赣南漂塘钨矿花岗岩成岩年龄与成矿年龄的精确测定  

New Dating of the Piaotang Granite and Related Tungsten Mineralizationin Southern Jiangxi

作　　者：张文兰[1] 华仁民[1] 王汝成[1] 李惠民[2] 屈文俊[3] 季建清[4] 

机构地区：[1]内生金属矿床成矿机制研究国家重点实验室,南京大学地球科学系,南京210093 [2]中国地质调查局天津地质矿产研究所,天津300170 [3]国家地质实验测试中心,北京100083 [4]北京大学造山带与地壳演化教育部重点实验室,100084

出　　处：《地质学报》2009年第5期659-670,共12页Acta Geologica Sinica

基　　金：国家重点基础研究发展计划(973)项目(编号2007CB411404);中国地质调查局重大项目(编号1212010632100);国家基金委重点项目(编号40730423)资助的成果。

摘　　要：漂塘钨矿是赣南著名的钨锡多金属矿床,由漂塘本区、木梓园和大龙山三个矿段组成。多年以来,有关漂塘花岗岩成岩年龄,大多是利用邻近的西华山花岗岩的数据进行推断,而已有的年龄测试数据精度很难保证。对该矿床的成矿年龄则报道更少。本文利用单颗粒锆石U-Pb法对漂塘本区和木梓园的成矿花岗岩进行定年,获得了两条很好的U-Pb年龄谐和线,漂塘本区和木梓园成矿花岗岩的年龄分别为161.8±1Ma和153.3±1.9Ma。利用矿石中的白云母40Ar/39Ar同位素定年获得了漂塘本区成矿年龄为152±1.9Ma,利用矿石中的辉钼矿Re-Os同位素定年获得木梓园成矿年龄为151.1±8.5Ma。以上年龄数据表明,矿床的成矿作用或与花岗岩侵位基本同时发生,或稍晚于花岗岩。赣南其他矿集区的一些代表性钨矿如淘锡坑、大吉山等的成矿与成岩也有这两种情况,可见这种成矿方式在赣南地区具有代表性。本文的年龄测定和近年来发表的一些年龄数据表明,赣南钨锡矿床属于华南燕山中期第一阶段陆壳重熔型花岗岩类大规模活动及其伴随的钨锡等金属大规模成矿作用的产物。The Piaotang tungsten deposit, a well- known tungsten -tin （Mo, Bi） polymetallic deposit in southern Jiangxi, China, consists of the Piaotang, Muziyuan and Dalongshan ore segments. Little work has been done on the ages of ore-formation and related granite in Piaotang. The intrusion ages of the Piaotang and Muziyuan granites are 161.8±1Ma and 153.3±1. 9Ma, respectively, using the single grain-zircon U-Pb isotopic method. The mineralized age of the Muziyuan ore segment is determined as 151.1±8.5 Ma （ N= 6,MSWD=11. 8） using the molyhdenite Re-Os isotopic method. A metallogenic age of 152± 1.9Ma for the Piaotang is obtained using the quick neutron mobilization 40Ar/39 Ar age method of mica from the major ore vein. All these age data indicate that the mineralization in this area occurred at the same time as or slightly later than that of granite intrusion. It is found that some representative tungsten deposits in southern Jiangxi such as the Taoxikeng and Daiishan present the similar characteristics in ages of mineralization and diagenesis. Therefore, this kind of mineralization is of great representative in southern Jiangxi. These are two common and representative cases for the granite-related tungsten-rare-metal deposits in southern Jiangxi such as the well-known Dajishan tungsten deposit and Taoxikeng tungsten deposit. Data by this study and the ages reported by previous research show that the tungsten-tin deposits in Southern Jiangxi Proviee are the results of large-scale granitic magmatism and the associated rare-metal minarelization in the middle Yanshanian period of the Mesozoic Era.

关 键 词：漂塘钨矿 单颗粒锆石U-PB年龄 辉钼矿RE-OS同位素年龄 白云母40Ar/39Ar法年龄 中生代大规模成矿 

分 类 号：P597.3[天文地球—地球化学]