海に突入する火山の噴火によって生じる 急速で破壊的な密度流
Michael A Clare1, Isobel A Yeo1, Sally Watson2
1National Oceanography Centre, Southampton, UK.
まとめ
噴火が海に直接流出すると 時速122kmを超える海底の流れが生じます 他の自然災害より速く,これらの強力な海底の流れは,大きな被害を引き起こすことができます.
科学分野:
- 海洋地質学と火山学
- 海洋学と自然災害
背景:
- 陸上の火山噴火は 津波を引き起こすような 熱流を生み出します
- 海に直接流入した火山の物質の行動と影響は 文書化されていないままです
- 以前の研究では 海底の火山噴火によって 生成される海底の流れは 調べられませんでした
研究 の 目的:
- 海洋に直接流入した火山による海底流の特徴を記録し分析する.
- これらの火山の密度流の速度と影響を 他の地質学的な出来事と比較する.
- 大規模な海底火山の噴火の 広範な発生の証拠を提供するためです
主な方法:
- 火山噴火後の海底データ分析
- 火山の密度流の流速と流出距離の測定
- 水中に潜った火山の周りの地質学的な特徴と掘削されたスローの比較.
主要な成果:
- 火山の物質が急に沈んだ斜面に移動すると,海底の流れが非常に速く (122 km/h) 発生しました.
- これらの流れは,地震,洪水,嵐によって引き起こされるものよりも長い距離 (> 100 km) を表していました.
- 海底のケーブルを断ち切って 深い穴を掘り起こしました
結論:
- 海底に直接噴火した火山は 強力な破壊的な海底密度流を生み出します
- これらの火山流は 重要なインフラストラクチャである 通信ケーブルを 破壊する危険性があります
- 観測されたスローは,世界中の他の潜った火山の場所で同様の大規模な火山のイベントの証拠を提供します.
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