1992年のLanders (カリフォルニア州) の地震後の地殻下部の粘着弾性流動
1Seismological Laboratory 252-21, California Institute of Technology, Pasadena, CA 91125, USA.
まとめ
1992年のLanders地震後の地震後の変形は,宇宙地質学を用いてモデル化されました. 地殻下部の粘着弾性流は,変形を説明し,地震の危険性や盆地と帯域の構造についての洞察を提供します.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- テクトニクス (地質学) とは
- 地震学 地震学とは
背景:
- 1992年のLanders地震の後,大規模な地震後の変形が観察されました.
- 地震後の変形を理解することは,地震の危険性評価に不可欠です.
研究 の 目的:
- 1992年のLanders地震後の地震後の変形を駆動するメカニズムを調査する.
- 観測された変形に対するアフタースリップと粘着弾性流の貢献をモデル化するために.
主な方法:
- 広範囲の地震後の変形を観察するために,宇宙ジオデシーのデータを利用しました.
- 変形プロセスをシミュレートするために3次元モデルを開発しました.
- 地殻下層の粘度を推定した.
主要な成果:
- アフタースリップだけでは,観測されたすべての水平および垂直の位移を説明することはできません.
- 厚さ約10kmの地殻下層の粘着弾性流は,水平および近垂直の地震後の変形の両方を成功裏に説明しました.
- この弱い層の粘性は,約10^18パスカル秒であると決定されました.
結論:
- 地殻下部の粘着弾性流は,大規模な地震後に発生する地震後の反発の支配的なメカニズムです.
- このメカニズムは,バシン・アンド・レンジ州の拡張構造を説明するかもしれない.
- この発見は,地震の危険性分析の改善に意味を持つ.
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