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Chinese Science Bulletin

, Volume 45, Issue 8, pp 764–767 | Cite as

Zircon U/Pb ages for gniess from Qianshan, Anhui

  • Daogong Chen
  • Clark Isachsen
  • Xiachen Zhi
  • Taxi Zhou
  • Hou Cheng
  • Qunke Xia
Notes

Abstract

Zircon U/Pb ages were measured for Qianshan gneiss at the ultrahigh pressure metamorphic (UHPM) complex in the Southern Dabie Terrain (SDT). According to morphology, Th and U contents of eight fractions of zircon and data distribution on the discordia, it is indicated that they should be treated as metamorphic overgrowth mixing zircons, in which the cores mainly are magmatic and the outers were metamorphic. The intercept ages show that the gneiss underwent UHPM. There is no direct correlation for zircon between morphological feature and genesis.

Keywords

overgrowth mixing zircon UHPM Dabieshan 

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Copyright information

© Science in China Press 2000

Authors and Affiliations

  • Daogong Chen
    • 1
  • Clark Isachsen
    • 2
  • Xiachen Zhi
    • 1
  • Taxi Zhou
    • 1
  • Hou Cheng
    • 1
  • Qunke Xia
    • 1
  1. 1.Department of Earth and Space SciencesUniversity of Science and Technology of ChinaHefeiChina
  2. 2.Department of GeosciencesUniversity of ArizonaUSA

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