基于灰色理论的地层孔隙压力随钻预测

准确预测地层孔隙压力是进行钻井液密度选择和合理井身结构设计的基础,传统的地层孔隙压力预测通常采用钻前地震资料预测,其精度较低不能满足钻井施工的需要。文章以灰色理论为基础,提出了钻头下部未钻开地层的孔隙压力预测新方法,建立了地层孔隙压力随钻预测灰色模型群。该方法是根据上部已钻井段的随钻监测结果,对钻头下部未钻开地层的孔隙压力进行随钻预测。通过塔里木油田塔中722井的应用表明,改进新信息灰色模型预测结果较好,吻合度较高,能够满足现场施工的安全和技术要求,是一种值得推广的地层孔隙压力随钻预测方法。

Pore Pressure Prediction while Drilling Based on Grey Theory

The accurate predicting formation pore pressure is based for drilling fluid density choosing and casing programme designing,the precision of predicting the formation pressure by seismic data before drilling was relatively low in general,and it can't meet the requirement of actual drilling operation.According to the grey theory,a new method of pore pressure prediction for undrilled formation beneath the bit was offered in the thesis,and a grey model of formation pore pressure prediction while drilling was established.The undrilled formation beneath the bit was predicted while drilling according to the drilled formation up the bit.The application of Well Tazhong 722 indicated that the predicting result of the improved new information grey model is better and also has higher coincidence.The model is a good method of formation pore pressure prediction while drilling and it is worth popularizing,because it can meet the needs of the safety and drilling technology for field operation.