摘要
位于南岭东段北部赣南地区兴国县境内的杨村岩体,侵入于前寒武纪基底变质岩中,其西侧又与白垩系赣州组砂岩、砾岩断层接触,因而其地质年代难以根据接触关系准确判断,而岩体本身风化程度比较高,难以利用K-Ar法和Rb-Sr等时线等方法获得可靠年龄,以往将该岩体归属于加里东期。文章采用激光剥蚀-多接收器电感耦合等离子体质谱(LA-MC-ICPMS)锆石U-Pb定年方法,获得其锆石206Pb/238U加权平均年龄为(175.8±1.0)Ma,从而准确地查明该岩体侵位于燕山早期第一阶段与第二阶段的过渡时期。这一阶段在南岭是钨多金属发生大规模成矿作用的开始阶段,因而杨村岩体地质年代的确定为今后的地质找矿提供了新的线索。
The Yangcun granite mass is located northeast of Nanling and Xingguo country of the South Jiangxi area. It intrudes into metamorphosed rocks of Precambrian basement, and is adjacent to Cretaceous Sandstone and conglomerate at its west side with a fault. The forming time of this granite masses is difficult to judge correctly by its contact relations, and it was previously assigned to the Caledonian period. In this paper, we give a U-Pb age of （175.8 ＋ 1. 0 ） Ma of zircon by Laser Ablation-Muhicollector Inductively Coupled Plasma-Mass Spectrometry （LA-MC-ICPMS） dating technology, thus ascertaining this granite mass as an intrusion during the period between the first and second stage of the early Yanshanian, and this period is the onset period of extensive mineralization of tungsten and multi-metals in the Nanling area. Therefore, the determination of the geochronology of the Yangcun granite masses will provide new information for prospecting in the future.
出处
《岩矿测试》
CAS
CSCD
北大核心
2012年第3期549-553,共5页
Rock and Mineral Analysis
基金
中国地质大调查项目"南岭地区岩浆岩成矿专属性研究"(1212011120989)
"我国重要矿产和区域成矿规律研究"课题(1212010633903)
国家深部探测技术与实验研究专项"南岭成矿带地壳岩浆系统结构探测实验"(SinoProbe 0301)
"南岭于都-赣县矿集区立体探测技术与深部成矿预测示范"课题(201011048)
危机矿山"赣南地区钨矿床成矿规律总结及高温热液成矿机制研究"课题(20089947)
