シンクロトロンの赤外線吸収度測定は,MgSiO3ペロブスキート中の水素を測定した
まとめ
この研究では,マイクロ赤外線スペクトルスコピーを用いて,MgSiO ((3)) ペロブスキットの微量水素を定量化しています. この発見は,地球の下層マントルに水素が有意に存在することを示唆しており,水球と比べると相当する.
科学分野:
- 地質化学 地質化学
- ミネラル物理学 ミネラル物理学
- スペクトロスコーピーは,スペクトロスコーピーを用います.
背景:
- MgSiO(3) ペロブスキットは,地球の下層マントルの主要な鉱物です.
- その微量元素の含有量,特に水素を理解することは,マントルの組成と動力学にとって極めて重要です.
- 名目無水鉱物は,かなりの量の水素を含んでいる可能性があります.
研究 の 目的:
- MgSiO(3) の単結晶の微量水素含有量を測定する.
- このマントルの鉱物の中で水素の分布と濃度を調査する.
- 地下マントルの推定水素含有量と地球の水球を比較する.
主な方法:
- シンクロトロン赤外線源によるマイクロ赤外線スペクトロスコーピーを利用しました.
- ヒドロキシル存在を特定するために,3483cmと3423cmの吸収ピークを分析しました.
- 顕微鏡データに基づく量化水素濃度.
主要な成果:
- MgSiO ((3)) のペロブスキートで2つの異なるプレオクロイヒドロキシル吸収ピークを特定しました.
- 微量水素含有量は,Si原子106個につき700 +/- 170個の原子で,Si原子106個につき700 +/- 170個の原子で決定されました.
- 下層マントルに統合されたこの濃度は,地球の水球質量の約12%であることを計算しました.
結論:
- MgSiO(3) ペロブスキットは,測定可能な,かなりの量の微量水素を含んでいます.
- 下層マントルは水素の大量の貯蔵庫を保持し,マントルの性質に影響を与える可能性があります.
- これらの発見は,地球内の水分と循環の再評価を必要とします.
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