Isotope systematics and metallogenetic age of Zhuanghe gold deposit, Liaoning province, China

Abstract

Based on the metallogenetic geology conditions, the H, O, C and S isotopic compositions were measured by MAT-251 mass spectrometer, and Pb isotope and Rb-Sr dating were carried with MAT-261 multi-acceptor mass spectrometer. The results show that the δ¹⁸O values of gold-bearing vein quartz from different levels are 1.19%–1.42%. The calculated δ¹⁸O values of ore fluids are 0.55%–0.78%, and δD values are from −8.64% to −6.66%. The calculated values of

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by the δ³⁴S_py values in quartz veins display sulfur isotope compositions from −0.053% to +0.413%. Carbon isotope compositions of carbonates are from −0.612% to 0.140%. The mole ratios of ²⁰⁶Pb to ²⁰⁴Pb, ²⁰⁷Pb to ²⁰⁴Pb and ²⁰⁸Pb to ²⁰⁴Pb in auriferous quartz vein are 16.987–17.545, 15.342–15.623, and 38.254–38.744, respectively. The age of the Zhuanghe gold deposit determined by Rb-Sr isochron of the fluid inclusions in quartzes is (143.0±5.8) Ma. These isotopic data suggest that the metallogenetic fluids are generated from magmatic hydrotherm and the origin of ore-forming matters is related to the deep-derived magmatic activities. Meanwhile, the metallogenetic epoch of the Zhuanghe gold deposit is in Yanshanian period.

Keywords

isotope systematics / metallogenetic age / Zhuanghe gold deposit

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