マグマ室ダイナミクスにおける揮発性物質の役割
Herbert E Huppert1, Andrew W Woods
1Institute of Theoretical Geophysics, Department of Applied Mathematics and Theoretical Physics, Silver Street, Cambridge CB3 9EW, UK. heh1@esc.cam.ac.uk
Nature
|December 6, 2002
まとめ
アンデシット火山は,より長い期間,より多くのマグマを噴出することができます. 新しいモデルは,マグマ中のガス圧縮性が,蓄積されたエネルギーを放出することによって,噴火の容量と期間を大幅に増加させることができることを示しています.
科学分野:
- 火山学 火山学とは
- 地質物理学 地質物理学とは地質物理学です.
- 地質化学 地質化学
背景:
- アンデシトの火山は頻繁に噴火し,長期間にわたって大量のマグマを放出します.
- 観測された噴火速度のサイクルは,マグマの再充填と貯水器の圧力によって影響を受け,数時間から数年の範囲に及ぶ.
研究 の 目的:
- マグマのガス圧縮性の噴火動態への影響をモデル化するために.
- 噴火の期間と量を増加させる可能性のあるメカニズムを調査する.
主な方法:
- マグマ内のガス圧縮性の効果を組み込む数値モデルの開発.
- 蓄積された内部エネルギー放出が噴火パラメータにどのように影響するかを分析する.
主要な成果:
- このモデルは,噴火の期間と量の100倍もの増加を予測しています.
- この効果は,溶けた揮発性物質から蓄積されたエネルギーの放出によって増幅されます.
- 浅いマグマ室や,揮発性物質に富んだマグマは,このエネルギー放出メカニズムを好む.
結論:
- ガス圧縮性は,火山噴火を調節し,潜在的に増幅する重要な要因です.
- カントリー・ロックによるマグマの冷却はエネルギー放出を強化し,より大きな噴火につながる可能性があります.
- この発見は,アンデシト火山の長期的な行動に関する新しい洞察を提供します.
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