DOI: 10.1016/j.epsl.2021.117017
论文题名: Discharge rate of explosive volcanic eruption controls runout distance of pyroclastic density currents
作者: Roche O. ; Azzaoui N. ; Guillin A.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2021
卷: 568 语种: 英语
中文关键词: 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
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. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/165650
Appears in Collections: 气候变化与战略
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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
Recommended Citation:
Roche O.,Azzaoui N.,Guillin A.. Discharge rate of explosive volcanic eruption controls runout distance of pyroclastic density currents[J]. Earth and Planetary Science Letters,2021-01-01,568