Shocked Quartz in the Cretaceous-Tertiary Boundary Clays: Evidence for a Global Distribution

@article{Bohor1987ShockedQI,
  title={Shocked Quartz in the Cretaceous-Tertiary Boundary Clays: Evidence for a Global Distribution},
  author={Bruce Forbes Bohor and Peter J. Modreski and Eugene E. Foord},
  journal={Science},
  year={1987},
  volume={236},
  pages={705 - 709}
}
Shocked quartz grains displaying planar features were isolated from Cretaceous- Tertiary boundary clays at five sites in Europe, a core from the north-central Pacific Ocean, and a site in New Zealand. At all of these sites, the planar features in the shocked quartz can be indexed to rational crystallographic planes of the quartz lattice. The grains display streaking indicative of shock in x-ray diffraction photographs and also show reduced refractive indices. These characteristic features of… 
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