Nanodiamonds in the Younger Dryas Boundary Sediment Layer

@article{Kennett2009NanodiamondsIT,
  title={Nanodiamonds in the Younger Dryas Boundary Sediment Layer},
  author={Douglas J. Kennett and James P. Kennett and Alfred P. West and Chris Mercer and Shane S. Que. Hee and Lee Bement and Theodore E. Bunch and Marilee Sellers and Wendy S Wolbach},
  journal={Science},
  year={2009},
  volume={323},
  pages={94 - 94}
}
We report abundant nanodiamonds in sediments dating to 12.9 ± 0.1 thousand calendar years before the present at multiple locations across North America. Selected area electron diffraction patterns reveal two diamond allotropes in this boundary layer but not above or below that interval. Cubic diamonds form under high temperature-pressure regimes, and n-diamonds also require extraordinary conditions, well outside the range of Earth's typical surficial processes but common to cosmic impacts. N… 

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    This research was funded by the NSF (grant ATM-0713769). We thank three anonymous reviewers and V. Haynes for assistance