气候变化领域集成服务门户(CCPortal): Plate tectonics and mantle controls on plume dynamics

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DOI	10.1016/j.epsl.2020.116439
	Plate tectonics and mantle controls on plume dynamics
	Arnould M.; Coltice N.; Flament N.; Mallard C.
发表日期	2020
ISSN	0012821X
卷号	547
英文摘要	Mantle plumes provide valuable information about whole-mantle convection: they originate at the core-mantle boundary, cross Earth's mantle and interact with the lithosphere. For instance, it has been proposed that the mobility/stability of plumes depends on plume intrinsic properties, on how slabs interact with the basal boundary layer, on mantle flow, or on their proximity to mid-ocean ridges. Here, we use 3D-spherical models of mantle convection generating self-consistent plate-like behaviour to investigate the mechanisms linking tectonics and mantle convection to plume dynamics. Our models produce fully-dynamic mantle plumes that rise vertically with deflection <10° and present excess temperatures, rising speeds, buoyancy and heat fluxes comparable to observations. In the absence of plate tectonics, plumes are stable and their lifetime exceeds hundreds of million years. With plate tectonics, plumes are more mobile, and we identify four physical mechanisms controlling their stability. 1/ Fixed plumes are located at saddle points of basal mantle flow. 2/ Plumes moving at speeds between 0.5-1 cm yr−1 are slowly entrained by passive mantle flow. 3/ Fast plume motions between 2-5 cm yr−1 lasting several tens of million years are caused by slab push. 4/ Plumes occasionally drift at speeds >5 cm yr−1 over <10 Myr through plume merging. We do not observe systematic anchoring of plumes to mid-oceanic ridges. Independent of the presence of a dense basal layer, plate-like regimes decrease the lifetime of plumes compared to stagnant-lid models. Plume age, temperature excess or buoyancy flux are not diagnostic of plume lateral speed. The fraction of plumes moving by less than 0.5 cm yr−1 is >25%, which suggests that fixed hotspot reference frames can be defined from carefully selected hotspot tracks. © 2020 Elsevier B.V.
关键词	mantle convection Mantle plumes numerical modelling plate-like tectonics plume drift
英文关键词	Boundary layers; Buoyancy; Structural geology; Thermal plumes; Core-mantle boundary; Intrinsic property; Mantle convection; Mid oceanic ridges; Mid-ocean ridges; Physical mechanism; Reference frame; Spherical models; Tectonics; core-mantle boundary; hot spot; mantle convection; mantle plume; mantle process; mantle structure; mid-ocean ridge; plate tectonics; structural control; tectonic setting; three-dimensional modeling
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202473
作者单位	Laboratoire de Géologie, École Normale Supérieure, CNRS UMR 8538, PSL Research University, 24 rue Lhomond, Paris, 75005, France; Université de Lyon, École Normale Supérieure de Lyon, Université Claude Bernard, Laboratoire de Géologie de Lyon, Terre, Planètes, Environnement, CNRS UMR 5276, 2 rue Raphaël Dubois, Villeurbanne, 69622, France; EarthByte Group, School of Geosciences, The University of Sydney, NSW, 2006, Australia; Centre for Earth Evolution and Dynamics, Department of Geosciences, University of Oslo, Oslo, 0371, Norway; GeoQuEST Research Centre, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia
推荐引用方式 GB/T 7714	Arnould M.,Coltice N.,Flament N.,et al. Plate tectonics and mantle controls on plume dynamics[J],2020,547.
APA	Arnould M.,Coltice N.,Flament N.,&Mallard C..(2020).Plate tectonics and mantle controls on plume dynamics.Earth and Planetary Science Letters,547.
MLA	Arnould M.,et al."Plate tectonics and mantle controls on plume dynamics".Earth and Planetary Science Letters 547(2020).