摘要
黔西北铅锌成矿区是川滇黔接壤铅锌矿集区的重要组成部分,区内铅锌矿床具多层位赋矿、逆冲断-褶体系控矿以及空间上与峨眉山玄武岩密切相关等特征。但目前关于区内铅锌矿床成矿物质来源和矿床成因等方面的研究相对薄弱,仍存在较大争议。本文选取黔西北亮岩铅锌矿床为研究对象,通过对金属硫化物Pb同位素和成矿期方解石C-O-REE等分析来揭示黔西北地区碳酸盐岩容矿型铅锌矿床的成矿物质来源和矿床成因。方解石C–O同位素指示成矿流体中的碳主要来源于石炭系赋矿碳酸盐岩的溶解作用,另外还有少量沉积地层中有机质的贡献,氧可能主要由盆地热卤水和赋矿碳酸盐岩共同提供。而金属硫化物的Pb同位素和方解石的稀土元素组成则指示成矿流体中的成矿金属和稀土元素主要来源于中元古代昆阳群变质基底与石炭系赋矿碳酸盐岩的二元混合。综合亮岩铅锌矿床的地质与地球化学特征,本文认为其成因类型为逆冲断-褶体系控矿的MVT铅锌矿床。
The Northwestern Guizhou Pb-Zn metallogenic area is a significant part of the Sichuan-Yunnan-Guizhou Pb-Zn metallogenic province.Orebodies of Pb-Zn deposits in this area are hosted in multi-layers of strata,structurally constrained by the thrusting fault-fold system and close spatially related to the Permian Emeishan basalt.However,there are still some controversies on the source of the ore-forming materials and the genesis of those deposits because of relatively limited researches.In this study,taking the Liangyan Pb-Zn deposit in the Northwestern Guizhou as research object,we have carried out the Pb isotopic analysis of sulfide minerals and C-O isotopic analysis and REE elemental analysis of ore-stage calcites from the deposit,aiming to elucidate the source of ore-forming materials and the genesis of the carbonate-hosted lead-zinc deposit in the northwestern Guizhou.The C-O isotopic data of calcites indicate that the carbon of ore-forming fluids was predominantly sourced from the dissolution of the Carboniferous carbonate host rocks with a minor contribution from organic matter within the sedimentary sequences.The oxygen was possibly derived from the hot basinal brine and ore-hosting carbonate rocks.The Pb isotopes of sulfide minerals and the REE compositions of calcites suggest that the ore-forming metals and rare earth elements within the ore-forming fluids were mainly originated from the binary mixture of the Mesoproterozoic Kunyang Group metamorphic basement and the ore-hosting Carboniferous carbonate rock.Combined with geological and geochemical characteristics of the Liangyan Pb-Zn deposit,it is suggested that the Liangyan deposit belongs to a thrusting fault-fold system-controlled MVT Zn-Pb deposit.
作者
吴涛
黄智龙
何志威
陈军
向震中
吴海枝
孟中能
高柱
WU Tao;HUANG Zhilong;HE Zhiwei;CHEN Jun;XIANG Zhenzhong;WU Haizhi;MENG Zhongneng;GAO Zhu(College of Mining Engineering,Guizhou University of Engineering Science,Bijie Guizhou 551700,China;State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang Guizhou 550081,China;College ofEarth Sciences,Chengdu University of Technology,Chengdu Sichuan 610059,China;College of Resource and Environment Engineering,Guizhou University,Guiyang Guizhou 550025,China)
出处
《矿物学报》
北大核心
2025年第4期672-684,共13页
Acta Mineralogica Sinica
基金
贵州省自然科学基金(编号:黔科合基础-ZK[2023]477)
国家自然科学基金资助项目(编号:42202099)
贵州省教育厅项目资助(编号:黔教合KY字[2015]340)。
