纳米钻石在年轻德里亚斯时期的边界沉积物层中的纳米钻石
D J Kennett1, J P Kennett, A West
1Department of Anthropology, University of Oregon, Eugene, OR 97403, USA. dkennett@uoregon.edu
Science (New York, N.Y.)
|January 3, 2009
概括
在北美沉积物中发现的丰富的纳米钻石表明,在年轻德里亚斯开始时发生了宇宙撞击事件. 这一外星事件可能导致了广泛的生态和生物破坏.
科学领域:
- 地质地质地质地质地质地
- 宇宙化学 宇宙化学
- 古气候学 古气候学
背景情况:
- 纳米钻石是碳的异构体,需要极端的条件才能形成.
- 以前的研究已经将纳米钻石与外星撞击事件联系起来.
研究的目的:
- 研究北美沉积物中纳米钻石的存在和起源.
- 为了确定纳米钻石层的时间和地理范围.
主要方法:
- 来自多个北美地区的沉积物核心分析.
- 选择区域电子衍射 (SAED) 用于纳米钻石的表征.
- 纳米钻石的度分析.
主要成果:
- 丰富的纳米钻石在 12.9 ± 0.1 千日历年之前的沉积物中发现.
- 发现了两种钻石类型 (立方体和n-钻石),表明存在高温,高压条件.
- N-钻石度在10-3700ppb之间,与已知的撞击层相比.
结论:
- 纳米钻石提供了强有力的证据,证明了涉及碳状地铁或彗星的宇宙撞击事件.
- 这次撞击很可能发生在年轻德里亚斯冷却间隔开始时.
- 该事件导致多次空气爆发和可能的表面冲击,严重影响北美动植物和人类群体.
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