煤系锂及锂同位素研究进展  

Advances in research on lithium in coal-bearing strata and its isotopes

作　　者：张昀 魏迎春[1,2] 曹代勇[1,2] 李新 靳亮亮 董博 王鑫 ZHANG Yun;WEI Yingchun;CAO Daiyong;LI Xin;JIN Liangliang;DONG Bo;WANG Xin(College of Geoscience and Surveying Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China;State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)地球科学与测绘工程学院,北京100083 [2]中国矿业大学(北京)煤炭精细勘探与智能开发全国重点实验室,北京100083

出　　处：《煤田地质与勘探》2025年第4期106-118,共13页Coal Geology & Exploration

基　　金：国家自然科学基金项目(42472231,42372187);宁夏2023年地质事业发展专项项目(640000233000000011005)。

摘　　要：【意义】锂(Li)作为新兴产业的重要战略金属,因其同位素显著的质量分馏效应,Li同位素成为重要的地球化学示踪工具。近年来,煤系Li矿产已成为战略性金属矿产资源勘探的重点。研究煤系Li同位素的组成及变化有助于揭示Li的来源、迁移与富集过程,并为煤系Li矿产的勘探与开发提供理论依据。【进展】从煤系Li的基本特征、同位素组成特征及分馏机制、煤系Li测试方法与提取分离及Li同位素测试分析技术3个方面总结了煤系Li及其同位素的研究进展。(1) Li在地幔和地壳中广泛分布,具有强烈的流体活动性。(2) 2种天然稳定同位素(^(6)Li与^(7)Li)因扩散速率差异及相对质量差,表现出显著的分馏效应,成为关键的地球化学示踪工具。(3)我国煤系Li矿产主要分布于华北石炭-二叠纪和华南晚二叠世煤系中,Li元素主要赋存于次生黏土矿物中,富集过程受沉积成岩、微生物活动、构造作用、岩浆热液活动及地下水迁移等多种因素的共同影响。(4)煤系Li同位素的分馏主要受温度、风化作用、变质作用及次生黏土矿物生成等因素的影响。煤系样品Li含量的测定方法已较为成熟,高精度Li同位素测试技术为Li同位素的广泛应用提供了可能。MC-ICP-MS已初步应用于煤系Li同位素分馏机制的研究,但煤系样品原位微区Li同位素测试技术尚处于探索阶段。由于含煤地层中Li的赋存载体成分和结构复杂,迫切需要开发煤系Li同位素原位分析标准样品和建立测试标准。煤系Li资源分离与提取的关键在于浸出效率的提高和浸出液中Li的提纯、回收。【展望】当前研究存在对于煤系Li同位素分馏机制探索尚浅、测试方法可能存在质量歧视效应、缺乏原位分析标准样品和模拟实验验证等一些不足。提出煤系Li及其同位素的未来发展趋势,包括煤系Li运移的动态过程与富集机制、高精度Li同位素�[Significance] Lithium serves as a significant strategic metal in emerging industries,and lithium isotopes have become crucial geochemical tracers due to their pronounced mass-dependent fractionation effects.Therefore,lithium minerals in coal-bearing strata have emerged as a priority in recent exploration of strategic metallic mineral resources.Investigating the isotopic composition and variation of lithium in coal-bearing strata helps reveal the sources,migration,and enrichment process of lithium while also providing a theoretical basis for lithium exploration and exploitation in coal-bearing strata.[Advances] This study offers a summary of advances in research on lithium in coal-bearing strata and its isotopes from three aspects:(1) the general characteristics of lithium;(2) the isotopic composition and fractionation mechanisms of lithium,and(3) the test methods,extraction,and separation of lithium,as well as techniques for the tests and analysis of lithium isotopes.The results indicate that lithium is extensively distributed in the mantle and crust,exhibiting strong activity with fluids.Two stable natural isotopes of lithium(i.e.,6Li and 7Li) exhibit significant fractionation effects due to their differences in the diffusion rate and relative mass,establishing them as critical geochemical tracers.Lithium minerals in coal-bearing strata in China are primarily distributed in the Carboniferous to Permian strata in North China and the Late Permian strata in South China.Lithium element occurs principally in secondary clay minerals,with its enrichment jointly influenced by multiple factors like sedimentary diagenesis,microbial activity,tectonism,magmatic-hydrothermal activity,and groundwater migration.The isotopic fractionation of lithium in coalbearing strata is primarily affected by factors including temperature,weathering,metamorphism,and the formation of secondary clay minerals.The methods for determining lithium content in samples from coal-bearing strata have been relatively mature,and high-precision technique

关 键 词：锂 锂同位素 含煤地层 元素迁移 分馏机制 

分 类 号：P618[天文地球—矿床学] TD11[天文地球—地质学]