Trace Elements in Olivine Reveal Lithological and Redox Heterogeneity in the Mantle Source of Carbonated Silicate Melts: Constraints from Cenozoic Melilitites in the West Qinling Orogen, China
文献类型：期刊论文
| 作者 | Zhang, Fang-Yi1,3; Lai, Shao-Cong3; Zhu, Ren-Zhi3; Zhang, Li-Peng1; Zhu, Yu2; Yang, Hang3; Yang, Zhen3; Qin, Jiang-Feng3; Zhao, Shao-Wei4; Zhong, Zhe-Hao3 |
| 刊名 | JOURNAL OF PETROLOGY
 |
| 出版日期 | 2025-09-01 |
| 卷号 | 66期号:9页码:20 |
| 关键词 | olivine oxygen fugacity mantle heterogeneity deep carbon cycle melilitites |
| ISSN号 | 0022-3530 |
| DOI | 10.1093/petrology/egaf081 |
| 通讯作者 | Zhang, Fang-Yi(zhangfy@qdio.ac.cn) ; Lai, Shao-Cong(shaocong@nwu.edu.cn) |
| 英文摘要 | The speciation of carbon in the mantle is predominantly governed by oxygen fugacity (fO2). Under oxidized conditions, carbon is present as carbonate minerals or CO2, which significantly lowers the solidus of mantle lithologies, inducing partial melting and generating carbonatitic to carbonated silicate melts. In contrast, reduced forms such as diamond or graphite remain immobile. Therefore, the formation of carbonated silicate melts and the deep carbon cycling are critically influenced by both the redox state of the mantle and the presence of carbon-rich lithologies. However, systematic studies investigating the lithology and redox state of mantle source remain scarce. Here, we present high-precision major and trace element compositions of olivine phenocrysts from Cenozoic melilitites in the West Qinling orogen, China, to investigate the lithology and redox conditions of the mantle source for carbonated silicate melts. Distinct olivine compositions and redox states are observed among different regions. Olivines from Baiguan and Jiangkou display low Ni, high Ca, elevated Mn/Fe and Mn/Zn ratios, and high fO2 (Delta FMQ +0.55 +/- 0.43, 1 sigma). In contrast, olivines from Baihe exhibit high Ni, low Ca, low Mn/Fe and Mn/Zn ratios, and lower fO2 (Delta FMQ -0.14 +/- 0.24, 1 sigma). Quantitative modeling indicates that the compositional diversity cannot be attributed to fractional crystallization, diffusion, or variations in fO2 during melt evolution. Instead, they point to distinct mantle lithologies: an oxidized, carbonated peridotite source for the Baiguan and Jiangkou melilitites and a reduced pyroxenite source for the Baihe melilitites. Thermobarometric calculations suggest that the West Qinling melilitites formed at pressures of 4.4 +/- 0.2 GPa (1 sigma) and mantle potential temperatures of 1376 +/- 27 degrees C (1 sigma). When corrected to the source conditions, the fO2 of carbonated peridotite mantle source is Delta FMQ -0.21 +/- 0.52 (1 sigma), corresponding to mantle Fe3+/Sigma Fe ratios of 7%-10%, significantly higher than that of ambient mantle and lithospheric mantle. These findings suggest that a highly oxidized, carbon-rich mantle source, rather than elevated mantle temperatures, is essential for the generation of carbonated silicate melts. Coupled with stable Mg-Ca-Zn isotope data, we propose that subducted carbonate sediments react with reduced ambient mantle at transition zone depth, either through carbonate melts or in the solid state, producing Fe3+- and carbon-rich peridotites. During subsequent adiabatic ascent, these peridotites undergo redox melting, generating oxidized carbonated silicate melts. |
| WOS关键词 | 1ST-ROW TRANSITION-ELEMENTS ; CONTINENTAL FLOOD BASALTS ; OXIDATION-STATE ; OXYGEN FUGACITY ; ELECTRICAL-CONDUCTIVITY ; LITHOSPHERIC MANTLE ; ALKALIC MAGMAS ; MORB GLASSES ; FERRIC IRON ; DEEP CARBON |
| 资助项目 | National Natural Science Foundation of China[42172056] ; National Natural Science Foundation of China[42303054] ; Shandong Provincial Natural Science Foundation[ZR2023QD059] ; Opening Foundation of State Key Laboratory of Continental Dynamics, Northwest University[22LCD14] |
| WOS研究方向 | Geochemistry & Geophysics |
| 语种 | 英语 |
| WOS记录号 | WOS:001574522700001 |
| 出版者 | OXFORD UNIV PRESS |
| 源URL | [http://ir.qdio.ac.cn/handle/337002/203392]  |
| 专题 | 海洋研究所_深海极端环境与生命过程研究中心 |
| 通讯作者 | Zhang, Fang-Yi; Lai, Shao-Cong |
| 作者单位 | 1.Chinese Acad Sci, Inst Oceanol, Ctr Deep Sea Res, 7 Nanhai Rd, Qingdao 266071, Peoples R China 2.Yangtze Univ, Coll Resources & Environm, YU CUGW Joint Res Ctr Deep Earth & Surface Dynam C, Hubei Key Lab Petr Geochem & Environm, 111 Univ Rd, Wuhan 430100, Peoples R China 3.Northwest Univ, Dept Geol, State Key Lab Continental Evolut & Early Life, 229 North Taibai Rd, Xian 710069, Peoples R China 4.Changan Univ, Sch Earth Sci & Resources, Key Lab Western Chinas Mineral Resources & Geol En, Minist Educ, 126 Yanta Rd, Xian 710054, Peoples R China |
| 推荐引用方式 GB/T 7714 | Zhang, Fang-Yi,Lai, Shao-Cong,Zhu, Ren-Zhi,et al. Trace Elements in Olivine Reveal Lithological and Redox Heterogeneity in the Mantle Source of Carbonated Silicate Melts: Constraints from Cenozoic Melilitites in the West Qinling Orogen, China[J]. JOURNAL OF PETROLOGY,2025,66(9):20. |
| APA | Zhang, Fang-Yi.,Lai, Shao-Cong.,Zhu, Ren-Zhi.,Zhang, Li-Peng.,Zhu, Yu.,...&Xia, Yu-Hong.(2025).Trace Elements in Olivine Reveal Lithological and Redox Heterogeneity in the Mantle Source of Carbonated Silicate Melts: Constraints from Cenozoic Melilitites in the West Qinling Orogen, China.JOURNAL OF PETROLOGY,66(9),20. |
| MLA | Zhang, Fang-Yi,et al."Trace Elements in Olivine Reveal Lithological and Redox Heterogeneity in the Mantle Source of Carbonated Silicate Melts: Constraints from Cenozoic Melilitites in the West Qinling Orogen, China".JOURNAL OF PETROLOGY 66.9(2025):20. |
入库方式： OAI收割
来源：海洋研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。