Abstract:
Temporary plugging and diverting fracturing technology is the key method for the efficient development of shale gas reservoirs in the Sichuan Basin. Current operations, however, still mainly rely on field experience. To further improve the effects of temporary plugging and diverting fracturing in this area, this paper summarizes the characteristics of shale reservoirs in the Sichuan Basin and reviews the application history of the temporary plugging and diverting fracturing technology. In addition, it presents the major progress of this technology in terms of temporary plugging materials, temporary plugging mechanisms, fracture diverting mechanisms, temporary plugging techniques, and field applications. Therefore, it clarifies the challenges faced by field operation and puts forth relevant development suggestions. Micro-seismic and field production data demonstrate that near-wellbore and far-field temporary plugging and diverting fracturing technologies significantly improve the fracturing stimulation effect of shale gas reservoirs in the Sichuan Basin. The main performance parameters of temporary plugging balls and particle temporary plugging agents commonly used in shale gas reservoirs meet the requirements of temporary plugging and diverting fracturing in the middle and shallow reservoirs and some deep reservoirs. Nevertheless, theoretical support is still lacking in the selection of temporary plugging materials and the optimization of operation parameters, and there are still challenges caused by the complex reservoir conditions of deep shale reservoirs. Work in the future should focus on enhancing the formulation of evaluation standards for temporary plugging materials, research on the temporary plugging mechanisms of various temporary plugging materials, and the development of new temporary plugging materials. In this way, theoretical references can be provided for the operation parameter optimization of temporary plugging and diverting fracturing, and the improvement in operation effects.