铁甲地的哈夫尼同位素层结构
1Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109, USA. Institut fur Isotopengeologie und Mineralische Rohstoffe, Department fur Erdwissenschaften, ETH-Zentrum, NO C61, Sonneggstrasse 5, CH-8092 Zurich, Switzerland.
概括
太平洋中部深水的哈夫同位素显示出显著的欧 - 奥利古波动,可能来自海洋的向. 在过去的2000万年里,哈夫的同位素成分保持一致,这表明太平洋的隔离程度增加了.
科学领域:
- 地质化学 地质化学
- 海洋学 海洋学 海洋学
- 古海洋学是古海洋学.
背景情况:
- 铁甲皮提供了过去海洋化学的宝贵档案.
- 了解纪海洋循环和同位素组成对于古气候重建至关重要.
研究的目的:
- 重建太平洋中部深水中 hafnium (Hf) 的同位素组成的中生纪历史.
- 为了研究海洋循环变化对深海Hf同位素记录的影响.
主要方法:
- 从两个地理上相隔的铁石地的Hf同位素组成的分析,跨越Cenozoic.
- 将Hf同位素数据与已知的海洋和地质事件进行比较.
主要成果:
- 铁甲皮揭示了Hf同位素的类似的世俗变化,尽管它们相距超过3000公里.
- 显著的Hf同位素波动发生在纪和奥利古纪,可能与印度洋和大西洋的向导有关.
- 在过去的2000万年里,Hf的同位素组成相对保持不变,这表明太平洋中部地区的隔离程度有所增加.
结论:
- 太平洋中部深水的Hf同位素成分因过去的海洋学变化而有显著的变化.
- 在过去的2000万年中,Hf同位素的长期均性表明,太平洋中部更加孤立.
- 驱动海水中 (Sr) 同位素变化的机制在代期间没有显著影响太平洋中部深水Hf同位素.
相关概念视频
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