开放德雷克海峡的时间和气候影响
Howie D Scher1, Ellen E Martin
1Department of Geological Sciences, University of Florida, Gainesville, FL 32611, USA. howie@earth.rochester.edu
概括
大约4100万年前,德雷克海峡开放,使太平洋水进入南大洋. 这一事件影响了海洋循环,生产力和全球冷却,建立了一个关键的南极通道.
科学领域:
- 古代海洋学 古代海洋学 古代海洋学
- 气候科学 气候科学
- 地质地质地质地质地质地
背景情况:
- 关于德雷克海峡开通的时间有争议,影响了对海洋循环和全球冷却的理解.
- 同位素数据提供了对过去海洋学条件的洞察.
研究的目的:
- 确定德雷克海峡开通的时间及其对海洋循环的影响.
- 研究海洋学变化与全球气候变化之间的关系.
主要方法:
- 在阿古拉斯山脊的新同位素比率的世俗变化的分析.
- 海洋门户的地质约会.
主要成果:
- 证据表明,大约4100万年前,太平洋海水涌入南大洋.
- 德雷克海峡的开放和深化与生物生产率的增加和气候波动相吻合.
- 德雷克通道的开放时间早于塔斯马尼亚大门,表明早期的环南极流.
结论:
- 德雷克海峡的开通极大地影响了南大洋的循环和全球气候.
- 海洋循环和生物生产率的变化与大气二氧化碳的下降有关.
- 一个完整的环南极路径由Eocene晚期建立.
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