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Updated: Jul 8, 2026

09:41
Blast Quantification Using Hopkinson Pressure Bars
Published on: July 5, 2016
大量の一時的な切断ストレスによって引き起こされる非火山性震動.
Justin L Rubinstein1, John E Vidale, Joan Gomberg
1Department of Earth and Space Science, University of Washington, Box 351310, Seattle, Washington, 98195, USA. justin@ess.washington.edu
Nature
|August 3, 2007
まとめ
サブダクションゾーン付近の非火山性震動は,遠い地震からの地震波によって引き起こされる可能性があります. これは,振動とスロースリップの出来事が,プレートインターフェースの急速な切断ストレスの増加によって引き起こされることを示唆しています.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地震学 地震学とは
- テキトノフィジックスの物理学です.
背景:
- 非衝動的地震放射線,または震動は,火山や潜水地帯で観察されます.
- 非火山による震動の正確な原因は不明であり,流体移動とプレートインターフェースの滑落が主要な仮説である.
- 日本での以前の研究では,震動が低周波地震と,潜水界面のスイヤースリップと関連付けられていた.
研究 の 目的:
- カスカディア・サブデュークション・ゾーンにおける非火山地震の原因を調査する.
- 外部からの地震が震えを誘発するかどうかを判断する.
- 震動,スロースリップイベント,プレートインターフェースのストレスの関係を理解するために.
主な方法:
- カスカディア・サブデュークションゾーンからの地震振動データの分析.
- 2002年のデナリ・アラスカ地震による地震波の到来と地震爆発の相関.
- プレートインターフェースのシアストレスの計算は,ラブ波の位移に基づいて行われます.
主要な成果:
- カスカディアではデナリ地震のラブ波によって引き起こされた地震が確認された.
- 特定のラブ波の移動中に震動が発生し,トリガーメカニズムを示しています.
- 計算された切断張力は約40kPaであり,プレートインターフェースの有効張力が非常に低いことを示唆しています.
結論:
- 震動および潜在的に遅いスリップの出来事は,潜水界面のシャーストレスの増加によって即座に誘発される可能性があります.
- この現象は,増加した運転ストレスに対する摩擦障害反応を表しています.
- この発見は,既存のモデルに異議を唱え,外部のストレスに対する潜水地帯の感受性を強調しています.
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