地震と地動力学的データから推論された深層マントルの高粘度流と熱化学構造
1Department of Earth Sciences, University of Western Ontario, Biology & Geology Building, London, Ontario, N6A 5B7 Canada. aforte@uwo.ca
Nature
|April 27, 2001
まとめ
地質学的データは,2000キロメートルの深さ近くの地球マントルの高粘度層を明らかにしています. この層はマントルの流れに影響を及ぼし,深い混合を抑制し,活発なメガプルームをサポートします.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地球科学 地球科学 地球科学
- マントラダイナミクス マントラダイナミクス
背景:
- 表面地質学的データは,マントルのレオロジーと密度についての洞察を提供します.
- 熱コンベクションは,マントルダイナミクスを支配する重要なプロセスである.
研究 の 目的:
- 地物理学データを用いて地球のマントルのレオ学的性質を調査する.
- マントルの流れと,深層マントルの構造とダイナミクスへの影響をモデル化するために.
主な方法:
- 熱コンベクションに関連する地表地球物理学的データの分析.
- 粘性流動モデルの開発と応用.
- 高解像度の地震モデルと鉱物物理データの統合.
主要な成果:
- 2,000kmの深さ近くの高効果粘度領域の推論.
- マントルフローの短距離から長距離の水平スケールへの再編成が観察されました.
- 深層マントルの流れによる変形とコンベクティブ混合の抑制.
- 地震速度の異常と一致する組成と熱の異質性の予測.
結論:
- 深いマントルは,流動パターンに影響を与える高粘度層を示しています.
- 太平洋とアフリカの下のメガプラムは浮気力があり,活発に上流している構造です.
- 地質学的データによって制約されるマントルのコンベクションモデルは,地球深層のプロセスについての理解を向上させます.
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