地震の遠隔誘発から推論された海洋アステノスフィアの粘度
Pollitz1, Burgmann, Romanowicz
1F. F. Pollitz and R. Burgmann, Department of Geology, University of California, Davis, Davis, CA 95616, USA. B. Romanowicz, University of California Seismological Laboratory, 475 McCone Hall, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|June 5, 1998
まとめ
1952年から1965年の間,太平洋プレート境界に沿った大規模な地震は,地球規模での地震活動に影響を与えました. 地震後ストレスの変化は,プラーク内地震を引き起こし,世界中で地震のパターンを変化させた.
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
- プレート・テクトニクス (プレート・テクトニクス)
背景:
- 1952年から1965年にかけて,アレウチアン・アークとキュリル・カムチャッカ・トレンチに沿って一連の大規模なインタープレート地震が発生しました.
- これらの出来事は,北太平洋プレート境界の重要な部分に蓄積されたストレスを放出しました.
研究 の 目的:
- この大きな地震のシーケンスに続く地震後のストレス進化を調査するために.
- これらのストレス変化が後の地震活動に及ぼす影響を決定する.
主な方法:
- 張力変化をシミュレートするために,粘弾性カップリングモデルを使用しました.
- モデルにアステノスフィアの粘度5×1017パスカル秒を組み込みました.
- 速度の異常に関する宇宙ベースの地質測定を分析した.
主要な成果:
- 計算された地震後のストレス進化は,観測された地震パターンと一致しています.
- このモデルは,海洋内プレート内地震の誘発を説明している.
- それはまた,遠隔のプレート境界での一時的な地震性のパターンを説明します.
- 異常な速度は,7000×7000kmの領域で,連続後30年間観測されました.
結論:
- 1952年から1965年の地震の連続は,太平洋プレート全体のストレス分布に大きく影響した.
- 地震後のストレス緩和は,次回の地震を誘発し,地球規模の地震性に影響を与えることに決定的な役割を果たしました.
- この発見は,テクトニックプレート境界の相互接続性を強調しています.
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