望儿山断裂中段矿床地质特征及成因

发布时间：2018-03-16 00:17

  本文选题：矿床成因　切入点：矿床地质特征　出处：《中国地质大学(北京)》2017年硕士论文　论文类型：学位论文

【摘要】：胶东半岛为我国最大的金矿成矿省。虽占全国国土面积的0.3%但却占有中国黄金全部储量的25%。地区内90%以上的金矿床均产于三(山岛)-仓(上)、招(远)-平(度)、焦家-新城等三条断裂带上。前人较为关注对焦家断裂等大断裂的研究,但对域内大型断裂的分支-次一级断裂(如侯家断裂、望儿山断裂等)的研究相对较少,而望儿山断裂为研究区内主要的控矿和容矿断裂。本文在总结前人在本地区的研究基础上,以望儿山断裂中段上庄和河东金矿为研究对象,对其地质特征:矿体特征、矿物特征和矿石特征以及构造控矿性质、硫同位素、流体包裹体、稀土元素特征和成矿时代等方面进行归纳分析进而总结望儿山断裂的矿床特征和控矿特征,探讨矿床成因。通过以上研究取得以下认识:1、断裂带内的矿体严格受到NNE向的构造控制,断裂的上下盘均有矿化蚀变和矿体产出,矿体多呈脉状产出且主断裂面附近的矿床大多平行于断裂面产出但矿体多产于下盘;断裂产状急剧变化处易于成矿,矿体具有等距分布的特点。2、河东和上庄的流体包裹体测定结果表明望儿山断裂中段的金矿床包裹体类型有液相包裹体、气液两相包裹体且这二种类型包裹体较为集中发育,成矿流体中成矿温度为210~330℃;成矿流体的盐度为4.06~12.86 wt.%NaCl;成矿压力43.51~76.48MPa,成矿深度5.28~7.26km,深部找矿潜力巨大。3、硫同位素和氢氧同位素研究表明断裂带上的矿床为壳幔混合岩浆热液成因,在矿床的演化形成过程当中幔源物质参与了成矿,在矿床形成的早期阶段以岩浆水为主,随着成矿的进行后期有大气降水的加入;在成矿时代上与郭家岭型花岗岩关系密切;矿区内的脉岩多与矿床共生或穿切矿床,可以很好的指示找矿。
[Abstract]:Jiaodong Peninsula is the largest gold mineralization province in China. Although it accounts for 0.3% of the country's national territory, it occupies 25% of the total gold reserves in China. Jiaojia-Xincheng and other three fault zones. Previous scholars have paid more attention to the study of large faults such as the Jiaojia fault. However, there are few studies on sub-primary faults (such as Houjia fault, Wangershan fault, etc.) of large-scale faults in the region. The Wangershan fault is the main ore-controlling and ore-bearing fault in the study area. On the basis of summarizing the previous studies in this area, this paper takes Shangzhuang and Hedong gold deposits in the middle section of the Wangershan fault as the research objects, and analyzes its geological characteristics: orebody characteristics. Mineral and ore characteristics as well as structural ore-controlling properties, sulfur isotopes, fluid inclusions, rare earth elements and metallogenic ages are summarized and the ore deposit characteristics and ore-controlling characteristics of Wangershan fault are summarized. The ore bodies in the fault zone are strictly controlled by the NNE direction structure, and there are mineralization alteration and orebody occurrence in the upper and lower face of the fault. The ore bodies are mostly vein shaped and the deposits near the main fault surface are mostly parallel to the fault surface, but the ore bodies mostly occur in the lower face, and where the fault occurrence changes sharply, the ore bodies are easy to be mineralized. The ore bodies have the characteristics of equidistant distribution. The results of fluid inclusions determination in Hedong and Shangzhuang show that the inclusions of the gold deposits in the middle section of Wangershan fault have liquid inclusions, gas-liquid two-phase inclusions, and these two types of inclusions are relatively concentrated. The ore-forming temperature of ore-forming fluid is 210 ~ 330 鈩，

本文编号：1617477