黔北晚二叠世煤中稀土元素地球化学特征及沉积环境指示  

Geochemical Characteristics and Sedimentary Environment Indicators of Rare Earth Elements in Late Permian Coal in Northern Guizhou

作　　者：邹银洪 雷正均 ZOU Yinhong;LEI Zhengjun(No.142 team,Guizhou Coalfield Geology Bureau,Guiyang,Guizhou 550025)

机构地区：[1]贵州省煤田地质局一四二队,贵州贵阳550025

出　　处：《中国煤炭地质》2025年第2期54-61,共8页Coal Geology of China

基　　金：贵州省新一轮找矿突破战略行动项目资助(黔自然资函[2022]632号)。

摘　　要：运用X射线荧光光谱(XRF)和高分辨电感耦合等离子体质谱(ICP-MS)技术测定了黔北地区6个矿井主采煤层共计22个煤样中的主量元素和稀土元素,探讨了煤中稀土元素的地球化学特征及沉积环境。结果表明:研究区煤中REY质量浓度为111.04~1233.21μg/g,平均浓度为405.39μg/g,属于煤中稀土元素高度富集区,且以轻稀土富集为主;不同煤层、矿井煤中稀土元素配分曲线特征相似性揭示成煤期物源一致,物源供应相对稳定,同时Ce无异常,Eu呈负异常,Yb呈正异常特征反映煤中稀土元素受陆源控制;煤中稀土元素质量浓度与CaO、Na_(2)O和MnO_(2)呈较中等正相关,推测主要赋存于碳酸盐或是有机化合物中;灰成分指数与δCe/δEu值指示沉积环境主要以弱还原为主,Al_(2)O_(3)/TiO_(2)值与REY和(La/Yb)N的关系显示煤中稀土元素的来源主要为中性岩。Major and rare earth elements(REY)in 22 coal samples from six main mines in northern Guizhou were analyzed using X-ray fluorescence spectroscopy(XRF)and high-resolution inductively coupled plasma mass spectrometry(ICP-MS).The geochemical characteristics and sedimentary environmental of REY in coal and their implications for sedimentary environments were investigated.The results show that the REY content in the study area ranges from 111.04 to 1233.21μg/g,with an average of 405.39μg/g;classifying the region as enriched in REY,predominantly light rare earth elements(LREY);similar distribution patterns of REY across different coal seams and mine suggest consistent provenance during coal formation,and stable material supply.The absence of Ce anomalies,presence of negative Eu anomalies,and positive Yb anomalies reflect terrestrial control on REY accumulation.A moderate positive correlation between REY concentrations and CaO,Na_(2)O,and MnO_(2)indicates possible associations with carbonates or organic compounds.The ash composition index(Al_(2)O_(3)/TiO_(2))andδCe/δEu ratios suggest a weakly reduced sedimentary environment,while REY distribution patterns and(La/Yb)N values indicate neutral igneous rocks as the primary source of rare earth elements.

关 键 词：煤 稀土元素 地球化学 沉积环境 

分 类 号：P618.11[天文地球—矿床学]