急速な加速は,地震のような実験室での実験の急速な弱まりにつながります
J C Chang1, D A Lockner, Z Reches
1Geology and Geophysics, University of Oklahoma, 100 East Boyd Street, Norman, OK 73019, USA.
Science (New York, N.Y.)
|October 9, 2012
まとめ
この研究は,フライホイールを用いて地震の断層滑行をシミュレートし,地震パラメータがエネルギー放出をどのように推定するかを明らかにします. 破裂時の高加速は,強烈な磨損による断層の弱まりを加速する.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地震科学 地震科学 地震科学
- ロック・メカニクス ロック・メカニクス
背景:
- 地震は破裂フロントとして広がり,滑り落ちて貯蔵された地殻のエネルギーを放出する断層を活性化します.
- 断層パッチの振る舞いを理解することは,地震の危険性評価と地震の予測に不可欠です.
研究 の 目的:
- 地震時の断層パッチの滑り方をシミュレートするために.
- 地震パラメータとエネルギー放出との関係を調査する.
- ダイナミックな弱体化における加速の役割を探求する.
主な方法:
- 試行錯誤パッチスリップの実験シミュレーションは,高速にロードされた実験錯誤を使用します.
- 旋回するフライホイールに蓄えられたエネルギーは,急速な負荷のために使用されました.
- 力,加速,速度の自発的な進化を監視する.
主要な成果:
- 実験結果は,モーメントマグニチュード (M(w)) 4〜8の地震における断層パッチの振る舞いのプロキシとして機能します.
- 移動,速度,大きさ,断裂エネルギーなどの地震パラメータは,地震のエネルギー放出強度を定量化することができます.
- 破裂フロントからの高い加速は,激しい断層ゾーンの磨損を通じて動的弱化を加速します.
結論:
- 実験的なシミュレーションにより,地震の破裂の動態に関する洞察が得られる.
- 地震データを活用して,地震中に放出されたエネルギーを推定することができます.
- ダイナミックな弱化は,加速と摩擦磨損によって大きく影響されます.
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