地应力预测方法在川南地区大寨页岩气田的应用

Application of Geo-Stress Prediction in the Dazhai Shale Gasfield of Southern Sichuan

针对川南大寨地区页岩气储层三维地应力预测的需求,建立基于横向各向同性介质的Suárez-Rivera地应力计算模型,进行三维空间地应力预测。计算结果表明:Suárez-Rivera横向各向同性介质地应力模型计算结果与单井地应力评价结果高度吻合,模型预测的最小水平主应力与压裂施工地层瞬时闭合压力一致,证实了该方法在川南大寨地区页岩地应力预测中的可靠性。该方法的成功应用,为川南地区页岩气地应力评价提供了理论支持,预测结果对后续页岩气的井位部署和压裂参数设计具有一定的指导意义。

In order to predict the 3D shale gas reservoir geo-stress in the Dazhai shale gasfield of Southern Sichuan, the Suarez-Rivera geo-stress calculation model based on lateral isotropy is established to predict 3D geo-stress. Calculation indicates that the calculation from the Suarez-Rivera geo-stress calculation model based on lateral isot- ropy is perfectly consistent with that of single-well geo-stress evaluation. The minimum horizontal principal stress predicted by this model is consistent with the instantaneous closing pressure during fracturing operation, which veri- fy the reliability of this method in shale geo-stress prediction in the Dazhai shale gas field of Southern Sicbuan. The successful application of this method could provider certain theoretical basis for the shale geo-stress evaluation in Southern Sichuan. The geo-stress prediction also can supply certain guidance for the subsequent shale gas well de- ployment and fracturing design.