东天山雅满苏铁矿床Re-Os同位素研究及其矿床成因指示

硫化物（如黄铁矿）的Re-Os同位素组成不仅可以对金属矿床进行年代学研究，还可以示踪成矿物质来源，是矿床学研究的一种重要手段。雅满苏铁矿床是东天山造山带最大的铁矿床，金属矿物主要为磁铁矿，其次为黄铁矿等硫化物，磁铁矿和硫化物是否同时形成，它们的流体来源是否一致并不清楚，严重制约了对矿床成因的准确认识。本申请拟在前人研究基础上，在详细的矿物学研究前提下，对该矿床不同成矿阶段的硫化物和磁铁矿进行Re-Os同位素研究，确定硫化物和磁铁矿的形成先后，进而确定该矿床是经历了一次还是多次成矿作用，厘定成矿时代与火山旋回的关系。利用不同成矿阶段硫化物的Re-Os同位素组成与硫化物的微量和稀土元素、硫同位素以及方解石的碳、氧同位素等的耦合关系，探讨成矿流体演化及成矿物质来源。该研究不仅对雅满苏铁矿床的成因认识具有重要意义，而且将拓展Re-Os同位素体系在示踪成矿物质来源方面的应用范围。

As an important study tool of the mineral deposits, Re-Os isotopes of sulfides such as pyrite not only can date the mineral deposits, but also trace the origin of ore-forming materials. The Yamansu deposit is the largest iron deposit in Eastern Tianshan. The metallic minerals of the deposits are mainly magnetite, and secondly sulfides such as pyrite. Whether magnetite and sulfides were formed at the same time and were derived from the same fluids are unknown, which results in insufficient interpretation of ore genesis. Based on previous studies, this proposal will carry out detailed mineral observation and Re-Os isotopic determination of sulfides and magnetite, in order to constrain the timing of these minerals, whether the deposit was formed by single or multiple geological events, and the relationship between mineralization and volcanic-eruptive cycles. By linking Re-Os isotopes of sulfides from different paragenetic stages with trace and rara earth elements, sulfur isotope of sulfides, and carbon-oxide isotopes of calcite, the evolution and origin of ore-forming fluids will be discussed. The study has important implications for the ore genesis of the Yamansu deposit and expanding application of Re-Os isotopes to reveal the origin of ore-forming fluids.