地球のマントルの酸化状態を設定する 深いマグマの海洋形成
Katherine Armstrong1, Daniel J Frost2, Catherine A McCammon1
1Bayerisches Geoinstitut, University of Bayreuth, D-95447 Bayreuth, Germany.
まとめ
地球の初期の大気は,金属鉄が核に分離するにつれて,より酸化した. この過程は二酸化炭素が ダイヤモンドとして沈殿することを可能にすることで 惑星の炭素豊富な内部も説明します
科学分野:
- 地化学
- 惑星科学
- 高圧鉱物物理学
背景:
- 地球の大気組成はマントルの酸化還元状態と関連している.
- マントルの酸化は,核形成が始まってから増加した.
- 初期の地球の化学的進化を理解することは 大気の起源の鍵です
研究 の 目的:
- 地球のマントルのリドックス進化とその大気組成への影響を調査する.
- 高圧下にある深層マグマの海で 鉄の振る舞いを決定する
- 地球の酸化した大気と 炭素に富んだ内部の起源を説明するために
主な方法:
- 高圧実験で深海マグマをシミュレートする
- 極端な圧力下での鉄 (Fe2+) の不均衡を分析する.
- マグマの海から金属鉄の分離を調査している.
主要な成果:
- 鉄 (Fe2+) は高圧下では非比例的に鉄 (Fe3+) と金属鉄に変化する.
- コアへの金属鉄の分離は,マントルの酸化状態を増加させた.
- 脱ガスした揮発性物質は より酸化した大気種を形成した.
- マグマの海洋における酸化還元グラデーションは CO2 の降水をダイヤモンドとして促進した.
結論:
- 蓄積過程におけるマントルのリドックス進化は,地上の大気組成に大きな影響を与えた.
- 金属鉄の核への分離は,大気中の酸化における重要な要因である.
- マグマの海洋リドックス・グラディエントは 大気中の酸化と ダイアモンドとしての深層の炭素結合の両方を説明します
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