【作者】 雎程晨；

【导师】 申俊峰；

【作者基本信息】 中国地质大学（北京） ， 矿物学、岩石学、矿床学， 2009， 硕士

【摘要】 毕力赫金矿地处华北板块北缘重要的金成矿带上,大地构造位置处于华北板块北缘叠接俯冲带南部近华北板块一侧。经前人工作,将毕力赫矿区圈定了5条矿化蚀变带,即Ⅰ矿带、Ⅱ矿带、26号矿脉、23号矿脉和22号矿脉,其中Ⅰ矿带于1998年投产出矿,目前资源接近枯竭。Ⅱ矿带为2007年武警黄金研究所新发现矿体,已提交储量约20吨。其它几个矿脉正在勘查之中。本论文在矿床地质特征野外调查基础上,通过手标本、显微镜观察和近红外光谱测量,重点进行了Ⅰ矿带五、六中段蚀变类型、蚀变空间分带及其与金矿化的关系研究;系统进行了Ⅰ矿带和Ⅱ矿带流体包裹体岩相学、均一温度和盐度的研究。综合矿区地质特征、蚀变特征以及流体包裹体特征,总结了矿区成矿特点,并就矿区近外围成矿潜力进行了探讨,得出结论如下:(1)赋矿围岩:Ⅰ矿带赋矿岩性主要为安山岩、花岗闪长玢岩、花岗斑岩,Ⅱ矿带赋矿围岩主要为次火山杂岩体(包括花岗闪长玢岩、二长花岗斑岩)和少量火山碎屑岩。其中次火山杂岩体的分布受北西向和北东向构造控制。(2)矿区围岩蚀变主要有绿泥石化、硅化、绢云母化、泥化、电气石化、碳酸盐化。其中绿泥石化主要分布在矿体外围,而硅化、绢云母化、泥化与金矿化关系密切,并呈线性沿构造带和岩体与地层接触带分布。其中,构造交汇部位和岩体与地层接触部位硅化、绢云母化、泥化等蚀变较为强烈。(3)Ⅰ矿带五、六中段流体包裹体研究结果表明:流体包裹体具有丰度高、个体小的特点,包裹体类型包括NaCl-H2O包裹体(纯气体、富气相和富液相)和含子晶的包裹体,其中以富液相NaCl-H2O包裹体为主。均一温度出现了三个峰值区,分别为220℃-280℃、160℃-220℃、120℃-160℃,表明主成矿阶段均一温度为160℃-220℃。盐度多<5%。这表明成矿流体具有低温低盐度特点。Ⅱ矿带流体包裹体测试结果与Ⅰ矿带一致。(4)综合矿区与金矿化关系密切的诸因素,推测22号矿脉和Ⅱ矿带南东部河沟处为金成矿有利部位。更多还原

【Abstract】 Bilihe gold mine lie in the north edge of Huabei tectonic plate. As an important gold mineralization area, it is in southern subduction zone closing to Huabei plate. From pervious works, five mineralization alteration zones were cycled in Bilihe mining zone: zone No.1 (exploited), zone No. 2 (new reserves found), No.26 vein, No.23 vein, and No.22 vein.Geological background of deposit of the mining zone have been investigated in detail. Rock samples from 201 mine body of zone No.1 were studied through microscope and Near-Infrared spectrometer to identify the types of alteration, spatial distribution, and the relationship with gold mineralization. Rock phase of fluid inclusion, homogeneous temperature, and salinity have been studied from zone No.1 and zone No.2. Considering with the results of Geological background, alteration character, and fluid inclusion, the mine forming characters and prospective mines have been discussed. Results are listed below:(1) Wall rock of mine body: Zone No.1 include andisite, granite-diorite-porphyrite, granite-porphyry; Zone No.2 include sub-volcanic rock (granite-diorite-porphyrite and monzonite-granite-porphyry) which is controlled by structure of north-west and north-east and minor volcanic clastic rock.(2)Alteration of wall rock in mining zone includes chloritization, silicification, sericitization, argillization, tourmalinization, and carbonatation. Chloritization happened around mine body, Silicification, sericitization, argillization are in the same places with gold mineralization in many areas,and distribute along structural zone and contact zone of stratum, and stratigraphic crossing and contacting layer between rock body and stratum have strong silicification, sericitization, argillization.(3) The study of high abundance and small size fluid inclusion from 5,6 middle parts of No.1 mining zone show that they are usually NaCl-H2O inclusion (gas phase inclusion and gas-fluid inclusion) and crystal inclusions. There are three peaks appearing in uniform temperature at 220 C-280 C, 160 C-220 C, and 120 C-160 C. It suggests that the mineralization temperature is 160-220 C, and salinity<5%. (4)Considering gold mineralization in the mine zone and Near-Infrared spectra data, the No.22 vein and south-east river of No.2 mine zone could be the prospective mine zone.更多还原