撞击喷射物在古世 - 世边界
Morgan F Schaller1, Megan K Fung2, James D Wright3
1Earth and Environmental Sciences, Rensselaer Polytechnic Institute (RPI), Troy, NY 12180, USA. schall@rpi.edu.
概括
一个外星撞击事件发生在5600万年前的古世 - 世热极限期间. 这种影响与地球上显著的气候变化和进化转变有关.
科学领域:
- 地质科学
- 古气候学
- 进化生物学
背景情况:
- 地球外的影响对地球的气候和进化有很大影响.
- 五千六百万年前的古世 - 世热极峰 (P-E) 事件涉及到快速的全球变暖和碳循环中断.
- 这一时期发生了重大的进化变化,包括哺乳动物的扩张和深海灭绝.
研究的目的:
- 为了调查地球外撞击的证据.
- 将撞击事件与P-E热极值期间观察到的气候和进化变化相关联.
主要方法:
- 来自海上P-E边界部分的地质样本的分析.
- 酸玻璃球体的识别和表征
- 战略分析以确定撞击事件的时间.
主要成果:
- 在多个P-E边界段的不同层层中发现了酸盐玻璃球体.
- 这些球体的识别为微铁和微晶.
- 证实外星撞击事件与P-E碳同位素探险相吻合.
结论:
- 一个外星撞击恰好发生在古世-古世的边界.
- 这一撞击事件对了解P-E热极值的气候和进化动态具有重要意义.
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