在主要的Eocene石灰岩补偿转移期间没有极端的双极冰川
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
概括
41,600万年前北半球没有大型冰盖. 海洋沉积物记录表明,南极冰盖是这个时期冰河形成的主要来源.
科学领域:
- 古气候学 古气候学
- 海洋地质学海洋地质学
背景情况:
- 埃奥森/奥利古森的边界 (大约. 3400万年前) 标志着永久的南极冰盖的建立和海洋石灰岩补偿深度 (CCD) 的深化.
- 以前的观点表明,北半球的冰川开始的时间要晚得多 (1100万到500万年前).
- 最近的证据,包括以纪冰上漂流和全球冰量估计,挑战了这个时间线,表明北半球早期的冰川化.
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