断層滑り率は,繰り返されるマイクロ地震の再発間隔から深さで発生する
1Earth Sciences Division, Lawrence Berkeley National Laboratory, and Berkeley Seismological Laboratory, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|July 31, 1999
まとめ
研究者らは,カリフォルニア州パークフィールドの微小地震パターンを分析して,深さでの断層滑り率を推定した. この新しい方法は,地震活動に関連した滑り率の変化を明らかにし,断層地帯を監視する新しい方法を提供します.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地震学 地震学とは
- 地震科学 地震科学 地震科学
背景:
- 繰り返されるマイクロ地震のシーケンスには,ユニークな属性があります.
- 地震リスクの評価には,深さでの滑り率を理解することが重要です.
研究 の 目的:
- マイクロ地震の時間間隔を用いて深層滑り率を推論する方法を開発し,適用する.
- 活発な断層に沿った滑り率の空間的および時間的変動を調査する.
主な方法:
- カリフォルニア州パークフィールドの11年間のマイクロ地震性記録の分析.
- 似たような,繰り返されるマイクロ地震のシーケンス間の時間間隔を利用する.
- 推論された滑り率と地震活動,および独立の滑り量との相関.
主要な成果:
- スリップ率のシステマティックな空間的および時間的変化が特定されました.
- 観測された滑り速度の変動は,地震活動と同期していた.
- この方法は,他の断層ゾーンの滑り測定と一致していることが示されました.
結論:
- マイクロ地震のシーケンスを使用して,深い断層の滑り率を推測することができます.
- この現象は,地震発生的な断層地帯のストレインフィールドを監視するための潜在的な方法を提供します.
- 他の活性欠陥に対する一般的な適用性を確認するために,さらなる研究が必要である.
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