Geochemistry Of Environmental Minerals And Associated Elements In Coal From Magmatic Intrusion Area From Wolonghu Coal Mine

China Eastern coalfields was widely intruded by magma.On the one hand,the coal seam structure,coal quality and utilization of coal were greatly influenced by magan;on the other hand,the hazardous trace elements were enriched in many minerals which impressed on the environment.Some coal and rock samples collected from magmatic intrusion area from Wolonghu coal mine in No.8 coal seam were determined by optical microscope,scanning electron microscope,X-ray diffraction,and a series of chemical experiments.Combining with the knowledge of mineralogy,environmental chemistry,mathematical statistics,responses of minerals and trace elements to igneous intrusion in the No.8 coal were investigated,and these results indicated as follows.(1)The coals displayed medium ash yields,extra low volatile matter,extra low water content and extra low sulfur.The intrusion of magma into coal seams resulted in the increase of ash yields and moisture,and the decrease of volatile matter;(2)The contents of quartz,ankerite and pyrite were gradually decreased for samples from intrusive rock,contact zone,to altered coal with silicon-rich hydrothermal,iron-rich hydrothermal and other factors;(3)Quartz,pyrite and carbonates in altered coal were mainly derived from magmatic hydrothermal fluids,kaolinite and illite were mainly from terrigenous deposit,and the chamosite was formed for metasomatism of kaolinite and iron-rich hydrothermal during early diagenesis;(4)The pyrite was formed with Fe in magmatic hydrothermal and coal seam and its crystalform was changed in altered coal;(5)The contents of Sc(7.09mg/kg),V(72.37mg/kg),Cr(18.35mg/kg),Cu(32.17mg/kg),Rb(14.29mg/kg),Cs(1.41mg/kg),Ba(200.68mg/kg)and Pb(20.28mg/kg)were higher than the average of Chinese coal;(6)V,Rb and Cs were mainly supported by clay minerals and were closely related to illite,Sc were mainly in clay minerals and pyrite,Cu and Pb were closely related to pyrite,and the occurrence of Cr and Ba in coal were closely related to the carbonates.