海洋无氧事件1a的放射性同位素时间表:驱动机制分析框架
Youjuan Li1, Brad S Singer1, Reishi Takashima2
1Department of Geoscience, University of Wisconsin-Madison, Madison, WI 53706, USA.
Science advances
|November 20, 2024
概括
澄清了海洋无氧事件1a (OAE1a) 的时间和原因. 通爪高原的火山活动很可能触发了OAE1a,这是来自日本的同位素转移和化石数据所证明的.
科学领域:
- 地质科学是地球科学.
- 古气候学 古气候学
- 同位素地球化学 同位素地球化学
背景情况:
- 海洋无氧事件1a (OAE1a) 代表了全球碳循环中期的重大扰动.
- 正确的时间,速度和驱动OAE1a的潜在机制仍然是科学调查的主题.
研究的目的:
- 准确地确定OAE1a.的发病时间和持续时间.
- 通过分析碳和同位素外流来研究OAE1a的致病机制.
- 为了将OAE1a与诸如通爪高原火山活动等重大地质事件相关联.
主要方法:
- 使用U-Pb石分析对布进行放射测年.
- 在泥石中对碳和的稳定同位素分析.
- 使用索引化石 (例如,Leupoldina cabri) 的生物层级分析.
主要成果:
- OAE1a的发病时间为119.55万年前,持续时间约为1116 kyr.
- 标志着OAE1a迅速发作的和碳同位素外游,每次持续约115 kyr.
- 化石 *Leupoldina cabri* 追溯到通爪高原基岩之后,这表明了一个时间联系.
结论:
- 通爪高原的火山活动被确定为非放射性和轻碳的可能来源.
- 与通爪高原相关的火山活动是OAE1a的可能致病机制.
- 这项研究完善了时间表,并提出了这一主要碳循环事件的关键驱动因素.
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