首页 | 本学科首页   官方微博 | 高级检索  
     检索      

甘肃北山新元古代侵入岩的厘定及其对北山盆山演化格局的制约
作者姓名:王红杰  郭峰  冯乃琦  刘佳
作者单位:1.中国地质科学院郑州矿产综合利用研究所,河南 郑州 450006; 2.自然资源部多金属矿综合利用评价重点实验室,河南 郑州 450006; 3.西北地质科技创新中心,陕西 西安 710054
基金项目:中国地质调查局“东天山昌吉—双沟山地区区域地质调查(中国地质科学院郑州矿产综合利用研究所)(编号: DD20190067)”和“长江中游黄石—萍乡—德兴矿山集中区综合地质调查(编号: DD20190269)”项目联合资助
摘    要:北山地区是中亚造山带的组成部分,记录了重要的新元古代构造演化信息。对甘肃北山咸水沟原1:25万区域地质调查所划的泥盆纪侵入岩开展研究,新解体出新元古代二长花岗岩体,对该二长花岗岩进行LA-ICP-MS锆石U-Pb测年,其206Pb/238U加权年龄为(787 ±15)Ma。岩石富SiO2、低TiO2、高Al2O3、富碱,里特曼指数σ和铝饱和指数A/CNK均大于1.05,轻稀土相对于重稀土富集,(La/Yb)N值为15.20~23.28,表明轻重稀土高度分异,(La/Sm)N比值为3.14~4.22,指示轻稀土分馏较大,具明显的负Eu异常,富集Rb、Th、La,亏损Nb、P、Ti、Sr,表现出S型花岗岩特征。北山地区的新元古代二长花岗岩形成于大陆碰撞构造环境,位于Rodinia超大陆边缘,该期岩浆事件反映了新元古代北山地区发生了板块碰撞。

关 键 词:北山  新元古代  S型花岗岩  大陆碰撞  
收稿时间:2020-08-01

Confirmation of the granite during Neoproterozoic in Beishan of Gansu Province,and its constraints on the tectonic-evolutional pattern of Beishan orogen
Authors:WANG Hongjie  GUO Feng  FENG Naiqi  LIU Jia
Institution:1. Zhengzhou Institutes of Multipurpose Utilization of Mineral Resources, China Academy of Geological Sciences, Henan Zhengzhou 450006, China; 2. Key laboratory of Evaluation and Multipurpose Vtilization of Polymetallic Ore, Ministry of Natural Resources, Henan Zhengzhou 450006, China; 3. Northwest China Center for Geoscience Innovation, Shaanxi Xi'an 710054, China
Abstract:Beishan is located in Central Asia Belt, and records sighificant information of the Neoproterozoic tectonic evolution. The Neoproterozoic monzogranite was newly confirmed by studying the 1:250 000 Devonian intrusive pluton in Xianshuigou area, Beishan, Gansu Province. LA-ICP-MS zircon U-Pb dating of the monzonitic granite was carried out, the weighted age of 206Pb/238U is (787±15 )Ma. The monzogranite is characterized by high SiO2, low TiO2 , high Al2O3 , rich alkali, and σ and A/CNK is higher than 1.05. LREE is high relative to HREE. (La/Yb)N value is 15.20-23.28, which indicates LREE and HREE are highly differentiated, (La/Sm)N value is 3.14-4.22, which indicates LREE fractionation is large, δEu is negative. Rb, Th, La are high, Nb,P,Ti,Sr are depleted, showing the characteristics of S-type granite. The Neoproterozoic monzonitic granite was formed in the continental collision tectonic environment and located on the edge of Rodinia supercontinent. This magmatic event reflects the continental collision during Neoproterozoic in Beishan.
Keywords:Beishan  Neoproterozoic  S-type granite  continental collision  
点击此处可从《》浏览原始摘要信息
点击此处可从《》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号