カムチャッカの下の壊滅的なスラブ喪失の地震的証拠
Vadim Levin1, Nikolai Shapiro, Jeffrey Park
1Department of Geology and Geophysics, Box 208109, Yale University, New Haven, Connecticut 06520, USA. vadim.levin@yale.edu
Nature
|August 16, 2002
まとめ
壊滅的なスラブ喪失イベントは,地震画像によって証明されたカムチャッカ半島を再構成しました. これらの出来事は,太平洋プレートの終結とこの地域の火山の歴史を説明します.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- プレート・テクトニクス (プレート・テクトニクス)
- 火山学 火山学とは
背景:
- アレウト島とカンチャッカの交差点は,太平洋北西部の複雑な地質学的な境界線です.
- 地震構造を理解することは,この地域の地質学的進化を解読する上で極めて重要です.
研究 の 目的:
- アレウチア - カムチャッカ交差点と周辺地域の下の地震構造をイメージする.
- カムチャッカの過去1000万年の構造と火山の歴史を調査する.
主な方法:
- サブリトスフィアの構造の地震画像.
- テクトニックと火山の進化の分析.
主要な成果:
- 沈下する太平洋の石層は,アレウト島とカンチャッカの交差点で終わる.
- 消滅したカンチャッカ北部の火山の弧の下には,遺跡の石版は存在しない.
- カムチャッカ北部の下の上層マントルでは,異常に遅いシェア波速度が観測され,スラブ損失を示唆しています.
結論:
- カムチャッカの近年の地質学的な過去において,少なくとも2つの破滅的なスラブ喪失のエピソードは起こった.
- 弱い分離と損失は,大陸の衝突だけでなく,海洋の収束縁の進化の重要な要因です.
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