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Updated: Jul 12, 2026

06:04
Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
トングステンのイソトープは,マントルの羽根が地球の核からの貢献を含まないという証拠です
Anders Scherstén1, Tim Elliott, Chris Hawkesworth
1Department of Earth Sciences, University of Bristol, Will's Memorial Building, Queen's Road, Bristol BS8 1RJ, UK. anders.schersten@bristol.ac.uk
Nature
|January 16, 2004
まとめ
海洋島ベサルトのボルンゲンイソトープは,コア・マントルの混合モデルをサポートしていません. これは,コア相互作用ではなく,リサイクルされた海洋地殻が,これらの玄武岩のオスミウム同位体異常を説明することを示唆しています.
科学分野:
- 地質化学 地質化学
- イソトープ地球化学 イソトープ地球化学
- ペトロロジー・ペトロロジーとは
背景:
- 海洋島玄武岩 (OIBs) のオスミウム同位体比は,2つのモデルによって説明されます:リサイクルされた海洋地殻または地球の外部のコア相互作用.
- トングステン (W) は siderophile元素で,マントルで枯渇し,コア貢献に敏感です.
研究 の 目的:
- トングステンイソトープを用いてOIB源におけるコア・マントル混合とリサイクルされた地殻の役割を調査する.
- ハワイと南アフリカの岩石のボルンガム同位体データを分析することによって,コア貢献モデルをテストする.
主な方法:
- ハワイと南アフリカの岩石サンプルを高精度のボルンガム同位体分析.
- トングステンの同位体データを既存のオスミウム同位体データと地化学モデルと比較.
主要な成果:
- 分析されたサンプルでは,負のボルンガム同位体値は観察されなかった.
- 予測された負のボルンガムイソトープ値の欠如は,コアマントルの混合モデルと矛盾しています.
結論:
- OIBにおけるオスミウム同位体異常の説明として,単純なコアマントルの混合シナリオは排除されています.
- リサイクルされた海洋殻は,OIBsの源のより妥当な構成要素であり,観測されたオスミウム同位体濃縮を説明します.
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