气候变化领域集成服务门户(CCPortal): Syn-deformational melt percolation through a high-pressure orthogneiss and the exhumation of a subducted continental wedge (Orlica-Śnieżnik Dome; NE Bohemian Massif)

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DOI	10.1007/s00531-020-01838-4
	Syn-deformational melt percolation through a high-pressure orthogneiss and the exhumation of a subducted continental wedge (Orlica-Śnieżnik Dome; NE Bohemian Massif)
	Aguilar C.; Štípská P.; Chopin F.; Schulmann K.; Pitra P.; Závada P.; Hasalová P.; Martelat J.-E.
发表日期	2020
ISSN	14373254
起始页码	1213
结束页码	1246
卷号	109 期号:4
英文摘要	High-pressure granitic orthogneiss of the south-eastern Orlica–Śnieżnik Dome (NE Bohemian Massif) shows relics of a shallow-dipping foliation, reworked by upright folds and a mostly pervasive N–S trending subvertical axial planar foliation. Based on macroscopic observations, a gradual transition from banded to schlieren and nebulitic orthogneiss was distinguished. All rock types comprise plagioclase, K-feldspar, quartz, white mica, biotite and garnet. The transition is characterized by increasing presence of interstitial phases along like-like grain boundaries and by progressive replacement of recrystallized K-feldspar grains by fine-grained myrmekite. These textural changes are characteristic for syn-deformational grain-scale melt percolation, which is in line with the observed enrichment of the rocks in incompatible elements such as REEs, Ba, Sr and K suggesting open-system behaviour with melt passing through the rocks. The P–T path deduced from the thermodynamic modelling indicates decompression from ~ 15−16 kbar and ~ 650–740 ºC to ~ 6 kbar and ~ 640 ºC. Melt was already present at the P–T peak conditions as indicated by the albitic composition of plagioclase in films, interstitial grains and in myrmekite. The variably re-equilibrated garnet suggests that melt content may have varied along the decompression path, involving successively both melt gain and loss. The ~ 6–8 km wide zone of vertical foliation and migmatite textural gradients is interpreted as vertical crustal-scale channel where the grain-scale melt percolation was associated with horizontal shortening and vertical flow of partially molten crustal wedge en masse. © 2020, Geologische Vereinigung e.V. (GV).
英文关键词	Exhumation; HP-granitic orthogneiss; Melt percolation; Petrological modelling
语种	英语
scopus关键词	deformation; enrichment; exhumation; high pressure; melt; orthogneiss; percolation; subduction; tectonic wedge; texture; thermodynamics; Bohemian Massif
来源期刊	International Journal of Earth Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/147677
作者单位	Centre for Lithospheric Research, Czech Geological Survey, Klárov 3, Prague, 11821, Czech Republic; Université de Strasbourg, CNRS, IPGR UMR 7516, Strasbourg, 67000, France; Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, Rennes, 35000, France; Institute of Geophysics, Academy of Sciences, Boční II/1401, Prague, 14131, Czech Republic; Laboratoire de Géologie de Lyon–CNRS UMR5276, Université Claude Bernard et École Normale Supérieure, Villeurbanne, 69622, France
推荐引用方式 GB/T 7714	Aguilar C.,Štípská P.,Chopin F.,et al. Syn-deformational melt percolation through a high-pressure orthogneiss and the exhumation of a subducted continental wedge (Orlica-Śnieżnik Dome; NE Bohemian Massif)[J],2020,109(4).
APA	Aguilar C..,Štípská P..,Chopin F..,Schulmann K..,Pitra P..,...&Martelat J.-E..(2020).Syn-deformational melt percolation through a high-pressure orthogneiss and the exhumation of a subducted continental wedge (Orlica-Śnieżnik Dome; NE Bohemian Massif).International Journal of Earth Sciences,109(4).
MLA	Aguilar C.,et al."Syn-deformational melt percolation through a high-pressure orthogneiss and the exhumation of a subducted continental wedge (Orlica-Śnieżnik Dome; NE Bohemian Massif)".International Journal of Earth Sciences 109.4(2020).