埃迪亚卡拉海洋的分层氧化还原模型
Chao Li1, Gordon D Love, Timothy W Lyons
1Department of Earth Sciences, University of California, Riverside, CA 92521, USA. chaoli@ucr.edu
概括
在埃迪亚卡尔时期,海洋化学具有明显的eocinic和ferruginous区域. 这种分层海洋模型解释了早期动物化石的分布.
科学领域:
- 古海洋学是古海洋学.
- 地质化学 地质化学
- 古生物学的古生物学
- 埃迪亚卡拉时期 埃迪亚卡拉时期
- 早期的动物进化是什么?
背景情况:
- 埃迪亚卡尔时期 (6.35亿到5.42亿年前) 见证了重要的环境变化和第一个宏观动物的出现.
- 了解埃迪卡拉海洋化学对于解释早期生命的进化轨迹至关重要.
- 之前的研究提出了埃迪亚卡拉深海的相互矛盾的地球化学氧化还原条件.
研究的目的:
- 重建埃迪亚卡拉时期详细的空间和时间海洋化学.
- 为了调查南华盆地的环境条件,中国南部,在埃迪亚卡拉.
- 为了调和相互矛盾的地化学数据,并解释早期元生动物的化石记录.
主要方法:
- 分析南华盆地的杜尚图岩层,中国南部.
- 详细的空间和时间重建埃迪卡拉海洋化学.
- 地化学建模以模拟海洋分层和氧化还原条件.
主要成果:
- 发现证据表明大陆架上有eocinic (无毒和硫化) 水的转移稳定区域.
- 发现与架子eoginia共存的含有铁的[Fe (II) ]丰富的深水.
- 一个动态维护的分层海洋,在整个埃迪亚卡拉的同时代有氧,硫化和铁质区域,受低海洋硫酸盐度的青.
结论:
- 这项研究提出了一个分层的埃迪亚卡海洋模型,该模型调和了以前相互冲突的地球化学氧化还原条件.
- 这种海洋化学模型为理解早期元生动物化石的时间分布提供了一个框架.
- 这些发现突出了海洋化学和早期动物进化在埃迪亚卡拉期间的复杂相互作用.
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