Optimal magmatic oxidation conditions for giant porphyry copper deposits

作     者：Dian-Zhong Wang Jing-Jing Zhu Ruizhong Hu Massimo Chiaradia Xianwu Bi Ming-Liang Huang 汪殿钟;朱经经;胡瑞忠;Massimo Chiaradia;毕献武;黄明亮

作者机构：State Key Laboratory of Ore Deposit GeochemistryInstitute of GeochemistryChinese Academy of SciencesGuiyang 550081China College of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesBeijing 100049China Department of Earth SciencesUniversity of GenevaGeneva1205Switzerland 

出 版 物：《Science Bulletin》 (科学通报(英文版))

年 卷 期：2025年第70卷第6期

页      面：960-969页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：supported by the National Key Research and Development Program of China(2022YFC2903303) the Strategic Priority Research Program of Chinese Academy of Sciences(XDA0430301) the National Natural Science Foundation of China(42222206,42202104,42073047,and 42121003) the Hundred Talent Plan of the Chinese Academy of Sciences 

主　　题：Porphyry copper deposits Magmatic oxygen fugacity Precipitation efficiency 

摘      要：It is widely accepted that moderately to highly oxidized magmas are needed to form porphyry copper deposits(PCDs).However,only a few studies have attempted to investigate the effects of variable magmatic fO2 values on the formation of *** on previously published studies,the magma oxygen fugacity of giant PCDs is mainly concentrated betweenΔFMQ−0.5 andΔFMQ+2.5,with the first quartile,median,and third quartile being+0.8,+1.3,and+1.7,*** this work,we have carried out numerical modeling,which shows that the S^(2−)used to precipitate Cu accounts for approximately 90%of total sulfur atΔFMQ+1 but drops to 33%–38%and 15%–25%atΔFMQ+2 andΔFMQ+3,*** leads to a decrease of 88%–96%in Cu precipitation efficiencies fromΔFMQ+1 toΔFMQ+*** petrological model further shows that the maximum Cu precipitation efficiency(and,therefore,Cu endowments)occurs at aroundΔFMQ+***,therefore,highlight that moderately oxidized magma(ΔFMQ=∼1)rather than highly oxidized ones(ΔFMQ∼2)is optimal for the generation of giant PCDs.