iScience (Oct 2020)

In situ U-Pb Dating of Calcite from the South China Antimony Metallogenic Belt

  • Kai Luo,
  • Jia-Xi Zhou,
  • Yue-Xing Feng,
  • I. Tonguc Uysal,
  • Ai Nguyen,
  • Jian-Xin Zhao,
  • Jiawei Zhang

Journal volume & issue
Vol. 23, no. 10
p. 101575

Abstract

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Summary: Accurately determining the age of hydrothermal ore deposits is difficult, because of lack of suitable mineral chronometers and techniques. Here we present the first LA-MC-ICPMS U-Pb age of carbonates from hydrothermal Sb deposits. Three stages of hydrothermal carbonates from the giant South China Sb metallogenic belt were identified: (1) pre-ore dolomite (Dol-I), (2) syn-ore calcite (Cal-II), and (3) post-ore calcite (Cal-III). The U and Pb isotopic data show that Cal-II yielded a lower intercept age of 115.3 ± 1.5 Ma (MSWD = 2.0), suggesting a Sb mineralization that corresponds to an extension event occurred during the early Cretaceous in South China. Although Cal-III yielded an age of 60.0 ± 0.9 Ma (MSWD = 1.5), indicating a potential tectonothermal event occurred in this belt during the early Cenozoic. Hence, in situ U-Pb dating of calcite offers a new way to determine the age of hydrothermal ore deposits.

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