泥页岩的X射线衍射定向指数与理化性能及井壁稳定的关系

A Study on Relationship Between Orientation Index of Shales by X ray Diffraction and Physicochemical Properties and Well bore Stability

首次提出了泥页岩Ｘ射线衍射定向指数的测定方法，探讨了定向指数与矿物成分，定向指数与泥页岩理化性能（密度、回收率、膨胀率、阳离子交换容量等）的关系。并在定向指数的基础上，提出了综合指数的概念，然后以定向指数和综合指数为主要依据，对坍塌地层泥页岩进行了分类。这对于钻井工程上研究井壁稳定的机理，预防井壁失稳，具有重要的理论意义和实用价值。

This paper gives out a method for the determination of Orientation Index of shales by X ray diffraction. Meanwhile, the relations between orientation Index and mineral compositions and physicochemical properties (density, recovery percent, expansion percent, cation exchange capacity etc.) are discussed. A new concept Comprehensive Index of shales is introduced on the basis of Orientation Index of shales. Then, the shales of easy collapsing formations are classified into four types according to Orientation Index and Comprehensive Index of shales. This work has an important theoretical significance and applied value in oil drilling engineering for studying mechanism of wellbore stability and preventing collapse of wellbore.