# Is the claimed boundary layer the same age at every site? · Younger Dryas impact hypothesis > Three answers have been proposed. The claimed layers are of different ages, or their ages are not known well enough to say. leads, with evidence 3 for… Source: https://mysteriesdept.com/mysteries/younger-dryas-impact/questions/QST0D51X8JC0DHZ/is-the-claimed-boundary-layer-the-same-age-at-every-site Publisher: Mysteries Department Licence: CC BY 4.0 (credit Mysteries Department and link the page) Updated: 2026-10-26T11:59:09+00:00 --- **0** # Is the claimed boundary layer the same age at every site? Asked 26 Oct 2026 by [**apollo** ](https://mysteriesdept.com/u/apollo)·Part of [Did an extraterrestrial impact or airburst occur at the onset of the Younger Dryas, about 12,800 years ago?](https://mysteriesdept.com/mysteries/younger-dryas-impact/questions/QST0D51X8AJ1304/did-an-extraterrestrial-impact-or-airburst-occur-at-the)·3 answers·0·0 following **Most likely: the claimed layers are of different ages, or their ages are not known well enough to say** Ahead on the evidence, not yet confirmed. It needs two reviews to be accepted. ## Where it stands Three answers have been proposed. The claimed layers are of different ages, or their ages are not known well enough to say. leads, with evidence 3 for: supported by its tests. Two are still possible. Of the one narrower question under it, none is answered yet. ## Why it matters Proponents themselves name synchrony as a key test: a single cosmic event must leave a layer of one age⁠[[1]](https://mysteriesdept.com/sources/SRC0D51WRER0TD5/chronological-evidence-fails-to-support-claim-of-an). It is also where the 2026 retraction of the shocked-quartz paper turned⁠[[2]](https://mysteriesdept.com/sources/SRC0D51WWKJ0X43/retraction-shocked-quartz-at-the-younger-dryas-onset-12-8-ka). ## Answers 3 [**The claimed layers are of different ages, or their ages are not known well enough to say.** ](https://mysteriesdept.com/mysteries/younger-dryas-impact/answers/ANS0D51XE623WP9/the-claimed-layers-are-of-different-ages-or-their-ages-are) Supported by its tests Evidence: 3 for Most likely [**None of these.** ](https://mysteriesdept.com/mysteries/younger-dryas-impact/answers/ANS0D51XF5A3KHP/none-of-these) Not tested enough to call either way Evidence: none yet Still possible [**The boundary layer at all sites dates to 12,835–12,735 cal BP within dating error.** ](https://mysteriesdept.com/mysteries/younger-dryas-impact/answers/ANS0D51XDPE63NW/the-boundary-layer-at-all-sites-dates-to-12-83512-735-cal-bp) Failed a test; not refuted outright Evidence: 1 for Disputed ## History 1. 2014[Meltzer et al. puts forward: the claimed layers are of different ages, or their ages are not known well enough to say.](https://mysteriesdept.com/sources/SRC0D51WRER0TD5/chronological-evidence-fails-to-support-claim-of-an) 1. 2014[Meltzer et al.: several claimed sites have no age control, nearly a dozen use flawed age-depth interpolations, and several…](https://mysteriesdept.com/sources/SRC0D51WRER0TD5/chronological-evidence-fails-to-support-claim-of-an)For: The claimed layers are of different ages, or their ages are not known well enough to say. 1. 2015[Kennett et al. puts forward: the boundary layer at all sites dates to 12,835–12,735 cal BP within dating error.](https://mysteriesdept.com/sources/SRC0D51WRYC7K4H/bayesian-chronological-analyses-consistent-with-synchronous) 1. 2015[Kennett et al.: two statistical tests on modelled and unmodelled ages from 30 records are consistent with synchronous…](https://mysteriesdept.com/sources/SRC0D51WRYC7K4H/bayesian-chronological-analyses-consistent-with-synchronous)For: The boundary layer at all sites dates to 12,835–12,735 cal BP within dating error. 1. 2026[The PLOS One Editors: the retracted shocked-quartz paper omitted available dates, used dates spanning centuries and reported no age…](https://mysteriesdept.com/sources/SRC0D51WWKJ0X43/retraction-shocked-quartz-at-the-younger-dryas-onset-12-8-ka)For: The claimed layers are of different ages, or their ages are not known well enough to say. 1. 2026[The PLOS One Editors: recalibrating the Baffin Bay foraminifera dates by the recommended method moves them outside the Younger…](https://mysteriesdept.com/sources/SRC0D51WWBR25YC/retraction-a-12-800-year-old-layer-with-cometary-dust)For: The claimed layers are of different ages, or their ages are not known well enough to say. 1. 26 Oct 2026Asked on this site ## Discussion 0 [Add to the discussion](https://mysteriesdept.com/signin?next=/mysteries/younger-dryas-impact/questions/QST0D51X8JC0DHZ/is-the-claimed-boundary-layer-the-same-age-at-every-site%23discussion) Help with this question [ **Propose an answer** Something the evidence could support or rule out ] [ **Propose an answer** Something the evidence could support or rule out ](https://mysteriesdept.com/signin?next=/mysteries/younger-dryas-impact/questions/QST0D51X8JC0DHZ/is-the-claimed-boundary-layer-the-same-age-at-every-site%23add-answer) [ **Add evidence** A result for or against an answer ] [ **Add evidence** A result for or against an answer ](https://mysteriesdept.com/signin?next=/mysteries/younger-dryas-impact/questions/QST0D51X8JC0DHZ/is-the-claimed-boundary-layer-the-same-age-at-every-site%23add-evidence) [ **Ask a sub-question** A smaller question that would help settle this one ] [ **Ask a sub-question** A smaller question that would help settle this one ](https://mysteriesdept.com/signin?next=/mysteries/younger-dryas-impact/questions/QST0D51X8JC0DHZ/is-the-claimed-boundary-layer-the-same-age-at-every-site%23add-question) [ **Add a source** A paper, archive record or image ] [ **Add a source** A paper, archive record or image ](https://mysteriesdept.com/signin?next=/mysteries/younger-dryas-impact/questions/QST0D51X8JC0DHZ/is-the-claimed-boundary-layer-the-same-age-at-every-site%23add-source) Where it fits Younger Dryas impact hypothesis [**Did an extraterrestrial impact or airburst occur at the onset of the Younger Dryas, about 12,800 years ago?** ](https://mysteriesdept.com/mysteries/younger-dryas-impact/questions/QST0D51X8AJ1304/did-an-extraterrestrial-impact-or-airburst-occur-at-the)Key question · most likely no impact or airburst occurred; the proposed markers are terrestrial or background cosmic material… [Are the proposed markers (microspherules, nanodiamonds, shocked quartz, meltglass) reproducible and diagnostic of impact?](https://mysteriesdept.com/mysteries/younger-dryas-impact/questions/QST0D51X8T620G9/are-the-proposed-markers-microspherules-nanodiamonds-shocked)Most likely · the markers are background cosmic dust, volcanic or anthropogenic spherules, fire products or misidentified… **Is the claimed boundary layer the same age at every site?** You're here · the claimed layers are of different ages, or their ages are not known well enough to say [ Ask a question under this one ] Under this one [Do the two 2025 PLOS One papers, retracted in February 2026, still add evidence for an impact?](https://mysteriesdept.com/mysteries/younger-dryas-impact/questions/QST0D51X9SE7KQA/do-the-two-2025-plos-one-papers-retracted-in-february-2026)Most likely · the results do not support the conclusions because the age models, sampling and some identifications fail