【作者】 李勇；

【导师】 喻学惠；

【作者基本信息】 中国地质大学（北京） ， 宝石学， 2009， 硕士

【摘要】 北衙金多金属矿是与滇西新生代富碱斑岩有关的典型代表之一,一直是地学工作者们们研究的热点。本文重点通过对不同矿段不同类型矿床的地质特征、成因类型、空间分布特征的野外观察,以及流体包裹体、同位素地球化学的分析测试和综合研究,探讨该区不同类型金多金属矿床之间的内在成因联系,建立以富碱班岩为主导的成矿系列,成矿作用关系以及,并在此基础上建立斑岩-热液成矿模式,为在该区(特别是外围地区)进一步寻找同类型矿床提供理论基础和实际资料。研究表明:北衙地区包括了斑岩成矿系列和表生成矿系列两个系列矿床,其中斑岩成矿系列由矽卡岩型铁金矿,斑岩型铜金矿,爆破角砾岩型金多金属矿,热液脉型铁金多金属矿组成,这些矿床的矿体空间分布、控矿因素、围岩接触、矿石的结构构造、矿石的自然类型,、成矿地球化学特征以及含矿岩系组合等特征存在不同,但是都与富碱斑岩有关。对本区中脉石英和富碱斑岩中的流体进行分析,分析表明,本区存在3种流体,即高温高盐度流体、中高温高盐度流体、中低温低盐度流体。流体总体属于NaCl-H2O体系,均一温度范围在132～﹥550℃之间,盐度范围在1.9～61.1 w(NaCleq)%之间。单个包裹体的激光拉曼探针成分分析显示流体中富含Cu、Fe等成矿元素以及Cl、CO2、S等矿化剂。表明成矿流体与富碱斑岩分异有关。对矿石中的金属矿物黄铁矿、方铅矿、黄铜矿等S、Pb同位素进行测试,证明了成矿物质主要来源于深部。富碱斑岩岩浆在成矿过程中,不仅为含矿流体的上升提供了动力和热能,而且还是成矿物质和成矿流体的主要来源。通过对该区成矿模式的研究,认为万硐山、红泥塘矿段深部和炭窑-马头湾-南大坪一带具有寻找金多金属矿的良好潜力,能成为下一步勘探的重点地段。更多还原

【Abstract】 Beiya gold-polymetallic deposit is one of typical deposits related to alkali-rich intrusion of the Cenozoic in western Yunnan, so it has been a research focus to scholars for a few years. In order to discuss the relationship between mineralization and alkali-rich porphyries, and investigate genetic relation among various ore types, this article studies geologic features, spatial distribution, fluid inclusions, isotope geochemistry of Beiya deposit, and concentrates on the study on spatial distribution, extensive field investigation of different ore blocks. Besides, the source of the mineralization fluid and ore-forming materials is also studied . On the basis of this study, a metallogenetic model is proposed for Beiya gold-polymetallic deposit, which focuses on metallogenesis system related to alkali-rich intrusion, ultimately this model will manage to provide the scientific evidences and theoretical foundation for prospecting the same genetic type deposits in Beiya ( especially in the outlying area). Based on the above-mentioned research, the following conclusion is reached:On the basis of demand for classification of genetic types , we have developed detailed field investigations about various ore blocks, especially about the geological phenomena exposed by the new exploitation, and then integrated comprehensive analysis of the existing geological data and the results of previous studies. Based on the above-mentioned research, we categorize gold-polymetallic deposit in Beiya two metallogenic series, namely, porphyry and epigenetic metallogenic series in accordance with structure and natural type of ore, spatial distribution of ore bodies, metallogenic geochemistry characteristics, features and assemblage of ore-bearing strata. And it proposed a metallogenetic model for Beiya gold-polymetallic deposit.There exists 3 types of fluids, namely, the high temperature , high salinity fluids ; the medium-high temperature ,high salinity fluids; the medium-low , low salinity fluids. Researches show that the ore forming fluids are of NaCl-H2O types, the homogenization temperatures range from 132℃to﹥550℃, the salinities are in the range of 1.9～61.1 w(NaCleq)%. It shows that that the ore-forming fluids related to the alkali-rich porphyry differentiation.The S, Pb isotopic composition of pyrite, galena, chalcopyrite in ore suggests that in metallogenic process the alkali-rich porphyries in this area not only provide power and thermal energy, but also are main source for the mineralization resources and fluid resources.By the research in metallogenic model of the area, it suggests that the deep of Wandongshan and Hongnitang ,Tanyao,Matouwan,Nandaping have the good potential of polymetallic ore deposit更多还原