SINOPEC, Chengdu 610041, China 2. Southwest Oil & Gas company, SINOPEC, Chengdu 610041, China
Small- and micro-scale faults fractures (fractures and faults with fault throw less than 10 m) that originally developed in shale strata have a significant impact on the probability of penetration, stimulation volume, and production capacity of high-quality reservoirs in horizontal well sections. Therefore, it is critical to conduct fine-scale fault and fracture prediction. However, any single method struggles to accurately identify and predict these faults and fractures. Based on the developmental conditions of small-and micro-scale faults and fractures in the shale gas reservoirs of the Longmaxi Formation in the southern Sichuan Basin, this study conducted forward modeling, response mechanism analysis, and characterization of fracture responses, developing a prediction method integrating predicting and modeling. Furthermore, this study preferentially investigated techniques including seismic data processing, small-scale fault and fracture prediction, multi-scale fracture modeling, and fusion characterization. The results of the proposed method were highly consistent with the geological anomalies including small and micro-scale faults, lost circulation, and inter-well pressure channeling observed during the drilling of horizontal wells in the shale gas reservoirs of the Longmaxi Formation. Furthermore, these results exhibit a strong positive correlation with the single-well production capacity. All these corroborate that it is feasible to use this method to predict small- and micro-scale faults and fractures. This study can serve as a reference for predicting small-scale faults and fractures in other strata of the same type.
吕其彪, 吴清杰, 李曙光, 汪仁富. 页岩气层小微尺度断缝精细预测方法[J]. 物探与化探, 2025, 49(2): 299-311.
LYU Qi-Biao, WU Qing-Jie, LI Shu-Guang, WANG Ren-Fu. A fine-scale prediction method for small-scale faults and fractures in shale gas reservoirs. Geophysical and Geochemical Exploration, 2025, 49(2): 299-311.
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doi: 10.3969/j.issn.1000-1441.2022.02.001
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