同步压裂对井间裂缝特性的影响

Influence of synchronous volume fracturing on interwell fracture characteristics

李玉伟 艾池 张博文 栾瑛琪 淡利华 王红芹

东北石油大学提高油气采收率教育部重点实验室，黑龙江 大庆 163318 中国石油大学（北京）石油工程学院，北京 102249 中国石化中原油田分公司采油二厂，河南 濮阳 457532

MOE Key Laboratory for Enhanced Oil and Gas Recovery, Northeast Petroleum University, Daqing 163318, China College of Petroleum Engineering, China University of Petroleum, Beijing 102249, China No.2 oil Production Plant, Zhongyuan oilfield Company, SINOPEC, Puyang 457532, China

针对多井同步体积压裂优化设计的需求，在假设岩石为均质、各向同性材料的条件下，基于弹性力学理论，建立了同步体积压裂过程中的二维诱导应力场计算模型；考虑到井间裂缝诱导应力对原始水平主应力的影响，结合裂缝转向机理，得出压裂裂缝转向形成网状裂缝的力学条件。研究结果表明：可通过改变同步体积压裂的裂缝施工参数，改变诱导应力场，调整井间地层的最大、最小水平主应力差值，诱导裂缝转向形成网状裂缝；改变与设计转向裂缝相邻或距离较近裂缝的参数时，诱导应力场变化明显，利于裂缝转向。

In accordance with the requirements of the optimum design of synchronous volume fracturing, the calculation model of two-dimensional induced stress field in the process of synchronous volume fracturing has been established based on the theory of elastic mechanics, assuming that the rock is homogeneous and isotropic material. Considering the influence of inter-well induced stress on the original horizontal principal stress, the mechanics conditions that promote the fracturing fracture steering to form network fractures have been acquired combining with the fracture steering principle. The results show that through changing the fracture operation parameters of synchronous volume fracturing, the difference of largest and smallest horizontal principal stress of inter-well formation can be adjusted because of the change of induced stress field. It can induce fractures steering to form network fractures. The induced stress field changes obviously when the parameters of fractures which are adjacent or at close range to the designed fractures have been changed, which is beneficial to fracture steering.

10.6056/dkyqt201306025