【作者】 崔玉斌；

【导师】 叶荣； 赵元艺；

【作者基本信息】 中国地质大学(北京) ， 地质工程， 2012， 硕士

【摘要】 拉屋矿床位于西藏自治区当雄县境内，大地构造位冈底斯弧背断隆带即隆格尔-念青唐古拉复合古岛弧带。本论文在系统的野外地质调查、室内岩矿鉴定、锆石LA-ICP-MS U-Pb法测年、白云母Ar-Ar法测年、Re-Os同位素测年、主量与微量元素测试、H-O、C、S和Pb同位素、流体包裹体包裹体温度与盐度分析的基础上，研究其地质地球化学特征及其成因。研究表明：拉屋矿区主要矿石矿物为闪锌矿、方铅矿、黄铜矿、磁黄铁矿、黄铁矿等，伴生有铟矿物和自然Bi与Bi的硫化物矿物等。拉屋矿区白云母二长花岗岩为高钾过铝质钙碱性系列花岗岩，形成于175Ma，为S型花岗岩。拉屋矿区白云母二长花岗岩与矽卡岩型的矿石的稀土配分模式一致，说明铜铅锌多金属矿化燕山期白云二长花岗岩有着密切的关系，白云二长花岗岩的侵入提供了的成矿物质来源。拉屋铜铅锌多金属矿床的磁黄铁矿的Re-Os同位素测年结果为309±31Ma，表明拉屋矿区晚石炭世来姑期应该有一次火山喷流-热水沉积时期，形成了初始矿源层。拉屋矿床成矿物质应由喷流沉积作用形成的初始矿源层与白云母二长花岗岩两者共同提供。拉屋铜铅锌多金属矿的形成表现为多期次、多成因的特征，矿床的形成与来故期的热水喷流作用有关，石炭系来姑组地层为成矿提供了成矿物质，而燕山期白云二长花岗岩又为矿体的再次富集提供提供了热源和部分成矿物质来源。因此，拉屋矿床成因为喷流沉积-岩浆热液叠加改造型矿床。更多还原

【Abstract】 Lawu deposit is located in the Dangxiong County, Tibet, within theLonggeer-Nianqingtangula volcanic-magmatic arc district. Based on the systematicfield geological survey, indoor rock and ore appraisal, zircon LA-ICP-MS U-Pbdating、40Ar/39Ar dating and Re-Os dating, test of major and trace element, H-O, C,S and Pb isotopes, temperature and salinity of fluid inclusions, we illuminated thegeochemical characteristics and genesis of the ore-deposit.Ore mineralssphalerite,galena,chalcopyrite,pyrrhotite, pyrite and so on, associated with indium andbismuth minerals.The age of muscovite monzonitic granite, metallogenic rock is175Ma.Muscovite monzonitic granite is S-type granite. The distribution pattern of rare earthelements of muscovite monzonitic granite is similar with that of the ores, indicatingthat the Lawu copper-lead-zinc deposit belongs to a sedimentary exhalative Cu-Pb-Zndeposit superimposed by the Yanshanian magmatic hydrothermal activity.A187Re-187Os isochron of309±31Ma for samples of pyrrhotite from the LawuDistrict is obtained in this paper，proving that the Lawu deposit is considered togenerate in the Laigu Period of the Late Carboniferous, and form the Sedex geneticdeposit.The Lawu Cu-Pb-Zn polymetallic ore deposit displays multiphase andmulti-multiple genesis characteristics,which is related with hydrothermal sedexprocess in Laigu period.The mineralization material originated from the LaiguFormation of the Carboniferous System,while the heat energy for re-enrichment of themineralization material was provided by the Yanshannian muscovite monzoniticgranite which had contributed part of the mineralization material.Therefore,weconlude that the Lawu deposit is a Sedex-magmatic hydrothermal reworkedpllymetallic deposit.更多还原