在罗纪海洋无氧事件期间,气体酸盐的大规模解离
1Department of Earth Sciences, University of Oxford, UK. stephen.hesselbo@earth.ox.ac.uk
Nature
|August 10, 2000
概括
在早期的托尔克时代,气体水合物释放的甲可能导致了地球水库中广泛传播的轻碳同位素,尽管有机碳埋葬率很高. 这一事件发生在约1.83亿年前.
科学领域:
- 古气候学 古气候学
- 地质化学 地质化学
- 古生物学的古生物学
背景情况:
- 早期托拉克纪的海洋无氧事件 (大约. 18300万年前) 与高有机碳埋葬,高温和大规模灭绝有关.
- 在此期间,以前对轻碳同位素的解释主要集中在局部上游.
- 岩石和化石中的重碳同位素被归因于轻碳的埋葬.
研究的目的:
- 为了调查在早期托尔克纪海洋无氧事件期间轻碳同位素的来源.
- 为了确定局部上升是否可以解释全球碳同位素异常.
- 为观察到的碳同位素模式提出一个替代机制.
主要方法:
- 碳同位素分析的化石木材从早期托尔克时期.
- 化石木材的同位素数据与海洋有机物,岩石和化石的现有数据的比较.
- 建模可能的碳循环扰乱.
主要成果:
- 化石木材显示,同位素轻碳主导着海洋,生物圈和大气储库.
- 这些轻碳标记在全球范围内持续存在,即使有机碳埋葬率很高.
- 这些发现与仅仅基于局部上游的解释相矛盾.
结论:
- 广泛的轻碳同位素标志表明碳循环的全球性扰乱.
- 从海洋气体水合物中大量和快速释放甲被认为是主要的驱动因素.
- 这种甲释放事件类似于晚古世热量最大值的拟议机制.
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