The Younger Dryas impact hypothesis: a cosmic catastrophe

  title={The Younger Dryas impact hypothesis: a cosmic catastrophe},
  author={Vance T. Holliday and Todd A. Surovell and David J. Meltzer and Donald K. Grayson and Mark Boslough},
  journal={Journal of Quaternary Science},
In this paper we review the evidence for the Younger Dryas impact hypothesis (YDIH), which proposes that at ∼12.9k cal a BP North America, South America, Europe and the Middle East were subjected to some sort of extraterrestrial event. This purported event is proposed as a catastrophic process responsible for: terminal Pleistocene environmental changes (onset of YD cooling, continent‐scale wildfires); extinction of late Pleistocene mammals; and demise of the Clovis ‘culture’ in North America… 
Premature rejection in science: The case of the Younger Dryas Impact Hypothesis.
  • J. Powell
  • Environmental Science
    Science progress
  • 2022
Evidence is presented that the Younger Dryas Impact Hypothesis (YDIH) is a twenty-first century case and why scientists so readily accepted the early false claims of irreproducibility and what lessons the premature rejection of the YDIH holds for science are presented.
A Blind Test of the Younger Dryas Impact Hypothesis
A test reported here presents the results of analyses that address questions about Reproducibility of at least some analyses of purported impact indicators, finding that no standard criteria exist for identification of magnetic spheres and the purported impact proxies are not unique to the YDB.
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 Bølling–Ållerod interstadial ceased abruptly and the climate returned to glacial
Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact ∼12,800 Years Ago, Parts 1 and 2: A Discussion
Wolbach et al. published two papers on the Younger Dryas Impact Hypothesis (YDIH)—the paleoenvironmental effects of a purported cosmic impact at the beginning of the Younger Dryas Chronozone (YDC).
Sedimentary record from Patagonia, southern Chile supports cosmic-impact triggering of biomass burning, climate change, and megafaunal extinctions at 12.8 ka
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.
The Younger Dryas interval at Wonderkrater (South Africa) in the context of a platinum anomaly
INTRODUCTION The Younger Dryas (YD) event is recognized especially well in the northern hemisphere as an episode of cooling, the inception of which is circa 12 800 years BP (calibrated date), lasting
Interpreting palaeofire evidence from fluvial sediments: a case study from Santa Rosa Island, California, with implications for the Younger Dryas Impact Hypothesis
Fluvial sequences from the late Pleistocene to the Holocene are exposed in Arlington Canyon, Santa Rosa Island, Northern Channel Islands, California, USA, including one outcrop that features
Problematic dating of claimed Younger Dryas boundary impact proxies
  • V. Holliday
  • Environmental Science
    Proceedings of the National Academy of Sciences
  • 2015
The PNAS paper by Kennett et al. (1) uses statistical methods in an attempt to improve the geochronological control for purported Younger Dryas boundary (YDB) impact proxies. The underpinning data
Catastrophism through the ages, and a cosmic catastrophe at the origin of civilisation
Developments in the Earth Sciences over the last decade point towards a great cosmic catastrophe at the onset of the Younger Dryas period, towards the end of the Paleolithic. It has been suggested
Late Quaternary megafaunal extinctions on the continents: a short review
  • A. Stuart
  • Environmental Science, Geography
  • 2015
This paper provides an overview of the contentious issue of global megafaunal extinctions in the Late Quaternary. The main proposed causes are ‘overkill’, environmental change or a combination of


The Younger Dryas impact hypothesis: a critical review
Arguments and Evidence Against a Younger Dryas Impact Event
We present arguments and evidence against the hypothesis that a large impact or airburst caused a significant abrupt climate change, extinction event, and termination of the Clovis culture at 12.9
Absence of geochemical evidence for an impact event at the Bølling–Allerød/Younger Dryas transition
The data show no evidence of an extraterrestrial (ET)-PGE enrichment anomaly in any of the investigated depositional settings investigated across North America and in one section in Belgium.
Chronological evidence fails to support claim of an isochronous widespread layer of cosmic impact indicators dated to 12,800 years ago
The Younger Dryas Impact Hypothesis fails the critical chronological test of an isochronous event at the YD onset, which, coupled with the many published concerns about the extraterrestrial origin of the purported impact markers, renders the YDIH unsupported.
Paleoindian demography and the extraterrestrial impact hypothesis
The study reports a study in which ≈1,500 radiocarbon dates from archaeological sites in Canada and the United States were used to test the hypothesis that the ET resulted in population decline among the Paleoindians and suggested the extraterrestrial impact hypothesis should be amended.
No evidence of nanodiamonds in Younger–Dryas sediments to support an impact event
The results cast doubt upon one of the last widely discussed pieces of evidence supporting the YD impact hypothesis, as it is demonstrated that previous studies misidentified graphene/graphane-oxide aggregates as hexagonal diamond and likely mis identified graphene as cubic diamond.
Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis
Elevated concentrations of iridium in bulk and magnetic sediments, magnetic spherules, and/or titanomagnetite grains within or at the base of black mats are found, suggesting that elevated concentrations of these markers arise from processes common to wetland systems, and not a catastrophic extraterrestrial impact event.
Younger Dryas “black mats” and the Rancholabrean termination in North America
  • C. Haynes
  • Environmental Science, Geography
    Proceedings of the National Academy of Sciences
  • 2008
Of the 97 geoarchaeological sites of this study that bridge the Pleistocene-Holocene transition (last deglaciation), approximately two thirds have a black organic-rich layer or “black mat” in the
An independent evaluation of the Younger Dryas extraterrestrial impact hypothesis
An independent analysis of magnetic minerals and microspherules from seven sites of similar age finds no support for Younger Dryas extraterrestrial impact.
Large Pt anomaly in the Greenland ice core points to a cataclysm at the onset of Younger Dryas
A large Pt anomaly is found at the YDB, not accompanied by a prominent Ir anomaly, with the Pt/Ir ratios at the Pt peak exceeding those in known terrestrial and extraterrestrial materials.