ネバダ州デビルズホールの50万年の安定した炭素同位体記録です
まとめ
デビルズホールのカルシートの炭素13の変異は,過去の気候変化を明らかにします. これらの炭素同位体記録は,氷河の終結と相関しており,大気中の二酸化炭素と植物の密度の変化を示唆しています.
科学分野:
- 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,古代気候学 (paleoclimatology) とは
- 地質化学 地質化学
- イソトープ水文学のイソトープ
背景:
- デビルズ・ホール・カルシット・コア (DH-11) は,過去の環境条件の貴重なアーカイブを提供します.
- 過去の気候変動の変動を理解することは,将来の気候変動を予測するために不可欠です.
研究 の 目的:
- DH-11カルシットコアにおける炭素-13 (デルタ(13) C) 変化を分析する.
- 核におけるデルタ (13C) と酸素同位体比の関係を調査する.
- 観測されたデルタ13C変動の古老環境への影響を解釈する.
主な方法:
- DH-11コアからの静脈カルシットにおける炭素-13 (デルタ(13) C) の分析.
- デルタ (((13) Cのタイムシリーズと酸素同位体データとの比較.
- デルタ13C変動の潜在的な源をモデリングする.
主要な成果:
- 4つの顕著なデルタ13C最小値は,氷河の終結点VからIIの近くで特定されました.
- デルタ (((13) Cのタイムシリーズは酸素同位体記録と逆相関しており,最大7000年先行しています.
- これらの変動は,水層補給水のデルタ (C) の変化を反映している可能性が高い.
結論:
- デルタの13C記録は,世界の大気中のCO2の変化や,大盆地の南部における地域的な植生の変化を示唆する可能性がある.
- デルタの最小値は,植物の最大範囲と密度の時期に対応しています.
- これらの同位体信号をデビルズ・ホールまで,大きな変化なしに運ぶメカニズムは,まだ未解決の問題である.
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