まとめ
岩石の張りの変化が磁気特性を変化させ,地震を予測する可能性がある. マグネトメーター配列は,サンアンドレアス断層のクリープに先立つ地磁場シフトを検知し,ピエゾ磁気信号が断層の活動を予測できることを示しています.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地球科学 地球科学 地球科学
- 地震学 地震学とは
背景:
- 岩はピエゾマグネティックな性質を示し,つまりストレス変化が磁気感受性や残留磁化に影響する.
- これらの磁気変化は,地元の地磁場に影響を及ぼし,地下ストレスをモニタリングするための潜在的な方法を提供します.
研究 の 目的:
- 活性断層ストレスに関連したピエゾ磁気信号を調査する.
- 地磁場の変化が断層活動に先行するかどうかを判断する.
主な方法:
- マグネトメーターの微分配列は1965年から稼働しています.
- 配列はサンアンドレアス断層に位置し,活発なストレス条件下でピエゾ磁気効果を検出します.
主要な成果:
- 地元の地磁場の変化は,カリフォルニア州ホリスター近くで観測されました.
- これらの磁場変動は,サンアンドレアス断層の突然のクリープ移転イベントの数十時間前に発生しました.
結論:
- 観測された地磁場の変化は,ピエゾ磁気信号の検出を示唆しています.
- ピアズマグネティックモニタリングは,アクティブ・フォールト・ストレスを予測し,その後のクリープ・イベントを予測する手段を提供することができる.
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