在185亿年前的萨德伯里撞击结构中的富勒
L Becker1, J L Bada, R E Winans
1Scripps Institution of Oceanography, University of California at San Diego, La Jolla 92093-0212B, USA.
Science (New York, N.Y.)
|July 29, 1994
概括
在萨德伯里撞击结构中发现了富勒伦 (C60和C70). 硫防止了它们在185亿年内氧化,这表明撞击器的外星起源.
科学领域:
- 地质化学 地质化学
- 天体化学是天体化学.
- 撞击坑研究 撞击坑研究
背景情况:
- 富勒 (C60和C70) 是一种具有潜在的外星起源的碳基.
- 萨德伯里撞击结构提供了一个主要的外星撞击事件的独特地质记录.
- 了解撞击突破中的富勒烯保存对于天体生物学和地球化学至关重要.
研究的目的:
- 为了识别和描述萨德伯里冲击结构的冲击产生的裂内的富勒.
- 在冲击环境中,研究富勒在地质时间尺度上的保存机制.
- 根据它们在撞击中发生的情况,探索富勒的潜在地外起源.
主要方法:
- 激光消耗质谱仪 (LDMS) 用于烯检测.
- 激光吸附电离后质谱仪 (LDPI-MS) 提高了灵敏度和特征.
- 高分辨率电子冲击质谱 (HR-EI-MS) 用于精确的质量测定和同位素分析.
- 破裂基质和相关矿物阶段的地球化学分析.
主要成果:
- 富勒伦 (C60和C70) 在萨德伯里撞击结构的Onaping形成突破中被明确地确定.
- 发现C60的度处于百万分之一的范围内.
- 有证据表明,富勒是在撞击羽毛中从玻利德的碳中合成的.
- 作为硫化物-酸盐复合体存在的硫,似乎在185亿年前抑制了富勒烯氧化.
结论:
- 这一发现证实了地面撞击结构中富勒的存在,支持它们在超高速撞击期间的形成.
- 富勒的保存归因于硫化物-酸盐复合体内的封装,保护它们免受氧化.
- 这些发现对了解撞击事件中的碳循环以及在地球和其他行星上保存外星有机分子的潜力有重大影响.
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