裂缝性岩样应力敏感性实验研究  

EXPERIMENTAL STUDY OF STRESS SENSITIVITY OF FRACTURE ROCK

作　　者：刘四海[1] 张浩[2] 刘金华[1] 樊红旗[3] 

机构地区：[1]中国石化石油工程技术研究院 [2]成都理工大学能源学院 [3]中国石油长庆油田分公司

出　　处：《钻采工艺》2011年第6期14-15,26,共3页Drilling & Production Technology

基　　金：国家自然科学基金"应力扰动地层裂缝开启和闭合机理研究"项目(编号:51104025);国家重大专项"中东中亚富油气区复杂地层深井钻完井技术"项目(编号:2008ZX05031-004)的研究成果

摘　　要：川东北地区裂缝性地层存在严重的钻井液漏失问题,做好防漏堵漏工作的基础是需要认识储层初始裂缝宽度,并对钻井过程井壁地层裂缝变化规律进行研究。结合钻井过程,对应力敏感实验设备和实验程序进行了改进,设置了新的应力敏感实验方法,模拟了地层压力、围压和井筒流压条件下设置的实验方法更加符合钻井过程应力变化的实际。裂缝性碳酸盐岩应力敏感性实验结果显示,以原地有效应力点为中心,随着井筒钻井液液柱压力的增大裂缝张开,随井筒钻井液柱压力降低,裂缝闭合,而裂缝张开的幅度比裂缝闭合的幅度更大。因此,研究压裂液应力扰动条件下裂缝宽度变化能够对防止漏失提供基础依据。There are serious drilling fluid leakage problems in fractured formation of Northeast Sichuan, working out leak-proof sealing measures must recognize the initial crack width, and research the change laws of formation fracture during drilling. Combined with drilling process, stress-sensitive experimental equipment and experimental procedures have been improved, considering the formation pressure, confining pressure and wellbore flowing pressure, a new stress-sensitive experimental methods was established which accord with the actual stress change in drilling process. The stress sensitivity test results of fractured carbonate rocks showed that with the wellbore fluid column pressure increase, crack opening, with the wellbore fluid column pressure drop, crack closure, and crack opening magnitude was bigger than the magnitude of crack closure.

关 键 词：裂缝 钻井液 漏失 防漏 裂缝宽度 应力敏感性 

分 类 号：TE21[石油与天然气工程—油气井工程]