ワシントン州セントヘレンズ山,1980年 火山噴火:最初の16日間のマグマガス成分
まとめ
セントヘレンス山は二酸化硫黄の排出量が低く,マグマガスもほとんどなく,小さな噴火成分を示している. 将来の暴力的な活動の可能性のために,継続的な地球化学的モニタリングが推奨されます.
科学分野:
- 地質化学 地質化学
- 火山学 火山学とは
背景:
- ワシントン州セントヘレンズ山は,1980年の大きな噴火で知られている活発な層火山です.
- 進行中の噴火の地化学的特性を理解することは,危険性評価に不可欠です.
研究 の 目的:
- マグマガス成分と,セントヘレンズ山からの最近の噴火の羽根と関連した潜在的な健康上の危険を評価する.
- 火山活動の継続的なモニタリング戦略を参考にするために.
主な方法:
- 噴火羽根からの二酸化硫黄 (SO2) 排出量の分析.
- 火山灰の溶液分析により,硫黄 (S) と塩素 (Cl) の比率を決定する.
- 灰の断片を顕微鏡で検査し,非状性について調べる.
主要な成果:
- 低レベルの二酸化硫黄の排出が検出されました.
- 火山灰の浸出物には,硫黄と塩素の比率が低いことが示されました.
- 灰の断片は主に非状であり,限られたマグマガス相互作用を示唆しています.
結論:
- 地化学的なデータは,最近の活動に小さな噴火性マグマ成分があることを示しています.
- 灰の溶解性フッ素濃度が低いため,健康に直接的なリスクはありません.
- 現在の排出量が低いにもかかわらず,激しいマグマ活動の可能性は,継続的な地球化学的モニタリングを必要とします.
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