摘要
李瑛萤石矿是位于大兴安岭南段的一座超大型脉状萤石矿床,矿体主要分布在上石炭统宝力高庙组火山岩中,受NW向断裂控制。该矿床前期主要工作集中于找矿勘查方面,矿床成因机制研究较为欠缺,制约了对下一步勘查工作的科学部署。文章结合区域萤石矿地质特征,开展了对李瑛萤石矿萤石中微量元素和稀土元素的研究,结果显示李瑛萤石矿微量元素均相对地壳富集U、Sr等元素明显,具同源性特征。稀土元素呈明显的重稀土元素富集特征,Y/Ho比值为24.95~42.03;La/Ho比值为0.24~7.81;δEu值为0.45~0.80(平均值为0.64),表现为中等Eu负异常;δCe值介于0.86~1.07(平均值为1.00)。La/Ho-Y/Ho、Tb/La-Tb/Ca对比关系分析均显示李瑛萤石矿为热液成因并受沉积地层改造,其成矿流体为同期同源的富F流体。与赋矿地层宝力高庙组和区域晚侏罗世花岗岩的地球化学特征区别明显,表明其萤石成矿与赋矿围岩和区域晚侏罗世花岗岩无直接关系。综合分析认为,李瑛萤石矿床属低温热液脉型矿床,成矿流体具有岩浆热液属性,F主要来自燕山期尤其早白垩世高度分异且浅部侵位的花岗质熔体,Ca则主要来自围岩。
The Liying fluorite deposit is a hydrothermal super-large vein-type fluorite deposit developed in the southern segment of the Great Khingan Mountains metallogenic belt.Its ore bodies primarily occur within the volcanic rock strata of the Upper Carboniferous Baoligaomiao Formation and are controlled by NW-trending faults.Previ‐ous work on this deposit mainly focused on prospecting and exploration,while research on its genetic mecha‐nisms remains relatively insufficient,constraining the scientific planning of further exploration.This paper pres‐ents a study on trace and rare earth elements(REE)in fluorite from the Liying deposit,integrating regional geo‐logical characteristics of fluorite mineralization.The results reveal that trace elements in Liying fluorite are rela‐tively enriched in U and Sr compared to the Earth’s crust,indicating a homologous origin.The REE distribution exhibits significant enrichment in heavy rare earth elements(HREE),with Y/Ho ratios ranging from 24.95 to 42.03 and La/Ho ratios from 0.24 to 7.81.TheδEu values vary between 0.45 and 0.80(average 0.64),showing moderate negative Eu anomalies,whileδCe values range from 0.86 to 1.07(average 1.00).Analyses of compara‐tive relationships—La/Ho vs.Y/Ho and Tb/La vs.Tb/Ca—consistently indicate that the Liying fluorite deposit is of hydrothermal origin and modified by sedimentary strata.Its ore-forming fluids were contemporaneous F-rich fluids derived from the same source.Distinct geochemical differences from the host Baoligaomiao Formation and regional Late Jurassic granites suggest no direct genetic link between fluorite mineralization and either the host rocks or regional Late Jurassic granites.Comprehensive analysis indicates that the Liying fluorite deposit belongs to the low-temperature hydrothermal vein-type.The ore-forming fluids exhibit magmatic-hydrothermal attributes,with fluorine primarily sourced from highly differentiated,shallowly emplaced granitic melts during the Yansha‐nian period(especially the Early Cretaceous),while calcium was mainly extracted from surrounding rocks.
作者
马玉波
王小慧
刘亚辉
闫秀文
张勇
MA YuBo;WANG XiaoHui;LIU YaHui;YAN XiuWen;ZHANG Yong(MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,CAGS,Beijing 100037,China;Xilin Gol League Longxing Mining Co.,Ltd.,Xilin Gol 026000,Inner Mongolia,China)
出处
《矿床地质》
北大核心
2025年第5期1001-1017,共17页
Mineral Deposits
基金
锡林郭勒盟隆兴矿业有限责任公司科技合作项目“阿巴嘎旗巴彦图嘎三队李瑛萤石矿矿床成因研究”(编号:HE2501)
地质调查项目“辽东—吉南成矿带战略性矿产调查”(编号:DD20242072)联合资助。
关键词
稀土-微量元素
矿床成因
中低温-酸性-弱还原流体
内蒙古自治区
锡林郭勒盟
阿巴嘎旗
李瑛萤石矿
rare earth and trace elements
genesis of ore deposit
medium-low temperature-acidic-weakly re‐ducing fluid
Inner Mongolia autonomous region
Xilin Gol League
Abag Banner
Liying fluorite deposit
