伊宁矿区北区西山窑组煤中稀土元素地球化学特征  

Geochemistry Characteristics of Rare Earth Elements in Xishanyao Formation Coal from North Yining Mining Area

作　　者：孟瑞艳[1,2] 毛礼鑫 朱士飞 秦云虎[1,2] 刘威 MENG Ruiyan;MAO Lixin;ZHU Shifei;QIN Yunhu;LIU Wei(Jiangsu Design Institute of Geology for Mineral Resources,Xuzhou,Jiangsu 221006;Key Laboratory of Mineral Resource in Coal Measures,CNACG,Xuzhou,Jiangsu 221006;Key Laboratory of Coalbed Methane Resources&Reservoir Formation Process,Ministry of Education,Xuzhou,Jiangsu 221008)

机构地区：[1]江苏地质矿产设计研究院,江苏徐州221006 [2]中国煤炭地质总局煤系矿产资源重点实验室,江苏徐州221006 [3]煤层气资源与成藏过程教育部重点实验室,江苏徐州221008

出　　处：《中国煤炭地质》2024年第9期26-31,43,共7页Coal Geology of China

基　　金：2023年度江苏省碳达峰碳中和科技创新专项(BE2023855);江苏省地质学会课题(JSDZXH-P2024-06);徐州市科技局科技专项(KC23073、KC23120);江苏地研院科技专项(JSY-2024-J01-1)。

摘　　要：煤中稀土元素具有重要的地质环境指示作用,也是潜在的稀土矿产接替资源。在伊宁矿区北区采集了西山窑组4个主采煤层的煤样进行了煤质与稀土元素地球化学测试分析。结果表明,西山窑组煤具有低灰、低硫、高挥发分、高发热量的特点,煤灰组分以Si、Al、Ca、Mg氧化物为主;煤中稀土元素含量为4.48~36.52µg/g,低于煤层顶板(36.68~191.35µg/g),其中7^(#)、6^(-2#)煤中稀土元素含量较低,为平坦型,具有Ce负异常;6^(-1#)、5^(#)煤中稀土元素含量较高,为左倾型,具有Ce轻微负异常、δEu略小于1的特点;煤中稀土元素与中酸性岩浆岩有关,以黏土矿物吸附的形式赋存。综合分析认为西山窑组沉积时期气候干热、以氧化环境为主,水深由7^(#)煤层到5^(#)煤层变浅,陆源碎屑对煤层成分影响较大。Rare earth elements(REEs)in coal play significant roles in geological and environmental indications,and can also serve as a substitute for rare earth resources.Coal samples from four main coal seams of Xishanjiang Formation were collected in the north of Yining mine for coal quality and REEs geochemistry.The results indicate that Xishanyao Formation is characterized by low ash,low sulfur,high volatile matter,and high heat value.The ash component is mainly composed of Si,Al,Ca,and Mg oxides.The REEs content in coal ranges from 4.48µg/g to 36.52µg/g,which is lower than the top of the coal seam(36.68µg/g to 191.35µg/g).Coal seams 7^(#) and 6^(-2#) have low REEs content with a flat type distribution showing a negative Ce anomaly.On the other hand,coal seams 6^(-1#) and 5^(#) exhibit high REEs content with a left-leaning type distribution showing a slight negative Ce anomaly andδEu slightly less than 1.The presence of REEs in coal is related to intermediate-acidic igneous rocks and exists in the form of adsorption by clay minerals.It is concluded that during sedimentation period of Xishanyao Formation was dry and hot with an oxidizing environment,and from 7^(#) to 5^(#) depositional period,the water depth decreased and the influence of terrigenous debris on coal seam increased.

关 键 词：稀土元素 地球化学 沉积环境 伊北矿区 

分 类 号：P595[天文地球—地球化学] P618.11[天文地球—地质学]