新疆鄯善县阿奇山铅锌(铜)矿床地质地球化学与成因探讨

Geology,Geochemistry and Genesis of the Aqishan Pb-Zn( Cu) Deposit in Shanshan County,Xinjiang

新疆鄯善阿奇山铅锌(铜)矿位于东天山造山带西南缘。为探讨其矿床成因,在分析矿区地质特征的基础上,对矿体、矿石、典型矿物、蚀变分带及矽卡岩等进行了研究。结合成矿阶段划分、物质来源、同位素分析及小东山花岗斑岩锆石U-Pb定年数据,表明成矿与区内同源幔源岩浆作用及早石炭世雅满苏组矿源层关系密切,早石炭世花岗斑岩(331.5±2.0Ma)引起了雅满苏矿源层元素初始活化、局部富集,并提供了部分矿质,后期叠加了与小东山火山机构有关的受近东西向断裂构造控制的火山期后热液-交代充填成矿过程。综合上述信息,认为矿床受断裂构造控制,是与幔源岩浆岩有关的火山沉积-热液叠加改造型铅锌矿床。

The Aqishan Pb-Zn（Cu） deposit is located in the southwest margin of the East Tianshan orogenic belt. Based on the analysis of the geology of the deposit, the characteristics of orebodies, ores, typical minerals, alteration zonation and skarn were studied. In combination with the division of mineralization stages, analysis of the material source and isotopes and zircon U-Pb dating of the Xiaodongshan granitic porphyry,it is shown that the mineralization is closely related to the homogeneous mantle-derived magmatism in the Early Carboniferous Yamansu Formation and the Early Carboniferous granite porphyry （331.5 ± 2.0Ma）, which resulted in the initial activation and partial enrichment of elements in the Yamansu ore source, and provided part of the mineralization. Later, it was superposed by the late-volcanic hydrothermal-metasomatic mineralization process controlled by the EW faults structure associated with the Xiaodongshan volcano. These lines of information suggest that this deposit is of a reform type featured by volcanic-hydrothermal superposition transformed related to mantle-derived magmatic rocks controlled by faults.