This is a cracker as they say. At https://www.livescience.com/planet-earth/volcanos/supervolcano-megabeds-discovered-at-bottom-of-sea-point-to-catastrophic-events-in-europe-every-10000-to-15000-years … notice the word ‘catastrophes’ in the headline – in fact, it is the crunch line. Mainstream commenters might not be happy with that. The discovery of megabeds on the sea bottom is expanded to every 10,000 to 15,000 years. We all know that cycles could have a connection with orbits – but the invoker of the supervolcanoes is studiously ignored. They just happen, it seems. Once every ten to fifteen thousand years. Although the numbers don’t seem to add up when you look at them. This sounds a bit like a book title of a few year’s back. Fred Singer claimed climate change occurred every 1500 years. However, that cycle was dated to the Holocene period, and 15,000 years was reduced ten fold to 1500 years. You can take this sort of thing with a pinch of salt – but what has been discovered.
Four large deposits from super volcanic outbursts, or a sudden bout of super activity, over the last 40,000 years, have been found on the bottom of the Mediterranean. The megabeds theefore dwarf deposits of lesser volcanos – such as Etna, one might imagine. These must be really big deposits. That is why they are described as mega – as in very big geological hand prints of extremely active volcanic activity.
The discovery came about as a result of research into geo hazards off the coast, mostly the Italian offshore region. Sediment was laid down between each mega bed, which implies things returned to normal for periods before the next megabed was laid down. Underwater imaging was also used. What amplifies the severity of these events is that they were between 33 and 82 feet thick, each one separated by large quantities of accumulated sediment. Cores drilled into the beds showed they had an origin in volcanic material. What might have provoked such activity?
The oldest megabed was dated around 40,000 years ago – which coincides with the Laschamp event which involved a geomagnetic reversal and a mass die off of animals and humans. It was not confined to the Mediterranean. The next megabed was dated at 32,000 years ago. No surprise again as this coincides with the beginnings of the Late Glacial Maximum – and evidence of mass die off again, and the disappearance of very large animals in Australia. The third one coincides with 18,000 years ago, and therefore perhaps with the Gothenberg geomagnetic anomaly. It also represents the end of the Late Glacial Maximum and the end of the Ice Age as it is defined in geological terms. It also coincides with the Oldest Dryas Event, 18,000 to 15,000 years ago, that arrived in the wake of the LGM. Sometimes it is referred to as Heinrich Event One. However, there is no volcanic megabed associated with the Younger Dryas event it would seem as the fourth megabed is dated to 8000 years ago = the 6200-6000BC event, which may also have had a geomagnetic connection. Or a movement of the earth’s dipole. In other words, this new finding supports the chronology of catastrophism as noted from data on land. The fact that changes in the dipole may correspond with movements at the poles might explain the extreme volcanism. Or of course, it may not. A lot more evidence of this kind is required – but will anyone look for it?
Then we have a report on volcanic activity on Iceland – magma seeping into a tectonic fracture zone. See https://www.livescience.com/planet-earth/volcanos/why-is-iceland-so-volcanically-active-a-geologist-explains … the geologist goes on to say that Icelandic volcanoes are quite tame in comparison with others in different parts of the world. They are not explosive. They mainly involve upwelling of magma from what is the Mid Atlantic Ridge – thought to be pushing two plates away from each other.