概括
苏格兰奥尔多维纪-西卢里纪边界页岩中高度与灭绝事件没有相关性. 地球上的超级岩石侵蚀,而不是外星撞击,很可能解释了这些持续的水平.
科学领域:
- 地质化学 地质化学
- 古生物学的古生物学
- 在平流体学上,平流体学是平流体学.
背景情况:
- 奥尔多维克-西卢尔纪的边界标志着一个重要的灭绝事件.
- 异常常常与外星撞击有关.
- 苏格兰的多布斯林 (Dob's Linn) 是奥尔多维纪-西卢里纪边界的一个关键层型区域.
研究的目的:
- 为了调查在多布斯林的奥尔多维纪-西卢里纪边界的度.
- 为了确定石灰岩页岩部分高度的来源.
- 评估含量与重大灭绝事件之间的关系.
主要方法:
- 从Dob's Linn部分采集的页岩样本进行化学石图分析.
- 测量和的度.
- 源区域的古地理和地质重建.
主要成果:
- 在整个检查的边界区间和周围的13个石墨矿石区域中发现了持续高度 (0.0500.250ppb).
- 尽管发生了重大灭绝事件,但在边界或其他地方没有检测到的度峰值.
- 的度与相对应,呈现逐渐下降到低纪,与的比率平均为106.6.
结论:
- 高度和持续的度归因于暴露的上层地幔超岩的陆地侵蚀.
- 这些发现并不支持灾难性的外星事件作为高水平的原因.
- 该研究强调了陆地过程在沉积物序列内的地化学异常中的重要性.
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