四川九寨沟葫芦沟金矿地质特征及其对成矿作用的指示  

Geological features of the Hulugou gold deposit in Jiuzhaigou of Sichuan Province and their indication for ore mineralization

作　　者：付琪智[1] 杨鹏飞 陈廷芳[1] 李世川 罗承 Fu Qizhi;Yang Pengfei;Chen Tingfang;Li Shichuan;Luo Cheng(School of Environment and Resource,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;Northwest Sichuan Geological Party,Sichuan Bureau of Geology &Mineral Resources,Mianyang 621000,Sichuan,China)

机构地区：[1]西南科技大学环境与资源学院,四川绵阳621010 [2]四川省地质矿产勘查开发局川西北地质队,四川绵阳621000

出　　处：《地质学刊》2018年第4期597-606,共10页Journal of Geology

基　　金："十二五"国家科技支撑计划项目(2011BAK12B02)

摘　　要：九寨沟葫芦沟金矿是川陕甘金成矿三角区典型的微细浸染型金矿床之一,矿体主要受断裂控制,赋存于中泥盆统三河口组三段上亚段灰岩(D_2s^(3-2))和下亚段板岩(D_2s^(3-1))中,容矿岩石以花岗斑岩为主,板岩次之,两者混合岩类少见。葫芦沟金矿床相关地球化学特征显示,构造-岩浆活动对成矿起了重要的控制作用,有深部流体参与成矿的迹象。富矿岩石板岩与花岗斑岩的主量、微量元素地球化学研究表明,矿石中Au、As、Ag、Hg、Cu、Fe、Zn、S、Sb等成矿元素极为富集,其形成的Au-(Fe+S)-Ag-Sb和As-Hg 2种元素组合,与矿床内黄铁矿、辉锑矿、毒砂等矿化特征极为吻合,反映它们与金成矿具紧密联系。研究表明:区内岩浆活动时代与金矿成矿时代相当,岩浆活动不仅为区内成矿提供热源动力,而且还提供了一部分颇为主要的成矿物质(岩浆水源和矿源);之后,浅成—超浅成花岗质酸性岩浆活化并萃取了矿源层中泥盆统三河口组(D_2s)中的Au,形成了含Au较高的成矿热液,在构造改造和多元含矿地热流体作用下,又以其能干性和化学活泼性等特点,为金矿的形成提供了良好的赋矿空间,直至演变形成葫芦沟金矿床。The Hulugou gold deposit in Jiuzhaigou is one of the typical micro-disseminated gold deposits in the Sichuan-Shaanxi-Gansu gold metallogenic triangle area. The ore bodies are mainly controlled by faults and occur in the upper sub-member limestone and lower sub-member slate of the third member of Middle Devonian Sanhekou Formation( D2 s3). The host rocks are mainly granite porphyry,followed by slate,and migmatites are rare. Geochemical characteristics of the Hulugou gold deposit indicate that tectono-magmatic activities play an important role in mineralization,and there may be signs of deep fluids involved in ore mineralization. Geochemical studies of major and trace elements of ore-rich slate and granite porphyry show that the ore-forming elements such as Au,As,Ag,Hg,Cu,Fe,Zn,S and Sb are extremely rich,and the Au-( Fe + S)-Ag-Sb and As-Hg element associations agree well with the mineralization characteristics of pyrite,stibnite and arsenopyrite in the deposit. It is suggested that these element associations are closely related to gold metallogeny. The above research shows that the age of magmatic activity in this area is similar to that of gold mineralization. Magmatic activity provides not only heat source power for the mineralization in this area,but also part of the main ore-forming materials( magmatic water source and ore source). Subsequently,the granitic acid magmatic activity in shallow and super shallow layers was activated and then extracted gold from source bed of the Middle Devonian Sanhekou Formation( D2 s) to form Au-rich metallogenic hydrothermal fluid. Under the action of tectonic reformation and multiple ore-bearing geothermal fluids,the hydrothermal fluid,characterized by its competence of mixing and chemical activity,provided good ore-hosting space until the formation of the Hulugou gold deposit.

关 键 词：地球化学特征 成矿作用 微细浸染型金矿 葫芦沟金矿床 四川九寨沟 

分 类 号：P618.51[天文地球—矿床学]