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史蒂索维特 (Stishovite) 在白-第三纪的边界,老鼠,新墨西哥州
概括
斯蒂索维特是一种密集的二氧化阶段,表明了陆地冲击. 研究人员使用-29MAS NMR和X射线衍射证实其存在于白-第三纪边界样本中,将其与火山石英区分开来.
科学领域:
- 地质地质地质地质地质地
- 矿物学是一门学科.
- 地质化学 地质化学
背景情况:
- 斯蒂索维特是一种高压二氧化多态,是陆地撞击事件的关键指标.
- 虽然在撞击现场发现,但在火山地点没有发现stishovite.
- 了解stishovite的发生有助于区分影响与火山地质记录.
研究的目的:
- 在白纪-第三纪边界层的样本中调查stishovite的存在和性质.
- 确认斯蒂索维特作为新墨西哥州拉顿撞击现场撞击事件的标记.
- 使用先进的分析技术来描述stishovite.
主要方法:
- 固态-29神奇角度旋转核磁共振 (Si-29 MAS NMR) 光谱.
- 进行X射线衍射 (XRD) 分析.
- 样品的热处理以确定stishovite的稳定性.
主要成果:
- Si-29 MAS NMR 揭示了在 -191.3 ppm 的特征共振,表明八面体,证实了晶体的斯蒂索维特.
- 这种共振在加热到850°C时消失了,与stishovite已知的相变相一致.
- 对酸残留物的XRD分析显示了许多峰值,包括八个stishovite的特征,以及石英和等常见矿物.
结论:
- 斯蒂索维特存在于新墨西哥州拉顿的白纪-第三纪边界层内的晶体矿物颗粒中.
- 这些发现支持了stishovite作为陆地撞击事件可靠指标的作用.
- NMR和XRD的组合为stishovite识别提供了强有力的证据.
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