Magnesium Isotope Composition of Subduction Zone Fluids as Constrained by Jadeitites From Myanmar
文献类型:期刊论文
作者 | Chen, Yi1,2,3; Huang, Fang4; Shi, Guang-Hai5; Wu, Fu-Yuan1,2; Chen, Xi4; Jin, Qi-Zhen4; Su, Bin1; Guo, Shun1,2; Sein, Kyaing6; Thet Tin Nyunt7 |
刊名 | JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
![]() |
出版日期 | 2018-09-01 |
卷号 | 123期号:9页码:7566-7585 |
关键词 | Magnesium isotopes subduction zone fluids subduction channel jadeitite carbonate dissolution |
ISSN号 | 2169-9313 |
DOI | 10.1029/2018JB015805 |
英文摘要 | Subduction zone fluids are critical for transporting materials from subducted slabs to the mantle wedge. Jadeitites from Myanmar record fluid compositions and reactions in the forearc subduction channel. Here we present high-precision Mg isotope data of the Myanmar jadeitites and associated rocks to understand the Mg isotope composition of subduction zone fluids at forearc depths. Two types of jadeitites (white and green) exhibit distinct Mg isotope compositions. The white jadeitites precipitated from Na-Al-Si-rich fluids and have low Mg-26 values, varying from -1.55 to -0.92, whereas the green jadeitites have higher Mg-26 values (-0.91 to -0.74) due to metasomatic reactions between fluids and Cr spinel. The amphibole-rich blackwall in the contact boundaries between jadeitites and serpentinites also exhibits low Mg-26 values (-1.17 parts per thousand to -0.72 parts per thousand). Therefore, the jadeite-forming fluids have not only high concentrations of Na-Al-Si but also low Mg-26 values. The low Mg-26 signature of the fluids is explained by the dissolution of Ca-rich carbonate in subducted sediments or altered oceanic crust, which is supported by the negative correlation of Mg-26 with CaO/TiO2, CaO/Al2O3, and Sr in the white jadeitites. Given the common occurrence of Ca-rich carbonates in the subduction channel, the Mg isotope composition of low-Mg aqueous fluids would be significantly modified by dissolved carbonates. Metasomatism by such fluids along conduits has the potential to generate centimeter-scale Mg isotope heterogeneity in the forearc mantle wedge. Therefore, Mg isotopes could be a powerful tracer for recycled carbonates not only in the deep mantle but also in the shallow regions of subduction zones. |
WOS关键词 | UPPER-MANTLE CONDITIONS ; TRACE-ELEMENT ; HIGH-PRESSURE ; MARINE-SEDIMENTS ; ROCK INTERACTION ; CHROMIAN SPINEL ; EASTERN CHINA ; CONTINENTAL SUBDUCTION ; METASOMATIC PROCESSES ; SERPENTINIZED MANTLE |
资助项目 | National Science Foundation of China[41490614] ; National Science Foundation of China[41822202] ; International Partnership Program[GJHZ1776] ; Chinese Academy of Sciences[XDB18000000] |
WOS研究方向 | Geochemistry & Geophysics |
语种 | 英语 |
WOS记录号 | WOS:000447858800022 |
出版者 | AMER GEOPHYSICAL UNION |
资助机构 | National Science Foundation of China ; National Science Foundation of China ; International Partnership Program ; International Partnership Program ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; International Partnership Program ; International Partnership Program ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; International Partnership Program ; International Partnership Program ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; International Partnership Program ; International Partnership Program ; Chinese Academy of Sciences ; Chinese Academy of Sciences |
源URL | [http://ir.iggcas.ac.cn/handle/132A11/89153] ![]() |
专题 | 地质与地球物理研究所_岩石圈演化国家重点实验室 |
通讯作者 | Chen, Yi; Huang, Fang |
作者单位 | 1.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing, Peoples R China 2.Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing, Peoples R China 3.Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Beijing, Peoples R China 4.Univ Sci & Technol China, Geochem Dept Human Resources, Hefei, Anhui, Peoples R China 5.China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Beijing, Peoples R China 6.Myanmar Geosci Soc, Hlaing Univ Campus, Yangon, Myanmar 7.Univ Yangon, Dept Geol, Yangon, Myanmar |
推荐引用方式 GB/T 7714 | Chen, Yi,Huang, Fang,Shi, Guang-Hai,et al. Magnesium Isotope Composition of Subduction Zone Fluids as Constrained by Jadeitites From Myanmar[J]. JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,2018,123(9):7566-7585. |
APA | Chen, Yi.,Huang, Fang.,Shi, Guang-Hai.,Wu, Fu-Yuan.,Chen, Xi.,...&Thet Tin Nyunt.(2018).Magnesium Isotope Composition of Subduction Zone Fluids as Constrained by Jadeitites From Myanmar.JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,123(9),7566-7585. |
MLA | Chen, Yi,et al."Magnesium Isotope Composition of Subduction Zone Fluids as Constrained by Jadeitites From Myanmar".JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH 123.9(2018):7566-7585. |
入库方式: OAI收割
来源:地质与地球物理研究所
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。