页岩储层中同步压裂形成复杂缝网可行性研究

Feasibility of complex fracture networks under simultaneous fracturing in shale reservoirs

 赵志红¹ 黄超¹ 郭建春¹ 周月波²

西南石油大学油气藏地质及开发工程国家重点实验室，四川 成都 610500 中国石化中原油田分公司石油工程技术研究院，河南 濮阳 457001）

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China Research Institute of Oil Production Engineering and Technology, Zhongyuan Oilfield Company, SINOPEC, Puyang 457001, China)

 同步压裂能够更好地利用2个井筒中裂缝诱导应力干扰，降低地应力差异系数，使页岩油气藏产生更加复杂的裂缝形态。文中运用位移不连续理论，建立了二维平面裂缝诱导应力场数学模型，讨论了页岩储层形成复杂缝网所需要的地应力条件，分析了裂缝净压力、裂缝参数和原地应力场等因素对同步压裂形成裂缝网络复杂程度的影响规律。结果表明，裂缝净压力越大、裂缝长度越长、原地应力差异越小，页岩储层形成复杂缝网的可行性越大。研究结果对判断我国页岩油气藏能否应用同步压裂形成复杂缝网具有一定的理论指导意义。

 Simultaneous fracturing can make better use of the induced stress interference of the fractures in the two horizontal wells and reduce the geostress difference coefficient to produce more complex fracture network. Firstly, this paper applies the displacement discontinuity method to establish 2D induced stress field numerical model. Secondly, the stress conditions to form a complex fracture network in shale reservoirs are discussed. Finally, this article also analyses fracture net pressure, fracture parameters, in situ stress field, and other factors in shale reservoirs to generate complex fracture network in simultaneous fracturing. The results show that larger fracture net pressure, longer open cracks length and smaller in situ stress difference produce more complex fracture networks, which provides a theoretical guiding to the judge whether simultaneous fracturing technology can be applied to shale oil and gas reservoirs in China.

10.6056/dkyqt201605016