プレカンブリア時代の岩石における有機物質の炭素同位体研究
Science (New York, N.Y.)
|March 17, 1972
まとめ
地球上の初期の生命は,大きな進化のイベントを経験したかもしれない. 古代南アフリカの岩石の分析は,明確な炭素シグネチャを明らかにし,初期の生物学的プロセスと光合成の重要な変化を示唆しています.
科学分野:
- 地質化学 地質化学
- パレオバイオロジーの古生物学
- 初期の地球の条件.
背景:
- 南アフリカの初期のプレカンブリア時代の桜は,古代の生地化学的サイクルについての洞察を提供します.
- これらの構造における炭素の同位体の組成を理解することは,初期の生命を再構築するために極めて重要です.
研究 の 目的:
- 初期プレカンブリアの桜における還元炭素の同位体組成を調査する.
- 炭素シグネチャーに反映された潜在的な進化的出来事を特定するために.
主な方法:
- チャートサンプルにおける還元炭素の同位体分析 (デルタ13C PDB).
- 古代の炭素シグネチャーと既知の光合成有機物質の比較.
主要な成果:
- 上の/中部のオンヴェルワッチとフィグツリー群の減少炭素は,若い光合成物質と同様の値 (ミリ当たり-28.7) を示しています.
- Lower Onverwacht cherts (Theespruit formation) は,異常に重い炭素 (-16.5 per mil) を表している.
結論:
- 炭素同位体値の有意な不連続は,初期の生物進化の主要なイベントを示唆しています.
- この出来事は,地球初期の光合成経路や微生物生態系を潜在的に変えた.
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