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クレタ紀末の大量絶滅期におけるデッカントラップのパルス噴火に関するU-Pbの制約
Blair Schoene1, Michael P Eddy2, Kyle M Samperton3
1Department of Geosciences, Princeton University, Princeton, NJ, USA. bschoene@princeton.edu.
Science (New York, N.Y.)
|February 23, 2019
PubMed で要約を見る
まとめ
大規模な火山噴火は,白紀-旧紀 (K-Pg) 絶滅の前後に発生した. これらの噴火は,チクスルブ衝突とともに,K-Pgの大量絶滅につながる環境変化を引き起こした.
科学分野:
- 地理科学
- 古生物学
- 環境科学
背景:
- 大陸の浸水ベースルト地域は 大量絶滅に繋がっています
- デッカン・トラップの噴火とチクスルブの衝突は,白亜紀・古亜紀 (K-Pg) 絶滅の出来事に関与している.
- 噴火から放出される揮発性物質は環境の悪化を引き起こす可能性があります.
研究 の 目的:
- デッカン・トラップの噴火が K-Pgの大量絶滅を引き起こしたという仮説を検証するために
- デッカン・トラップの噴火パルスを正確に年代付けする.
- 噴火のタイミングとK-Pgの絶滅を相関させるため
主な方法:
- デッカンの噴火率を推定するために,ウラン-鉛 (U-Pb) ジルコンの地球年代測定法が使用されました.
- 年代測定は,4つの異なる高量の噴火期を特定しました.
主要な成果:
- デッカン噴火の最大発生率は,K-Pgの絶滅前と後に発生した.
- 隕石が衝突して絶滅する 数万年前には 噴火パルスが発生した
- 噴火活動がK-Pgの境界を横切った.
結論:
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