广西中部大明山钨矿白云母^(40)Ar/^(39)Ar定年及其地质意义  

Muscovite ^(40)Ar/^(39)Ar age of the Damingshan tungsten deposit in central Guangxi and its geological significance

作　　者：杨锋[1] 冯佐海[1] 康志强[1] 肖荣 

机构地区：[1]桂林理工大学地球科学学院／广西地质工程中心重点实验室,广西桂林541004 [2]湖南省地质调查院．湖南长沙410116

出　　处：《地质通报》2011年第9期1429-1433,共5页Geological Bulletin of China

基　　金：国家自然科学基金项目《桂东中生代花岗岩体构造样式与内生金属成矿关系研究》(批准号:40772126);广西自然科学基金重点项目《广西中生代钨锡稀有金属矿床成矿规律及深部找矿预测》(编号:2010GXNSFD013001);广西壮族自治区教育厅项目《桂东中生代花岗岩与有色金属成矿规律研究》(编号:201010LX170)

摘　　要：大明山钨矿床是一个与岩浆活动有关的多金属矿床。为确定钨矿床的成矿时代,对钨矿床中的白云母进行40Ar/39Ar快中子活化测年,获得白云母坪年龄为(97.10±0.86)Ma,相应的等时线年龄和反等时线年龄分别为(96.6±1.7)Ma和(96.5±1.1)Ma。结果表明,钨矿矿化年龄为97Ma,为燕山晚期本区成岩成矿活动的产物。该成果为进一步认识大明山钨矿的成因机制和成矿动力学背景提供了新的年代学证据。Damingshan is an important area of tungsten metal resources in southern China.The Damingshan tungsten deposit was tied up with the Yanshanian magmatism activity.Samples of tungsten veins and muscovite were determined by 40Ar/39Ar fast neutron activation techniques.The plateau age of muscovite is 97.10±0.86 Ma,with normal and inverse isochron ages being 96.6±1.7Ma and 96.5±1.1 Ma.The age of the sample is reliable.According to the results of the 40Ar/39Ar dating,the time limit of tungsten mineralization should be 97Ma,which indicates that the ore-forming epoch of the Damingshan ore deposit is late Yanshanian.The large-scale mineralization in the Damingshan metallogenic belt of Guangxi might be attributed to the Mesozoic lithospheric extension in southern China.

关 键 词：白云母 40AR/39AR年龄 大明山钨矿 广西 

分 类 号：P618.67[天文地球—矿床学] P597.3[天文地球—地质学]