中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Silicon isotopic fractionation during metamorphic fluid activities: constraints from eclogites and ultrahigh-pressure veins in the Dabie orogen, China

文献类型:期刊论文

作者Li, Yuanhong3; Yu, Huimin3,4; Gu, Xiaofeng3; Guo, Shun1,2; Huang, Fang3,4
刊名CHEMICAL GEOLOGY
出版日期2020-05-05
卷号540页码:10
关键词Si isotopes Metamorphic vein Subduction-zone fluid Dabie orogen
ISSN号0009-2541
DOI10.1016/j.chemgeo.2020.119550
英文摘要To understand Si isotope fractionation during metamorphic fluid activities in the subduction zone, this study presents the Si isotopic compositions of two high- to ultrahigh-pressure (HP-UHP) eclogite-vein systems from the Ganghe and Hualiangting areas in the Dabie orogen, eastern China. The results show that Si isotopes are significantly fractionated between the veins and their host eclogites in both areas. The delta Si-30 values of Ganghe eclogites range from -0.50 parts per thousand to -0.39 parts per thousand, higher than that of the studied omphacite-epidote vein (-0.63 +/- 0.07 parts per thousand). The Hualiangting eclogites have delta Si-30 values of -0.36 parts per thousand to -0.29 parts per thousand, whereas the delta Si-30 values of the Hualiangting multi-stage veins show greater variation, from -0.45 parts per thousand to +0.05 parts per thousand, revealing significant Si isotope fractionation during metamorphic fluid evolution and vein formation. For the Hualiangting and Ganghe samples, the enrichment of heavy Si isotopes in minerals follows the order of delta Si-30(phengite) (-0.01 to +0.13 parts per thousand) approximate to delta Si-30(quartz) (-0.14 to +0.10 parts per thousand) > delta Si-30(omphacite) (-0.63 to -0.33 parts per thousand) approximate to delta Si-30(epidote) (-0.60 to -0.30 parts per thousand) approximate to delta Si-30(kyanite) (-0.42 to -0.28 parts per thousand) > delta Si-30(garnet) (-0.92 to -0.44 parts per thousand). The Si isotope fractionation between metamorphic minerals was generally consistent with the equilibrium Si isotope fractionation factors calculated by the first-principles methods. These results suggest that the vein minerals are likely in Si isotopic equilibrium with each other. The delta Si-30 of the Hualiangting veins are linearly correlated to SiO2 contents with a steeper slope than that of the magma differentiation trend. By also considering the mineralogy of the veins, we conclude that this linear relationship reflects the sequential variation of mineral composition on the Si isotope signature of the veins. The SiO2 content and delta Si-30 of veins increased with continuing crystallization from the fluid, and the delta Si-30 of the fluid also increased. The results suggest that Si isotope data can be used to constrain element recycling and metamorphic fluids activities in the subduction zones.
WOS关键词ROCK INTERACTION ; TRACE-ELEMENT ; COMPLETE MISCIBILITY ; EQUILIBRIUM SILICON ; BEARING ECLOGITES ; AQUEOUS FLUIDS ; HYDROUS FLUIDS ; DEGREES-C ; SUBDUCTION ; MOBILIZATION
资助项目Natural Science Foundation of China[41873009] ; Natural Science Foundation of China[41721002] ; Natural Science Foundation of China[41325011] ; Natural Science Foundation of China[41630206] ; Key Research Program of the Chinese Academy of Sciences[XDPB11] ; National Key Research and Development Program of China[2016YFC0600404]
WOS研究方向Geochemistry & Geophysics
语种英语
WOS记录号WOS:000525365400007
出版者ELSEVIER
资助机构Natural Science Foundation of China ; Natural Science Foundation of China ; Key Research Program of the Chinese Academy of Sciences ; Key Research Program of the Chinese Academy of Sciences ; National Key Research and Development Program of China ; National Key Research and Development Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; Key Research Program of the Chinese Academy of Sciences ; Key Research Program of the Chinese Academy of Sciences ; National Key Research and Development Program of China ; National Key Research and Development Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; Key Research Program of the Chinese Academy of Sciences ; Key Research Program of the Chinese Academy of Sciences ; National Key Research and Development Program of China ; National Key Research and Development Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; Key Research Program of the Chinese Academy of Sciences ; Key Research Program of the Chinese Academy of Sciences ; National Key Research and Development Program of China ; National Key Research and Development Program of China
源URL[http://ir.iggcas.ac.cn/handle/132A11/95545]  
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Huang, Fang
作者单位1.CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China
2.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, POB 9825, Beijing 100029, Peoples R China
3.Univ Sci & Technol China, Sch Earth & Space Sci, CAS Key Lab Crust Mantle Mat & Environm, Hefei 230026, Peoples R China
4.Univ Sci & Technol China, CAS Ctr Excellence Comparat Planetol, Hefei 230026, Peoples R China
推荐引用方式
GB/T 7714
Li, Yuanhong,Yu, Huimin,Gu, Xiaofeng,et al. Silicon isotopic fractionation during metamorphic fluid activities: constraints from eclogites and ultrahigh-pressure veins in the Dabie orogen, China[J]. CHEMICAL GEOLOGY,2020,540:10.
APA Li, Yuanhong,Yu, Huimin,Gu, Xiaofeng,Guo, Shun,&Huang, Fang.(2020).Silicon isotopic fractionation during metamorphic fluid activities: constraints from eclogites and ultrahigh-pressure veins in the Dabie orogen, China.CHEMICAL GEOLOGY,540,10.
MLA Li, Yuanhong,et al."Silicon isotopic fractionation during metamorphic fluid activities: constraints from eclogites and ultrahigh-pressure veins in the Dabie orogen, China".CHEMICAL GEOLOGY 540(2020):10.

入库方式: OAI收割

来源:地质与地球物理研究所

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