2010年8月8日のチリ地震による地平面の変化
Marcelo Farías1, Gabriel Vargas, Andrés Tassara
1Departamento de Geología, Universidad de Chile, Plaza Ercilla 803, Santiago, Chile. mfarias@dgf.uchile.cl
Science (New York, N.Y.)
|July 31, 2010
まとめ
2010年のチリ地震 (Mw 8.8) は,500kmの海岸線に沿って陸地レベルの大きな変化を引き起こしました. 昇降はヒンドルラインの西に発生し,沈降は東に発生しました.
科学分野:
- ジオデシ (Geodesy) とは
- 地震学 地震学とは
- テクトニクス (地質学) とは
背景:
- 2010年のチリ地震 (Mw 8.8) は,重要な地質的影響を及ぼした主要な地震事件でした.
- 沿岸と河川の標識は,地震によって引き起こされる陸地レベルの変化の重要な証拠を提供します.
研究 の 目的:
- 2010年のチリ地震後の地平面の垂直の変化を記録し,分析する.
- コセイズミック移動の範囲とパターンを決定する.
- 地震の断裂とエネルギー放出をモデル化するために.
主な方法:
- 垂直に移動した沿岸および河川の標識のフィールド観察.
- 約500kmのセグメントにおける陸地レベルの変化の分析.
- シンプルな弾性変位モデルの適用.
主要な成果:
- 標識の垂直の移転が観察され,2.5メートルから1メートルまで変化した.
- コセイズミック断裂の最大長さとして500kmのセグメントを特定しました.
- 溝から120km離れた紐線に位置し,上昇した (西) と沈下した (東) 地域を分離しています.
結論:
- 観測された地平面の変化は,単純な弾性変位モデルと一致しています.
- モデルのパラメータは,1835年の地震以来,有意な弾性ストレスの蓄積と放出を示唆しています.
- 2010年のイベントは,貯蔵されたプレート収束エネルギーのほとんどを放出した可能性が高い.
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