涪陵地区页岩气易碎地层随钻识别研究

Study on Real-Time Identification of Fragile Strata While Drilling in Fuling Area

为了快速准确评价页岩气水平井随钻易碎地层,保障地质工程施工安全,通过对涪陵地区岩心实验分析和实钻井地质工程参数综合发现,易碎地层主要由裂缝发育程度控制,其随钻响应参数主要为钻时、随钻伽马、气测特征以及包含钻压、转速、扭矩组成的工程参数指标。基于多参数随钻识别模型研究认为,功指数模型能够快速有效识别裂缝发育井段和易碎地层段,与岩心观察描述资料和测井偶极资料解释成果具有一致性,应用效果较好,可为随钻易碎地层识别提供新的方法和思路。

In order to rapidly and accurately evaluate the fragile strata while drilling horizontal wells for shale gas in the Fuling area and ensure the safety of geological engineering operations,a comprehensive study was conducted on core experimental analysis and synthesis of geological engineering parameters during actual drilling.It was found that the fragile strata are mainly controlled by the degree of fracture development,and the main parameters of their response while drilling were determined.Based on a multi-parameter drilling recognition model,the Power Law Model was found to be able to effectively identify fractured intervals and brittle layers,with consistent results compared to core observations and dipole log interpretations.The application effect is good and it can provide new methods and ideas for real-time identification of fragile strata while drilling.