Academic Journal
Genesis and open-system evolution of Quaternary magmas beneath southeastern margin of Tibet: Constraints from Sr-Nd-Pb-Hf isotope systematics
| العنوان: | Genesis and open-system evolution of Quaternary magmas beneath southeastern margin of Tibet: Constraints from Sr-Nd-Pb-Hf isotope systematics |
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| المؤلفون: | Zou, Haibo, Ma, Mingjia, Fan, Qicheng, Xu, Bei, Li, Shuang-Qing, Zhao, Yongwei, King, David T., Jr. |
| المساهمون: | Zou, HB (reprint author), Auburn Univ, Dept Geosci, Auburn, AL 36849 USA., Auburn Univ, Dept Geosci, Auburn, AL 36849 USA., Peking Univ, Sch Earth & Space Sci, Key Lab Orogen Belts & Crustal Evolut, Beijing 100871, Peoples R China., Kunming Univ Sci & Technol, Dept Land Resource Engn, Kunming 650093, Yunnan Province, Peoples R China., China Earthquake Adm, Inst Geol, Beijing 100029, Peoples R China., Univ Sci & Technol China, Sch Earth & Space Sci, Hefei, Peoples R China. |
| المصدر: | SCI |
| بيانات النشر: | LITHOS |
| سنة النشر: | 2017 |
| المجموعة: | Peking University Institutional Repository (PKU IR) / 北京大学机构知识库 |
| مصطلحات موضوعية: | Quaternary volcano, Assimilation fractional crystallization, Tengchong, Continental subduction, indo-Asian collision, TENGCHONG VOLCANIC FIELD, ZIRCON U-PB, TRACE-ELEMENT, MANTLE SOURCE, CRUSTAL STRUCTURE, WESTERN YUNNAN, ULTRAPOTASSIC MAGMATISM, PLATEAU IMPLICATIONS, SOUTHWESTERN CHINA |
| الوصف: | Post-collisional volcanic rocks on the Tibetan Plateau and its margins contain valuable information about the geodynamic processes associated with this Cenozoic continent-continent collision. The Quaternary Tengchong volcanic field at the southeastern margin of the Tibetan Plateau formed high-potassium calc-alkaline volcanic rocks. Herein, we present comprehensive Nd-Sr-Pb-Hf isotopic and elemental data for trachybasalts, basaltic trachyandesites, and trachyandesites from four Quaternary Tengchong volcanoes (Maanshan, Dayingshan, Heikongshan, and Laoguipo) in order to understand their magma genesis and evolution as well as tectonic significance. Good correlations between SiO2 content and the ratios Sr-87/Sr-86, Nd-143/Nd-144. (206)pb/(204)pb, and Hf-177/Hf-176 for these Quaternary volcanics strongly suggest that the combined assimilation and fractional crystallization (AFC) was an important process in the origin of basaltic trachyandesites and trachyandesites. High Y and Yb contents and low Sr/Y ratios of these basaltic trachyandesites and trachyandesites are uncharacteristic of adakites that formed by partial melting of eclogitic lower crust or partial melting of basaltic oceanic crust with eclogite as a restite. A combined assimilation-fractional crystallization model is proposed for these basaltic trachyandesites and trachyandesites. Nd-Sr-Pb-Hf isotopes for the uncontaminated Tengchong magma (trachybasalts with SiO2 < 52.5 wt.% and MgO > 5.5% wt.%) reflect a heterogeneous enriched mantle source. High Th/U, Th/Ta, and Rb/Nb ratios and Nd-Sr-Pb-Hf isotope characteristics of the uncontaminated magmas suggest that the enriched mantle beneath Tengchong formed as a result of subduction of clay-rich sediments, which probably came from the Indian continental plate. Partial melting of the enriched mantle was generated by deep continental subduction coupled with recent regional extension in the Tengchong area. (C) 2016 Elsevier B.V. All rights reserved. ; NSF of China [41272070] ; SCI(E) ; ARTICLE ; 278-290 ; 272 |
| نوع الوثيقة: | journal/newspaper |
| اللغة: | English |
| ردمك: | 978-0-00-393265-2 0-00-393265-6 |
| تدمد: | 0024-4937 1872-6143 |
| Relation: | LITHOS.2017,272,278-290.; 1910033; http://hdl.handle.net/20.500.11897/475498; WOS:000393265600019 |
| DOI: | 10.1016/j.lithos.2016.12.012 |
| الاتاحة: | https://hdl.handle.net/20.500.11897/475498 https://doi.org/10.1016/j.lithos.2016.12.012 |
| رقم الانضمام: | edsbas.B19FF76E |
| قاعدة البيانات: | BASE |
| ردمك: | 9780003932652 0003932656 |
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| تدمد: | 00244937 18726143 |
| DOI: | 10.1016/j.lithos.2016.12.012 |