主要なエオセンのカルシート補償シフトの間,極端な双極氷河は発生しなかった
Kirsty M Edgar1, Paul A Wilson, Philip F Sexton
1National Oceanography Centre, School of Ocean and Earth Science, European Way, Southampton, SO14 3ZH, UK.
Nature
|August 24, 2007
まとめ
大規模な氷床は4160万年前には北半球には存在しなかった. 海洋沈殿物の記録は,南極の氷床が,この期間の氷河化の主要な源であったことを示しています.
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
- 海洋地質学 海洋地質学
背景:
- エオセーン/オリゴセーン境界 (約. 3400万年前) は,南極の恒常的な氷床の形成と海洋カルシット補償深度 (CCD) の深まりを示した.
- 以前の見解では,北半球の氷河期は,はるかに遅れて (1100万~500万年前) 始まったと示唆されていた.
- 最近のエオセンのラフティングと世界の氷の量推定を含む証拠は,このタイムラインに異議を唱え,北半球の氷河化がより早く起こったことを示唆しています.
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