概括
弗拉斯尼亚-法门尼亚边界附近的一种异常表明,与大规模灭绝有关的石撞击. 然而,化石蓝藻细菌Frutexites可能已经从海水中缩了这些元素,质疑外星起源.
科学领域:
- 地质化学 地质化学
- 古生物学的古生物学
- 沉积物学的沉积物学
背景情况:
- 弗拉斯尼亚-法门尼亚边界标志着一个重要的全球大规模灭绝事件.
- 异常常常与外星撞击有关,例如石撞击.
- 坎宁盆地含有高代纪的岩石,具有这种灭绝事件的潜在证据.
研究的目的:
- 为了调查在坎宁盆地的上代纪岩石中发现的异常.
- 探索这种异常,大规模灭绝事件和流星撞击之间的潜在联系.
- 确定缩元素的来源,调查外星和生物起源.
主要方法:
- 来自坎宁盆地的岩石样本的地化学分析.
- 碳同位素分析以评估生物质变化.
- 用显微镜检查和对化石化蓝藻细菌 (Frutexites) 的元素分析.
主要成果:
- 在Frasnian-Famennian边界的上代纪岩石中检测到一个中度的异常 (20x背景).
- 这种异常与含有化石蓝藻菌Frutexites的斯特罗马托利特床相吻合.
- 和其他元素 (白金,铁,等) 在Frutexites细丝中被发现是2-5倍于矩阵度的度.
结论:
- 虽然异常表明了与大规模灭绝有关的可能的流星撞击,但Frutexites中的元素度提出了另一个假设.
- 果石可能在生物上直接从海水中提取这些元素,从而否定了对外星源的需求.
- 需要进一步的研究,以确定与影响相关的和生物起源之间的区别,观察到的元素度.
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