まとめ
巨大な小惑星の衝突は大気の変化を引き起こし,酸雨を引き起こし,大陸の気象の変化を増加させた. この地質学的な出来事は,古代の海水で観察された高いストロンチウム同位体比を説明する可能性がある.
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
- インパクトクラテリング (インパクトクラテリング)
背景:
- クレータ紀末期は,地質学的および環境的な大きな変化によって特徴づけられています.
- 海水におけるストロンチウムイソトープ比は,大陸の風化と地殻の過程の記録を提供します.
研究 の 目的:
- 大型ボリデの衝突と地球のシステムにおける地化学的変化の関連を調査する.
- クレータ紀末期の海水における観測された高いストロンチウム-87/ストロンチウム-86の比率を説明するために.
主な方法:
- 大気中の衝撃加熱とそれに続く化学反応をモデル化する.
- 酸性降雨が大陸の気象に及ぼす影響を分析した.
- 衝突による気象変動と海洋ストロンチウムイソトープ記録の相関.
主要な成果:
- ボリド衝突は,大気中の衝撃加熱によって,かなりの窒素酸化物を発生させます.
- 衝突事故に起因する酸性降雨は,大陸の気象化を劇的に増加させる.
- 気候の悪化により,大陸の地殻から大量のストロンチウムが海に放出され,海水の87Sr/86Sr比率が上昇する.
結論:
- 大型ボリドの衝突は,観測された白亜紀後半のストロンチウム同位体外れを誘発した可能性が高い.
- ストロンチウムイソトープ記録の他の時間における同様のピークは,他の衝撃イベントまたは激しい気象のエピソードを示す可能性があります.
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