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DOI	10.1016/j.epsl.2021.117017
	Discharge rate of explosive volcanic eruption controls runout distance of pyroclastic density currents
	Roche O.; Azzaoui N.; Guillin A.
发表日期	2021
ISSN	0012821X
卷号	568
英文摘要	We address, through quantitative analysis of results from independent studies, the control of the discharge rate of explosive volcanic eruptions on the runout distance of highly hazardous pyroclastic density currents. We analyze with statistical methods data from 47 well-documented currents with runouts of ∼3–185 km and generated by minor eruptions to super-eruptions with discharge rates Q∼107–1012 kg/s. Our analysis shows first that the discharge rate during the phase of pyroclastic density currents is on average 13.6 times greater than the rate during the preceding plinian phase. We further find that the runout of both dilute turbulent currents and of two-layer flows with a concentrated base correlates remarkably well with the discharge rate. By applying the power law relationships we infer, we next model the as yet unknown discharge rates of over 53 events, including 27 super-eruptions. At a given rate, dilute currents travel on land generally farther than their concentrated counterparts, and they are even more mobile when propagating over water. We further demonstrate that the runout of dilute current scales with (Q/w)0.5, with w the particle settling velocity, in agreement with theory. Assuming concentrated PDCs obey the same principle we infer particle settling velocities of ∼1–10 m/s for these currents. We show also that the classical deposit aspect ratio, AR, allows to discriminate between emplacement from dilute (AR<∼5×10−5) and concentrated (AR>∼5×10−5) current, which permits us to discuss the dynamics of PDCs produced by the Ito (29 ka) and Taupo (AD 232) eruptions. © 2021 Elsevier B.V.
关键词	discharge rate explosive volcanism power law relationship pyroclastic density current runout distance super-eruption
英文关键词	Aspect ratio; Explosives; Volcanoes; 'current; Discharge rates; Explosive volcanism; Particle settling velocity; Power-law relationship; Pyroclastic density currents; Run outs; Runout distances; Super-eruption; Volcanic eruptions; Concentration (process); explosive volcanism; power law; pyroclastic deposit; pyroclastic flow; settling velocity; volcanic eruption; Trachinotus falcatus
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/203272
作者单位	Laboratoire Magmas et Volcans, University Clermont Auvergne, CNRS, IRD, OPGC, Clermont-Ferrand, 63000, France; Laboratoire de Mathématiques Blaise Pascal, University Clermont Auvergne, CNRS, Clermont-Ferrand, 63000, France
推荐引用方式 GB/T 7714	Roche O.,Azzaoui N.,Guillin A.. Discharge rate of explosive volcanic eruption controls runout distance of pyroclastic density currents[J],2021,568.
APA	Roche O.,Azzaoui N.,&Guillin A..(2021).Discharge rate of explosive volcanic eruption controls runout distance of pyroclastic density currents.Earth and Planetary Science Letters,568.
MLA	Roche O.,et al."Discharge rate of explosive volcanic eruption controls runout distance of pyroclastic density currents".Earth and Planetary Science Letters 568(2021).