地质通报2025，Vol.44Issue(4)：633-648,16.DOI:10.12097/gbc.2024.07.001
内蒙古维拉斯托稀有金属-锡多金属矿床强还原性成矿斑岩特征及其对矿床成因的约束
Characteristics of strong reducing metallogenic porphyry and its constraints on the genesis of the rare metal-tin-polymetallic deposit in Weilasituo,Inner Mongolia
摘要
Abstract
[Objective]Since the discovery of the Weilasituo rare metal-tin-polymetallic deposit in Inner Mongolia,the genesis of its ore deposits has been a central focus of geological inquiry.Oxygen fugacity(fO2)has been identified as playing a pivotal role in the processes of tin element migration and enrichment.Accurate characterization of fO2in granites is essential for constraining the genesis of the Weilasituo tin polymetallic deposit.[Methods]This study employs LA-ICP-MS zircon U-Pb dating,whole-rock geochemical analyses,and zircon trace element studies to investigate granites closely associated with mineralization at the Weilasituo deposit.[Results]Zircon U-Pb dating reveals concentrated crystallization ages of the granites at approximately 120.2±1.6 Ma and 125.9±1.9 Ma,indicative of multiple magmatic episodes in this area.Zircon trace element analyses show that the Ce/Ce* average value for granites at Weilasituo is 400.87,with an average Eu/Eu* value of 0.062.Thelog fO2predominantly ranges from-26 to-20,and ΔFMQ values are concentrated between-6 and-1,suggesting a predominantly reducing ore-forming environment.The obtained age data closely align with previously proposed late-stage magmatic activity,indicating that these ore-forming magmas retained low fO2 characteristics.[Conclusions]In summary,it is concluded that oxygen fugacity is the key factor controlling the formation of Verastor deposit.The low oxygen fugacity of Verastor metallogenic magma inhibits the premature saturation of Sn in the deep crust,which enables Sn to accumulate in the magma and eventually form large-scale Sn mineralization.关键词
稀有金属/锡/氧逸度/锆石U-Pb定年/花岗岩/维拉斯托/内蒙古Key words
rare metal/tin/oxygen fugacity/zircon U-Pb dating/granite/Weilasituo/Inner Mongolia分类
地质学引用本文复制引用
杜立华,黄宇,高雄,牛兴国,郑国强,陈飞飞,曹晋东,赵丹,钟世华..内蒙古维拉斯托稀有金属-锡多金属矿床强还原性成矿斑岩特征及其对矿床成因的约束[J].地质通报,2025,44(4):633-648,16.基金项目
内蒙古自治区地质勘查基金项目《内蒙古自治区克什克腾旗大石砬子铅锌多金属矿预查》(编号:22-1-KC23)、国家自然科学青年基金项目《青海野马泉矿床成矿岩浆H2O和Cl含量精细研究:对矽卡岩矿床成因的约束》(批准号:42203066)和国家自然科学基金面上项目《基于多维数据的斑岩Cu矿床成矿岩浆机器学习识别方法和矿床成因研究》(批准号:42472104) （编号:22-1-KC23）
