气候变化领域集成服务门户(CCPortal): Regional-scale polydiapirism predating the Neoarchean Yilgarn Orogeny

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DOI	10.1016/j.tecto.2020.228375
	Regional-scale polydiapirism predating the Neoarchean Yilgarn Orogeny
	Zibra I.; Lu Y.; Clos F.; Weinberg R.F.; Peternell M.; Wingate M.T.D.; Prause M.; Schiller M.; Tilhac R.
发表日期	2020
ISSN	00401951
卷号	779
英文摘要	Gneiss domes occur in a wide variety of orogenic and anorogenic domains of the continental crust, and play a major role in lithosphere dynamics by allowing upwards transfer of heat and mass. They commonly contain a core of granites and/or migmatites, overlain by a mantle of lower-grade rocks. Evolutionary models of many gneiss domes are controversial. Here we use new structural and zircon isotopic data to unravel the tectono-magmatic evolution of the Yalgoo dome and surroundings, at the margins of the Neoarchean Yilgarn Orogen, Western Australia. The study area includes at least seven granite–migmatite domes (5–70 km in average diameter), and several subdomes within the larger domes, all showing comparable structural features and age. In each dome, a concentric domal foliation is concordant with granite–greenstone contacts, bearing a radial, outward-plunging lineation. The bulk of the structures in each dome reflect magmatic flow, with pervasive subsolidus fabrics occurring only along the outer dome margins, and reflecting dome-up kinematics. Narrow greenstone keels pinched between domes and subdomes display vertical constriction, in an area regionally dominated by flattening along the steep sides of the deeply-eroded domes, and along the flat-laying dome roofs. The regional structural pattern and the kinematics of the high-strain zones are best explained by sequential emplacement of nested diapirs, which delivered large volumes of granitic magma in a c. 20 Myr time-span. The dome-and-keel regional architecture and the internal structures of each dome resulted therefore from multiscale polydiapirism. These diapirs were later weakly overprinted by a tectonic fabric that developed during the Neoarchean Yilgarn Orogeny. The contrast between the Yalgoo region and the rest of the craton, which was strongly reworked by this orogeny, highlights the dichotomy of tectonic styles in Archean terranes, demonstrating that diapirism dominated in times of tectonic quiescence. © 2020
关键词	Microstructures Quartz crystallographic preferred orientation Structural geology Tectonics Zircon isotopes
英文关键词	Domes; Economic geology; Granite; Isotopes; Kinematics; Microstructure; Silicate minerals; Tectonics; Zircon; Continental crusts; Crystallographic preferred orientations; Evolutionary models; Lithosphere dynamics; Regional architectures; Structural feature; Structural pattern; Zircon isotope; Structural geology; continental crust; crustal structure; diapirism; isotopic composition; microstructure; structural geology; tectonic setting; zircon; Australia; Western Australia; Yilgarn Block
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/207920
作者单位	Geological Survey of Western Australia, 100 Plain Street, East Perth, Western Australia 6004, Australia; School of Earth, Atmosphere and Environment, Monash University, Clayton, VIC 3800, Australia; Centre for Exploration Targeting and Australian Research Council Centre of Excellence for Core to Crust Fluid Systems (CCFS), School of Earth Sciences, The University of Western Australia, Crawley, WA 6009, Australia; Department of Earth Sciences, University of Gothenburg, Box 460, Gothenburg, 405 30, Sweden; Eberhard Karls Universität Tübingen Geschwister-Scholl-Platz, Tübingen, 72074, Germany; ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) and GEMOC, Department of Earth and Planetary Sciences, Macquarie University, Sydney, NSW 2109, Australia
推荐引用方式 GB/T 7714	Zibra I.,Lu Y.,Clos F.,et al. Regional-scale polydiapirism predating the Neoarchean Yilgarn Orogeny[J],2020,779.
APA	Zibra I..,Lu Y..,Clos F..,Weinberg R.F..,Peternell M..,...&Tilhac R..(2020).Regional-scale polydiapirism predating the Neoarchean Yilgarn Orogeny.Tectonophysics,779.
MLA	Zibra I.,et al."Regional-scale polydiapirism predating the Neoarchean Yilgarn Orogeny".Tectonophysics 779(2020).