山西晋城和阳泉地区太原组15号煤夹矸粘土矿物组合类型及成岩转化

The Assemblage Types of Clay Minerals and Diagenesis of the Claystone Partings of Coal 15#of Taiyuan Formation in Jincheng and Yangquan District of Shanxi Province

本文运用X射线衍射分析和X射线荧光分析等手段,对山西晋城和阳泉地区太原组15号煤粘土岩夹矸进行了矿物组成和化学组成的研究。结果表明山西晋城和阳泉地区15号煤粘土岩夹矸粘土矿物组合共分三种类型:地开石组合、地开石+铵伊利石组合以及铵伊利石+高岭石组合。根据MgO/Al_(2)O_(3)可以确定:地开石组合和地开石+铵伊利石组合沉积古环境为海陆过渡沉积环境,铵伊利石+高岭石组合沉积古环境为淡水沉积环境。地开石和铵伊利石均是在成岩作用过程中由高岭石转化而来。少量叶腊石、绿泥石和伊利石的出现与热液蚀变作用有关。

The mineral and chemical composition of the claystone partings of Coal 15#of Taiyuan Formation in Jincheng and Yangquan in Sahnxi province were studied with the method of X-ray diffraction and X-ray fluorescence analysis.The results indicated that there were three types of clay mineral assemblage including dickite assemblage,dickite+ammonium-illite assemblage and ammonium-illite+kaolinite assemblage.Based on MgO/Al_(2)O_(3),it was found that the sedimentary paleo-environment of the dickite and dickite+ammonium-illite was paralic sedimentation,while that of ammonium-illite+kaolinite assemblage was continental sedimentation.Dickite and ammonium-illite were both transformed from kaolinite in diagenesis.The few clay minerals including pyrophyllite,illite and chlorite were formed from hydrothermal alteration.