At https://dailygalaxy.com/2026/05/a-42000-year-old-asteroid-crater-in-south-korea-created-a-hidden-lake-where-ancient-life-may-have-later-emerged/ …. this one caught my eye because of the date assigned to the Hapcheon Impact Crater in South Korea – 42,000 years BP. This date is derived from C14 methodology applied to charcoals within the impact breccias at 100 m to 140 m depths. I don’t know how reliable that C14 date is but left as it is it implies it occurred contemporary with the Laschamp Event. This is dated by C14 to 42,000 years ago. However, the application of IntCal Bayesian methodology has taken that date back to anything between 45,000 and 50,000 years ago. This article seems to imply a date of 55,000 years ago – if I am reading it correctly. The distinct differences in C14 and Bayesian techniques is quite striking. The date of 42,000 years ago was always the buffer zone of the C14 methodology as the Laschamp Event pumped so much of the stuff into the atmosphere it was impossible to date anything earlier. This should also be taken into consideration. The Laschamp Event is known as a temporary magnetic reversal – that righted itself after a few hundred years. A uniformitarian equation which may indicate it was really reversed back again more quickly. Laschamp also involved a mass die off of land animals – and a depopulation in Neanderthal and Denisovan numbers, our immediate human ancestors. One impact crater in South Korea cannot account for all that.
The research concentrated on layered mineral structures known as stromatolites. These are a fairly recent study focus as the asteroid bombardment on early Earth is speculated to have produced evidence of stromatolites in ancient rocks. This has been stoked by the idea they may have triggered active oxygen that led to the creation of habitable environments for life on Earth. No evidence a oxygen generation was found in this research, however – but stromatolites were. See https://www.nature.com/articles/s43247-026-03206-7 … and you may also like to look at what was found at a crater in Finland, on the same subject of stromatolites – see https://www.nature.com/articles/s41467-025-63603-y … Stromatolites are produced by microbial mats but they seem to have formed long after the impact date. They formed in the crater, however. The researchers went on to establish that the crater, or basin, was once a lake for a long period of time. The stromatolites were found in sediments left behind by the lake. It seems it was a hydro thermal lake going by the chemistry – and possibly triggered by the impact event. Here is where C14 analysis enters the story once more. This indicates the stromatolites formed, or were thriving, between 23,400 and 14,600 years ago. These dates are also of interest – even more so as an outlier date of 28,320 is also mentioned. The Late Glacial Maximum followed on from a second mass die off and the complete disappearance of Neanderthals and Denisovans, dated around 33,000 years ago. In Australia the mass die off of mega animals occurred at this time rather than at the end of the Late Glacial Maximum. So, why would stromatolites thrive in a hydr0thermal lake during the coldest era in recent earth history? Ice sheets advanced in NE North America and in NW Europe. What was going on in Korea? Or China? Was it equally as dismal as it was in Europe? Or was it warmer and more agreeable. The dates of 23,400 to 14,600 years ago seem to cover a large part of the LGM, given the stromatolites may not have burst into growth until the conditions were right. They thrived deep into the Oldest Dryas Event [sometimes known as Heinrich One] and out the other side into the warmer period that followed.