Knowledge Management System Of Institute of Oceanology, Chinese Academy of Sciences
| Oxygen fugacity and porphyry mineralization: A zircon perspective of Dexing porphyry Cu deposit, China | |
Zhang, Chan-chan1,4; Sun, Wei-dong2,3 ; Wang, Jin-tuan4,5; Zhang, Li-peng1,4; Sun, Sai-jun1; Wu, Kai1,4
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| 2017-06-01 | |
| 发表期刊 | GEOCHIMICA ET COSMOCHIMICA ACTA
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| 卷号 | 206页码:343-363 |
| 文章类型 | Article |
| 摘要 | Oxygen fugacity (fO(2)) is a key factor that controls the formation of porphyry Cu deposits. Porphyry Cu deposits are typically oxidized, but when and how porphyry magmas gain their high oxygen fugacity signatures, and how oxygen fugacity controls porphyry mineralization, remains obscure. To trace the origin of the high oxygen fugacity in porphyry Cu deposits, we determined trace element compositions and U-Pb ages of magmatic and inherited zircon from Dexing porphyry Cu deposit, calculated Ce4+/Ce3+ of zircons and estimated the oxygen fugacity of their parental magmas. The Ce4+/Ce3+ ratios of Middle Jurassic (similar to 170 Ma) magmatic zircons are high (550 on average), whereas the Ce4+/Ce3+ ratios of inherited zircons (200-880 Ma) are much lower (263 on average). The relationship suggests that the Dexing porphyry magma was highly oxidized when the Jurassic magmatic zircons crystallized (estimated fO(2): Delta FMQ + 0.7 (+/- 1.3) - Delta FMQ + 1.9 (+/- 1.3)), which cannot be attributed to partial melting of the Neoproterozoic arc crust (estimated fO(2): Delta FMQ - 2.4 (+/- 1.1) - Delta FMQ + 0.7 (+/- 1.2)) as proposed previously. Instead, the high fO(2) (Delta FMQ + 1.5) of these magmas is a primary feature of the latest magmatism. Sulfate rather than sulfide is the dominant species at fO(2) > Delta FMQ + 1.5. In general, the behavior of Cu and other chalcophile elements is controlled by sulfide, while the sulfur speciation is controlled by oxygen fugacity. Previous modeling results show that partial melting of mantle peridotite under high oxygen fugacity (even at >Delta FMQ + 1.5) cannot form Cu-rich magmas, which plausibly explains the lack of porphyry Cu deposits in normal arc rocks. This is because mantle peridotite has low Cu and S contents. Our modeling shows that partial melting of subducted oceanic crust, under oxygen fugacities higher than Delta FMQ + 1.5, is favorable for producing primary magmas with Cu contents sufficiently high for porphyry mineralization, which plausibly explains the close relationship between porphyry Cu deposits and oxidized magmas with adakitic affinities. (C) 2017 Elsevier Ltd. All rights reserved. |
| 关键词 | Porphyry Cu Deposit Zircon ce4+/ce3+ Ratio High Oxygen Fugacity Slab Melting Delta fmq+1.5 |
| DOI | 10.1016/j.gca.2017.03.013 |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000402488000020 |
| 引用统计 | |
| 文献类型 | 期刊论文 |
| 版本 | 出版稿 |
| 条目标识符 | http://ir.qdio.ac.cn/handle/337002/137079 |
| 专题 | 深海极端环境与生命过程研究中心 |
| 作者单位 | 1.Chinese Acad Sci, Guangzhou Inst Geochem, CAS Key Lab Mineral & Metallogeny, Guangzhou 510640, Guangdong, Peoples R China 2.Chinese Acad Sci, Inst Oceanol, Ctr Deep Sea Res, Qingdao 266071, Peoples R China 3.Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China 4.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 5.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Guangdong, Peoples R China |
| 推荐引用方式 GB/T 7714 | Zhang, Chan-chan,Sun, Wei-dong,Wang, Jin-tuan,et al. Oxygen fugacity and porphyry mineralization: A zircon perspective of Dexing porphyry Cu deposit, China[J]. GEOCHIMICA ET COSMOCHIMICA ACTA,2017,206:343-363. |
| APA | Zhang, Chan-chan,Sun, Wei-dong,Wang, Jin-tuan,Zhang, Li-peng,Sun, Sai-jun,&Wu, Kai.(2017).Oxygen fugacity and porphyry mineralization: A zircon perspective of Dexing porphyry Cu deposit, China.GEOCHIMICA ET COSMOCHIMICA ACTA,206,343-363. |
| MLA | Zhang, Chan-chan,et al."Oxygen fugacity and porphyry mineralization: A zircon perspective of Dexing porphyry Cu deposit, China".GEOCHIMICA ET COSMOCHIMICA ACTA 206(2017):343-363. |
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| 文件名称/大小 | 文献类型 | 版本类型 | 开放类型 | 使用许可 | ||
| Oxygen fugacity and （2248KB） | 期刊论文 | 出版稿 | 限制开放 | CC BY-NC-SA | 浏览 | |
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