熊耳山西缘康山金矿地球化学特征和矿床成因探讨

发布时间：2018-03-16 09:38

  本文选题：康山金矿　切入点：地球化学特征　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】：康山金矿位于华北地台南部熊耳山西缘,区内地层简单,太华群作为基底,熊耳群作为盖层,本文关键对康山金矿床变质岩、火山岩、蚀变岩和金矿石的主微量稀土特征进行系统研究分析,对控矿构造特征进行实地野外考察和构型解剖,对区域地质背景和矿区地质情况总结归纳,由点及面对熊耳山地区金矿成因进行了解和诠释。康山金矿区片麻岩具有富碱、富铝特点,原岩具有多源性,受到后期沉积作用和多期变质作用,主要原岩为火成岩和厚层泥岩。矿区火山岩主要为亚碱性,属于钾玄岩和高钾钙碱性系列的玄武安山岩,具有富铁、富镁、富碱和少铝的特征。从片麻岩-安山岩-蚀变岩-金矿石,SiO2质量分数逐渐升高,金的含量也随之增大。金矿石微量元素中,Rb、Ba、K富集、La、Ce、Nd、P、Zr、Hf、Y相对富集,亏损亲石元素Th、U和Ta、Nb、Sm、Ti、Lu,Sr、Nb和Ti强烈亏损。金矿石样品与蚀变岩以及赋矿地层安山岩的标准化分布曲线比较接近,矿石中V/Cr与Sr/Ba呈微弱正相关。太华群金的平均丰度为1.14×10-9,熊耳群平均值为0.64×10-9,从含金性来看,太华群提供成矿物质金的可能性稍大。康山样品稀土曲线都呈右倾型分布,均具有轻稀土微弱富集,重稀土微弱亏损的特点,蚀变岩分布曲线位于金矿石和围岩的过渡区间。金矿石轻重稀土大部分分异不太明显,其含量明显低于赋矿地层,倾斜角度与区内片麻岩和安山岩具有一致性,说明太华群和熊耳群都提供了一定的成矿物质,整体上,金矿石稀土特征值∑REE与LREE/HREE呈微弱正相关,LREE/HREE与δEu呈直线负相关关系,这与海相原岩沉积特征相符合。区内其构造控矿模式具有“一街五巷三层楼”特点,一街指北东向的康山-七里坪断裂为主控矿断裂,五巷指与主控矿断裂平行的同次级断裂,三层楼指蚀变及其分带。矿脉的分布具有等间距性叠加分布的特征,其不同位置的矿脉的品位和厚度也分布极不均匀,矿化作用从北部-东部-西部-南部矿化程度依次增强,厚度和品位具有正相关关系,含矿热液成矿的规律,具有脉动特征。区内幔源太华群和熊耳群以及壳源岩浆提供Au、S、Pb等微量元素,沿着导矿通道运移上行,期间先后受岩浆水、大气降水的混合作用,直至断裂交汇部位富集下来,在成因上属于中(低温)岩浆期后热液金矿床。
[Abstract]:The Kangshan gold deposit is located in the west margin of Xiong er Mountain in the south of North China platform. The strata in the area are simple, Taihua Group is the basement and Xiong er Group is the caprock. In this paper, the metamorphic rocks and volcanic rocks of the Kangshan gold deposit are discussed. The main trace rare earth features of altered rocks and gold ores are systematically studied and analyzed. Field field investigation and structural anatomy of ore-controlling structural characteristics are carried out, and regional geological background and geological conditions in mining areas are summarized and summarized. The origin of gold deposits in Xiongershan area is understood and interpreted. The gneiss in Kangshan gold deposit area is characterized by alkali-rich, aluminum-rich, multisource, late sedimentation and multi-stage metamorphism. The main primary rocks are igneous rocks and thick mudstone. The volcanic rocks in the mine are mainly subalkaline and belong to kalmonite and high potassium calc-alkaline series Black Tortoise andesite, which are rich in iron and magnesium. From the mass fraction of gneiss, andesite, altered rock and gold ore, the content of gold increases with the increase of mass fraction of SiO2. The depletion of the lithophile elements Thu U and Tahln NbSm Sm Sm Ti Li Lun SrNb and Ti are strongly depleted. The distribution curves of the gold ore samples are close to those of altered rocks and ore-bearing strata andesite, the distribution curves of which are similar to those of the ore-bearing strata andesite. The average abundance of Taihua gold is 1.14 脳 10 ~ (-9) and the average value of Xiong ear group is 0.64 脳 10 ~ (-9). The distribution curve of altered rock is located in the transition zone between gold ore and surrounding rock. Most of the differentiation of rare earth elements in gold ore is not obvious, and its content is obviously lower than that of ore-bearing strata. The inclination angle is consistent with gneiss and andesite in the area, indicating that both Taihua Group and Xiong'er Group provide certain ore-forming materials. On the whole, the rare earth characteristic value 鈭，

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