カリフォルニア州北ヘイワード断層に沿って地震の可能性
1Department of Earth and Planetary Science and Berkeley Seismological Laboratory, 307 McCone Hall, University of California, Berkeley, Berkeley, CA 94720, USA. Mail Stop 300-233, Jet Propulsion Laboratory, California Institute of Technology.
まとめ
ヘイワード断層は,表面と深層のクリープ速度が年間約7mmで測定され,有意なアセイミッククリープを示しています. このクリープは滑り率と調和しており,北部の断層部分で大きな独立地震の可能性が低いことを示唆しています.
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:
- ヘイワード断層は,大きな地震の断裂と無地震のクリープの両方を表しています.
- クリープの行動を理解することは,地震の危険性評価に不可欠です.
研究 の 目的:
- 北部のヘイワード断層に沿った無地震のクリープ速度を定量化するために.
- 観測されたクリープと長期の滑り率と地震の可能性を調和させるため.
主な方法:
- GPSとInSARからの表面変形データの分析.
- 脱位をモデル化して,断層滑り,断層滑り,断層滑り,断層滑り,断層滑り,断層滑り,断層滑りを推論する.
- 繰り返されるマイクロ地震の特定と分析.
主要な成果:
- 20kmの北部のセグメントに沿って,表面のクリープ率は約7mm/年です.
- 深い水深 (4〜10km深) のクリープ率は,年間5〜7mmである.
- 機械モデルでは,電流のクリープと,年間10mmの長期滑り率を調和させています.
結論:
- 北部のヘイワード断層は,有意なアセイミック・クリープを示している.
- 閉じられた南部のセグメントに隣接するこのクリープは,北部のセグメントで大きな独立した地震の可能性を減らす可能性があります.
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