Composition and mode of occurrence of minerals in Late Permian coals from Zhenxiong County,northeastern Yunnan,China  

作　　者：Tian Li Shi-Feng Dai Jian-Hua Zou Sen Zhang He-Hing Tian Li-Xin Zhao 

机构地区：[1]Chongqing Key Laboratory of Exogenic Mineralization and Mine Environment,Chongqing Institute of Geology and Mineral Resources,Chongqing 400042,China [2]State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology,Beijing 100083,China [3]Chongqing Research Center of State Key Laboratory of Coal Resources and Safe Mining,Chongqing 400042,China

出　　处：《International Journal of Coal Science & Technology》2014年第1期13-22,共10页国际煤炭科学技术学报（英文）

基　　金：This research was supported by the National Key Basic Research and Development Program(No.2014CB238902);National Natural Science Foundation of China(Nos.41272182 and 40930420);the Program for Changjiang Scholars and Innovative Research Team in University.

摘　　要：Minerals in the Late Permian coals from the Niuchang-Yigu mining area,Zhenxiong County,northeastern Yunnan,China,were investigated using optical microscopy and low temperature ashing plus X-ray diffraction(LTA?XRD).The results showed that minerals in the coal LTAs are mainly quartz,kaolinite,chamosite,mixed-layer illite/smectite(I/S),pyrite,and calcite,with trace amounts of marcasite,dolomite,and bassanite.The authigenic quartz generally occurs in collodetrinite or as a filling in cleats or cell cavities.This silica was mainly derived from aqueous solutions produced by the weathering of basaltic rocks in the Kangdian Upland and from hydrothermal fluids.The presence of b-quartz paramorph grains in collodetrinite probably indicates that these grains were detrital and came from a volcanic ash.Clay minerals are generally embedded in collodetrinite and occur as cell-fillings.Pyrite occurs as framboidal,anhedral,and euhedral grains and a cell-filling.The coals are high in pyrite and the high pyrite content probably results from seawater invading during the stage of peat accumulation.Calcite generally occurs as vein-fillings,indicating an epigenetic origin.

关 键 词：Late Permian coals Minerals in coal Zhenxiong of Yunnan 

分 类 号：P61[天文地球—矿床学]