加ケル山脈の超低速の広がりに関する最近の火山活動の証拠
M H Edwards1, G J Kurras, M Tolstoy
1Hawaii Institute of Geophysics and Planetology, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, 96822, USA. margo@soest.hawaii.edu
Nature
|March 10, 2001
まとめ
超低速に広がるGakkel Ridgeで火山活動が発見され,海中の火山活動に関する以前の仮定に異議を唱えました. この発見は,最もゆっくりと広がる速さでも,集中して大規模な噴火が発生することを示唆しています.
科学分野:
- 地質学 地質学 地質学
- 地質物理学 地質物理学とは地質物理学です.
- 海洋学 海洋学 海洋学
背景:
- 海底が海洋中部の山脊に広がるのは,火山や地質学的なプロセスによって引き起こされる.
- 火山活動の影響は,拡散速度が低下するにつれて減少し,超低速 (<1.5cm yr(-1)) で未知の活動があります.
研究 の 目的:
- 超低速に広がるGakkel Ridgeの火山活動の範囲を調査する.
- 重要な火山活動が年1.5cm以下で発生するかどうかを判断する.
主な方法:
- 核潜水艦の船体に搭載されたソナーを使用して,Gakkel Ridgeの3次元ソナーマップを取得しました.
- 東部のGakkel Ridgeからのサイドスキャンのソナーデータを分析した.
主要な成果:
- 東部のGakkel Ridgeの軸谷にある約720km2の2つの若い火山をマッピングしました.
- 西部の火山がテレシーズミックイベントの震源と一致していることを確認し,最近の軸の噴火を示唆しました.
- この超緩慢に広がる山脊で,集中した,多量の,そして潜在的に頻繁な噴火が観察されました.
結論:
- 大規模な火山活動は,超低速に広がる中海の山脊で起こります.
- ガッケル山脈の噴火は局所的で,以前に考えられていたよりもかなり大きい.
- この研究は,極端な海底の広がり速度での火山の過程についての私たちの理解を再構築します.
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