应力场数值模拟技术在致密气藏开发中的应用

Application of stress field numerical simulation on tight gas reservoir development

在地质建模的基础上,利用有限元数值模拟技术对苏里格气田靖A井区盒8段致密砂岩储层现今应力场的分布进行了定量模拟。模拟结果显示,研究区盒8段现今最大水平主应力分布在42~46 MPa,方向以N70°E~N85°E为主,在工区西北角向N50°E~N65°E偏转。现今最小水平主应力分布在26~29 MPa。高压气井主要分布在构造应力高值区,揭示了构造应力场对致密气藏原始地层压力的控制作用。进一步分析了构造应力场对苏里格气田水平井轨迹设计、孔眼方向设计、压裂设计以及致密气藏优势渗流方向的控制作用,研究结果可为气田水平井井网部署及压裂设计提供借鉴。

Based on the geological model,current stress field of He 8 tight gas reservoir in zone A is simulated by finite element numerical simulation technology.Simulation result shows that,current maximum horizon principal stress of He 8 interval in zone A is between 42~46 MPa,main bearing of trend is N70°E~N85°E,which deflected to N50°E~N65°E at northwest corner of zone A.Current minimum horizon principal stress is between 26~29 MPa.High pressure gas wells main locate at high tectonic stress areas,which revealed the control action of tectonic stress field to initial formation pressure of tight gas reservoir.Meanwhile,the control action of tectonic stress field on horizontal well trajectory design,perforation bearing design,fracturing optimization,prevailing filtration direction has been analyzed.The research findings could guide on horizontal well network disposition and fracturing optimization.