リトスフィア-アステノスフィアの境界にある水性溶融の羽根源
Daniel Blatter1,2, Samer Naif3, Kerry Key4
1Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA. dblatter@ucsd.edu.
Nature
|April 21, 2022
まとめ
構造板の下にある 柔軟なアステノスフィアの起源は議論されている. 我々の研究によると マントルの羽根が 揮発性物質に富んだ溶液を入れ替えて プレート構造に必要な 低粘度チャネルを作り出しました
科学分野:
- 地理学
- 構造学
- マントルダイナミクス
背景:
- プレート構造は,石層-石層境界 (LAB) 以下の低粘度アステノスフィアに依存しています.
- この柔らかい層の起源は議論されており,温度,水分化,または部分溶解などの原因が提案されています.
- 以前の研究では,融解の安定性と抵抗性の不確実性が同時に考慮されていなかった.
研究 の 目的:
- LABの低粘度チャネルの起源を調査する.
- LABチャネル内の溶解分数と揮発性成分を制限する.
- マントルの羽根活動への影響を決定する.
主な方法:
- 実験的に制限されたマントルの融解のパラメータ化と,揮発性の存在を組み合わせた.
- ココスプレートからの磁電流データにベイズ反転を適用した.
- 溶融の熱力学的安定性と抵抗力の推定を統合した.
主要な成果:
- 導電性LABチャネルには,大きな溶融分数または大きな揮発性成分が必要です.
- 大量の溶けた分子は機械的に不安定で 移動モデルと矛盾しています
- 発見は,マントルの羽根が LAB チャンネルに 揮発性物質に富んだ溶液を埋め込んだことを示唆している.
結論:
- LABチャネルの特徴は,マントルの羽根源を指しています.
- ガラパゴスのホットスポットからの影響か
- LAB異常の広範囲にわたる源となる可能性があります.
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