三江中段夏塞银铅锌矿床微量元素富集机制及对成矿过程的指示：硫化物微区分析

项目名称： 三江中段夏塞银铅锌矿床微量元素富集机制及对成矿过程的指示：硫化物微区分析

项目编号： No.41202054

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 李艳军

作者单位： 中国地质大学（武汉）

项目金额： 25万元

中文摘要： LA-ICPMS原位微区分析能精确测定硫化物微量元素含量，为元素的赋存状态和富集机制研究提供微区证据。夏塞银铅锌矿床为三江成矿带中段与早白垩世晚期花岗岩体有关的热液脉型矿床，硫化物富集Cd、In、Sb、Bi等微量元素。本申请拟在全面野外基础地质、室内岩相学、矿相学和硫化物SEM-EDS形貌特征研究基础上，采用EPMA和LA-ICPMS原位微区技术对主成矿期S2-S4三个成矿阶段不同空间部位典型硫化物组合开展精确微量元素测试。结合矿床地质特征、Re-Os同位素年代学、流体包裹体温压及气液相成分、H-O, B, S, He-Ar, Sr-Nd-Pb-Hf等多元同位素示踪，阐明微量元素赋存状态、富集机制及对成矿过程的指示，刻画微量元素在成矿过程中的精细地球化学过程。对比分析VMS型、MVT型、Sedex型、矽卡岩型铅锌矿床微量元素组合及特征比值，建立热液脉型铅锌矿床成因宏观、微观综合判别指标。

中文关键词： 微量元素；硫化物；LA-ICPMS 微区分析；热液脉型银铅锌矿床；夏塞

英文摘要： The in situ laser-ablation inductively coupled mass spectroscopy (LA-ICPMS) can be used to precisely determine the concentrations of trace elements of sulfides, and provide containts for studying occurrence and enrichment mechanism of these elements. The Xiasai Ag-Pb-Zn deposit is in hydrothermal veins and related to the late Early Cretaceous granite, in central Sanjiang metallogenic belt, SW China. Some trace elements such as Cd, In, Sb, Bi are enriched in sulfides from the Xiasai deposit. In this proposal, based on systematic field work for geology of the Xiasai Ag-Pb-Zn deposit and analysis of thin and polished sections of alterational rocks and ores, four mineralizational stages, Stage 1 to Stage 4, are recognized by our preliminary work. We will invegate the micro-morphology characteristics of main sulfides from different space using a Scanning electron microscope and Energy Dispersive Spectrometer (SEM-EDS). After these, an Electron probe micro-analyzer and LA-ICPMS are used to precisely determine the concentrations of trace elements of sulfides from the Stage 2 to Stage 4. Conbining with the geology of the Xiasai deposit, homogenization temperature, pressure and geochemistry of fluid inclusions, Re-Os age of arsenopyrites, H-O, B, S, He-Ar, and Sr-Nd-Pb-Hf isotopic geochemistry of ores and rocks, we try t

英文关键词： Trace elements；Sulfide；LA-ICPMS analysis；Hydrothermal Ag–Pb–Zn deposit；Xiasai