燕辽成矿带东段新台门钼矿床的Re-Os同位素年龄及其地质意义  

Molybdenite Re-Os dating of Xintaimen molybdenum deposit in Yanshan-Liaoning metallogenic belt,North China

作　　者：张遵忠[1,2] 吴昌志[2,3] 顾连兴[1,2] 冯慧[1] 郑远川[1] 黄建华[3] 李晶[4] 孙亚莉[4] 

机构地区：[1]江苏省有色金属华东地质勘查局,江苏南京210007 [2]内生金属矿床成矿机制研究国家重点实验室,南京大学地球科学与工程学院,江苏南京210093 [3]新疆大学地质与勘查工程学院,新疆乌鲁木齐830046 [4]中国科学院广州地球化学研究所,广东广州510640

出　　处：《矿床地质》2009年第3期313-320,共8页Mineral Deposits

基　　金：国家重点基础研究发展计划项目(2006CB403501);国家自然科学基金项目(40872050;40872064)的联合资助

摘　　要：文章对新台门钼矿取自花岗斑岩含矿石英脉中的5件辉钼矿样品进行了Re-Os同位素分析,获得模式年龄介于(177±4)～(185±1)Ma之间,加权平均年龄为(183±3)Ma(2σ,MSWD=1.6),表明该矿床形成于早侏罗世。结合区域岩浆活动和成矿作用的年代学格架,作者认为燕辽成矿带,特别是辽西地区的早侏罗世成矿作用非常重要,其形成应与印支期末华北板块与南北两侧大陆聚合后的伸展作用有关。The Xintaimen molybdenum deposit is situated in eastern Yanshan-Liaoning metallogenic belt and the transitional zone between the western Liaoning depression and the Shanhaiguan-Beizhen uplift in North China. There are two ore types in the deposit： one is veinlet-dissemination type, and the other is fracture-filling type. As the former type ore possesses the dominant position, the authors consider that the deposit can be regarded as a porphyry type Mo deposit. Five molybdenite samples from the veinlet-dissemination type ore yielded Re-Os isotopic model ages ranging from （177 ± 4） Ma to （185 ± 1 ） Ma, and a weighted average age of （183±3） Ma a（2σ, MSWD= 1.6）. These data show that the porphyry type Mo mineralization occurred in Early Jurassic. According to chronological framework of regional magmatic activities and igneous mineralization, this paper holds that the Early Jurassic mineralization is very important in the Yanshan-Liaoning metallogenic belt, especially in western Liaoning area. The tectonic setting is supposed to be of an extensional process after continental collision between the North China plate and the Mongolia and Yangtze block in Late Indo-China epoch.

关 键 词：地球化学 RE-OS同位素测年 斑岩钼矿 早侏罗世 燕辽成矿带 

分 类 号：P618.65[天文地球—矿床学] P597.3[天文地球—地质学]