裂缝性储层射孔井起裂压力影响因素分析  

Research on Influential Factors of Initiation Pressure in Fracture Formation for Perforated Boreholes

作　　者：丁乙[1] 刘向君[1] 罗平亚[1] DING Yi;LIU Xiangjun;LUO Pingya(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation（Southwest Petroleum University）,Chengdu 610500,P.R.China)

机构地区：[1]油气藏地质及开发工程国家重点实验室(西南石油大学),成都610500

出　　处：《应用数学和力学》2018年第7期811-820,共10页Applied Mathematics and Mechanics

基　　金：国家自然科学基金(重点项目)(41772151);四川省应用基础研究计划项目(2014JY0092);国家科技重大专项(2011ZX05020-007-06)~~

摘　　要：水力压裂是目前最为常用、有效的储层增产措施.为了更好地进行压裂优化设计,提高储层改造效果,需要开展水力压裂裂缝起裂和扩展机理研究.裂缝性储层发育大量天然裂缝,具有强均质性,导致该类储层水力裂缝起裂与延伸规律复杂,具有强不确定性.因此,该文针对裂缝性地层起裂机制,基于张性起裂准则,考虑天然裂缝数量、产状及射孔工程参数,建立裂缝性储层起裂压力预测模型.分析结果表明:天然裂缝面存在,易导致水力裂缝沿裂缝面起裂,从而降低起裂压力.尤其随裂缝数量增加,起裂压力下降趋势更为明显.同时,起裂压力分布受工程参数控制,在高方位角和低井斜角条件下,起裂压力较大.研究成果对裂缝性储层压裂作业具有一定理论指导意义.Hydraulic fracturing is the most common and effective stimulation treatment. To better the fracturing design and improve the stimulation treatment,the mechanism of fracture initiation and propagation was investigated. In fracture formation,lots of natural fractures exist,having strong anisotropy and causing extreme complication and uncertainty of fracture initiation and propagation. Therefore,the mechanism of fracture initiation was stressed with the tensile criterion to establish the initiation pressure model in view of the natural fracture number,the occurrence and the intersection between perforation and fracture.The results indicate that,the natural fracture tends to cause initiation along the fracture plane and decrease the initiation pressure. In particular,with an increasing number of fracture planes,this decline will be more significant. Besides,the distribution of initiation pressure is related to several engineering parameters.For a high perforation azimuth and a low wellbore deviation,the initiation pressure will be relatively larger.The findings can offer reference for hydraulic fracturing in application.

关 键 词：裂缝性储层 水力压裂 射孔 起裂压力 

分 类 号：TE355.5[石油与天然气工程—油气田开发工程]