一个有弹性氧化的上层海洋的晚期开始
Wanyi Lu1, Andy Ridgwell2,3, Ellen Thomas4,5
1Department of Earth Sciences, Syracuse University, Syracuse, NY, USA.
概括
大约2亿年前,海洋氧气水平大幅上升,改善了海洋生物的条件. 这项研究使用与的比率来追踪地球可居住性中的这些关键变化.
科学领域:
- 地质化学 地质化学
- 古海洋学是古海洋学.
- 地球系统科学 地球系统科学
背景情况:
- 海洋和大气氧气的上升对地球的可居住性至关重要.
- 在上层海洋中,追踪超越溶解氧气附近的甲动物生存值是具有挑战性的.
研究的目的:
- 用与的比率重建上层海洋氧化的世俗变化.
- 调查主要海洋氧化事件的时间和驱动因素.
主要方法:
- 从海洋碳酸盐中编制广泛的与 (I/Ca) 比率.
- 分析地质记录以推断过去的大气氧气水平.
- 利用地球系统模型来模拟海洋学变化.
主要成果:
- 大约4亿年前大气氧部分压力显著上升的证据.
- 在上层海洋氧化到近现代条件的明显阶段性变化发生在大约2亿年前.
- 200万年前的-信号与更深层的有机物重矿化有关.
结论:
- 这项研究揭示了地球氧化历史的关键里程碑.
- 增加的真核浮游生物尺寸和生物矿物化可能是200万年前海洋氧化事件的驱动因素.
- 这些发现增强了我们对在地质时间尺度上控制海洋可居住性的因素的理解.
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