Compressional origin of the Aegean Orogeny,Greece
Compressional origin of the Aegean Orogeny, Greece作者机构:Dept Earth SciencesOxford UniversitySouth Parks RoadOxfordOX13ANUK School of Earth and Environmental SciencesUniversity of St AndrewsSt AndrewsKY169ALUK
出 版 物:《Geoscience Frontiers》 (地学前缘(英文版))
年 卷 期:2022年第13卷第2期
页 面:383-404页
核心收录:
学科分类:070904[理学-构造地质学] 0709[理学-地质学] 070901[理学-矿物学、岩石学、矿床学] 07[理学] 0708[理学-地球物理学] 0704[理学-天文学]
基 金:Natural Environment Research Council grant NE/L0021612/1 NERC Isotope Geoscience Laboratory grant IP-1597-1115 for funding
主 题:Cyclades Ophiolite High-pressure metamorphism Core complex Compressional tectonics
摘 要:The Aegean Sea area is thought to be an actively extending back-arc region,north of the present day Hellenic volcanic arc and north-dipping subduction zone in the Eastern *** area shows extensive normal faulting,ductile‘extensional’shear zones and extensional S-C fabrics throughout the islands that have previously been related to regional Aegean extension associated with slab rollback on the Hellenic Subduction *** this paper,we question this interpretation,and suggest the Cenozoic geodynamic evolution of the Aegean region is associated with a Late Cretaceous-Eocene NE-dipping subduction zone that was responsible for continentcontinent collision between Eurasia and Adria-Apulia/*** of eclogite and blueschist facies rocks in the Cyclades and kyanite-sillimanite grade gneisses in the Naxos core complex have pressures that are far greater than could be accounted for purely by lithospheric extension and isostatic *** identify four stages of crustal shortening that affected the region prior to regional lithospheric extension,herein called the Aegean *** orogeny followed a classic Wilson cycle from early ophiolite obduction(ca.74 Ma)onto a previously passive continental margin,to attempted crustal subduction with HP eclogite and blueschist facies metamorphism(ca.54-45 Ma),through crustal thickening and regional kyanite-sillimanite grade Barroviantype metamorphism(ca.22-14 Ma),to orogenic collapse(14 Ma).At least three periods of‘extensional’fabrics relate to:(1)Exhumation of blueschists and eclogite facies rocks showing tight-isoclinal folds and top-NE,base-SW fabrics,recording return flow along a subduction channel in a compressional tectonic setting(ca.50-35 Ma).(2)Extensional fabrics within the core complexes formed by exhumation of kyanite-and sillimanite gneisses showing thrust-related fabrics at the base and‘extensional’fabrics along the top(ca.18.5-14 Ma).(3)Regional ductile-brittle‘extensional’fabrics and low-angle