Geochemistry of trace elements and rare earth elements of coal in Chenjiashan coal mine

The trace elements and rare earth elements of No.4^# coal seam of mid-lower Jurassic Yanan Formation in Chenjiashan coal mine are analyzed in this paper.It is found out that the concentrations of W,Mo,Bi,Sn,Ba,Sr and Li are higher.It is indicated that the source rocks of Jurassic coal measures in Chenjiashan coalfield are acid rocks such as granite and gneissic granite.The mean value of rare earth element(REE) in No.4#coal seam is as much as 98.2×10^-6.The chondrite-normalized distribution patterns of REE in No.4^# coal are very similar and they are smooth curves like “V”,and the negative abnormal of Eu is apparent which indicates that the REE is closely related to terrigenous clastic rocks and during the deposition of No.4^# coal seam the terrigenous material derived from relatively acid rocks deposited in a stable condition.