セントヘレンス山の下の深い地震:マグマガス輸送の証拠?
まとめ
1982年の噴火の40日前のセントヘレンズ山の下の深い地震は,より大きな火山系が活発であったことを示しています. これは,深い貯水池からのマグマティックガスの放出が爆発的な出来事を助長したことを示唆しています.
科学分野:
- 火山学 火山学とは
- 地震学 地震学とは
- 地質物理学 地質物理学とは地質物理学です.
背景:
- セントヘレンス山は,1982年3月20日の噴火の前に噴火前の地震活動を経験しました.
- 以前の地震は,一般的に浅いもので,3km未満の深さで発生していました.
研究 の 目的:
- 1982年のセントヘレンズ山噴火に先立つ噴火前の地震の深さと特徴を分析する.
- 深い地震が火山系の活動と噴火の動態に及ぼす影響を理解する.
主な方法:
- 1982年3月20日の噴火前に記録された地震データの分析.
- 地震の深さの比較と以前のドーム形成噴火の深さの比較.
主要な成果:
- 小規模な地震は,1982年の噴火の40日前に始まった.
- これらの地震の有意な部分は,深さ5~11キロメートルで発生した.
- これらのイベントの深さは,以前の噴火と比較して,火山系の大きな影響を受けた容量を示唆しています.
結論:
- 深い地震活動は,1982年の噴火の前に,より広範な火山系の関与を示しています.
- 地震のタイミングと深さは,深い貯水池から上へと移動するマグマガスと一致し,噴火を引き起こしています.
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