层理页岩水平井井眼方位优化  

Optimization of Horizontal Wellbore Azimuth in Bedding Shales

作　　者：王倩 项德贵 王思敏 史肖燕 

机构地区：[1]中国石油集团钻井工程技术研究院,北京102206

出　　处：《长江大学学报（自科版）（中旬）》2015年第3期42-46,5,共5页Journal of Yangtze University(Nature Science Edition)

基　　金：国家科技重大专项(2011ZX05021-006)

摘　　要：由于页岩气藏层理发育,页岩气藏水平井与常规油藏水平井相比,井眼不稳定问题及不易压裂问题更为突出,需要提出兼顾两者的水平井眼方位优选方法。采用理论研究和数值模拟的方法,详细分析了走滑断层地应力状态下页岩层理倾角和走向对水平井方位优化的影响。研究表明,层理倾角对水平井井眼方位优化影响很大。层理倾角较小时,页岩水平井易于压裂的方位与井眼稳定的方位是一致的,选择水平最大地应力方向或靠近水平最大地应力方向为优选方位。层理倾角较大时,页岩水平井易于压裂的方位与井眼稳定的方位几乎是相反的,需要选择维持井眼稳定要求的钻井液密度不高,且相对易于压裂的方位。层理走向对水平井井眼方位优化几乎没有影响。Because of bedding development in the shale gas reservoirs,the problem of wellbore instability and hard fracturing in horizontal wells in shale gas reservoirs was more obvious than that in conventional reservoirs.It was needed to propose a method for optimizing horizontal well azimuth for both reservoirs.By using the theoretical study and numerical simulation,the influence of shale bedding inclination and strike under in-situ stress on the optimization of horizontal well azimuth was studied in detail.The result shows that there is serious influence of bedding inclination on the optimization of its azimuth.When the inclination is less,its fracturing azimuth is consistent with that of its wellbore stability,the optimized position is the azimuth with maximum in-situ stress or near the maximum in-situ stress.When shale bedding inclination is bigger,the azimuth of easy fracturing and the azimuth of stable borehole of shale horizontal well is almost opposite.It's needed to choose the azimuth,where not high drilling fluid density is needed for maintaining borehole stability and relatively easy for fracturing.The bedding strike has little impact on the optimization of horizontal well azimuth.

关 键 词：页岩 层理倾角 层理走向 水平井 井眼方位优化 

分 类 号：TE22[石油与天然气工程—油气井工程]