大型小行星碰撞后,石被快速运送到地球
Philipp R Heck1, Birger Schmitz, Heinrich Baur
1ETH Zürich, Isotope Geology, NO C61, CH-8092 Zürich, Switzerland.
Nature
|July 16, 2004
概括
大型小行星撞击可以迅速将石送到地球. 这项研究证实小行星碎片的转移时间短,约为10^5年,验证了轨道模拟.
科学领域:
- 行星科学 行星科学
- 宇宙化学 宇宙化学
- 地质地质地质地质地质地
背景情况:
- 小行星带的碰撞可以增加地球上的石撞击率.
- 轨道动态表明碎片可能比目前观察到的更快地到达地球.
- 来自小行星撞击的高效石传递机制需要经验验证.
研究的目的:
- 为了调查石从小行星碰撞到地球的转移时间.
- 为通过轨道模拟预测的快速石传递提供经验证据.
- 在古代化石石中分析宇宙射线产生的贵重气体.
主要方法:
- 高灵敏度的高贵气体测量在染色体颗粒.
- 从大约4.8亿年前的沉积物中分析化石石.
- 转移时间与地平面高度的相关性.
主要成果:
- 推导出的石转移时间最短为大约10^5年.
- 转移时间随着地层学高度的增加而增加,与沉积持续时间一致.
- 来自一颗被摧毁的小行星的长期流星雨的证据.
结论:
- 证实小行星碰撞可以创建高效的石运送轨道到地球.
- 证明小行星带中的强共振可以在短时间内将物质运送到太阳系内部.
- 提供了强有力的证据,证明大撞击事件后小行星碎片的快速输送.
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