XRD patterns of kaolinic rocks in coal measure: different views on characteristics of XRD patterns of kaolinite-dickite mixed-layer mineral

The XRD patterns of kaolinic rocks in the coal measure are divided into three types according to the basal reflection intensity of the kaolinite in China.It is presented the morphological features of the three kinds of the XRD patterns.The reasons by which the differences are caused among the XRD patterns of the kaolinite are analyzed,and it is negated that the kaolinite of which the basal reflections are enhanced is regarded as kaolinite dickite mixed layer mineral.