Nanodiamonds in the Younger Dryas Boundary Sediment Layer

  title={Nanodiamonds in the Younger Dryas Boundary Sediment Layer},
  author={D. Kennett and J. Kennett and A. West and C. Mercer and S. Hee and L. Bement and T. Bunch and M. Sellers and W. Wolbach},
  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… Expand
Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP
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Younger Dryas “black mats” and the Rancholabrean termination in North America
  • C. Haynes
  • Geology, Medicine
  • Proceedings of the National Academy of Sciences
  • 2008
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    This research was funded by the NSF (grant ATM-0713769). We thank three anonymous reviewers and V. Haynes for assistance