气候变化领域集成服务门户(CCPortal): Precambrian deformation belts in compressive tectonic regimes: A numerical perspective

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DOI	10.1016/j.tecto.2020.228350
	Precambrian deformation belts in compressive tectonic regimes: A numerical perspective
	Poh J.; Yamato P.; Duretz T.; Gapais D.; Ledru P.
发表日期	2020
ISSN	00401951
卷号	777
英文摘要	The thermal state of the lithosphere is often considered as the main factor controlling the distribution of the structural and metamorphic features in tectonic systems (ancient versus modern tectonics). Deformation in ancient (weak and hot) lithospheres is distributed whereas deformation in modern (strong and cold) lithospheres is localised into prominent shear zones. The distributed deformation during the Precambrian suggests lower compressive strain rates are required, implying a long compression duration. However, the effects of variable strain rate on the compression of ancient lithospheres remain under-explored. A series of numerical models mimicking Precambrian lithospheric conditions is proposed and a broad range of thermal profiles and shortening rates is tested to investigate their influence on the resultant deformation modes. Two broad deformation styles were found to be significantly influenced by the magnitude of the shortening rates and stand out from the parametric study: (i) pop-downs and upper crustal thrusting at high strain rates that favour the formation of shear zones, and (ii) sedimentary cusping deformation at slower strain rates that generates well-defined vertical finite strain patterns. These two deformation modes were compared with natural examples, providing further insight into the evolution of their respective deformations. The vertical structures at the Hearne Craton (western Canadian Shield) could be explained via the sedimentary cusping mechanism by constraining our models with available geological data. Meanwhile, the vertical finite strain patterns from the proposed reference model now provide a tectonic template for future fluid-thermal convection simulations, to predict fluid flow and mineralisation potential. © 2020
关键词	Ancient structures Precambrian tectonics Rheology of the lithosphere
英文关键词	Deformation; Flow of fluids; Heat convection; Sedimentology; Structural geology; Tectonics; Ancient structures; Compressive strain rate; Distributed deformation; Precambrian; Reference modeling; Resultant deformation; Thermal convections; Vertical structures; Strain rate; deformation; lithosphere; numerical model; Precambrian; rheology; shear zone; strain rate; tectonics; upper crust; Canadian Shield
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/207849
作者单位	Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, Rennes, 35000, France; Institut Universitaire de France (IUF), France; Orano Canada Inc., Saskatoon, Canada
推荐引用方式 GB/T 7714	Poh J.,Yamato P.,Duretz T.,et al. Precambrian deformation belts in compressive tectonic regimes: A numerical perspective[J],2020,777.
APA	Poh J.,Yamato P.,Duretz T.,Gapais D.,&Ledru P..(2020).Precambrian deformation belts in compressive tectonic regimes: A numerical perspective.Tectonophysics,777.
MLA	Poh J.,et al."Precambrian deformation belts in compressive tectonic regimes: A numerical perspective".Tectonophysics 777(2020).