【作者】 王艳丽；

【导师】 彭齐鸣； 祝新友；

【作者基本信息】 中国地质大学（北京） ， 矿物学、岩石学、矿床学， 2014， 博士

【摘要】 南岭地区是我国重要有色金属产地，区内广泛分布大型、超大型钨矿。南岭花岗岩成岩及其与成矿的关系一直被学术界所关心。80年代以来，岩浆热液成矿理论研究取得重要进展，随着“岩浆-热液过渡阶段”观点的提出，岩浆-热液过渡性流体性质及成矿作用研究引起大家重视。以往主流观点认为石英脉型、矽卡岩型矿化为岩浆期后热液型，近年研究工作在湘东南地区与钨矿床有关的燕山期花岗岩岩株中发现大量岩浆液态不混溶地质现象，包括花岗岩型矿化、矿囊、云英岩析离体、碱交代脉、“眼球构造”、似伟晶岩（脉）等，其中一些不混溶地质现象中有明显岩浆→热液过渡性质表征，如析离体核部为热液结构，成分以石英和云母为主，边部为岩浆结构，具有花岗岩矿物组成；早阶段碱交代脉中间为花岗岩，两侧为钾长石-萤石脉等……以湘东南地区瑶岗仙、柿竹园、湘东钨矿为典型矿床，结合区内多个石英脉型及矽卡岩型钨多金属矿对比研究，通过详细的野外地质学、矿物学、地球化学等工作，针对高分异演化花岗岩晚期岩浆-热液过渡阶段花岗岩演化与成矿作用开展研究，取得以下新认识：1、发现一批具重要研究价值的代表岩浆晚期液态分异的地质现象。2、建立晚期花岗岩浆-热液连续演化过程，确定石英脉型、矽卡岩钨矿属于岩浆-热液型矿床。在云英岩析离体、碱交代脉、“眼球”状析出物等地质体中，广泛发育熔流包裹体，岩浆与热液之间存在浆液过渡态流体，岩浆→热液是连续演化过程，碱交代脉也有类似特点。3、建立岩浆-热液演化过程中成矿元素的迁移过程。岩浆液态分异过程中实现元素的迁移，以云英岩析离体为例，从碱长花岗岩I→析离体边部→核部，成矿元素W、Mo、Bi、Pb、Zn、Nb、Ta富集，挥发性元素Li、F富集，LREE/HREE减小，δEu亏损更加明显。各元素变化具有连续性，迁移方向也有所差异，W在析离体核部富集更明显，而Mo在析离体边部富集更强烈。4、初步建立石英脉型和矽卡岩型钨多金属矿岩浆-热液演化成矿模型，矿化严格受岩浆-热液演化过程的控制。脉型钨矿床中，岩浆岩型矿化形成于岩浆晚期分异的富挥发份岩浆；云英岩析离体形成于浆液过渡态流体；含钨石英脉多形成于高温热液阶段。矽卡岩型矿床中，早阶段碱交代脉具有浆液过渡态特点；晚阶段与早阶段碱交代脉渐变过渡，以热液流体为主，是成矿主要阶段。更多还原

【Abstract】 Nanling region is an important area of non-ferrous metal resources in China,which lots of large or very large tungsten deposits are widely distributed in the area.Diagenesis of the Nanling granite and the relationship between Nanling granite andtungsten deposits have always received attention from academic circle. Since the1980s, the magmatic-hydrothermal metallogenic theory (MHMT) has made importantprogress, and with the theory of MHMT putting forward, studies on the nature ofmagmatic-hydrothermal fluid and mineralization have gradually attracted thegeologists attention. The mainstream history view considered that quartz vein, skarnmineralization were post-magmatic hydrothermal type ore-forming mode. In recentyears, a large number of liquid immiscibility phenomena has found in Yanshan periodgranite strains which had a close relationship with the tungsten deposits in southeastHunan province, including granie-hosted tungsten mineralization, ore chamber,greisens segregations, alkali-metasomatized veins, eye-shape segregations andpegmatitoides, and so on. Some immiscible geological phenomenons recorded thefeatures of magmatic-hydrothermal evolution processes. For example, the core of agreisens segregation shows the textures in hydrothermal stages and it is comprisedmainly of quartz and mica, whereas the rim shows magmatic texture. And the centerof an alkali-metasomatized veins are granitic materials, while the margins are alwayscomprised of K-feldspar and fluorite veins.This thesis focuses on some typical tungsten ore deposits in southeast Hunan,including Yaogangxian, Shizhuyuan, Xiangdong and other quartz vein-type,skarn-type tungsten polymetallic deposits, and comparative study of the depositsmentioned above. Through detailed study of field geology, mineralogy, geochemistry,and so on, this thesis exponds the evolution of the high differentiation and evolvedgranite during the late stage of magmatic-hydrothermal transition and metallogenesis.The main results obtains in this paper are given in more detail below.1. A number of important geological phenomena which could represent the liquidimmiscibility of late-stage magma were found.2. The continuous evolution processes from granitic magmatic to hydrothermalwas constructed, and the quartz vein type and skarn type tungsten deposits belong tomagmatic-hydrothermal type deposits. In the magmatic-hydrothermal transition stage, some geological unites (e.g., greisen, greisen segregations,alkali-metasomatized veins and garnet skarns) widely host melt-fluid inclusions. Thestudies of fluid inclusions in greisen segregations and alkali-metasomatized veinsshows that the magmatic-hydrothermal evolution is a continuous process.3. The migration processes of ore-forming elements during the process ofmagmatic-hydrothermal evolution is recognized. Some elements can be concentratedduring the process of liquid immiscibility. Taking greisen segregations as example,from alkaline granite to margin and center of greisen segregations, the ore-formingelements (such as W, Mo,Bi, Pb, Zn, Nb and Ta), associated with volatile elements(Liand F) would be concentrated, meanwhile, the LREE/HREE ratios and δEu aredecreasing. The concentrations of each element are continuous and directional, forexample, W is much more concentrated in center, whereas Mo is much moreconcentrated in margin of the greisen segregations.4. The metallogenic models of both quartz-vein-type and skarn-type tungstenpolymetallic deposits are build. The tungsten mineralization is strictly controlled bythe processes of evolution from the magmatic to hydrothermal stage. As forquartz-vein-type tungsten deposit, the granitic-type ore was derived from volatile-richmagma which separated out at the late magmatic stage, the greisen segregations werederived from liquid at the magmatic-hydrothermal transition stage, and theore-bearing quartz veins were always formed at the high-temperature hydrothermalstage. As for the skarn-type deposit, the early alkali-metasomatized veins shows thecharacteristics of the magmatic-hydrothermal transition stage, which gradualtransformed to the late stage alkali-metasomatized veins. The fluid was hydrothermalin late stage alkali-metasomatized veins and this period is the main mineralizationstage.更多还原