From crustal anatexis to mantle melting in the Variscan orogen of Corsica (France): SIMS U-Pb zircon age constraints

doi:10.1016/j.tecto.2014.07.021

	From crustal anatexis to mantle melting in the Variscan orogen of Corsica (France): SIMS U-Pb zircon age constraints
	Li, Xian-Hua 1; Faure, Michel 2; Lin, Wei 1
刊名	TECTONOPHYSICS
	2014-11-05
卷号	634 页码:19-30
关键词	Migmatite Granite SIMS U-Pb zircon age Variscan orogen Slab breakoff Corsica
ISSN号	0040-1951
DOI	10.1016/j.tecto.2014.07.021
文献子类	Article
英文摘要	High-precision SIMS U-Pb zircon age determinations are conducted in this study on migmatites and Mg-K magmatic suites from the Variscan orogen of Corsica (France). Zircons from leucosomes of four migmatites yield consistent crystallization ages of ca. 345 Ma. Four Mg-K granitoid rocks and one monzogabbro enclave from the Calvi-Ile Rousse pluton of NW Corsica yield indistinguishable U-Pb zircon ages of ca. 330 Ma. These new SIMS zircon U-Pb dating results indicate that the regional crustal anatexis under amphibolite-facies condition occurred synchronously at ca. 345 Ma throughout the Corsican Variscan chain. There is a ca. 15 m.y. time interval between anatexis of the thickened crust and partial melting of the metasomatized mantle and overlying crust to form the Mg-K rock suites. In combination with the previous dating results for the high-temperature and high-pressure granulite-facies metamorphism, three major discrete tectonothermal events at ca. 360 Ma, ca. 345 Ma, and ca. 330 Ma are acknowledged. We argue for a slab break-off model accounting for thermal and mechanical evolution of the crust within the Variscan orogen of Corsica. A tearing of the subducting oceanic lithosphere initiates the asthenosphere rise to fill the void and causes the granulite-facies metamorphism of the overlying continental crust at ca. 360 Ma. Final breaking of the subducting oceanic lithosphere results in exhumation of the subducted crust to the thickened lower to middle crustal-level. Internal radiogenic heating causes crust-scale migmatization at ca. 345 Ma. Slab break-off and foundering enhance the rise of hot asthenosphere, resulting in conducted thermal perturbation that leads to melting of the metasomatised enriched mantle lithosphere to form Mg-K mafic-granitoid magmatism at ca. 330 Ma. (C) 2014 Elsevier B.V. All rights reserved.
WOS关键词	CONVERGENT PLATE BOUNDARIES ; ANOROGENIC GRANITE GENESIS ; CONTINENTAL-CRUST ; WESTERN CORSICA ; TRACE-ELEMENT ; MINERALOGICAL EVIDENCE ; COLLISIONAL OROGENS ; AFRICAN PROVENANCE ; HERCYNIAN GRANITES ; EVOLUTION
WOS研究方向	Geochemistry & Geophysics
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000345108500002
资助机构	National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070) ; National Natural Science Foundation of China(41273070)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/85514]
专题	中国科学院地质与地球物理研究所
通讯作者	Li, Xian-Hua
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China 2.Univ Orleans, Inst Sci Terre Orleans, F-45067 Orleans 2, France
推荐引用方式 GB/T 7714	Li, Xian-Hua,Faure, Michel,Lin, Wei. From crustal anatexis to mantle melting in the Variscan orogen of Corsica (France): SIMS U-Pb zircon age constraints[J]. TECTONOPHYSICS,2014,634:19-30.
APA	Li, Xian-Hua,Faure, Michel,&Lin, Wei.(2014).From crustal anatexis to mantle melting in the Variscan orogen of Corsica (France): SIMS U-Pb zircon age constraints.TECTONOPHYSICS,634,19-30.
MLA	Li, Xian-Hua,et al."From crustal anatexis to mantle melting in the Variscan orogen of Corsica (France): SIMS U-Pb zircon age constraints".TECTONOPHYSICS 634(2014):19-30.