安徽青阳高家塝钨钼矿床与狮金山钼铜多金属矿床的成岩成矿系统  

Magmatic-hydrothermal Metallogenic System of the Gaojiabang Tungsten-molybdenum Deposit and Shijinshan Molybdenum-copper Polymetallic Deposit,Qingyang County,Anhui Province

作　　者：徐晓春[1] 吴迪 傅仲阳 白茹玉[1,2] 许心悦[1] 宋朝晖 XU Xiaochun;WU Di;FU Zhongyang;BAI Ruyu;XU Xinyue;SONG Chaohui(School of Resources,Environmental Engineering,Hefei University of Technology,Hefei 230009,Anhui,China;Geological Survey of Anhui Province,Hefei 230001,Anhui,China)

机构地区：[1]合肥工业大学资源与环境工程学院,安徽合肥230009 [2]安徽省地质调查院,安徽合肥230001

出　　处：《大地构造与成矿学》2021年第3期492-508,共17页Geotectonica et Metallogenia

基　　金：国家自然科学基金项目(41472066);国家重点研发计划项目(2016YFC0600209)联合资助。

摘　　要：安徽青阳高家塝钨钼矿床和狮金山钼铜多金属矿床位于江南过渡带北段,均赋存于青阳‒九华复式花岗岩体北缘的花岗闪长斑岩侵入体中,两者在空间上紧密相邻,成矿元素组合分别为W-Mo和Cu-Pb-Zn-Au。本文在系统的野外地质调查和岩相学工作基础上,对两个矿床赋矿花岗闪长斑岩主量元素、微量元素、稀土元素和Sr-Nd同位素地球化学特征,以及矿石矿物S、Pb同位素组成特征进行分析,并厘定了狮金山矿床赋矿花岗闪长斑岩的LA-ICP-MS锆石U-Pb年龄和矿石中辉钼矿Re-Os年龄。研究显示,高家塝钨钼矿床和狮金山钼铜多金属矿床赋矿花岗闪长斑岩体地球化学特征相似,结合年代学研究,指示为同一期岩浆事件产物,成岩物质以壳源为主;矿石矿物S、Pb同位素组成特征指示两矿床受同一岩浆热液体系控制,其成矿物质主要来源于深部岩浆;成矿年龄与赋矿花岗闪长斑岩的成岩年龄显示,两个矿床成岩、成矿作用基本同时,且矿石类型、元素组合及其分带与岩体产状、岩体与围岩接触带及断裂构造关系密切,但流体包裹体均一温度明显不同,反映矿质富集和沉淀受控于地质及物理化学条件。由此推测,高家塝钨钼矿床和狮金山钼铜多金属矿床属于同一岩浆‒热液成岩成矿系统的产物,区内隐伏花岗闪长斑岩侵入体与相关围岩接触带部位是寻找此类钨钼铜多金属矿床的有利部位。The Gaojiabang W-Mo deposit and the Shijinshan Mo-Cu polymetallic deposit occur in the granodiorite porphyry intrusion at the north edge of the Qingyang-Jiuhua granitic batholith in the Jiangnan Transitional Belt.The two deposits show superimposed or transitional features of the Middle-Lower Yangtze Metallogenic Belt and the South Anhui Metallogenic Belt.Based on detailed field geological investigation and petrographic observation,the major and trace element compositions and Sr-Nd isotopes of the ore-bearing intrusive rocks and the S-Pb isotopic compositions of sulfides from the two deposits were determined,and the LA-ICP-MS zircon U-Pb age of the ore-bearing intrusive rocks and the molybdenite Re-Os isotopic age of the Shijinshan deposit were carried out.The results show that the ore-bearing granodiorite porphyries of the two deposits have almost the same geochemical characteristics and same zircon U-Pb ages,which means that the ore-bearing porphyries are coeval and originated from the same crust source.The two deposits have almost the same metallogenic ages which are in accordance with the U-Pb zircon ages of ore-bearing granodiorite porphyries.The S-Pb isotopic compositions of the sulfides imply the ore-forming material came from the magma.The ore types,element association and the zoning of the two deposits are closely related to the same intrusion.Thus,it may be inferred that the Gaojiabang W-Mo deposit and the Shijinshan Mo-Cu polymetallic deposit are products of the same magma-hydrothermal metallogenic system.

关 键 词：成岩成矿系统 矿床地质和地球化学特征 高家塝钨钼矿床 狮金山钼铜多金属矿床 江南过渡带 

分 类 号：P612[天文地球—矿床学]