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Indefatigable genius and digital friend of the Tusk, Dr. Martin Sweatman of the University of Edinburgh, authored a surprise blockbuster this week. Below from Earth Science Reviews is a peer-reviewed and fully accepted synthesis overview of the Younger Dryas Impact controversy since the very first paper in 2007.
‘The Younger Dryas impact hypothesis: review of the impact evidence‘ concludes — in the most appropriate and respected global earth science journal — that based on the published evidence, our modern world is indeed birthed of a horrendous global catastrophe (~12,827 years ago, Late June). It is a lengthy, detailed, fair and lucid tour-de-force in support of The Event based on Martin’s reading of the entire debate.
Martin is an example to the Tusk of how many, many people there are on Earth. You gotta have at least 8+ billion humans in order to have just enough brain matter and grit on the end of the bell curve to find one, well-qualified, unbiased, poly-curious scientist, so determined to find the truth that they will read every last word — and write every last word well.
Younger Dryas Impact fans and the newly curious will spend some time soaking in Martin’s piece. Its long, and intricate at times, but it’s far more readable to a larger audience than the technical literature it discusses.
One thing is for sure, if someone can only read a single peer-reviewed paper concerning the Younger Dryas Impact, Martin’s article is perfect. And if they can only read two? It will be a long wait for another to refute his conclusions.
Here is the entire in-press, pre-publication article at Martin’s website.
Martin’s 21-Part YouTube series on the YDIH debate
Younger Dryas impact review paper accepted by Earth-Science Reviews
This article is now accepted in the top Earth-Science journal, Earth-Science Reviews.
The Younger Dryas impact hypothesis: review of the impact evidence
Martin B. Sweatman, Institute of Materials and Processes, School of Engineering, King’s Buildings, University of Edinburgh, UK. EH9 3FB
Keywords: cosmic impact, Younger Dryas, platinum anomaly, impact microspherules, nanodiamonds, climate change, Clovis culture, megafaunal extinctions
Firestone et al., 2007, PNAS 104(41): 16016-16021, proposed that a major cosmic impact, circa 10,835 cal. BCE, triggered the Younger Dryas (YD) climate shift along with changes in human cultures and megafaunal extinctions. Fourteen years after this initial work the overwhelming consensus of research undertaken by many independent groups, reviewed here, suggests their claims of a major cosmic impact at this time should be accepted. Evidence is mainly in the form of geochemical signals at what is known as the YD boundary found across at least four continents, especially North America and Greenland, such as excess platinum, quench-melted materials, and nanodiamonds. Their other claims are not yet confirmed, but the scale of the event, including extensive wildfires, and its very close timing with the onset of dramatic YD cooling suggest they are plausible and should be researched further. Notably, arguments by a small cohort of researchers against their claims of a major impact are, in general, poorly constructed, and under close scrutiny most of their evidence can actually be interpreted as supporting the impact hypothesis.
An excerpt from the concluding paragraphs:
Another common strategy used by opponents has been to make misleading spurious and fallacious arguments, leading, in one case, to the claim that the proposed impact scenario is unlikely to have ever occurred over the whole lifetime of the universe (Boslough et al., 2013). Of course, these statistics do not actually apply to the proposed impact scenario, but rather to a scenario invented by the opposing authors (Napier et al., 2013). Likewise, it is frequently argued that wildfires might produce nanodiamonds (van Hoesel et al., 2014; van Hoesel et al., 2013). However, there is no single case documented where this is known to have occurred, and, of course the counter-argument is obvious; if wildfires could produce nanodiamonds, they would be ubiquitous and abundant in sediments, as for charcoal. But they are not. Nor can wildfires explain the abundance of nanodiamonds in Greenland’s ice. Strangely, it has even been argued that cosmic impacts do not produce extensive wildfires (Holliday et al., 2020b), an obviously incorrect argument on physical grounds. Other fallacious arguments against the impact hypothesis include the occurrence of multiple black mats with a few similar geochemical signals (Pigati et al., 2012). But it is clear the YDB evidence must be considered on its own terms, and, in any case, multiple cosmic impacts, or unrelated volcanic eruptions, over a 40,000-year timespan should not be so hastily ruled out. Moreover, when attempting to reproduce purported evidence for a cosmic impact, it is important that similar samples from exactly the same stratum at the same site are taken. Daulton et al.’s (2010) search for nanodiamonds appears to be hamstrung by this issue, an error these researchers seem determined not to admit (Scott et al., 2017).