同步压裂缝网形成机理研究进展

Advances of Mechanism Study of Fracture Networks Formed by Simultaneous Fracturing Process

同步压裂技术是实现页岩气、煤层气等非常规天然气储集层改造的新兴技术,揭示裂缝延伸的力学机理是进行施工参数优化的基础。研究表明,多裂缝同步延伸诱导应力场及其天然裂缝作用机制共同确定了同步压裂裂缝展布情况;裂缝网络工程方法是目前研究同步压裂裂缝延伸模型最好的手段;优化施工参数主要在于优化裂缝条数、裂缝间距、净压力和水力裂缝几何尺寸,以实现最大程度诱导应力场形成复杂裂缝网络。

Simultaneous fracturing process is a new technique for reservoir improvement of unconventional gas, such as shale gas and coal bed methane. Revealing the mechanical mechanism of fracture propagation is the basis of optimizing treatment parameters. The study shows that multi-fracture simultaneous propagation may alter the stress field and these fractures can interact with natural fractures. Both of them co-determine the pattern of fracture network during the fracturing process. Fracture network engineering （FNE） is the best method for study of such a model for fractures propagation at present. To achieve complex fracture networks by inducing in-situ stress field, the param-eters such as number of fractures, distance between fractures, net pressure and the geometry of hydraulic fractures should be optimized.