まとめ
1971年のサン・フェルナンド地震の近くの地表の高さの変化は,ストレスを緩和する断層岩のモデルと一致しています. これは,地震発生前に断層滑り率が著しく増加したことを示唆している.
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:
- 1971年のサンフェルナンド地震は,地形が大きく変形した.
- 地震前の断層の振る舞いを理解することは,地震の危険性評価に不可欠です.
研究 の 目的:
- 1971年のサンフェルナンド地震以前の断層地帯の岩石の機械的振る舞いを調査するために.
- 観測された地面標高の変化と理論的な地震モデルとの一致性を評価する.
主な方法:
- 1971年の地震前と後の地表の高さの変化を測定するジオデシックのデータの分析.
- 観測された変形を,断層岩の理論的なストレンス軟化モデルからの予測と比較.
主要な成果:
- 観測された地面標高の変化は,理論的なモデルと一致しています.
- このモデルは,断層地帯の岩石がピークストレスを達成した後,ストレスの緩和を経験したことを示しています.
- 焦点付近の暗示的な地震前の断層滑り率は,年間約0.1メートルに達しました.
結論:
- 1971年のサンフェルナンド地震の変形は,ストレスを緩和する断層岩モデルによって説明されています.
- 断層滑り率の増加が地震に先行し,提案されたモデルと一致しています.
- この研究は,地震の力学と前駆的現象の理解を深める.
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