内蒙古浩布高铅锌多金属矿床两种花岗岩地球化学特征及含矿性分析  

Geochemical characteristics and metallogenic prediction of 2 types of granite from the Haobugao lead-zinc polymetallic deposit in Inner Mongolia

作　　者：颜晓华 李进喜 李欢[4] 朱大鹏 谢一鸣 蒋永芳 Yan Xiaohua;Li Jinxi;Li Huan;Zhu Dapeng;Xie Yiming;Jiang Yongfang(Hunan Geosun Hi-technology Co.,Ltd.;Hunan Provincial Deep Resource Electromagnetic Exploration Engineering Technology Research Center;The First Geological Exploration Institute,Bureau of Geology and Mineral Exploration and Development of Henan;School of Geosciences and Info-physics,Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring,Ministry of Education,Central South University;Bayerisches Geoinstitut,University of Bayreuth)

机构地区：[1]湖南继善高科技有限公司 [2]湖南省深地资源电磁法勘探工程技术研究中心 [3]河南省地质矿产勘查开发局第一地质勘查院 [4]中南大学地球科学与信息物理学院,中南大学有色金属成矿预测与地质环境监测教育部重点实验室 [5]拜罗伊特大学巴伐利亚地质研究所

出　　处：《黄金》2025年第2期72-82,共11页Gold

基　　金：国家自然科学基金重大研究计划资助项目(92162103);湖南省科技创新计划(2021RC4055,2022RC1182);湖南省自然科学基金项目(2022JJ30699,2023JJ10064)。

摘　　要：浩布高铅锌多金属矿床的矿床规模达到大型,与成矿有关的侵入岩主要是乌兰坝岩体,该岩体主要由二长花岗岩和石英二长岩组成。为研究乌兰坝岩体成因及其与成矿的相关性,分别对该两类岩石的主量元素、微量元素(包括稀土元素)进行了分析。结果显示:二长花岗岩和石英二长岩的SiO_(2)平均质量分数分别为73.85%、66.94%,均具高钾(w(K_(2)O)=4.48%、5.72%)、富铝(w(Al_(2)O_(3))=12.59%、15.10%)特征,前者为高钾钙碱性岩类,后者为钾玄岩系列岩类,岩石分异指数(DI)分别为90.27~93.07及83.94~90.55。二者稀土元素球粒陨石标准化配分模式均符合A型花岗岩特征,富集大离子亲石元素、亏损高场强元素。石英二长岩具有更高的稀土元素含量,同时显示出较弱的Eu负异常(δEu=0.70~0.96);二长花岗岩的Eu负异常较强(δEu=0.38~0.56),同时具有较低的La、Ce、Nd、Sm、Y、Yb、Lu等元素含量。二长花岗岩属于A1型花岗岩,而石英二长岩属于A2型花岗岩。结合区域地质背景,认为乌兰坝岩体形成于古太平洋板块向华北板块俯冲方向转变时期,区域伸展引起地幔物质的上涌和大量花岗岩浆的上升侵位,两种花岗岩主量元素、微量元素的差异与地幔物质的混入程度有直接关系。岩体变异系数和成矿系数的差异表明,二长花岗岩为主岩浆成矿期的产物,对Cu、Mo、Pb、W、Zn、Ag及Sn成矿有贡献;而石英二长岩促使了Cu、Bi、Ag和Sn的成矿。主成矿期及岩浆岩的确定对指导深部找矿和厘定矿床成因起到关键作用,同时也为区域花岗质岩体成矿潜力的判断提供了重要依据。The Haobugao lead-zinc polymetallic deposit is classified as a large⁃scale deposit,with the intrusive rocks closely associated with mineralization being the Ulanba rock mass,which primarily comprises monzogranite and quartz monzonite.To investigate the genesis of the rock mass and its relation to mineralization,major and trace ele⁃ments(including rare earth elements)of the 2 rock types were analyzed.Results show that the SiO_(2)mass fractions of monzogranite and quartz monzonite average 73.85%and 66.94%,respectively.Both exhibit high potassium(w(K_(2)O)=4.48%,5.72%)and rich aluminum(w(Al_(2)O_(3))=12.59%,15.10%)characteristics.Monzogranite belongs to alkaline rocks rich in K and Ca,whereas quartz monzonite corresponds to the shoshonite series.Their rock differentiation indi⁃ces(DI)range from 90.27-93.07 for monzogranite and 83.94-90.55 for quartz monzonite.The chondrite⁃normalized rare earth element(REE)patterns of both align with A⁃type granite features,enriched in large ion lithophile elements(LILEs)and depleted in high field strength elements(HFSEs).Quartz monzonite has higher REE contents and exhibits a weaker negative Eu anomaly(δEu=0.70-0.96)compared to monzogranite(δEu=0.38-0.56),which has lower La,Ce,Nd,Sm,Y,Yb,and Lu contents.Monzogranite is classified as A1⁃type granite,while quartz monzonite is categorized as A2⁃type granite.Based on the regional geological context,the Ulanba rock mass is interpreted to have formed during the transition of subduction direction of the Paleo-Pacific Plate beneath the North China Plate.Regional extension in the period triggered mantle upwelling and the emplacement due to granitic magma rising.Differences in major and trace elements between the 2 granites are directly linked to the degree of mantle material mixing.Variations in altera⁃tion coefficients and metallogenic factors suggest that monzogranite is associated with Cu,Mo,Pb,W,Zn,Ag,and Sn mineralization,while quartz monzonite contributed to Cu,Bi,Ag,and Sn mineralization.Determining the main mineral

关 键 词：浩布高 铅锌多金属矿床 二长花岗岩 石英二长岩 地球化学特征 含矿性 

分 类 号：TD11[矿业工程—矿山地质测量] P579[天文地球—矿物学]