概括
稀有,富含碳的石可能引发了大规模灭绝. 在灭绝层中发现的痕迹金属提供了外星撞击事件的证据.
科学领域:
- 地化学,古生物学,行星科学
背景情况:
- 大规模灭绝事件通常与灾难性的地球或外星现象有关.
- 确定过去灭绝的确切触发因素对于了解地球历史和未来风险至关重要.
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