钻前井壁力学稳定性研究

钻井过程中井壁稳定与否，关系到能否实现安全、快速的钻进，同时又能够尽可能的减少对储集层段的污染，减少钻井费用，所以对井壁力学稳定性的研究越来越受到重视，已经成为当今乃至将来研究的重点。通过使用地震反演的方法，将测井资料作为反演的约束条件，构建待钻井处声波和密度测井曲线，利用测井的方法计算岩石力学特性参数，计算3个压力剖面，进而预测安全钻井液密度窗口，为钻井设计提供了参考，并可指导安全钻井。通过对高石梯潜伏构造上王家1井的安全钻井液密度窗口的预测与实钻钻井液密度和录井数据的对比分析表明，利用地震反演法钻前预测的安全钻井液密度窗口是准确的，具有工程应用价值。

PRE-SPUD STUDY ON MECHANICAL STABILITY OF WELLBORE

The wellbore stability during drilling is essential for safe and fast drilling, and it can minimize the contamination to reservoir and reduce drilling costs. So more and more attention is paid to the mechanical stability study of wellbore, which is the study focus of the present and the future. Through seismic inversion, using log data as the constraints, the sonic and density logs for formations to be drilled are constructed. And then the mechanical properties of the rocks are calculated, the 3 pressure profiles are calculated, the safe drilling fluid density margin is predicted, which will act as references for drilling design to guide safe drilling. Comparative analysis of predicted safe drilling fluid density margin, the actual drilling fluid density and logging data of Well Wangjia-1 at the submerged structure of Gaoshiti shows it is accurate that the safe drilling fluid density margin predicted by seismic inversion method, which has proved to be practical in real engineering.