摘要
以往对复压前地应力场的研究仅限于机理探讨,缺乏一个完整系统的地应力场计算模型来定量描述垂直裂缝井重复压裂前各种因素产生的诱导应力场的分布状况,因而不能对重复压裂新裂缝产生的条件和最佳重复压裂时机、转向半径等进行定量描述。地应力场计算机模拟技术研究通过有限元数值模型,建立首次压裂后井筒附近由裂缝生成和油井生产引起的渗流场变化数学模型,进而预测地应力场的变化情况[1]。首次实现了对重复压裂地应力变化的定量分析研究,为重复压裂是否发生转向提供了较为可靠的依据。目前该项技术已在大庆、吉林及二连油田推广应用。
The previous research on field stress before refracturing was only its mechanism. There was no complete and systematical calculation model, which could describe quantitatively the distribution of induced stress field caused by vertically fractured wells before refracturing. And therefore there was no quantitative description to the new fractures generation after refracturing, the optimal time of refracturing and the turning radius. During a research on the computer simulation of stress field, we applied a finite-element numerical model to establishing another seepage-field variation numerical model. Those variations are generated by fractures and caused by oil-well production near wellbore after initial fracturing. And then, we predicted stress field changes. This research for the first time fulfills a quantitative analysis changed from a qualitative analysis for earth stress variation after refracturing; and it provides a more reasonable basis for refracturing whether occurs a reorientation or not. So far, the computer simulation has been applied to Daqing, Jilin and Erlian oilfields.
出处
《天然气技术》
2008年第1期37-38,40,共3页
NATURAL GAS TECHNOLOGY
关键词
重复压裂
应力场
裂缝转向
预测技术
Refracturing Stress field Fracture reorientation Prediction technology
