新疆松湖铁矿特征和成因

发布时间：2018-06-23 16:08

  本文选题：矿床地质 + 矿床地球化学　； 参考：《中国地质大学(北京)》2015年硕士论文

【摘要】：松湖铁矿产在新疆西天山阿吾拉勒铁成矿带中,其矿石类型多样,成矿作用复杂,在该成矿带铁矿床中具有代表性。作者在前人研究的基础上,对松湖铁矿进行了矿区和矿床地质以及矿床地球化学研究,查明了蚀变和矿化特征,划分了矿石类型以及成矿期和成矿阶段,探讨了矿床形成过程,取得了一些有意义的成果和认识。野外调研和镜下观察表明,松湖铁矿主要赋存在下石炭统大哈拉军山组火山-沉积岩地层中。围岩主要有安山岩、英安岩、凝灰岩和凝灰质砂岩,主矿体与赋矿围岩呈不整合接触。铁矿石可分为矿浆、蚀变岩和热液脉三种类型。矿浆型矿石呈蜂窝状和条带状,蚀变岩型矿石呈浸染状和斑杂状,而热液脉型矿石呈细脉和网脉状。松湖铁矿区围岩蚀变发育,主要有绿泥石化、绿帘石化、阳起石化、磁铁矿化、黄铁矿化、钾长石化、硅化和方解石化。其中钾长石化呈面状分布,绿泥石化、绿帘石化、阳起石化和磁铁矿化呈带状分布,硅化和方解石化呈脉状分布,而黄铁矿化呈点状分布。根据相互穿插关系以及矿物组合和结构构造特征,可将松湖铁矿的成矿过程分为矿浆、火山热液和表生三个成矿期。其中矿浆期包括磁铁矿和黄铁矿两个成矿阶段,火山热液期包括钾长石-绿泥石-磁铁矿、阳起石-绿帘石-磁铁矿和石英-硫化物-碳酸盐三个成矿阶段。表生期只有风化改造一个成矿阶段。矿浆期成矿温度为500℃~700℃,而热液期成矿温度为400℃左右。从论文获得的资料来看,新疆松湖铁矿为矿浆-火山热液复合型铁矿床。矿浆型矿石是由岩浆熔离的矿浆冷却结晶形成的,蚀变岩型矿石是火山热液交代火山岩形成的,而热液脉型矿石是火山热液在裂隙中充填结晶形成的。
[Abstract]:Songhu iron ore in the Awulale iron metallogenic belt in western Tianshan, Xinjiang, has various ore types and complex metallogenic processes, and is representative in the iron ore deposit of this metallogenic belt. On the basis of previous studies, the authors studied the ore area, ore deposit geology and deposit geochemistry of Songhu Iron Mine, identified the alteration and mineralization characteristics, divided the ore types, metallogenic periods and metallogenic stages, and discussed the formation process of the deposits. Some meaningful achievements and understandings have been achieved. Field investigation and microscopic observation show that Songhu iron deposit mainly occurs in volcanic and sedimentary strata of Lower Carboniferous Daharayanshan formation. The main rock rocks are andesite, dolomite, tuff and tuffaceous sandstone, and the main orebody is in unconformity with ore-bearing surrounding rock. Iron ore can be divided into three types: slurry, altered rock and hydrothermal vein. The slurry ore is honeycombed and banded, the altered rock ore is dyed and spotted, while the hydrothermal vein type is veined and reticulated. The surrounding rock of Songhu iron ore area is altered and developed, mainly including green mud petrifaction, green curtain petrifaction, actinolite, magnetite, pyrite, potassium feldspar, silicification and calcite. The distribution of potassium feldspar is plane, green mud, green curtain, actinite and magnetite are zonal, silicification and calcite are veined, and pyrite is dot. According to the intercalation relationship, mineral assemblage and structural characteristics, the metallogenic process of Songhu Iron Mine can be divided into three metallogenic periods: slurry, volcanic hydrothermal solution and supergene. The magmatic stage includes two stages of magnetite and pyrite, and the volcanic hydrothermal period includes three metallogenic stages: potassium feldspar-chlorite-magnetite, actinolite-verdite-magnetite and quartz-sulphide-carbonate. There is only one metallogenic stage in the epigenetic stage. The ore-forming temperature of slurry stage is 500 鈩，

本文编号：2057689