气候变化领域集成服务门户(CCPortal): A ductile extensional shear zone at the contact area between HP-LT metamorphic units in the Talea Ori; central Crete; Greece: deformation during early stages of exhumation from peak metamorphic conditions

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DOI	10.1007/s00531-018-1650-6
	A ductile extensional shear zone at the contact area between HP-LT metamorphic units in the Talea Ori; central Crete; Greece: deformation during early stages of exhumation from peak metamorphic conditions
	Seybold L.; Trepmann C.A.; Janots E.
发表日期	2019
ISSN	14373254
起始页码	213
结束页码	227
卷号	108 期号:1
英文摘要	We report on an extensional ductile shear zone in central Crete at the contact area between the high-pressure low-temperature (HP-LT) metamorphic Phyllite-Quartzite unit sensu stricto (PQ s.str.) and the Talea Ori group (Plattenkalk unit). Mapping and microscopic analysis along the 20 km long contact reveal extensional shear bands, shear band cleavages (C′-type) and associated quartz veins in both units, occurring over a width of up to a kilometer. The shear offset along the shear bands is systematically perpendicular to the contact with the hanging block (PQ s.str.) being downfaulted. Abundant discordant quartz veins are associated to shear band boundaries, asymmetric boudinage and foliation boudinage, forming m-wide vein networks. These mesoscopic deformation structures together with related microstructures such as strain shadows, growth rims of albite porphyroblasts and stylolites indicate dissolution–precipitation creep as main deformation mechanism accompanied by vein formation. Temperatures during deformation are indicated to be close to peak metamorphic temperatures (≥ 300–350 °C) by the growth rims of albite porphyroblasts and micas present in the shear band cleavages, which are consistent with quartz vein microstructures showing subgrains and sutured high angle grain boundaries. Peak metamorphic temperatures inferred by the degree of graphitization of carbonaceous material are similar in the hanging wall and the footwall of the shear zone, which is consistent with fast and nearly adiabatic exhumation. Our study demonstrates the importance of ductile shear zones with high strain rate dissolution–precipitation creep and vein formation in HP-LT metamorphic rocks for the early exhumation history. © 2018, The Author(s).
英文关键词	Albite; Dissolution–precipitation creep; Exhumation; Plattenkalk; PQ s.str; Shear bands
语种	英语
scopus关键词	albite; creep; deformation; exhumation; metamorphism; precipitation (chemistry); shear band; shear zone; Aegean Islands; Crete [Greece]; Greece
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/147886
作者单位	Ludwig-Maximilians-Universität, Luisenstraße 37, Munich, 80333, Germany; Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, Grenoble, 38000, France
推荐引用方式 GB/T 7714	Seybold L.,Trepmann C.A.,Janots E.. A ductile extensional shear zone at the contact area between HP-LT metamorphic units in the Talea Ori; central Crete; Greece: deformation during early stages of exhumation from peak metamorphic conditions[J],2019,108(1).
APA	Seybold L.,Trepmann C.A.,&Janots E..(2019).A ductile extensional shear zone at the contact area between HP-LT metamorphic units in the Talea Ori; central Crete; Greece: deformation during early stages of exhumation from peak metamorphic conditions.International Journal of Earth Sciences,108(1).
MLA	Seybold L.,et al."A ductile extensional shear zone at the contact area between HP-LT metamorphic units in the Talea Ori; central Crete; Greece: deformation during early stages of exhumation from peak metamorphic conditions".International Journal of Earth Sciences 108.1(2019).