库车坳陷超深油气藏钻井井壁稳定性分析研究及应用
Analysis and Application of Drilling Wellbore Stability of Ultra-Deep Reservoir in Kuqa Depression
刘磊 1张辉 2徐珂 2来姝君 1袁芳1
作者信息
- 1. 中国石油天然气集团有限公司超深层复杂油气藏勘探开发技术研发中心,新疆库尔勒 841000;中国石油天然气股份有限公司塔里木油田公司,新疆库尔勒 841000
- 2. 中国石油天然气集团有限公司超深层复杂油气藏勘探开发技术研发中心,新疆库尔勒 841000;中国石油天然气股份有限公司塔里木油田公司,新疆库尔勒 841000;新疆维吾尔自治区超深层复杂油气藏勘探开发工程研究中心,新疆库尔勒 841000;新疆超深油气重点实验室,新疆库尔勒 841000
- 折叠
摘要
库车坳陷克拉苏构造带超深油气储层具有埋深大、温度高、岩性变化大、应力场高等特点,导致基于常规井壁稳定性分析方法计算的钻井泥浆密度窗口不准,造成钻进过程中井壁失稳频发,给钻井安全和环境保护带来隐患.通过考虑温度效应对井筒应力的影响,加入基于Mohr-Coulomb破坏准则的弱面(裂缝)失稳条件,提出了一种根据岩石、弱面不发生剪切失稳的最小泥浆密度和不发生张性失稳的最大泥浆密度,以及孔隙压力和最小水平主应力的当量泥浆密度6个参数,共同确定超深储层钻井安全泥浆密度窗口的取值方法.实际资料应用结果表明,该方法对库车坳陷博孜区块超深复杂地层的坍塌压力和漏失压力的预测具有很好的适用性和准确性,为实际钻井施工设计提供有效参考.
Abstract
The ultra-deep oil and gas reservoir in Rasu structural zone of Kuqa depression has the characteristics of large buried depth,high temperature,large lithologic change and high stress field,which leads to the inaccurate drilling mud density window based on the conventional wellbore stability analysis,resulting in frequent instability of the wellbore during the drilling process,and brings hidden dangers to drilling safety and environmental protection.By considering the influence of temperature effect on the borehole stress and adding the weak surface(fracture)instability condition based on Mohr-Coulomb destruction criterion,we proposed a method to determine the safe slurry density window of ultra-deep reservoir drilling according to six parameters:the minimum slurry density for shear instability and the maximum slurry density for tension instability in rock and weak surface,and the equivalent slurry density of pore pressure and minimum horizontal main stress.The application results of real data show that this method has good applicability and accuracy for the prediction of collapse pressure and leakage pressure in the ultra-deep complex formation in Bozi block of Kuqa depression,and can provide effective reference for the actual borehole drilling design.
关键词
井壁稳定性/超深裂缝气藏/井筒应力/岩石破裂准则Key words
wellbore stability/ultra-deep fracture gas reservoir/borehole stress/rock rupture criteria引用本文复制引用
基金项目
中国石油天然气股份有限公司重大科技专项(2023ZZ14-03)
出版年
2024
国家科技期刊平台
NSTL
万方数据