Unveil the Redox Evolution of Ore-forming Fluids using Sulfur Isotope:A Case Study of the Zhengguang Intermediate Sulfidation Epithermal Au-Zn Deposit,NE China  

作　　者：WANG Le GAO Shen QIN Kezhang SONG Guoxue HAN Ri SU Shiqiang GUO Jihai PANG Xuyong LI Guangming 

机构地区：[1]Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China [2]Department of Earth Sciences,University of Geneva,Geneva 1205,Switzerland [3]School of Earth Science and Resources,China University of Geosciences,Beijing 100083,China [4]College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 101408,China [5]Heilongjiang Baoshan Mining Co.,Ltd.,Heihe,Heilongjiang 164300,China [6]Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China

出　　处：《Acta Geologica Sinica(English Edition)》2023年第5期1462-1474,共13页地质学报（英文版）

基　　金：jointly funded by the National Natural Science Foundation of China(Grant Nos.42202085,42272080);China Postdoctoral Science Foundation(Grant Nos.2020M680666,2021T140660);postdoctoral program of China Scholarship Council(Grant No.202104910161);National Key Research and Development Program of China(Grant No.2017YFC0601305)。

摘　　要：Oxygen fugacity(fO_(2))is a key intensity variable during the entire magmatic-hydrothermal mineralization courses.The redox state and its variations between different stages of the ore-forming fluids of intermediate sulfidation epithermal deposits are rarely deciphered due to the lack of appropriate approaches to determine fO_(2)of the fluids.Here,we reported theδ^(34)S of the sulfides from three different stages(stageⅠ,Ⅱ,Ⅲ)of Zhengguang,an Early Ordovician Au-rich intermediate sulfidation(IS)epithermal deposit,to decipher the redox evolution of the ore-forming fluids.The increasingδ^(34)S values from stageⅠpyrite(pyl,average-2.6‰)through py2(average-1.9‰)to py3(average-0.2‰)indicates a decrease of the oxygen fugacity of the ore-forming fluids.A compilation ofδ^(34)S values of sulfides from two subtypes of IS deposits(Au-rich and Ag-rich)from NE China shows that theδ^(34)S values of sulfides from Au-rich IS deposits are systematically lighter than those of Ag-rich IS Ag-Pb-Zn deposit,indicating the ore-forming fluids of the former are more oxidized than the latter.We highlight that sulfur isotopic composition of hypogene sulfides is an efficacious proxy to fingerprint the oxygen fugacity fluctuations of epithermal deposits and could potentially be used to distinguish the subtypes of IS deposits.

关 键 词：intermediate sulfidation EPITHERMAL sulfur isotope ore-forming fluids oxygen fugacity Zhengguang 

分 类 号：P618.43[天文地球—矿床学] P597[天文地球—地质学] P618.51