在过去的2800万年里,一个动态的海洋循环
Elizabeth M Griffith1, Adina Paytan, Ken Caldeira
1Department of Geological and Environmental Sciences, Stanford University, Building 320, Room 118, Stanford, CA 94305, USA. egriffith@ucsc.edu
Science (New York, N.Y.)
|December 17, 2008
概括
海水的同位素比例显示,在过去的2800万年中发生了重大变化. 大约1300万年前的显著变化表明的度正在演变,全球生物地化学系统正在重组.
科学领域:
- 地质化学 地质化学
- 古代海洋学 古代海洋学
- 同位素地球化学 同位素地球化学
背景情况:
- 在过去的2800万年里,海水的同位素组成和度发生了变化.
- 以前的研究表明,海洋同位素比率的变化.
研究的目的:
- 为了重建一个高分辨率,连续的海水同位素比率曲线.
- 识别海水同位素演变中的独特特征,并推断度的变化.
主要方法:
- 分析海洋 (类) 巴里特的高分辨率同位素组成.
- 开发一个连续的海水同位素比率曲线 (delta44/40Ca).
主要成果:
- 形成了一个独特的海水同位素比率曲线,显示出显著的进化特征.
- 在大约1300万年前的低值期后,大约400万年来,delta44/40Ca的0.3每毫升的明显增加发生了.
结论:
- 观察到的海洋同位素比率的变化与重大气候转变和全球碳循环转移有关.
- 这些发现表明,由海水的变化驱动的全球生物地化学系统的重组.
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