The block of upland between the Herefordshire Golden Valley and the Wye river valley is fast becoming revealed as the hosts of an integrated Neolithic ceremonial landscape. See https://phys.org/news/2021-08-archaeologists-reveal-famous-stone-age.html … Arthur's Stone has a massive capstone raised on a series of supporting but lesser stones. However, the monument, it seems, originally extended into a field to the south of the tomb. It had first been a long mound, or barrow, comprised of stacked turf retained by a palisade of upright wooden posts surrounding the mound. Later, when the posts had rotted away and the mound had sunk inwards, an avenue of larger posts was added, leading from the Golden Valley up to the mound.
The initial mound pointed towards Dorstone Hill, in the 4th millennium BC, but the revised mound had a different orientation, looking out towards the far horizon. It seems to point to a gap between Skirried and Garway Hill to the SE. The turf mounds themselves were built on the footprint of a large timber building, or hall. These are known as 'halls of the dead'.
At https://phys.org/news/2021-08-massive-ancient-lake-praires-quickly.html … or www.ualberta.ca/folio/2021/08/massive-ancient-lake-across=praires-emptie… … geologists have been researching sediments in Alberta which appear to show a huge channel was cut through Quaternary deposits as far down as the Alberta tar sands. Elsewhere this stratum is deeply buried but in what appears to have been a water carved channel they are visible and accessible. The origin of the water is believed to be Laka Agassiz, and idea derived to account for a body of water required to kick start the Younger Dryas cooling event. It was thought cold glacial water could do that – even though several thousand years had elapsed since the Ice Age. The big question we might ask – where did all the water come from – and is it certainly dated to the onset of the Younger Dryas rather than a few thousand years earlier.
Geomorphological evidence from northern Alberta suggests there was a very large flood of water that swept through the Clearwater-Athabaska Spillway. It then ran through the McMurray region of Alberta and into the Mackenzie River basin – and out into the Arctic Ocean [it is thought]. . It is assumed the spillway had an origin in Lake Agassiz. Mainstream theory is that the lake developed as the ice sheet that covered the Canadian Shied gradually melted. What if that melting had occurred much more quickly? P{erhaps both ideas are pertinent. Previously, it was believed glacial cold water poured down the St Lawrence river valley into the North Atlantic, causing the Younger Dyas cooling. This idea was dropped as there was little evidence of a torrent of water scouring the St Lawrence – but plenty of evidence of a flood of water pouring southwards through the Mississippi River valley. It then became the craze to think in terms of a flood northwards via the Mackenzie River. This piece of research falls into that pattern of thinking. However, they seem to have hit the bullseye in Alberta. Water seems to have been flowing in all directions. That may favour a rapid melting of the ice sheet. We shall have to wait and see.
The research team set out to estimate the rate of flow. It was massive. Some two million cubic metres of water every second a the height of the flood. A total of 2.00 cubic kilometres of water in less than 9 months – the equal of all the water now in the Great Lakes. It is assumed the water came from an overtopping of Agassiz. Is that viable?