中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Recycling of deeply subducted continental crust in the Dabie Mountains, central China

文献类型:期刊论文

作者Huang, Fang; Li, Shuguang; Dong, Feng; Li, Qiuli; Chen, Fukun; Wang, Ying; Yang, Wei
刊名LITHOS
出版日期2007-06-01
卷号96期号:1-2页码:151-169
关键词Dabie-Sulu orogen crust/mantle interaction post-collisional magmatism
ISSN号0024-4937
DOI10.1016/j.lithos.2006.09.019
文献子类Article
英文摘要Post-collisional mafic-ultramafic intrusive rocks from the North Dabie zone show evidence for derivation from a mantle source that was overprinted by partial melts derived from subducted crust of the South China Block. All the samples are characterized by enrichment of large ion lithophile elements (LILE, e.g., Ba, Th) and depletion of high field strength elements (HFSE, e.g., Nb, Ti). The Zhujiapu intrusion developed in the North Dabie zone has moderately enriched Sr-87/Sr-86(i) (0.70605-0.70827), negative epsilon(Nd)(T) values (-2.3 to -18.8), and unradiogenic Pb isotopes. Such typical "continental" geochemical features do not result from crustal contamination or magma mixing, but reflect the properties of the mantle source. Because the trace element and Sr-Nd isotopic compositions of the post-collisional mafic-ultramafic intrusive rocks from the North Dabie zone are similar to those of the Mesozoic mantle-derived rocks and lower crust granulites and xenoliths from the North China Block, it is unclear whether the "continental" features are due to the contribution of lithospheric mantle and lower crust from the North China Block or deeply subducted materials from the South China Block. However, for a given Pb-206/Ph-204(i) or Delta 7/4, the Pb-208/Pb-204(i) or Delta 8/4 (159-180) of the post-collisional mafic-ultramafic intrusive rocks from the North Dabie zone is close to the Mesozoic granitoids, eclogites, and gray gneisses from the Dabie-Sulu orogen, but significantly higher than the Mesozoic mantle-derived rocks and lower crust granulites and xenoliths from the North China Block (Delta 8/4 < 160). This indicates that the subducted slabs of the South China Block experienced a higher time-integrated Th/U but similar U/Pb as the deep lithosphere of the North China Block. We therefore propose that the mantle source of the post-collisional mafic-ultramafic intrusive rocks from the Dabie-Sulu orogen result from the depleted upper mantle metasomatised by melts from recycled deeply subducted crust. Due to the continent-continent collision between the South China Block and North China Block in the late Triassic, the lithosphere of the Dabie orogen was over-thickened resulting in eclogitic metamorphism in the mafic lower crust, producing a gravitational instability. The subducted eclogitic lower crust foundered and was recycled into the upper mantle beneath the orogen, resulting in mountain root removal, less mafic composition of unusually evolved continental crust, and upper mantle heterogeneity. (C) 2006 Elsevier B.V All rights reserved.
WOS关键词LITHOSPHERIC MANTLE BENEATH ; PB ISOTOPIC COMPOSITIONS ; EAST-CENTRAL CHINA ; MAFIC-ULTRAMAFIC INTRUSIONS ; TRACE-ELEMENT GEOCHEMISTRY ; OCEAN ISLAND BASALTS ; SULU OROGENIC BELT ; NORTH CHINA ; SOUTH-CHINA ; METAMORPHIC ROCKS
WOS研究方向Geochemistry & Geophysics ; Mineralogy
语种英语
WOS记录号WOS:000247167300010
出版者ELSEVIER SCIENCE BV
源URL[http://ir.iggcas.ac.cn/handle/132A11/67310]  
专题中国科学院地质与地球物理研究所
通讯作者Huang, Fang
作者单位1.Univ Illinois, Dept Geol, Urbana, IL 61801 USA
2.Univ Sci & Technol China, Dept Earth & Space Sci, CAS Key Lab Crust Mantle Mat & Environm, Hefei 230026, Anhui, Peoples R China
3.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China
推荐引用方式
GB/T 7714
Huang, Fang,Li, Shuguang,Dong, Feng,et al. Recycling of deeply subducted continental crust in the Dabie Mountains, central China[J]. LITHOS,2007,96(1-2):151-169.
APA Huang, Fang.,Li, Shuguang.,Dong, Feng.,Li, Qiuli.,Chen, Fukun.,...&Yang, Wei.(2007).Recycling of deeply subducted continental crust in the Dabie Mountains, central China.LITHOS,96(1-2),151-169.
MLA Huang, Fang,et al."Recycling of deeply subducted continental crust in the Dabie Mountains, central China".LITHOS 96.1-2(2007):151-169.

入库方式: OAI收割

来源:地质与地球物理研究所

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