マントルの源の関数として,海中の玄武岩におけるレドックス異質性は,マントルの源の関数である
Elizabeth Cottrell1, Katherine A Kelley
1National Museum of Natural History, Smithsonian Institution, Washington, DC 20560, USA. cottrelle@si.edu
まとめ
地球 地球 地球 地球 地球 地球
科学分野:
- 地質化学 地質化学
- ペトロロジー・ペトロロジーとは
- 地球科学 地球科学 地球科学
背景:
- 地球上の上層マントルの酸化状態は,マントルの進化に影響を与え,記録しています.
- 上層マントルの酸化状態の系統的な微細スケールの変動は,以前は,海中の玄武岩で認識されていませんでした.
研究 の 目的:
- 上層マントルの酸化状態の体系的な変動を調査する.
- マントルの酸化状態とマントルの源組成の関係を理解する.
主な方法:
- 中洋ののベースルトガラスのグローバル調査.
- Fe (((3+) /ΣFe比の分析について.
- マントルの濃縮指数 (例えば87Sr/86Sr,208Pb/204Pb,Ba/La,Nb/Zr) との相関分析を行った.
主要な成果:
- マントルの酸化状態は,マントルの源組成によって体系的に変化します.
- 濃縮されたマントルは,Fe ((3+) /ΣFeと濃縮指数の間の負の相関によって示される,枯渇したマントルよりも減少しています.
- 炭素は,濃縮されたおよび濃縮されたマグマを生成する要因として提案されています.
結論:
- マントルの酸化状態は,マントルの源の組成と関連しています.
- 炭素は,海中のマグマの減少と濃縮に役割を果たしています.
- この研究は,上層マントルの酸化状態の微細な変化を明らかにしています.
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