DOI: 10.1038/ngeo1928
论文题名: Eruption cyclicity at silicic volcanoes potentially caused by magmatic gas waves
作者: Michaut C. ; Ricard Y. ; Bercovici D. ; Sparks R.S.J.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2013
卷: 6, 期: 10 起始页码: 856
结束页码: 860
语种: 英语
Scopus关键词: compaction
; gas flow
; magma
; porosity
; two phase flow
; viscosity
; viscous flow
; volcanic eruption
; volcanic gas
; Central Luzon
; Japan
; Kagoshima [Kyushu]
; Kyushu
; Leeward Islands [Lesser Antilles]
; Luzon
; Montserrat
; Mount Pinatubo
; Philippines
; Sakurajima
; Zambales
; Pinatubo
英文摘要: Eruptions at active silicic volcanoes are often cyclical. For example, at the Soufrière Hills volcano in Montserrat, Mount Pinatubo in the Philippines, and Sakurajima in Japan, episodes of intense activity alternate with repose intervals over periods between several hours and a day. Abrupt changes in eruption rates have been explained with the motion of a plug of magma that alternatively sticks or slides along the wall of the volcanic conduit. However, it is unclear how the static friction that prevents the plug from sliding is periodically overcome. Here we use two-phase flow equations to model a gas-rich, viscous magma ascending through a volcanic conduit. Our analyses indicate that magma compaction yields ascending waves comprised of low- and high-porosity bands. However, magma ascent to lower pressures also causes gas expansion. We find that the competition between magma compaction and gas expansion naturally selects pressurized gas waves with specific periods. At the surface, these waves can induce cyclical eruptive behaviour with periods between 1 and 100 hours, which compares well to the observations from Soufrière Hills, Mount Pinatubo and Sakurajima. We find that the period is insensitive to volcano structure, but increases weakly with magma viscosity. We conclude that observations of a shift to a longer eruption cycle imply an increase in magma viscosity and thereby enhanced volcanic hazard. © 2013 Macmillan Publishers Limited. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/106678
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: Laboratoire de Sciences Spatiales et Planétologie, Université Paris Diderot, Sorbonne Paris Cité, Institut de Physique du globe de Paris, UMR 7154 CNRS, F-75013 Paris, France; Laboratoire de Géologie de Lyon, UMR 5276 CNRS, Université Lyon 1, ENS Lyon, 69622 Villeurbanne, France; Department of Geology and Geophysics, Yale University, New Haven, CT 06520-8109, United States; Department of Earth Sciences, Wills Memorial Building, University of Bristol, Bristol BS8 1RJ, United Kingdom
Recommended Citation:
Michaut C.,Ricard Y.,Bercovici D.,et al. Eruption cyclicity at silicic volcanoes potentially caused by magmatic gas waves[J]. Nature Geoscience,2013-01-01,6(10)