コメント on "アルカインとパレオプロテロゾーイク時代の海洋リドックス状態における鉄同位体制約"
Kosei E Yamaguchi1, Hiroshi Ohmoto
1Institute for Research on Earth Evolution (IFREE), Japan, Agency for Marine-Earth Science and Technology (JAMSTEC),2-15 Natsushima, Yokosuka 237-0061, Japan. kosei@jamstec.go.jp
Science (New York, N.Y.)
|January 18, 2006
まとめ
堆積硫化物中の鉄同位体は,古代の大気中の酸化を正確に反映していない可能性があります. これらの鉱物の起源を誤って解釈することは,地球に関する以前の結論に異議を唱える.
科学分野:
- 地質化学 地質化学
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 同位体地質学とは,同位体地質学のことです.
背景:
- 以前の研究では,堆積硫化物中の鉄同位素が,23億年から18億年前の大気中の酸化変化を示唆していた.
- この解釈は,硫化物形成が大気条件を直接追跡するという仮定に基づいています.
研究 の 目的:
- 堆積硫化物における鉄同位体組成物の解釈を再評価する.
- これらのミネラルの代替的起源を調査し,大気中の酸化から切り離すことができる.
主な方法:
- 鉱物の起源と形成経路の分析.
- 同位体データと地質学的文脈の比較.
主要な成果:
- この研究は,堆積硫化物の起源に関する誤った解釈を明らかにした.
- これらの鉱物の形成の代替メカニズムが提案されています.
- これらの代替的な起源は,鉄の同位体記録が,大気中の酸化のみを反映していないことを示唆しています.
結論:
- Rouxel et al.が導き出した結論 大気中の酸化に関する知識は,鉱物の起源の誤った解釈によって損なわれています.
- 堆積硫化物と古代の大気条件の関係を解明するためにさらなる研究が必要である.
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