Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP

@article{Kinzie2014NanodiamondRichLA,
  title={Nanodiamond-Rich Layer across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP},
  author={Charles R. Kinzie and Shane S Que Hee and Adrienne Stich and Kevin A. Tague and Chris Mercer and Joshua James Razink and Douglas J. Kennett and Paul S. Decarli and Theodore E. Bunch and James H. Wittke and Isabel Israde-Alc{\'a}ntara and James L. J.D Bischoff and Albert C. Iii Goodyear and Kenneth Barnett Tankersley and David R. Kimbel and Brendan Culleton and Jon M. Erlandson and Thomas W. Stafford and Johan B. Kloosterman and Andrew M. T. Moore and Richard B. Firestone and J. Emili Aura Tortosa and Jes{\'u}s F. Jord{\'a} Pardo and Allen West and James Peter Kennett and Wendy S Wolbach},
  journal={The Journal of Geology},
  year={2014},
  volume={122},
  pages={475 - 506}
}
A major cosmic-impact event has been proposed at the onset of the Younger Dryas (YD) cooling episode at ≈12,800 ± 150 years before present, forming the YD Boundary (YDB) layer, distributed over >50 million km2 on four continents. In 24 dated stratigraphic sections in 10 countries of the Northern Hemisphere, the YDB layer contains a clearly defined abundance peak in nanodiamonds (NDs), a major cosmic-impact proxy. Observed ND polytypes include cubic diamonds, lonsdaleite-like crystals, and… 
Evidence from Pilauco, Chile Suggests a Catastrophic Cosmic Impact Occurred Near the Site ∼12,800 Years Ago
The Younger Dryas (YD) impact hypothesis proposes that fragments of a large, disintegrating asteroid/comet struck the Earth ∼12,800 years ago. This event simultaneously deposited high concentrations
Comprehensive analysis of nanodiamond evidence relating to the Younger Dryas Impact Hypothesis
During the end of the last glacial period in the Northern Hemisphere near 12.9k cal a BP, deglacial warming of the Bolling–Allerod interstadial ceased abruptly and the climate returned to glacial
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TLDR
In the most extensive investigation south of the equator, a ~12,800-year-old sequence at Pilauco, Chile, that exhibits peak YD boundary concentrations of platinum, gold, high-temperature iron- and chromium-rich spherules, and native iron particles rarely found in nature is reported.
Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact ∼12,800 Years Ago. 1. Ice Cores and Glaciers
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Widespread platinum anomaly documented at the Younger Dryas onset in North American sedimentary sequences
TLDR
Fire-assay and inductively coupled plasma mass spectrometry analyses were performed on 11 widely separated archaeological bulk sedimentary sequences to document discovery of a distinct Pt anomaly spread widely across North America and dating to the Younger Dryas (YD) onset.
Evidence of Cosmic Impact at Abu Hureyra, Syria at the Younger Dryas Onset (~12.8 ka): High-temperature melting at >2200 °C
TLDR
The wide range of evidence supports the hypothesis that a cosmic event occurred at Abu Hureyra ~12,800 years ago, coeval with impacts that deposited high-temperature meltglass, melted microspherules, and/or platinum at other YDB sites on four continents.
A multi-proxy study of changing environmental conditions in a Younger Dryas sequence in southwestern Manitoba, Canada, and evidence for an extraterrestrial event
Abstract Multi-proxy analyses of a sequence spanning the Younger Dryas (YD) in the Glacial Lake Hind basin of Manitoba provides insight into regional paleohydrology and paleovegetation of meltwater
Five Younger Dryas black mats in Mexico and their stratigraphic and paleoenvironmental context
The Younger Dryas interval (YD) was a period of widespread, abrupt climate change that occurred between 12,900 and 11,700 cal yr BP (10,900–10,000 14C BP). Many sites in the Northern Hemisphere
The Younger Dryas impact hypothesis: Review of the impact evidence
Abstract Firestone et al., 2007, PNAS 104(41): 16,016–16,021, proposed that a major cosmic impact, circa 10,835 cal. BCE, triggered the Younger Dryas (YD) climate shift along with changes in human
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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
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TLDR
The presence of shock-synthesized hexagonal nanodiamonds (lonsdaleite) in YDB sediments dating to ≈12,950 ± 50 cal BP at Arlington Canyon, Santa Rosa Island, California is reported, consistent with abrupt ecosystem change and megafaunal extinction possibly triggered by a cosmic impact over North America.
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TLDR
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TLDR
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Abstract We report the discovery in the Greenland ice sheet of a discrete layer of free nanodiamonds (NDs) in very high abundances, implying most likely either an unprecedented influx of
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TLDR
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TLDR
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