气候变化领域集成服务门户(CCPortal): Explosivity of basaltic lava fountains is controlled by magma rheology, ascent rate and outgassing

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DOI	10.1016/j.epsl.2020.116658
	Explosivity of basaltic lava fountains is controlled by magma rheology, ascent rate and outgassing
	La Spina G.; Arzilli F.; Llewellin E.W.; Burton M.R.; Clarke A.B.; de' Michieli Vitturi M.; Polacci M.; Hartley M.E.; Di Genova D.; Mader H.M.
发表日期	2021
ISSN	0012821X
卷号	553
英文摘要	The dichotomy between explosive volcanic eruptions, which produce pyroclasts, and effusive eruptions, which produce lava, is defined by the presence or absence of fragmentation during magma ascent. For lava fountains the distinction is unclear, since the liquid phase in the rising magma may remain continuous to the vent, fragment in the fountain, then re-weld on deposition to feed rheomorphic lava flows. Here we use a numerical model to constrain the controls on basaltic eruption style, using Kilauea and Etna as case studies. Based on our results, we propose that lava fountaining is a distinct style, separate from effusive and explosive eruption styles, that is produced when magma ascends rapidly and fragments above the vent, rather than within the conduit. Sensitivity analyses of Kilauea and Etna case studies show that high lava fountains (>50 m high) occur when the Reynolds number of the bubbly magma is greater than ∼0.1, the bulk viscosity is less than 106Pas, and the gas is well-coupled to the melt. Explosive eruptions (Plinian and sub-Plinian) are predicted over a wide region of parameter space for higher viscosity basalts, typical of Etna, but over a much narrower region of parameter space for lower viscosity basalts, typical of Kilauea. Numerical results show also that the magma that feeds high lava fountains ascends more rapidly than the magma that feeds explosive eruptions, owing to its lower viscosity. For the Kilauea case study, waning ascent velocity is predicted to produce a progressive evolution from high to weak fountaining, to ultimate effusion; whereas for the Etna case study, small changes in parameter values lead to transitions to and from explosive activity, suggesting that eruption transitions may occur with little warning. © 2020 The Authors
关键词	basalt effusive eruption explosive eruption fragmentation lava fountain magma ascent
英文关键词	Basalt; Explosives; Reynolds number; Sensitivity analysis; Viscosity; Volcanoes; Basaltic eruptions; Effusive eruptions; Explosive activity; Explosive eruption; Lower viscosities; Numerical results; Parameter spaces; Volcanic eruptions; Fountains; basalt; fragmentation; lava flow; magma chamber; numerical model; plinian eruption; rheology; sensitivity analysis; viscosity; Catania [Sicily]; Etna; Hawaii [(ISL) Hawaiian Islands]; Hawaii [United States]; Hawaiian Islands; Italy; Kilauea; Sicily
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/203173
作者单位	Department of Earth and Environmental Sciences, The University of Manchester, Manchester, United Kingdom; Department of Earth Sciences, Durham University, Durham, United Kingdom; School of Earth and Space Exploration, Arizona State University, Tempe, United States; Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Pisa, Pisa, Italy; Bayerisches Geoinstitut, Universität Bayreuth, Bayreuth, Germany; School of Earth Sciences, University of Bristol, Bristol, United Kingdom
推荐引用方式 GB/T 7714	La Spina G.,Arzilli F.,Llewellin E.W.,et al. Explosivity of basaltic lava fountains is controlled by magma rheology, ascent rate and outgassing[J],2021,553.
APA	La Spina G..,Arzilli F..,Llewellin E.W..,Burton M.R..,Clarke A.B..,...&Mader H.M..(2021).Explosivity of basaltic lava fountains is controlled by magma rheology, ascent rate and outgassing.Earth and Planetary Science Letters,553.
MLA	La Spina G.,et al."Explosivity of basaltic lava fountains is controlled by magma rheology, ascent rate and outgassing".Earth and Planetary Science Letters 553(2021).