碲在钨矿床中的矿化特征及富集机制：以赣南盘古山大型钨矿床为例

As a typical scattered element, tellurium rarely forms an independent deposit. It is common in hydrothermal type gold deposits. However, in recent years, tellurium has been found to be enriched in some hydrothermal type tungsten deposits in South China in different degrees. At present, there is no full understanding of the occurrence type, spatial distribution and fine mineralogical characteristics of tellurium in tungsten deposits and the physicochemical conditions of its formation. The source and enrichment mechanism of tellurium need to be clarified. With the tellurium-rich Pangushan tungsten deposit as an example, this project tries to find out the geological characteristics, fine mineralogy and mineral-chemistry characteristics of tellurium occurrence by using the electronic probe and its wavelength dispersive mapping technique, scanning electron microscope, laser ablation inductively coupled plasma-mass spectrometry, and extracts the indicating information of the mineralization process based on the detailed field investigation and indoor mineralography research. At the same time, it analyzes the content of tellurium in different geological bodies in the mining area, and traces the source of tellurium and tellurium-carrying fluids based on S, H-O and He-Ar isotopic test of tellurium-rich and tellurium-poor ores. Then, it conducts a comparative study on the temperature and composition characteristics of the fluid inclusions of tellurium-rich and tellurium-poor ores, and limits the physicochemical conditions of telluride formation based on the mineral phase diagram to reveal the enrichment mechanism of tellurium. The research results have important scientific value for enriching the theory of symbiotic mineralization of tellurium and tungsten and important economic significance to guiding the discovery of tellurium in tungsten deposit in South China and the comprehensive utilization of the resources.

碲是一种典型的稀散元素，很少形成独立矿床，通常富集在热液型金矿床中。然而，近年来发现华南部分钨矿床不同程度富集碲化物，目前对这些碲化物的类型、空间分布、精细矿物学特征及形成物理化学条件尚缺乏充分认识，碲来源及富集机制有待阐明。本项目拟立足于富含碲化物的赣南盘古山钨矿床，在详细野外调研和矿相学研究基础上，应用电子探针及其波谱Mapping技术、扫描电镜和激光剥蚀等离子质谱分析，查明碲化物产出地质特征、精细矿物学和矿物化学特征，有效提取成矿指示信息；对矿区不同地质体开展碲含量分析，结合富碲矿石和贫碲矿石的S、H-O、He-Ar同位素测试，示踪碲及载碲流体的来源；对比研究富碲矿石和贫碲矿石的流体包裹体温度和成分特征，结合矿物相图限定碲化物形成的物理化学条件，揭示碲的富集机制。研究成果对丰富碲与钨共生成矿理论具有重要科学价值，对指导华南地区钨矿床中碲的发现及资源综合利用具有重要经济意义。

碲是一种典型的稀散元素，很少形成独立矿床，以往对金矿床中碲的赋存状态和富集机理已取得较深入认识，但对钨矿床中碲的成矿作用关注不多。华南产出一批富碲的钨矿床，碲在这些钨矿床中的富集机制是有待研究的重要科学问题。本项目选择富碲的赣南盘古山钨矿床作为解剖对象，通过系统的矿物学、岩石学和地球化学研究，主要取得以下3个方面进展：（1）查明了盘古山钨矿床中碲化物类型和空间分布。矿床碲化物有六种，主要富集在矿床的中下部，且向深部具有依次出现硫碲铋矿A、Baksanite、应硫碲铋矿、硫碲铋矿B、硫楚碲铋矿及辉碲铋矿的趋势，碲化物逐渐富Te贫Bi、S，多与黄铜矿、磁黄铁矿、Bi2S3-PbS矿物等伴生。（2）查明了碲化物形成的物理化学条件。碲化物形成的温度范围为 235 ℃～425 ℃，logf（Te2）为-11.0～-7.1， logf（S2）为-12.2～-9.39，碲化物随着温度的降低、f（S2）的降低、f（Te2）/ f（S2）相对增大而趋于富集，碲化物的空间分带性是随着成矿流体物化条件的变化导致Bi2S3-PbS矿物系列中Bi 被Pb 置换与S被Te 置换的结果。（3）对碲元素的来源有了新的认识。矿床具有成矿多期次、多源性特征，且碲与钨的来源可能不同，W主要来源于花岗岩，Te则可能由石英闪长玢岩和玄武玢岩提供。到目前为止，标注本项目资助的学术论文共7篇，其中第一资助5篇，第二资助2篇，国际SCI论文1篇，EI论文2篇，中文核心期刊论文4篇，开展过多次学术交流，培养2名硕士研究生，项目负责人获得国家重点研发计划青年科学家项目子课题资助。