湖南锡田云英岩-石英脉型钨锡矿的形成时代及其赋矿花岗岩锆石SHRIMP U-Pb定年  

Geochronology of the Greisen-Quartz-Vein Type Tungsten-Tin Deposit and Its Host Granite in Xitian,Hunan Province

作　　者：付建明[1] 程顺波[1] 卢友月[1] 伍式崇 马丽艳[1] 陈希清[1] 

机构地区：[1]中国地质调查局武汉地质调查中心,湖北武汉430205 [2]湖南省地质调查院株洲矿产地质调查所,湖南株州412007

出　　处：《地质与勘探》2012年第2期313-320,共8页Geology and Exploration

基　　金：中国地质调查局项目(1212010533307)资助

摘　　要：具超大型规模远景的湖南锡田钨锡多金属矿床是1999年开始的新一轮国土资源大调查的重大发现之一。矿床产于锡田复式花岗岩体与碳酸盐岩接触带及岩体内部。矿床类型主要为矽卡岩型,其次为破碎带蚀变岩型和云英岩-石英脉型。采用石英流体包裹体Rb-Sr法和锆石SHRIMP U-Pb法分别获得:云英岩-石英脉型钨锡矿形成年龄为153±12Ma(MSWD=0.80),其赋矿花岗岩形成年龄为147±3Ma(MSWD=0.90),加权平均年龄为147.0±3.5Ma(MSWD=0.23),两者在误差范围内一致;并进一步证实,锡田钨锡多金属矿的主成矿期是燕山早期。The Xitian, Hunan Province tungsten-tin polymetallic deposit is one of the newly-discovered ones during the new round exploration in the Nanling range,which possesses a great potential of W＋Sn resources. Its tungsten-tin ore bodies occur in the contact zones between complex granite and carbonaceous rock and interior of rock bodies. In addition to dominant mineralization of skarn, altered rock in fractures zone and greisen-quartz vein types also characterize the deposit, respectively. In this work, fluid inclusions Rb-Sr dating and zircon SHRIMP U-Pb dating were conducted to constrain the a- ges of the tungsten-tin greisen-quartz vein and its host granite in Xitian. The Rb-Sr isochron result shows greisen mineralization occurred at 153 ＋ 12Ma （MSWD = 0.80） , and zircon SHRIMP U-Pb dating indicates that host granite was formed at 147.0＋3.5 Ma（ M SWD =-0.23 ）. Both are consistent in the error range. This work further confirms that the Xitian tungsten-tin polymetallic deposit was formed primarily during the early Yanshanian epoch （ Jurassic -Cretaceous） as suggested by previous studies.

关 键 词：石英包裹体Rb—Sr法 锆石SHRIMP U—Pb法 成岩成矿时代 云英岩脉型钨锡矿 湖南锡田 

分 类 号：P618[天文地球—矿床学]