GPSでモニタリングされたチリ中央の2010 Mw 8.8 Mauleメガトラスト地震
1Laboratoire de Géologie de l'Ecole Normale Supérieure, UMR CNRS 8538, Paris, France. vigny@biotite.ens.fr
Science (New York, N.Y.)
|April 30, 2011
まとめ
2010年のモール地震は,地殻の大きな変形を引き起こし,滑り込みは断層アスペリティに集中し,浅い深さまで広がった. アフトスリップはコセシミックスリップが低い場所で発生し,複雑な破裂ダイナミクスを示しています.
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
- テクトニクス (地質学) とは
背景:
- 大規模な地震は地殻の変形を引き起こし,それは地質学技術で測定できます.
- 断層滑り分布を理解することは,地震リスクの評価に不可欠です.
研究 の 目的:
- GPSデータを用いて,2010年に発生したマウレの8.8MWの巨大地震の静的変形と動力学を推論する.
- マール地震の滑り分布と破裂の特徴を決定するために.
主な方法:
- チリ中央部からのグローバルポジショニングシステム (GPS) ネットワークデータを使用した.
- 断層滑りと変形を推論するために弾性モデリングを適用した.
- 低周波データを用いて地震の中心を移した.
主要な成果:
- 破裂は約500kmに広がり,滑り幅は最大15mで,2つのアスペリテージに集中した.
- 破裂は浅い深さに達し,潜水槽まで広がる可能性がある.
- アフトスリップは低コセイズミックスリップの地域で観察されました; 低震源は40 km SWに移動しました.
結論:
- マウール地震は,浅い滑り,大きなアフタースリップで複雑な破裂行動を示した.
- 破裂は ~3.1 km/sで双方向に広がり,メガトラスト地震のダイナミクスの詳細な理解を示唆しています.
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