【摘要】 准确预测地层孔隙压力是进行井壁稳定状态分析的基础,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。该模型是根据上部已钻井段的测井结果,对钻头下部未钻开地层的孔隙压力进行随钻预测,在实际运用中该方法与dc指数法和岩石强度法相比具有精确度较高,模型简单,计算方法简便等特点。通过实例计算证明了该方法的优越性,是一种比较理想的预测方法。更多还原

【Abstract】 The accuracy of predicting the formation pore pres- sure is the foundation of the wellbore stability analysis. Seismic data prediction before drilling is usually adopted in traditional prediction of formation pore pressure;howev- er,its accuracy can not meet the requirement of drilling operation.On the basis of the Grey Theory,a new meth- od of un-drilled formation under the bit is proposed,and then a grey model of formation pore pressure prediction while drilling is established.According to the drilling re- suits of the upper drilled section,prediction on the un- drilled formation pressure under the bit while drilling is carried out.Compared with dc index method and rock strength method,the grey model is characterized by high precision,simple design and easy calculation.The practi- cal application proves the modeling is a superior method on prediction.更多还原