Application Of Trace Elements In Coal Analysis Of Coal-forming Environment

In order to obtain the relationship between trace elements in coal and coal-forming environment,this paper focused on the main coal seams from the Donglin mine in Chongqing,Dabaoding mine in Sichuan and Mengtuo mine in Yunnan,and 51 coal samples and rock samples were collected?included 47 coal samples and 4 rock samples?,and concentrations and modes of occurrence of trace elements were analyzed by various methods.Finally,the relationship which trace elements in coal and coal-forming environment had been discussed,this could provide scientific basis for comprehensive utilization of coal resources and environmental protection.In this paper,geochemical analysis of major and minor elements?especially redox-sensitive elements?in the samples was performed,and selected geochemical indicators that were conducive to discriminating coal-forming environment.The results showed that the light-heavy-earth elements are significantly different in the Donglin,Dabaoding and Mengtuo Mine,and the distribution pattern of rare earth elements was basically the same as that of the upper crust of the continent.The REE in No.4 and No.6 coals of Donglin Mine mainly received the supply of terrigenous debris,and the REE in No.4 coal roof may be partially from the Kangdian ancient land,and the REE in the bottom of No.6 coal seam may be mainly affected by alkali supply of volcanic ash.The REE in No.15^-33 and No.18 coal of Dabaoding Mine may be mainly from the ancient land of southern Yangtze River,a small amount of which originates from Kangdian ancient land.The REE of Mengtuo Mine may be affected by acidic granites in sedimentary basins.The Donglin Mine in Chongqing may be a warm and humid climate environment in the early stage of coal formation.At the later stage of coal formation,the climate gradually became dry and hot.The formation of No.15^-33 and No.18 coal in the Dabaoding Mine in Sichuan Province under the climatic conditions of transition from warm wet to dry heat.The Mengtuo Mine had a relatively stable climatic environment,mainly due to temperature and humidity.Meng-tuo lignite was mainly deposited in oxygen-enriched water bodies.During the deposition of No.4 and No.6 coal in Donglin Mine,salt water occurred in sedimentary water,and this saltiness was caused by seawater intrusion.Dabaoding Mine No.15^-3and No.18 coal and Mengtuo lignite were deposited in a freshwater environment.