非火山地震の進化とカリフォルニア州サンシメオンとパークフィールドの地震
Robert M Nadeau1, Aurélie Guilhem
1Berkeley Seismological Laboratory, University of California, Berkeley, CA 94720, USA.
まとめ
閉じられた断層の近くの非火山地震は,地震に先行する可能性があります. 2つの大きな地震の後,サンアンドレアス断層の震動活動は長年にわたって上昇し続け,累積したストレスを示しています.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地震学 地震学とは
- 地震科学は,地震に関する科学である.
背景:
- 非火山地震は,ロックされた断層の近くで発生する地震信号です.
- これらの振動は,地震発生プロセスと関連していると考えられています.
- 震動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:
- 大規模な地震と非火山の震動活動との関係を調査する.
- サンアンドレアス断層の地震発生後の震動パターンの変化を分析する.
- 震動行動から推論されたストレス蓄積率を評価するために.
主な方法:
- パークフィールド地域にあるサンアンドレアス断層の継続的な地震監視.
- 2つの強い地震の前と後の震動の速度と周期性の分析.
- 静的切断とクーロン圧力の変化の計算.
主要な成果:
- 2回の強烈な地震により,地震活動が大幅に増加した.
- 震動活動は高まり,周期的になり,4年以上にわたって続いた.
- 静的切断とクーロン圧力の増加は,突然の震動率の増加と相関しています.
結論:
- 震動の持続的な変化は,サンアンドレアス断層の調査された部分の下の加速したストレス蓄積を示しています.
- この地域は,フォート・テジョンの1857年の地震に似た将来の大きな地震のためにストレスを蓄積しているかもしれません.
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