Geochemistry of subducted metabasites exhumed from the Mariana forearc: Implications for Pacific seamount subduction
文献类型：期刊论文
| 作者 | Deng, Jianghong2,4,5; Zhang, Lipeng4,5; Liu, He4,5; Liu, Haiyang4,5; Liao, Renqiang1,4,5 ; Mastoi, Abdul Shakoor2,3; Yang, Xiaoyong2; Sun, Weidong1,4,5
|
| 刊名 | GEOSCIENCE FRONTIERS
 |
| 出版日期 | 2021-05-01 |
| 卷号 | 12期号:3页码:12 |
| 关键词 | IODP 366 Mariana convergent margin Forearc Seamount subduction OIB |
| ISSN号 | 1674-9871 |
| DOI | 10.1016/j.gsf.2020.12.002 |
| 通讯作者 | Liu, He(liuhe@qdio.ac.cn) |
| 英文摘要 | Seamounts on the drifting oceanic crust are inevitably carried by plate motions and eventually accreted or subducted. However, the geochemical signatures of the subducted seamounts and the significance of seamount subduction are not well constrained. Hundreds of seamounts have subducted beneath the Philippine Sea Plate following the westward subduction of the Pacific Plate since the Eocene (similar to 52 Ma). The subducted oceanic crust and seamount materials can be exhumed from the mantle depth to the seafloor in the Mariana forearc region by serpentinite mud volcanoes, providing exceptional opportunities to directly study the subducted oceanic crust and seamounts. The International Ocean Discovery Program (IODP) expedition 366 has recovered a few metamorphosed mafic clasts exhumed from the Mariana forearc serpentinite mud volcanoes, e.g., the Fantangisna and Asut Tesoru seamounts. These mafic clasts have tholeiitic to alkaline affinities with distinct trace elements and Nd-Hf isotopes characteristics, suggesting different provenances and mantle sources. The tholeiites from the Fantangisna Seamount have trace element characteristics typical of mid-ocean ridge basalt. The Pacific-type Hf-Nd isotopic compositions, combined with the greenschist metamorphism of these tholeiites further suggest that they came from the subducted Pacific oceanic crust. The alkali basalts-dolerites from the Fantangisna and Asut Tesoru seamounts show ocean island basalt (OIB)-like geochemical characteristics. The OIB-like geochemical signatures and the low-grade metamorphism of these alkali basalts-dolerites suggest they came from subducted seamounts that originally formed in an intraplate setting on the Pacific Plate. The Pacific Plate origin of these metabasites suggests they were formed in the Early Cretaceous or earlier. Two types of OIBs have been recognized from alkali metabasites, one of which is geochemically similar to the HIMU-EMI-type OIBs from the West Pacific Seamount Province, and another is similar to the EMII-type OIBs from the Samoa Island in southern Pacific, with negative Nb-Ta-Ti anomalies and enriched Nd-Hf isotopes. Generally, these alkali metabasites are sourced from the heterogeneous mantle sources that are similar to the present South Pacific Isotopic and Thermal Anomaly. This study provides direct evidence for seamount subduction in the Mariana convergent margins. We suggest seamount subduction is significant to element cycling, mantle heterogeneity, and mantle oxidation in subduction zones. (c) 2021 China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. |
| 资助项目 | Strategic Priority Research Program of the Chinese Academy of Sciences[XDA22050103] ; Strategic Priority Research Program of the Chinese Academy of Sciences[XDB420 20303] ; Strategic Priority Research Program of the Chinese Academy of Sciences[XDB18020102] ; National Natural Science Foundation of China[41803002] ; China Postdoctoral Science Foundation[2018 M642708] ; Qingdao National Laboratory for Marine Science and Technology[2017ASKJ02] ; Taishan Scholar Foundation of Shandong Province[ts201712075] |
| WOS研究方向 | Geology |
| 语种 | 英语 |
| WOS记录号 | WOS:000636463500031 |
| 出版者 | CHINA UNIV GEOSCIENCES, BEIJING |
| 源URL | [http://ir.qdio.ac.cn/handle/337002/170537]  |
| 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 | Liu, He |
| 作者单位 | 1.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 2.Univ Sci & Technol China, CAS Key Lab Crust Mantle Mat & Environm, Hefei 230026, Peoples R China 3.Univ Sindh, Ctr Pure & Appl Geol, Jamshoro 76080, Pakistan 4.Qingdao Natl Lab Marine Sci & Technol, Lab Marine Mineral Resources, Qingdao 266237, Peoples R China 5.Chinese Acad Sci, Ctr Deep Sea Res, Ctr Ocean Megasci, Inst Oceanol, Qingdao 266071, Peoples R China |
| 推荐引用方式 GB/T 7714 | Deng, Jianghong,Zhang, Lipeng,Liu, He,et al. Geochemistry of subducted metabasites exhumed from the Mariana forearc: Implications for Pacific seamount subduction[J]. GEOSCIENCE FRONTIERS,2021,12(3):12. |
| APA | Deng, Jianghong.,Zhang, Lipeng.,Liu, He.,Liu, Haiyang.,Liao, Renqiang.,...&Sun, Weidong.(2021).Geochemistry of subducted metabasites exhumed from the Mariana forearc: Implications for Pacific seamount subduction.GEOSCIENCE FRONTIERS,12(3),12. |
| MLA | Deng, Jianghong,et al."Geochemistry of subducted metabasites exhumed from the Mariana forearc: Implications for Pacific seamount subduction".GEOSCIENCE FRONTIERS 12.3(2021):12. |
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。