地质科学
     首页 | 过刊浏览 |  本刊介绍 |  编委会 |  投稿指南 |  期刊征订 |  留言板 |  批评建议 |  联系我们 |  English
地质科学  2019, Vol. 54 Issue (1): 265-288    DOI: 10.12017/dzkx.2019.016
论文 最新目录 | 下期目录 | 过刊浏览 | 高级检索  |   
江西南部东坑盆地流纹岩地球化学特征及其地质意义
韦昌袭2    巫建华1,2    张婧妍2    刘    帅1
  1. 东华理工大学核资源与环境国家重点实验室培育基地  南昌    330013;
  2. 东华理工大学地球科学学院  南昌    330013
Geochemistry and tectonic implications of the rhyolite in Dongkeng Basin, southern Jiangxi Provinc
Wei Changxi2    Wu Jianhua1, 2    Zhang Jingyan2    Liu Shuai1
  1. State Key Laboratory Breeding Base of Nuclear Resources and Environment, East China University of Technology, Nanchang, Jiangxi  330013;
  2. Collage of Earth Science, East China University of Technology, Nanchang, Jiangxi  330013
 全文: PDF (9718 KB)   HTML( )   输出: BibTeX | EndNote (RIS)      背景资料
摘要 

东坑盆地位于南岭构造带东段,其中的流纹岩为该带燕山期最早的“流纹岩—玄武岩”双峰式火山岩组合的酸性端元。主量元素、微量元素、Sr-Nd-Pb-O-Hf同位素研究表明,流纹岩富硅、钾,贫镁、钙、钛,属亚碱性弱过铝质岩石;稀土元素富集,轻重稀土分异和铕负异常明显,表现典型的M型稀土元素4分组效应,富集高场强元素Ta、Hf、Zr、Nb、Ce、Y和大离子亲石元素Rb、Th、U、Ba、Ga,亏损大离子亲石元素Sr,具有A型流纹岩和高Sr-Ba流纹岩的微量元素特征;(87Sr/86Sr)i较高,(206Pb/204Pb)i、(207Pb/204Pb)i和(208Pb/204Pb)i较低,εNdt)、εHft)和δ18OV-SMOW较高,TDM2(Nd)和TDM2(Hf)较小。这些特征表明, 东坑盆地流纹岩是拉张构造环境下源于新元古代亏损地幔和少量古老下地壳物质混合而成年轻下地壳部分熔融的产物,为早侏罗世早期南岭构造带东段处于拉张构造环境、地壳属正常厚度提供了岩石学证据。

服务
把本文推荐给朋友
加入我的书架
加入引用管理器
E-mail Alert
RSS
作者相关文章
韦昌袭 巫建华 张婧妍 刘帅
关键词流纹岩   Sr-Nd-Pb-Hf-O同位素   年轻下地壳   早侏罗世早期   东坑盆地     
Abstract

The Dongkeng Basin is located in the eastern section of Nanling tectonic belt. The rhyolite as the acidic end-menber of bimodal volcanic rock association, is the most ancient rhyolite that distinguish from the southern China during the Yanshanian period. The rhyolites in the study area is characterized by high SiO2, K2O, and low MgO, CaO, TiO2, and plot in the field of sub alkaline and weakly peraluminous series in the SiO2 vs K2O and A/CNK vs A/NK diagrams. The primitive mantle(PM)-normalized trace element patterns of all of these rocks are enriched in large ion lithophile elements(LILE, such as Rb, Ba, Th, U)and depleted in high field strength elements(HFSE, such as Nb, Ta, Hf, Zr). The rhyolite are characterized by light REE(LREE)enrichments, with weakly differentiated heavy REE(HREE)and significant negative Eu anomalies, which shows typical M-type tetrad effects. Moreover, the Sr-Nd-Pb-O-Hf isotopic compositions show low ;(87Sr/86Sr)i,(206Pb/204Pb)i,(207Pb/204Pb)i and(208Pb/204Pb)i, high εNdt)、εHft)and δ18OV-SMOW‰ value, and low TDM2(Nd)and TDM2(Hf). The comprehensive analysis of rhyolite's geochemical characteristics indicates that Dongkeng Basin rhyolite originates from the Neoproterozoic of depleted mantle and enriched mantle type-II and mixed with a small amount of ancient light lower crust during the Early Jurassic and early products of partial melting of extensional tectonic environment, providing the petrology of evidence for the early stage of Early Jurassic in Nanling belt which crust is normal thickness.

Key wordsRhyolite   Sr-Nd-Pb-Hf-O isotopes   Young lower crust   Early Early Jurassic   Dongkeng Basin   
收稿日期: 2018-01-27; 出版日期: 2019-01-10
基金资助:

中国核工业集团总公司项目(编号:中核地计 [2008] 74号)资助。

通讯作者: 巫建华,男,1960年3月生,博士,教授,矿床学和地球化学专业。     E-mail: jhwu@ecit.cn
作者简介: 韦昌袭,男,1992年4月生,硕士研究生,地球化学专业。E-mail:841223877@qq.com
引用本文:   
韦昌袭 巫建华 张婧妍 刘帅. 2019, 江西南部东坑盆地流纹岩地球化学特征及其地质意义. 地质科学, 54(1): 265-288.
Wei Changxi Wu Jianhua Zhang Jingyan Liu Shuai. Geochemistry and tectonic implications of the rhyolite in Dongkeng Basin, southern Jiangxi Provinc[J]. Chinese Journal of Geology, 2019, 54(1): 265-288.
 
没有本文参考文献
[1] 孙毅 牛漫兰 李秀财 吴齐 蔡倩茹 苑潇宇 文凤玲 李晨. 拉脊山阿伊山群中流纹岩的形成时代、地球化学特征及其构造意义[J]. 地质科学, 2019, 54(3): 1016-1030.
[2] 葛文春, 李献华, 林强, 孙德有, 吴福元, 尹成孝. 呼伦湖早白垩世碱性流纹岩的地球化学特征及其意义[J]. 地质科学, 2001, (2): 176-183.
 
版权所有 © 2009-2017 《地质科学》编辑部
地址:北京9825信箱  邮政编码:100029
电话:010-82998109  010-82998115