大井锡多金属矿床矿石矿物成分及时空演化

Ore Minerals in Dajing Tin-polymetallic Deposit, Inner Mongolia, and Their Temporal and Spatial Evolution

文章总结和划分了矿床的矿石类型、矿化阶段及其在空间上的分布 ;对不同阶段、不同地段和不同类型的黄铁矿类、毒砂、黄铜矿、闪锌矿、方铅矿和锡石等 6种主要矿石矿物进行了电子探针微区分析。结果显示 ,矿床中主要矿石矿物的化学成分明显受时间因素控制 ,尤其是黄铁矿类和锡石。毒砂、闪锌矿、黄铜矿和方铅矿等硫化物 ,更具空间上的分带性 ,总体上 ,老区东部—北区南部的矿物成分特征显示出其形成温度较高 ,可能是本区的重要矿化中心 。

In this paper, the types and distribution of ores and the stages of mineralization are summarized, the composition and evolution of different types of ore minerals in time and three-dimensional space are emphatically studied and, on such a basis, the influence of the physical chemistry of fluids upon the composition is pointed out. Six kinds of minerals, such as pyrites, arsenopyrite, sphalerite, galena and cassiterite from various metallogenic stages, ore blocks and ore types were analyzed by EMPA. The constituents of six ore minerals, especially those of pyrites and cassiterite, are obviously controlled by temporal factors. Sulfides such as arsenopyrite, sphalerite, chalcopyrite and galena show obvious spacial zoning. On the whole, it is inferred that the area between the eastern part of Laoqu (local) block and the southern part of North block might be an important mineralization center characterized by ore minerals formed at high temperature, and that South block and West block might have other centers.