气候变化领域集成服务门户(CCPortal): Modeling Magma System Evolution During 2006–2007 Volcanic Unrest of Atka Volcanic Center, Alaska

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DOI	10.1029/2020JB020158
	Modeling Magma System Evolution During 2006–2007 Volcanic Unrest of Atka Volcanic Center, Alaska
	Zhan Y.; Gregg P.M.; Lu Z.
发表日期	2021
ISSN	21699313
卷号	126 期号:2
英文摘要	Surface deformation and seismicity provide critical information to understand the dynamics of volcanic unrest. During 2006–2007, >80 mm/yr uplift was observed by interferometric synthetic aperture radar (InSAR) at the central Atka volcanic center, Alaska, coinciding with an increasing seismicity rate. On November 25, 2006, a phreatic eruption occurred at the Korovin volcanic vent, 5-km north of the central Atka, following the drainage of its crater lake a month prior to the eruption. The InSAR data are assimilated into three-dimensional finite element models using the Ensemble Kalman Filter to investigate: (1) the pressure source creating the surface deformation; (2) the triggering of the volcano-tectonic (VT) earthquakes in the Atka volcanic center; and (3) the triggering of the phreatic eruption at Korovin. The models show that the pressure source required to create the surface deformation is a NE-tilted, oblate ellipsoid, which rotated from steep to gentle dipping from June to November 2006 before the eruption. The modeled dilatancy in a pre-existing weak zone, coinciding with the Amlia-Amukta fault, driven by the pressure source has a spatial and temporal correlation with the evolution of the VT earthquakes during the unrest. The fault dilatancy may have increased the connected porosity and permeability of the fault zone allowing fluid injection which triggered the observed seismicity. In addition, the dilatated fault may have increased the fluid capacity of the fault zone by ∼105 m3, causing the discharge of the crater lake at Korovin. Consequently, the phreatic eruption of the Korovin volcano may have been triggered. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	failure; numerical modeling; permeability; seismicity; stress; volcanic unrest
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187333
作者单位	Department of Geology, University of Illinois – Urbana-Champaign, Urbana, IL, United States; Now at: Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC, United States; Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX, United States
推荐引用方式 GB/T 7714	Zhan Y.,Gregg P.M.,Lu Z.. Modeling Magma System Evolution During 2006–2007 Volcanic Unrest of Atka Volcanic Center, Alaska[J],2021,126(2).
APA	Zhan Y.,Gregg P.M.,&Lu Z..(2021).Modeling Magma System Evolution During 2006–2007 Volcanic Unrest of Atka Volcanic Center, Alaska.Journal of Geophysical Research: Solid Earth,126(2).
MLA	Zhan Y.,et al."Modeling Magma System Evolution During 2006–2007 Volcanic Unrest of Atka Volcanic Center, Alaska".Journal of Geophysical Research: Solid Earth 126.2(2021).