气候变化领域集成服务门户(CCPortal): Convective tipping point initiates localization of basaltic fissure eruptions

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DOI	10.1016/j.epsl.2020.116637
	Convective tipping point initiates localization of basaltic fissure eruptions
	Jones T.J.; Llewellin E.W.
发表日期	2021
ISSN	0012821X
卷号	553
英文摘要	Basaltic fissure eruptions may evolve rapidly and unpredictably complicating hazard management. Localization of an elongate fissure to one or more focused vents may take days to months, and depends on fluid dynamic processes, such as thermally-driven viscous fingering, in the sub-volcanic plumbing system. However, fluid dynamics in a dyke geometry are poorly understood. We perform scaled analogue experiments to investigate convective magma exchange flow within a dyke-like conduit, and discover flow regimes ranging from chaotic mingling to stable, well-organized exchange, over the parameter space relevant for natural eruptions. Experiments are scaled via the Grashof number Gr, which is a Reynolds number for buoyancy-driven exchange flows. We propose that chaotic exchange at high Gr hinders thermally-driven localization by suppressing viscous fingering, whereas flow organization at low Gr enhances localization. Consequently, progressive decrease in Gr through increasing magma viscosity or decreasing dyke width pushes a fissure eruption towards a tipping point that results in rapid localization. Our findings indicate that current conceptual models for magma flow in a dyke require revision to account for this convective tipping point, and provide a quantitative framework for understanding the evolution of fissure eruptions. © 2020 The Author(s)
关键词	eruption longevity excess degassing exchange flow Hawaiian eruptions magma convection
英文关键词	Geology; Mathematical models; Buoyancy-driven exchange flows; Conceptual model; Hazard management; Parameter spaces; Plumbing Systems; Quantitative frameworks; Thermally driven; Viscous fingering; Reynolds number; atmospheric convection; degassing; fissure; lava flow; magma assimilation; volcanic eruption; Hawaii [United States]; United States
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/203156
作者单位	Department of Earth, Ocean and Ecological Sciences, University of Liverpool, Liverpool, L69 3GP, United Kingdom; Department of Earth Sciences, Durham University, South Road, Durham, DH1 3LE, United Kingdom
推荐引用方式 GB/T 7714	Jones T.J.,Llewellin E.W.. Convective tipping point initiates localization of basaltic fissure eruptions[J],2021,553.
APA	Jones T.J.,&Llewellin E.W..(2021).Convective tipping point initiates localization of basaltic fissure eruptions.Earth and Planetary Science Letters,553.
MLA	Jones T.J.,et al."Convective tipping point initiates localization of basaltic fissure eruptions".Earth and Planetary Science Letters 553(2021).