Zircon Xenocrysts from the Shaka Ridge Record Ancient Continental Crust: New U-Pb Geochronological and Oxygen Isotopic Data
文献类型:期刊论文
作者 | Skublov, Sergey G.1,2; Rumyantseva, Natalia A.2,3; Li, Qiuli4; Vanshtein, Boris G.3; Rezvukhin, Dmitriy, I5; Li, Xianhua4 |
刊名 | JOURNAL OF EARTH SCIENCE
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出版日期 | 2022-02-01 |
卷号 | 33期号:1页码:5-16 |
关键词 | zircon U-Pb geochronology oxygen isotopes trace elements rare earth elements Shaka Ridge South Atlantic Southwest Indian Ridge |
ISSN号 | 1674-487X |
DOI | 10.1007/s12583-021-1422-2 |
英文摘要 | Over the past two decades, a significant number of discoveries of ancient zircon xenocrysts in ocean-floor magmatic rocks have been reported. These findings provide compelling evidence for the presence of ancient continental crust within young oceanic lithosphere. Almost all finds of ancient zircon xenocrysts within oceanic crust are from the Mid-Atlantic Ridge. For other localities, however, similar data are very limited. This report presents the first age determinations (U-Pb, SHRIMP-II) and isotope-geochemical data (oxygen, trace and rare earth elements) for zircon xenocrysts from gabbro-diorites of the Shaka Ridge, in the vicinity of the Shaka fracture zone, near the western end of the Southwest Indian Ridge. The work is based on a study of bottom rock material dredged during expeditionary research on the R/V "Akademik Fedorov" (Russia) in 2016. The U-Pb isotope system of the zircon xenocrysts recorded a crystallization age of similar to 2.8 Ga at an upper discordia intercept and an age of similar to 600 Ma interpreted as the timing of a superimposed thermal event at a lower discordia intercept. The zircon xenocrysts show geochemical signatures of magmatic origin, i.e., fractionated REE distribution spectra with an increase in chondrite-normalized values from light to heavy REE, positive Ce anomalies and negative Eu anomalies, and high Th/U ratios (0.59-7.77). In discrimination diagrams based on a series of inter-element relationships, zircon compositions fall into the fields of zircons from rocks of continental crust, mostly granitoids. The Li content of the zircons is high (1.8 ppm-50 ppm), adding further evidence to their derivation from rocks of continental crust. During their residence within young oceanic crust, the zircon xenocrysts experienced alterations under the influence of submarine high-temperature hydrothermal fluids, which selectively affected the distribution of trace elements in the zircons and reduced the delta O-18 values to 1.75 parts per thousand-3.15 parts per thousand. The presence of obviously older zircons in Shaka gabbro-diorites clearly demonstrates the presence of ancient continental fragments and their recycling into the mantle at the western end of the Southwest Indian Ridge. |
WOS关键词 | MID-ATLANTIC RIDGE ; TRACE-ELEMENT COMPOSITION ; TH-PB ; HYDROTHERMAL ZIRCON ; OCEANIC-CRUST ; INDIAN-OCEAN ; UPPER-MANTLE ; ICP-MS ; EVOLUTION ; HF |
资助项目 | National Key R&D Program of China[2016YFE0203000] ; National Natural Science Foundation of China[41673018] ; Precambrian Geology and Geochronology of Russian Academy of Sciences[FMNU-2022-0005] ; state assignment project of IGM SB RAS |
WOS研究方向 | Geology |
语种 | 英语 |
WOS记录号 | WOS:000783670200002 |
出版者 | CHINA UNIV GEOSCIENCES, WUHAN |
资助机构 | National Key R&D Program of China ; National Key R&D Program of China ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; Precambrian Geology and Geochronology of Russian Academy of Sciences ; Precambrian Geology and Geochronology of Russian Academy of Sciences ; state assignment project of IGM SB RAS ; state assignment project of IGM SB RAS ; National Key R&D Program of China ; National Key R&D Program of China ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; Precambrian Geology and Geochronology of Russian Academy of Sciences ; Precambrian Geology and Geochronology of Russian Academy of Sciences ; state assignment project of IGM SB RAS ; state assignment project of IGM SB RAS ; National Key R&D Program of China ; National Key R&D Program of China ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; Precambrian Geology and Geochronology of Russian Academy of Sciences ; Precambrian Geology and Geochronology of Russian Academy of Sciences ; state assignment project of IGM SB RAS ; state assignment project of IGM SB RAS ; National Key R&D Program of China ; National Key R&D Program of China ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; Precambrian Geology and Geochronology of Russian Academy of Sciences ; Precambrian Geology and Geochronology of Russian Academy of Sciences ; state assignment project of IGM SB RAS ; state assignment project of IGM SB RAS |
源URL | [http://ir.iggcas.ac.cn/handle/132A11/105188] ![]() |
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 | Skublov, Sergey G. |
作者单位 | 1.Russian Acad Sci, Inst Precambrian Geol & Geochronol, St Petersburg 199034, Russia 2.St Petersburg Min Univ, St Petersburg 199106, Russia 3.Inst Geol & Mineral Resources World Ocean VNIIOke, St Petersburg 190121, Russia 4.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China 5.Russian Acad Sci, Sobolev Inst Geol & Mineral, Siberian Branch, Novosibirsk 630090, Russia |
推荐引用方式 GB/T 7714 | Skublov, Sergey G.,Rumyantseva, Natalia A.,Li, Qiuli,et al. Zircon Xenocrysts from the Shaka Ridge Record Ancient Continental Crust: New U-Pb Geochronological and Oxygen Isotopic Data[J]. JOURNAL OF EARTH SCIENCE,2022,33(1):5-16. |
APA | Skublov, Sergey G.,Rumyantseva, Natalia A.,Li, Qiuli,Vanshtein, Boris G.,Rezvukhin, Dmitriy, I,&Li, Xianhua.(2022).Zircon Xenocrysts from the Shaka Ridge Record Ancient Continental Crust: New U-Pb Geochronological and Oxygen Isotopic Data.JOURNAL OF EARTH SCIENCE,33(1),5-16. |
MLA | Skublov, Sergey G.,et al."Zircon Xenocrysts from the Shaka Ridge Record Ancient Continental Crust: New U-Pb Geochronological and Oxygen Isotopic Data".JOURNAL OF EARTH SCIENCE 33.1(2022):5-16. |
入库方式: OAI收割
来源:地质与地球物理研究所
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