Geological settings and metallogenesis of high-grade iron deposits in China  

作　　者：Zhaochong ZHANG Houmin LI Jianwei LI Xie-Yan SONG Hao HU Lixing LI Fengmei CHAI Tong HOU Deru XU 

机构地区：[1]State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China [2]Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China [3]State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China [4]State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550002,China [5]Xinjiang Key Laboratory for Geodynamic Processes and Metallogenic Prognosis of the Central Asian Orogenic Belt,Xinjiang University,Urumqi 830046,China [6]State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,China [7]CAS Key Laboratory of Mineralogy and Metallogeny,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China

出　　处：《Science China Earth Sciences》2021年第5期691-715,共25页中国科学（地球科学英文版）

基　　金：supported by the National Basic Research Program of China(Grant No.2012CB416800)。

摘　　要：The predominant types of high-grade iron deposits in China include skarn,sedimentary metamorphic(banded ironformation,BIF-type),continental/submarine volcanic-hosted and magmatic Fe-Ti-Voxide deposits.Based on a comprehensive review of current studies on these deposits,this paper suggests that the oxygen concentration in atmosphere played an important role for the formation of BIFs,whereas the tectonic setting and deep magmatic differentiation processes are more important for the other types.Notably,both high temperature and high pressure experiments and melt inclusion studies indicate that during the differentiation,high temperature magmas could develop iron-rich magma via liquid immiscibility but not pure oxide melt("iron ore magma").Fe-P melt could be generated directly by liquid immiscibility under hydrous and oxidized condition.The formation of high-grade iron deposits is mostly associated with the processes related to multiple stages of superimposition,e.g.,desiliconization and iron enrichment,removal of impurity,and remobilization and re-precipitation of iron.According to the temporal evolution,the high-grade iron deposit could be divided into multi-episode superimposition type(temporally discontinuous mineralization)and multi-stage superimposition type(temporally continuous mineralization).The former is represented by the sedimentary metamorphic iron deposit,and the latter includes those related to magmatic-hydrothermal fluids(e.g.,skarn,volcanic-hosted and magmatic types).

关 键 词：High-grade iron deposit METALLOGENESIS Iron ore magma Liquid immiscibility Fe-rich fluid 

分 类 号：P618.31[天文地球—矿床学]