硫铅同位素研究进展及其在硫化物矿床中的应用

Research progress of sulfur and lead isotopes and their application in sulfide deposits

硫铅同位素示踪技术是地球化学研究领域中的一项重要内容。从离线分析到在线分析,从复杂的样品制备分析到原位微区分析,硫铅同位素示踪技术发展迅速,分析精度得到显著提升。通过梳理硫铅同位素的理论与技术研究进展,对比常用的热电离质谱(TIMS)、多接收电感耦合等离子体质谱(MC-ICP-MS)、二次离子质谱(SIMS)、激光剥蚀(多接收器)电感耦合等离子体质谱[LA-(MC)-ICP-MS]等检测技术的优缺点,并以那茶淌、百炉沟、乌斯河铅锌矿床为例,说明运用多种硫铅同位素分析技术组合来示踪矿床成矿物质来源具有较好的效果。LA-(MC)-ICP-MS不仅有可原位、实时、快速分析的优点,还具有高空间分辨率、高灵敏度、多元素及其同位素比值同时测定的优势,但仍存在基体效应和激光诱导分馏问题,期望更多基于硫铅同位素的研究推动其分析技术革新及成果应用。

Sulfur-lead isotope tracing technology is an important element in the field of geochemical research.From off-line analysis to on-line analysis,complex sample preparation analysis to in-situ microregion analysis,sulfur-lead isotope tracing technology has developed rapidly and the analytical accuracy has been significantly improved.By combing the theoretical and technical research progress of sulfur-lead isotopes,and comparing the advantages and disadvantages of commonly used techniques such as thermal ionization mass spectrometre(TIMS),multiply cups inductively coupled plasma mass spectrometry(MC-ICP-MS),secondary ion mass spectrometry(SIMS),laser ablation(multi-collector)inductively coupled plasma mass spectrometry[LA-(MC)-ICP-MS],etc.,and then taking Nachatang,Bailugou and Wusihe Pb-Zn deposits as examples to show that the combination of multiple sulfur-lead isotope analysis techniques to trace the source of ore-forming materials in the deposits is effective.LA-(MC)-ICP-MS not only has the advantages of in-situ,real-time,and rapid analysis,but also has the advantages of high spatial resolution,high sensitivity,and simultaneous determination of multiple elements and their isotopic ratios,but there are still problems of matrix effects and laser-induced fractionation,it is expected that more studies based on sulfur-lead isotopes will promote its analytical technology innovation and application of results.