Hydraulic fracturing is critical for extracting shale gas in the subsurface. The treatment technique of multistage hydraulic fracturing is widely used to maximize production. In multistage hydraulic fracturing, not all pumping stages make the same contribution for production, although the designed stimulation process is almost same in every pumping stage. In this study, we characterize the microseismic responses of hydraulic fracturing. Significant variations of microseismic characteristics are observed among the different pumping stages. Pre-existing natural fractures are examined along the horizontal well in selected stages. Combined with the Mohr’s circle analysis, results of the fracture study show that induced hydraulic fractures can be captured by pre-existing natural fractures. Induced hydraulic fractures are simulated by the unconventional fracture model (UFM), and the result reveals that the stress-shadow effect diverts the direction of hydraulic fractures. The diverted hydraulic fracture affects the development of the hydraulic fracture network, which has influence on production. The treatment of two-step pumping is investigated by application of hydraulic diffusivity. Hydraulic fracturing performance and production could be optimized by the treatment of two-step pumping in a single stage. The second pumping creates new fractures and fills the fractures with additional proppants to maintain production for a long duration.

水力压裂对于地下开采页岩气至关重要。多级水力压裂的处理技术被广泛使用以最大化产量。在多级水力压裂中，尽管设计的增产工艺在每个泵送阶段几乎相同，但并非所有泵送阶段都对生产做出了相同的贡献。在这项研究中，我们表征了水力压裂的微地震响应。在不同的泵送阶段之间观察到微震特征的显着变化。在选定的阶段中，沿水平井检查先前存在的天然裂缝。结合莫尔圆分析，裂缝研究的结果表明，可以通过预先存在的天然裂缝来捕获诱发的水力裂缝。用非常规裂缝模型（UFM）对诱发的水力压裂进行了模拟，结果表明，应力阴影效应使水力压裂的方向发生了变化。改道的水力压裂影响水力压裂网络的发展，对生产产生影响。利用水力扩散系数研究了两步抽水的处理方法。水力压裂性能和产量可以通过在一个阶段中进行两步泵送进行优化。第二次泵送产生新的裂缝，并用额外的支撑剂填充裂缝，以长期维持产量。改道的水力压裂影响水力压裂网络的发展，对生产产生影响。利用水力扩散系数研究了两步抽水的处理方法。水力压裂性能和产量可以通过在一个阶段中进行两步泵送进行优化。第二次泵送产生新的裂缝，并用额外的支撑剂填充裂缝，以长期维持产量。改道的水力压裂影响水力压裂网络的发展，对生产产生影响。利用水力扩散系数研究了两步抽水的处理方法。水力压裂性能和产量可以通过在一个阶段中进行两步泵送进行优化。第二次泵送产生新的裂缝，并用额外的支撑剂填充裂缝，以长期维持产量。