Mechanism and rate of magma degassing : Toward an understanding of bifurcation of explosive-effusive silicic volcanism

岩浆脱气的机制和速率：了解爆炸性喷流硅质火山的分叉

• 批准号: 21684025
• 负责人: OKUMURA Satoshi
• 金额: $ 14.39万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (A)
• 财政年份: 2009
• 资助国家: 日本
• 起止时间: 2009 至 2011
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21684025/
• 关键词: 火山現象; 火山噴火; マグマ; 脱ガス; 爆発的噴火; 変形実験; X線ラジオグラフィー

A factor controlling the style and explosivity of volcanic eruptions is magma degassing during its ascent in a volcanic conduit. To understand the mechanism of the degasing and determine the degassing rate, we experimentally simulated magma ascent and observed in situ the deformation of magma by using originally developed deformation apparatus which was built up on synchrotron radiation X-ray imaging system in SPring-8. The experimental results demonstrated that the degassing rate from flowing magma was high. This result implies that some unknown mechanisms inhibit the degassing for explosive volcanism.

控制火山喷发样式和爆发力的一个因素是岩浆在火山导管上升过程中的脱气。为了解脱气机理，确定脱气速率，利用春-8同步辐射x射线成像系统上自行研制的变形仪，对岩浆上升过程进行了模拟实验，并对岩浆变形进行了现场观测。实验结果表明，流动岩浆的脱气速率较高。这一结果表明，一些未知的机制抑制了爆发火山作用的脱气。

项目成果

Experimental constraints on permeable gas transport in crystalline silicic magmas

结晶硅岩浆中可渗透气体输运的实验约束

• DOI: 10.1007/s00410-012-0750-8
• 发表时间: 2012
• 期刊: Contributions to Mineralogy and Petrology Springer
• 作者: Okumura S.;Nakamura M.;et al
• 通讯作者: et al

The H2O content of andesitic magmas from three volcanoes in Japan, inferred from the infrared analysis of clinopyroxene

• DOI: 10.1127/0935-1221/2011/0023-2141
• 发表时间: 2011-10
• 期刊: European Journal of Mineralogy
• 影响因子: 2.1
• 作者: S. Okumura

珪長質マグマからの開放系脱ガス

长英质岩浆的开放系统脱气

• 发表时间: 2010
• 作者: M.Menard;R.Ishii;T.Higo;E.Nishibori;H.Sawa;S.Nakatsuji;J.Chan;奥村聡・中村美千彦・土山明・中野司・竹内晋吾・上杉健太朗
• 通讯作者: 奥村聡・中村美千彦・土山明・中野司・竹内晋吾・上杉健太朗

Evolution of microstructure of bubbles and gas permeability in sheared rhyolite

剪切流纹岩中气泡微观结构和气体渗透率的演化

• 发表时间: 2010
• 作者: Okumura;S.;M.Nakamura;T.Fujioka;A.Tsuchiyama;S.Takeuchi;T.Nakano;K.Uesugi
• 通讯作者: K.Uesugi

間隙圧オシレーション法を用いた高温高圧下でのマグマの浸透率測定

孔隙压力振荡法测量高温高压岩浆渗透率

• 发表时间: 2011
• 作者: 宇尾竜一;他;奥村聡・岡崎啓史・片山郁夫
• 通讯作者: 奥村聡・岡崎啓史・片山郁夫