【作者】 郎兴海；

【导师】 唐菊兴；

【作者基本信息】 成都理工大学 ， 矿产普查与勘探， 2007， 硕士

【摘要】 雄村铜金矿床和洞嘎金矿床位于西藏冈底斯构造带东段南缘。自晚侏罗纪以来，研究区先后经历了俯冲阶段、碰撞造山及陆内汇聚造山等构造动力作用，每次构造作用都在区内产生了各具特色的构造—岩浆活动，并伴随有强烈的成矿作用。因此，研究区内具有十分优越的成矿条件。本文以雄村铜金矿床和洞嘎金矿床为研究对象，通过对两矿床的矿区地质特征、矿体地质特征、矿床地球化学特征、矿床成因的阐述，进而对两矿床进行对比研究。通过两矿区地质特征的对比研究，认为两矿区的火山(沉积)—岩浆活动的时间和类型基本相同。在洞嘎矿区东部存在与雄村矿区类似的含矿斑岩体。通过对两矿床的矿体地质特征的对比，认为雄村铜金矿是一个层状(似层状)矿体，主要受地层岩性(凝灰岩)和斑岩体控制；洞嘎金矿是由脉状矿体组成的，主要受断裂—裂隙和地层岩性(凝灰岩)控制；两矿床矿体的矿石组构、矿石物质成分基本相同；雄村铜金矿具有典型的斑岩型矿床的热液蚀变类型和分带，与矿化有关的蚀变是黑云母化、钾长石化、红柱石次生石英岩化、硅化、白云母化，洞嘎矿区的热液蚀变较弱，分带不明显，与矿化有关的蚀变是硅化和围绕硅化的绢云岩化，硅化有时表现出玉髓—硫化物脉，具有浅成低温热液矿床的特征。通过对两矿床的常量元素、流体包裹体特征、同位素特征的对比研究，认为矿化凝灰岩和矿化斑岩岩均属钙碱性偏拉斑玄武岩火成岩系列；洞嘎矿床的流体包裹体特征与雄村矿区金矿化阶段的包裹体特征相似；两矿床的氢氧同位素组成特征相似，反映成矿流体来源于大气降水，但不排除岩浆水的参与；两矿床的硫同位素组成特征相似，反映深源硫的特征。通过对两矿床的成因研究认为雄村铜金矿床属斑岩型矿床，洞嘎金矿床属与斑岩成矿系统有关的浅成低温热液型矿床，两者同属斑岩—浅成低温热液成矿系统。更多还原

【Abstract】 The Xiongcun copper-gold deposit and the Dongga gold deposit are located in south of eastern Gangdisi tectonic belt.The region is experienced an evolution history including subduction orogeny of oceanic crust,collision orogeny and intra-continental orogeny since late Jurassic,every time,the tectonism produced its own tectonic-magmatic activities,and came along with mineralization.So,it will be very prospective to find more deposits in the region.This thesis takes Xiongcun copper-gold deposit and Dongga gold deposit as its research objects.Through analyzing the two deposits characteristics which include geological,orebody,geochemical and the genesis,the author carries out comparative research between two deposits.Through the contrast study of two deposits of geological characteristics,the author considers that the times and the types of volcanic (sedimentary)-magma activity in two deposits are similar;The author find mineralizational porphyry in the east of Dongga deposit.Through the comparative research of two deposits of orebody characteristics,the author considers that the Xiongcun deposit is a bed or like a bed orebody,which is controlled by stratum-lithology and porphyry,the Dongga deposit is to be composed of the veined orebody,which is controlled by the fracture-crack and stratum-lithology;the fabric and components of the ore in two deposits are same;the Xiongcun deposit has the typical porphyry deposit hydrothermal alteration and zonation,the alteration which is related to mineralization is demonstrated by biotite,K-feldspar,andalusite-secondary quartz,silicification,muscovite.The hydrothermal alteration of Dongga deposit is weaker,the alteration which is related to mineralization is demonstrated by silicification and quartz-sericite alteration around the silicification, the silicification occasionally shows as chalcedony-sulfide veins,the Dongga deposit shows the characteric of epithermal deposit.Through the comparative research of two deposits characteristics of macroelements,fluid inclusion characteristics, oxyhydrogen isotope, sulfur isotope,lead isotope,the author considers that the tuff and porphyry belongs to calc-alkalic to tholeiitic rock type;The inclusion characteristics of Dongga deposit are same as the inclusion characteristics of later period gold (silver)-Polymetallic mineraliztion of Xiongcun deposit;The oxyhydrogen isotope of the two deposits is similar,which shows the metallogenic fluid originating from atmosphere precipitation; The sulfur isotope of two deposits is similar,which reflects deep source sulfur characteristic.Through the genesis study of two deposits,the author considers that the Xiongcun deposit is a porphyry deposit, the Dongga deposit is a epithermal deposit, and the two deposits are belonged to porphyry-epithermal metallogenic system.更多还原