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Updated: Jul 7, 2026

04:21
Small Volume (1-3L) Filtration of Coastal Seawater Samples
Published on: June 19, 2009
マントルの流れ場は,北米西部の下にある
1Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015, USA. silver@dtm.ciw.edu
まとめ
北米西部の下のマントルの流れは,プレート運動に反対して東に移動します. この弱い結合は,おそらく古代のファラロンプレートからの深層マントルの密度の変動が,流れを駆動することを示唆しています.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- テキトノフィジックスの物理学です.
- 地震学 地震学とは
背景:
- 構造板の表面運動はよく理解されています.
- しかし,対応する水平マントルの流れは,ほとんど未定のままである.
- マントルの流れを理解することは,プレート構造学にとって極めて重要です.
研究 の 目的:
- 北米西部の下のマントルの水平流域を推定する.
- マントルフローとテクトニックプレート運動の間の結合を調査するために.
主な方法:
- 表面変形観測と上層マントルの地震アニソトロピーのデータを組み合わせた.
- 速度計算のためにホットスポット基準フレームを使用した.
主要な成果:
- 推定マントルの速度は,年間5.5 +/- 1.5cmの東向きである.
- 観測されたマントルの流れは,北米のプレート運動 (西南西) にほぼ反対です.
- マントルの流れは,表面プレートとの弱い結合を示し,その結果,最小の牽引力が生じます.
結論:
- 推定されたマントルの流域は,マントルの密度の異質性によって影響を受ける可能性が高い.
- これらの異質性は,古代のファラロン海板の残骸に由来する可能性がある.
- この発見は,地表構造に影響を与える地球深層のプロセスについての洞察を提供します.
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