The influence of a subduction component on magmatism in the Okinawa Trough: Evidence from thorium and related trace element ratios | |
Guo, Kun1,2; Zeng, Zhi-Gang1,2; Chen, Shuai1,2; Zhang, Yu-Xiang1; Qi, Hai-Yan1,2; Ma, Yao1,2 | |
2017-09-01 | |
发表期刊 | JOURNAL OF ASIAN EARTH SCIENCES |
卷号 | 145页码:205-216 |
文章类型 | Article |
摘要 | The Okinawa Trough (OT) is a back-arc, initial continental marginal sea basin located behind the Ryukyu Arc Trench System. Formation and evolution of the OT have been intimately related to subduction of the Philippine Sea Plate (PSP) since the late Miocene; thus, the magma source of the trough has been affected by subduction components, as in the case of other active back-arc basins, including the Lau Basin (LB) and Mariana Trough (MD. We review all the available geochemical data relating to basaltic lavas from the OT and the middle Ryukyu Arc (RA) in this paper in order to determine the influence of the subduction components on the formation of arc and back-arc magmas within this subduction system. The results of this study reveal that the abundances of Th in OT basalts (OTBs) are higher than that in LB (LBBs) and MT basalts (MTBs) due to the mixing of subducted sediments and EMI-like enriched materials. The geochemical characteristics of Th and other trace element ratios indicate that the OTB originated from a more enriched mantle source (compared to N-mid-ocean ridge basalt, N-MORB) and was augmented by subducted sediments. Data show that the magma sources of the south OT (SOT) and middle Ryukyu Arc (MRA) basalts were principally influenced by subducted aqueous fluids and bulk sediments, which were potentially added into magma sources by accretion and underplating. At the same time, the magma sources of the middle OT (MOT) and Kobi-syo and Sekibi-Syo (ICBS + SBS) basalts were impacted by subducted aqueous fluids from both altered oceanic crust (AOC) and sediment. The variable geochemical characteristics of these basalts are due to different Wadati-Benioff depths and tectonic environments of formation, while the addition of subducted bulk sediment to SOT and MRA basalts may be due to accretion and underplating, and subsequent to form melange formation, which would occur partial melting after aqueous fluids are added. The addition of AOC and sediment aqueous fluid to MOT and KBS + SBS basalts is therefore the result of cold subducted slab dehydration combined with a rapid subduction rate (82 mm/a), leading to the migration of fluids into the mantle wedge. The presence of these attributes is likely because the OT was a back arc, initial continental marginal sea basin. |
关键词 | Okinawa Trough Th Magmatism Subduction Component Tectonic Environment |
DOI | 10.1016/j.jseaes.2017.05.033 |
收录类别 | SCI |
语种 | 英语 |
WOS记录号 | WOS:000410012200014 |
引用统计 | |
文献类型 | 期刊论文 |
版本 | 出版稿 |
条目标识符 | http://ir.qdio.ac.cn/handle/337002/143126 |
专题 | 海洋地质与环境重点实验室 |
作者单位 | 1.Chinese Acad Sci, Inst Oceanol, Key Lab Marine Geol & Environm, Seafloor Hydrothermal Act Lab, Qingdao 266071, Peoples R China 2.Qingdao Natl Lab Marine Sci & Technol, Lab Marine Mineral Resources, Qingdao 266071, Peoples R China |
第一作者单位 | 中国科学院海洋研究所 |
推荐引用方式 GB/T 7714 | Guo, Kun,Zeng, Zhi-Gang,Chen, Shuai,et al. The influence of a subduction component on magmatism in the Okinawa Trough: Evidence from thorium and related trace element ratios[J]. JOURNAL OF ASIAN EARTH SCIENCES,2017,145:205-216. |
APA | Guo, Kun,Zeng, Zhi-Gang,Chen, Shuai,Zhang, Yu-Xiang,Qi, Hai-Yan,&Ma, Yao.(2017).The influence of a subduction component on magmatism in the Okinawa Trough: Evidence from thorium and related trace element ratios.JOURNAL OF ASIAN EARTH SCIENCES,145,205-216. |
MLA | Guo, Kun,et al."The influence of a subduction component on magmatism in the Okinawa Trough: Evidence from thorium and related trace element ratios".JOURNAL OF ASIAN EARTH SCIENCES 145(2017):205-216. |
条目包含的文件 | ||||||
文件名称/大小 | 文献类型 | 版本类型 | 开放类型 | 使用许可 | ||
The influence of a s(1809KB) | 期刊论文 | 出版稿 | 限制开放 | CC BY-NC-SA | 浏览 |
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。
修改评论