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ウランシリーズの地化学からマントルの羽根の動力学への洞察
Bernard Bourdon1, Neil M Ribe, Andreas Stracke
1Laboratoire de Géochimie et Cosmochimie, Institut de Physique du Globe de Paris-CNRS, 4 Place Jussieu, 75252 Paris cedex 05, France. bourdon@erdw.ethz.ch
Nature
|December 8, 2006
まとめ
地球の石化圏の下にある議論の余地のある上昇点であるマントルの羽根は,ホットスポットラバのウランシリーズデータによって確認されています. この研究は浮力流をマントルの温度と結びつけ,マントルの羽根の存在を証明している.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地質化学 地質化学
- 火山学 火山学とは
背景:
- ホットスポット火山の源泉として提案されているマントルの羽根の存在は,地球科学における長年の議論である.
- マントルの羽根を理解することは,地球のマントルの熱的,ダイナミック,および組成の進化を理解するために不可欠です.
研究 の 目的:
- ホットスポット・ラバの地化学的トレーサーを用いてマントルの羽根の存在と特性を調査する.
- ホットスポットの浮力流とそれに関連するマントルの温度との間の直接的な関係を確立するために.
主な方法:
- 様々なホットスポットからの火山の溶岩のウランシリーズ不均衡の分析.
- 地化学データと浮力フクロスの地球物理学的測定の相関.
主要な成果:
- ウランシリーズ不均衡のデータは,ホットスポットの下にある熱い浮遊する上流 (マントルプルーム) の直接的な証拠を提供します.
- 弱いホットスポット (例えば,アイスランド,アゾール諸島) は,より強いホットスポット (例えば,ハワイ) に比べてマントルの余分な温度が低い.
- ホットスポットの浮力流とマントルの過剰温度との間には直接的な相関が認められた.
結論:
- この研究は,ホットスポット火山の背後にある原動力としてマントルの羽根の存在を確認した.
- この発見は,羽根の浮気力と熱異常との関係を明らかにし,マントルの動力学に関する理解を深める.
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