Variations in the geochemical structure of the mantle wedge beneath the northeast Asian marginal region from pre- to post-opening of the Japan Sea
Variations in the geochemical structure of the mantle wedge beneath the northeast Asian marginal region from pre- to post-opening of the Japan Sea
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日本海打开前后东北亚边缘区地幔楔地球化学结构的变化
DOI：
10.1016/j.lithos.2015.03.008
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发表时间：
2015-05
期刊：
影响因子：
3.5
通讯作者：
Sun Chun-qing
中科院分区：
文献类型：
--
作者：
Chen Shuang-shuang;Liu Jia-qi;Chen Sheng-sheng;Guo Zheng-fu;Sun Chun-qing
东北亚边缘地区的深部软流圈过程和岩浆活动的动力学机制是一个重要的问题，但一直难以详细研究。通过对日本海玄武岩的岩相学、全岩常量元素和微量元素、Sr-Nd-Pb同位素组成、K-Ar年代学等综合研究，结合前人的研究成果，探讨了东北亚地区的构造演化。日本海玄武岩属钙碱性系列，具有重稀土元素平坦、Ba、Sr、Pb显著正异常和Eu（δEu = 0.81-1.21）轻微异常的特征，可分为794站上下层（US 794、LS 794）和797站上下层（US 797、LS 797）。US 797样品组LREE、LILE较低，放射性同位素相对贫化（87 Sr/86 Sr = 0.704051-0.704254; 143 Nd/144 Nd = 0.513035-0.513139; 206 Pb/204 Pb = 17.758-18.223），而样品组LS 797，US 794，LS 794的不相容元素含量较高，同位素值略富集（87Sr/86Sr = 0.704248-0.705222;143Nd/144Nd = 0.512705-0.512917;206Pb/204Pb = 18.077-18.377）。LS 797、US 794和LS 794样品的K-Ar和40 Ar-39 Ar年代学数据表明，它们的年龄范围为17.7 ± 0.5-21.2 ± 0.8Ma，明显大于US 797样品的年龄范围（15.1 ± 0.9-17.2 ± 0.7Ma）。本文的研究结果与其它资料相结合，显示出日本海、日本东北部弧后侧和北海道西南部、北海道北部的Sikhote-Alin新生代玄武岩在23-24 Ma（17 ± 2 Ma）的Sr-Nd同位素变化特征（15-19 Ma）、15 Ma和> 12 Ma，表明东北亚地区软流圈上涌相对于岩石圈向东推进。我们认为，东北亚边缘地区玄武质岩浆源区的时空变化与日本海的伸展作用密切相关。
Deep asthenospheric processes and the dynamic mechanism of magmatism in the northeast Asian marginal region are of significant interest but have been difficult to study in detail. We completed comprehensive studies on Japan Sea basalts including petrography, whole-rock major and trace elements, Sr–Nd–Pb isotopic compositions, and K–Ar geochronology, then combined our results with previous research to study the tectonic evolution of northeast Asia. The Japan Sea basalts, divided into Upper and Lower layers of Site 794 (US794, LS794), and Upper and Lower layers of Site 797 (US797, LS797) based on their stratigraphic level, belong to the calc-alkalic series and are characterized by flat HREE with significantly positive anomalies of Ba, Sr, and Pb, and slight anomalies of Eu (δEu = 0.81–1.21). The US797 sample group has lower LREE, LILE and relatively depleted radioactive isotope ratios (87Sr/86Sr = 0.704051–0.704254;143Nd/144Nd = 0.513035–0.513139;206Pb/204Pb = 17.758–18.223), whereas the sample groups LS797, US794, and LS794 have relatively higher incompatible elements and slightly enriched isotopic values (87Sr/86Sr = 0.704248–0.705222;143Nd/144Nd = 0.512705–0.512917;206Pb/204Pb = 18.077–18.377) due to the involvement of Pacific subducted fluid and sediments. K–Ar and40Ar–39Ar geochronological data indicate age ranges of LS797, US794, and LS794 samples of 17.7 ± 0.5–21.2 ± 0.8 Ma, significantly older than those of US797 (15.1 ± 0.9–17.2 ± 0.7 Ma). Our data compiled with other data show sharply defined Sr–Nd isotopic variations of the Cenozoic basalts from Sikhote-Alin, the Japan Sea, the back-arc side of NE Japan and SW Hokkaido, and north Hokkaido from a slightly enriched to a depleted isotopic signature at 23–24 Ma, 17 ± 2 Ma (15–19 Ma), 15 Ma, and > 12 Ma, respectively, indicating that the upwelling asthenosphere beneath northeast Asia progressed eastward relative to the lithosphere. We conclude that the temporal and spatial variations of basaltic magma sources in the northeast Asian marginal region are closely associated with the extension of the Japan Sea.
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影响因子：
3.9
作者：
FREY, FA;GREEN, DH;ROY, SD
通讯作者：
ROY, SD
DOI：
10.1144/gsl.sp.1984.016.01.05
发表时间：
1984
期刊：
Geological Society, London, Special Publications
影响因子：
--
作者：
A. Saunders;J. Tarney
通讯作者：
A. Saunders;J. Tarney
影响因子：
0.8
作者：
J. Ohki;K. Shuto;H. Kagami
通讯作者：
J. Ohki;K. Shuto;H. Kagami
影响因子：
5.3
作者：
A. Volpe;J. Macdougall;G. W. Lugmair;J. Hawkins;P. Lonsdale
通讯作者：
A. Volpe;J. Macdougall;G. W. Lugmair;J. Hawkins;P. Lonsdale
影响因子：
5
作者：
M. Tatsumoto;Yoichi Nakamura
通讯作者：
M. Tatsumoto;Yoichi Nakamura