陈家山矿煤中微量元素和稀土元素地球化学特征

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

摘要: 通过对陈家山煤矿中下侏罗统延安组4^#主采煤层中微量元素和稀土元素的测试分析,发现煤中富集亲花岗岩的钨钼族元素W、Mo、Bi、Sn、Ba、Sr和Li,说明该区煤系形成期间的陆源碎屑主要来自花岗岩和花岗片麻岩等中、酸性岩石。4^#煤中ΣREE平均值为98.2×10^-6,稀土元素分布模式十分相似,呈左高右低的宽缓“V”型曲线,Eu负异常明显,反映出稀土元素与陆源碎屑岩关系密切,成煤期间稀土元素来源一致,陆源物质的供应相对稳定。

Abstract: 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.