プレート・エッジの海底層の石化層の融解の地化学的証拠
G M Yogodzinski1, J M Lees, T G Churikova
1Department of Geology, Dickinson College, Carlisle, Pennsylvania 17013-2896, USA. yogodzin@dickinson.edu
Nature
|February 24, 2001
まとめ
アダキット (スラブ溶融の成分を持つ火山岩) は,マントルの流れとつながり,引き裂かれた潜水板と相互作用しています. この発見は,潜流ゾーンにおけるマグマの発生に関する理解を洗練している.
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
- テクトニクス (地質学) とは
背景:
- 島弧マグマティズムは通常,海殻を沈殿させ,マントルの融点を下げる流体によって放出される流体によるものです.
- アダキットは,潜水板の溶融を含む火山岩であり,稀であり,通常は若い,暖かい潜水板と関連しています.
- 古い冷たい沈殿板のある地域におけるアダキットの存在は,マグマ発生の現在のモデルに異議を唱える.
研究 の 目的:
- アダキテスの形成機構を調査する.
- アダキテの構造的文脈と地化学的解釈を再評価する.
- アダカイトの誕生におけるマントルフローの役割を調査する.
主な方法:
- カムチャッカ半島とアレウト諸島の火山岩の地化学分析.
- 地化学データの統合とテクトニック設定分析.
- マントルの流れダイナミクスのモデリング 潜水板の縁の周りに.
主要な成果:
- 地化学的なデータは,アダキットのスラブ溶融の起源を再確認する.
- アダカイトの形成は,マントルの流れとつながっており,それは,引き裂かれた潜水板の縁と相互作用しています.
- この発見は,マントルの流れによって,潜水板の縁が加熱または消去されたときにアダキットが形成されることを示唆しています.
結論:
- アダキットは,特定の潜水板幾何学とマントルの流れ相互作用の信頼できる指標です.
- この研究は,マグマの発生と潜流ゾーンの熱構造の理解を洗練します.
- アダキテは,潜水地帯プロセスモデルの改善のためのトレーサーとして使用することができます.
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