坦桑尼亚古元古代姆柏兹地体锆石U- Pb- Hf同位素特征及其指示的构造环境研究
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

基金项目:

本文为中国地质调查局项目(编号 DD20160108,DD20190439,1212011220910)和商务部援外项目\[2015\]352)联合资助成果。


Zircon U- Pb- Hf isotopic characteristics and the indicative geotectonic environment of the Paleoproterozoic Mbozi terrain, Tanzania
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    通过研究坦桑尼亚乌本迪变质活动带内姆柏兹地体(初)糜棱岩的锆石U- Pb- Hf同位素特征,认为初糜棱岩物质来源于古老地壳的再循环。对比研究坦桑尼亚鲁呼呼盆地和鲁夸盆地卡鲁超群沉积特征,结合卡鲁超群底部砂岩的碎屑锆石年龄谱系特征,推测鲁夸盆地内卡鲁系的最大沉积时限为晚石炭纪- 早二叠纪,其物质来源于乌本迪带或南部伊鲁米德带内的新元古代- 寒武纪岩浆岩。通过计算碎屑锆石年龄与地层沉积时代差值的累频分布特征,确定了晚古生代时期的鲁夸沉积盆地构造属性为拉张背景的陆间裂谷。结合本次锆石U- Pb- Hf同位素特征研究和区域地质资料分析结果,认为姆柏兹地体经历了两次俯冲- 造山- 裂解(伸展)构造旋回,响应了哥伦比亚超大陆、罗迪尼亚超大陆的聚合、裂解。冈瓦纳大陆裂解期间形成的裂谷盆地接受沉积,形成了卡鲁超群沉积。

    Abstract:

    The study of zircon U- Pb- Hf isotopic characteristics of the mylonites from the Mbozi terrain in the Ubendian meta- mobile belt, Tanzania, leads to the conclusion that the primary mylonitesoriginated from ancient crust recycling. Combined with the feature of detrital zircon age spectrum and a comparativestudy ofthe Ruhuhu basin and Rukwa basin sedimentary characteristics, it is suggested that the maximum depositional age of the Karoo Supergroup in the Rukwa basin is late Carboniferous to early Permian, and the materials werederived from Neoproterozoic- Cambrian magmatic rocks in either the Ubendian belt or the Southern Irumide belt. By calculating the frequency distribution characteristics of the difference between detrital zircon ages and stratigraphic sedimentary ages, it is determined that the Paleoproterozoic Rukwa sedimentary basin sedimentary basin was structurally an intercontinental rift. Based on the zircon U- Pb- Hf isotopic characteristics and regional geological data, it is concluded that the Mbozi terrain underwent two subduction- orogeny- cracking (extension) tectonic cycles, which were in response to the convergence of the Colombia and Rodina supercontinents,and breakup of Colombia and Rodina supercontinents. Karoo Group wasformed in the intercontinental rift during the breakup of theGondwana supercontinent.

    参考文献
    相似文献
    引证文献
引用本文

何胜飞,刘晓阳,孙凯,吴兴源,卢宜冠,王杰,许康康,龚鹏辉.2021.坦桑尼亚古元古代姆柏兹地体锆石U- Pb- Hf同位素特征及其指示的构造环境研究[J].地质学报,95(4):976-998.
HE Shengfei, LIU Xiaoyang, SUN Kai, WU Xingyuan, LU Yiguan, WANG Jie, XU Kangkang, GONG Penghui.2021. Zircon U- Pb- Hf isotopic characteristics and the indicative geotectonic environment of the Paleoproterozoic Mbozi terrain, Tanzania[J]. Acta Geologica Sinica,95(4):976-998.

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2020-07-22
  • 最后修改日期:2020-09-12
  • 录用日期:2020-11-09
  • 在线发布日期: 2020-11-17
  • 出版日期: