赣南大吉山花岗岩成岩与钨矿成矿年龄的研究  

New Dating of the Dajishan Granite and Related Tungsten Mineralization in Southern Jiangxi

作　　者：张文兰[1] 华仁民[1] 王汝成[1] 陈培荣[1] 李惠民[2] 

机构地区：[1]南京大学内生金属矿床成矿作用研究国家重点实验室,210093 [2]中国地质调查局天津地质矿产研究所,300170

出　　处：《地质学报》2006年第7期956-962,共7页Acta Geologica Sinica

基　　金：国家重点基础研究发展规划项目(编号1999CB403209);国家自然科学基金资助项目(编号40572057)的成果

摘　　要：大吉山是赣南著名的钨—铌钽矿床,多年以来,由于受测试技术的限制,对该矿床的成矿年龄以及与成矿有关的大吉山花岗岩的成岩年龄缺乏系统和精确的研究。本文利用单颗粒锆石U-Pb同位素方法对大吉山补体花岗岩(铌—钽矿体的母岩)进行了成岩年龄测定,获得其侵位年龄为151.7±1.6Ma;利用快中子活化法对大吉山钨矿主矿脉中的云母进行了40Ar/39Ar地质年龄测定,获得了大吉山钨矿主矿脉的成矿年龄为144Ma和147Ma。根据这套数据,结合钨矿主矿脉、铌钽矿化和大吉山主体、补体花岗岩的空间产状,对它们的形成顺序进行了讨论。大吉山的花岗岩成岩与钨矿成矿年龄数据表明,它们是华南燕山中期陆壳重熔型花岗岩岩浆活动及相关的中生代第二次大规模成矿作用的产物。The Dajishan tungsten deposit is in a well--known tungsten ore--forming district in China. Because of technology restriction, little work has been done on the ages of ore--forming and related granite in Dajishan for a long time. By means of the single--zircon U--Pb isotopic method, the intrusion age is reported in this paper, which is 151. 7± 1. 6 Ma for a patched granite body （the source granite for Nb--Ta）. And by the quick neutron mobilization method, an ^40Ar/^39Ar age of mica from the major ore vein is determined, yielding oreforming ages of 144 Ma and 147 Ma. Combining these age data with the occurrences of the main granite body, the patched body, the major ore veins and Nb--Ta mineralization, the paper discusses their formation orders and relationships. These data also show that the Dajishan granite and its related mineralizations belong to the result of magmatism in the middle Yanshanian stage and a part of the secondary large--scale mineralization in the Mesozoic.

关 键 词：大吉山钨矿 补体花岗岩 成矿年龄 成岩年龄 

分 类 号：P588.121[天文地球—岩石学] P597.3[天文地球—地质学]