ストレスの蓄積と放出を直接測定することによって,時間的に予測可能な地震の再発をテストします
1Geophysics Department, Stanford University, Stanford, California 94305-2215, USA. jrmurray@pangea.stanford.edu
Nature
|September 20, 2002
まとめ
危険性評価に用いられる,時間予測可能な地震モデルが,カリフォルニア州パークフィールドで失敗した. これは,単純な地質学的な環境でも,地震の再発を予測する際の限界を示唆しています.
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
- 地震科学 地震科学 地震科学
背景:
- 確率的地震リスク評価は,時間分布モデルを使用しています.
- 弾性反発に基づいた時間予測可能な再発モデルでは,地震の確率は最後の出来事以降の時間とともに増加すると仮定しています.
- このモデルは,カリフォルニア州,ニュージーランド,日本などの地震が頻発する地域で広く適用されています.
研究 の 目的:
- 時間の予測可能な地震再発モデルの正確性を評価するために.
- モデルの適用性をよく文書化され,比較的単純な構造構造の環境でテストする.
主な方法:
- 繰り返しの時間制限を推定するために,地質測定の逆転.
- 1966年のパークフィールド地震とその後の地震サイクルの分析.
主要な成果:
- 時間予測モデルでは,1987年までにパークフィールドセグメントで地震が再発すると予測していた.
- 地測量データの逆転により,モデルの予測が満たされなかったことが明らかになった.
- モデルは,この理想的なテスト場所において,重大な故障を証明した.
結論:
- カリフォルニア州パークフィールドでの予測可能な時間モデルの失敗は,その信頼性に関する懸念を引き起こしています.
- 単純な地形構造の設定におけるモデルの限界は,世界的な複雑な断層システムにおけるその適用を妨げることがあります.
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