Conditions and processes leading to large-scale gold deposition in the Jiaodong province,eastern China  

作　　者：Hongrui FAN Tingguang LAN Xinghui LI M.SANTOSH Kuifeng YANG Fangfang HU Kai FENG Huanlong HU Hongwei PENG Yongwen ZHANG 

机构地区：[1]Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,100029,China [2]College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing,100049,China [3]Innovation Academy for Earth Science,Chinese Academy of Sciences,Beijing,100029,China [4]State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang,550081,China [5]State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences Beijing,Beijing,100083,China [6]State Key Laboratory of Mineral Processing,BGRIMM Technology Group,Beijing,102628,China [7]School of Geosciences and Info-physics,Central South University,Changsha,410012,China

出　　处：《Science China Earth Sciences》2021年第9期1504-1523,共20页中国科学（地球科学英文版）

基　　金：supported by the National Key Research and Development Program(Grant No.2016YFC0600105);the National Natural Science Foundation of China(Grant Nos.41672094,41772080)。

摘　　要：The gold deposits in the Jiaodong Peninsula constitute the largest gold mineralized province in China.The mineralization shows common characteristics in their tectonic setting,ore-forming fluid and metallogenic system.Sulfidation and fluid immiscibility are two important mechanisms controlling gold precipitation,both of which consume sulfur in the oreforming fluids.The escape of H2S from the main ore-forming fluids and the decrease of total sulfur concentration not only lead to the efficient precipitation of gold,but also result in the crystallization of reducing minerals such as pyrrhotite and oxidizing minerals such as magnetite.Quartz solubility shows strong dependence on temperature,pressure,and CO2 content.The dependence of quartz solubility on pressure is weak at low temperatures,and progressively stronger at higher temperatures.Similarly,the temperature dependence of quartz solubility is relatively low at low pressures,but becomes gradually stronger at high pressures.The results of solubility modeling can constrain the dissolution and reprecipitation behavior of quartz in the oreforming veins and the formation mechanism of different types of quartz veins.The multi-stage mineralization fluid activity resulted in the complex dissolution structure of quartz in the Jiaodong gold veins.Pyrite in the main metallogenic period in the Jiaodong gold deposits shows complex microstructure characteristics at single crystal scale.The trace elements(mainly the coupling of As-and Au-rich belt)and sulfur isotope composition also display a certain regularity.The As-rich fluids might have formed by the initial pulse of ore-forming fluids through As-rich metasedimentary strata,while the As-Au oscillation zone at the margin of pyrite grains is related to the pressure fluctuation caused by fault activity and the local phase separation of fluids.There is a temporal and spatial evolution of gold fineness in the Jiaodong gold deposits.Water/rock reaction(sulfidation)was the main ore-forming mechanism of early gold mineralization,f

关 键 词：Mineral precipitation Mineral assemblage Gold fineness Ore-forming condition and processes Gold deposit Jiaodong 

分 类 号：P618.51[天文地球—矿床学]