地球の物質の同位体の性質は,時間とともに増加している
1Origins Laboratory, Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago, Illinois 60637, USA.
Nature
|January 28, 2017
まとめ
地球
科学分野:
- 惑星科学
- 同位体地化学
- 宇宙化学
背景:
- 地球は未知の同位体組成の惑星の胚から形成された.
- 地球と月の同位体相似性は,異質な蓄積のモデルに挑戦しています.
- エンスタチット隕石は 地球と月の同位体相似性を共有しています
研究 の 目的:
- 異なる金属相性を持つ元素を用いて 地球の蓄積物質の同位体の性質を解読する
- 地球と月の同位体相似性を 蓄積モデルと調和させるため
- エンスタタイト隕石の起源と 地球の形成との関係を調査する
主な方法:
- 地球,月,隕石の高精度同位体測定
- リトフィール (O,Ca,Ti,Nd),中等サイドロフィール (Cr,Ni,Mo) と高サイドロフィール (Ru) の元素の分析
- 増殖過程と同位体進化のモデリング.
主要な成果:
- 異なる金属の親和性を持つ元素は,異なる増殖段階を明らかにします.
- すべての分析された元素は,エンスタチット隕石との同位体相似性を示しています.
- 地球の蓄積には,特にその形成の後に,エンスタタイト型の物質の重要な部分が含まれていました.
結論:
- 地球とエンスタタイトの隕石は 同じ同位体貯蔵庫から生まれました
- 月を形成したインパクターには 地球に似た同位体成分があったようです
- 化学的進化は,その後の星雲と惑星の分断プロセスによって分岐した.
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