概括
这项研究挑战了在特里亚斯纪-罗纪边界期间大气中二氧化碳恒定的想法. 层级图形问题和甲污染可能会影响以前关于二氧化碳水平的发现.
科学领域:
- 古气候学 古气候学
- 地质化学 地质化学
- 在平流图学上,平流图学是平流图学.
背景情况:
- 三叠纪 - 罗纪的边界标志着一个重要的环境变化时期.
- 坦纳等人之前的研究. 建议在这个边界上保持稳定的大气二氧化碳水平.
- 古碳酸盐碳同位素组合经常用于重建过去的大气CO2.
研究的目的:
- 质疑在三叠纪 - 罗纪边界期间大气中二氧化碳水平恒定的说法.
- 要突出用于支持索赔的方法的局限性.
主要方法:
- 对地平线图完整性的批判性分析.
- 在古碳酸盐样本中评估潜在的甲污染.
- 评估甲氧化对碳同位素代理物的影响.
主要成果:
- Stratigraphic 的不完整性可能会影响地质记录的可靠性.
- 大气中的甲 (CH4) 具有轻的同位素组成.
- 甲氧化为二氧化碳可以干扰基于碳同位素的古巴测量.
结论:
- 在罗纪-罗纪的边界上,大气中二氧化碳的恒定性是可疑的.
- 使用当前的碳同位素古巴计,可能无法检测甲-酸盐解离和氧化事件.
- 需要进一步的研究来完善重建过去大气二氧化碳水平的方法.
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