| 冲绳海槽玄武岩玻璃主量、微量元素地球化学特征 |
| |
| 引用本文： | 国坤,翟世奎,于增慧,曾志刚,王晓媛,殷学博.冲绳海槽玄武岩玻璃主量、微量元素地球化学特征[J].海洋学报(英文版),2018,37(2):14-24. |
| |
| 作者姓名： | 国坤 翟世奎 于增慧 曾志刚 王晓媛 殷学博 |
| |
| 作者单位： | 中国科学院海洋研究所 海洋地质与环境重点实验室, 山东 青岛 266071;青岛海洋科学与技术国家实验室 海洋地质过程与环境功能实验室, 山东 青岛 266000;中国海洋大学 海底科学与探测技术教育部重点实验室, 山东 青岛 266100,中国海洋大学 海底科学与探测技术教育部重点实验室, 山东 青岛 266100,中国海洋大学 海底科学与探测技术教育部重点实验室, 山东 青岛 266100,中国科学院海洋研究所 海洋地质与环境重点实验室, 山东 青岛 266071,中国科学院海洋研究所 海洋地质与环境重点实验室, 山东 青岛 266071,中国科学院海洋研究所 海洋地质与环境重点实验室, 山东 青岛 266071 |
| |
| 基金项目： | The National Basic Research Program of China under contract No. 2013CB429702; the open fund project supported by the Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology under contract No. MGQNLM-KF201707; the National Natural Science Foundation of China under contract Nos 41476044, 41325021 and 41306053; the Special Fund for the Taishan Scholar Program of Shandong Province under contract No. ts201511061; the AoShan Talents Program supported by Qingdao National Laboratory for Marine Science and Technology under contract No. 2015ASTP-0S17; the Innovative Talent Promotion Program under contract No. 2012RA2191; the Science and Technology Development Program of Shandong Province under contract No. 2013GRC31502. |
| |
| 摘 要： | The Okinawa Trough(OT) is a back-arc basin at an initial spreading stage that is under the influence of subduction of the Philippine Sea Plate. In this study, we analyzed the geochemical compositions of basaltic glass in the OT and discussed the effects of different magmatic sources, evolution, and subducted components in basalts. Our results showed that the middle and southern regions of the OT exhibit characteristics consistent with an iron-rich tholeiite series. Trace element proportions conform to the typical spider diagram pattern characteristic of back-arc basin basalts, rich in large ion lithophile elements(LILEs) including Rb, Ba, Pb, U, and Th, while depleted in high field-strength elements(HFSEs) including Nb, Ta, Zr, Hf, and Ti. The distribution of rare earth elements(REEs) is also consistent with enrichment by right-leaning light rare earth elements(LREEs).The addition of enriched mantle type I(EMI) materials as well as mantle heterogeneity may have led to variable degrees of enrichment in different regions. The magma source of the middle trough has undergone crystallization towards pyroxene, while development of plagioclase was restricted partly, and the crystallization of spinel and olivine ceased altogether. At the same time, crystallization of the southern OT magma source was dominated by olivine and including the formation of plagioclase, pyroxene, and magnetite(or titanomagnetite). Finally, the results of this study showed that 90% Th, 95% Ba in the southern basalt, 50%–70% Th and 70%–90% Ba in the middle basalt originated from subducted component. Different subducted component influence may be due to different subduction zone structural feature.
|
| 关 键 词： | 冲绳海槽 玄武岩玻璃 地球化学 岩浆演化 俯冲组分 |
| 收稿时间： | 2017/1/5 0:00:00 |
| 修稿时间： | 2011/2/24 0:00:00 |
Geochemical characteristics of major and trace elements in the Okinawa Trough basaltic glass |
| |
| GUO Kun,ZHAI Shikui,YU Zenghui,ZENG Zhigang,WANG Xiaoyuan and YIN Xuebo.Geochemical characteristics of major and trace elements in the Okinawa Trough basaltic glass[J].Acta Oceanologica Sinica,2018,37(2):14-24. |
| |
| Authors: | GUO Kun ZHAI Shikui YU Zenghui ZENG Zhigang WANG Xiaoyuan and YIN Xuebo |
| |
| Affiliation: | Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China;Key Laboratory of Submarine Geosciences and Prospection of Ministry of Education, Ocean University of China, Qingdao 266100, China,Key Laboratory of Submarine Geosciences and Prospection of Ministry of Education, Ocean University of China, Qingdao 266100, China,Key Laboratory of Submarine Geosciences and Prospection of Ministry of Education, Ocean University of China, Qingdao 266100, China,Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China,Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China and Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China |
| |
| Abstract: | The Okinawa Trough (OT) is a back-arc basin at an initial spreading stage that is under the influence of subduction of the Philippine Sea Plate. In this study, we analyzed the geochemical compositions of basaltic glass in the OT and discussed the effects of different magmatic sources, evolution, and subducted components in basalts. Our results showed that the middle and southern regions of the OT exhibit characteristics consistent with an iron-rich tholeiite series. Trace element proportions conform to the typical spider diagram pattern characteristic of back-arc basin basalts, rich in large ion lithophile elements (LILEs) including Rb, Ba, Pb, U, and Th, while depleted in high field-strength elements (HFSEs) including Nb, Ta, Zr, Hf, and Ti. The distribution of rare earth elements (REEs) is also consistent with enrichment by right-leaning light rare earth elements (LREEs). The addition of enriched mantle type I (EMI) materials as well as mantle heterogeneity may have led to variable degrees of enrichment in different regions. The magma source of the middle trough has undergone crystallization towards pyroxene, while development of plagioclase was restricted partly, and the crystallization of spinel and olivine ceased altogether. At the same time, crystallization of the southern OT magma source was dominated by olivine and including the formation of plagioclase, pyroxene, and magnetite (or titanomagnetite). Finally, the results of this study showed that 90% Th, 95% Ba in the southern basalt, 50%-70% Th and 70%-90% Ba in the middle basalt originated from subducted component. Different subducted component influence may be due to different subduction zone structural feature. |
| |
| Keywords: | Okinawa Trough basaltic glass geochemistry magmatic evolution subducted component |
| 本文献已被 CNKI SpringerLink 等数据库收录！ |
| 点击此处可从《海洋学报(英文版)》浏览原始摘要信息 |
|
点击此处可从《海洋学报(英文版)》下载全文 |
|
