The "traditional" map of known ice movement directions as it was around 1900. In several sectors subsequent research has shown a more extensive ice cover. HH Thomas must have known this map, but chose to misrepresent it. The evidence base for ice movements on the western flank of Great Britain has always been stronger than the evidence base for the east coast.
As far as I can see, the latest suggestion relating to the glacial transport of the Altar Stone from northern Scotland to the Dogger Bank has been broadly accepted by the Stonehenge archaeology establishment. At least, nobody has come out in opposition to the idea, although there have been a few murmurs about the rather fanciful Dogger Bank / Dogger Island part of the narrative.
Clarke, A. J. I., Veness, R. L. J., Kirkland, C. L., Clark, C. D., Gandy, N., Emery, A. et al. (2026) From Highlands to Henge: Refining the Provenance and Transport Pathways of Stonehenge's Altar Stone. Journal of Quaternary Science, 1–8.
https://doi.org/10.1002/jqs.70080 https://onlinelibrary.wiley.com/doi/epdf/10.1002/jqs.70080
So we now have a "hybrid theory" for the east coast of Great Britain, with the acceptance of the idea that the Altar Stone may well be a large glacial erratic, transported on at least part of its journey by south-flowing glacier ice. There are no other known ORS monoliths on Salisbury Plain that can be matched to the Altar Stone, and there is no known erratic trail from A to B. As noted by Clarke et al, it might be there, but if it is there it is very conveniently situated on the floor of the North Sea.......... out of sight and out of mind. So the speculation cannot be contradicted by hard evidence.
Now we come to the entertaining bit. Over the course of more than a century geologists like Judd, Kellaway and Williams-Thorpe have argued that something similar happened on the west coast of Great Britain, with the Irish Sea Ice Stream transporting a wide array of glacial erratics from sources along its known route and dumping some of them on the floor of the Bristol Channel and others above present sea level on the coasts of South Wales, Devon, Cornwall and Somerset. Ice movement directions are well known, and erratic provenances are broadly agreed by the experts. The evidence is well described in the literature, and is undisputed by glacial geomorphologists.
But it is bizarre, to put it mildly, that archaeologists -- and especially those who are influential in Stonehenge circles -- insist that the glacial transport of the bluestones was impossible, basing that outrageous belief on a very dodgy statement by HH Thomas back in 1923 that the ice of the Irish Sea Glacier could not have extended much further than the coast of South Pembrokeshire. He invented the human transport hypothesis, and a large part of the academic establishment and the Stonehenge media machine has promoted that as "the truth" ever since.
On the basis of Thomas's dishonesty the human transport of the bluestones has been ruthlessly promoted as "the only story that makes sense", with MPP and his colleagues developing an ever more complex and fanciful narrative (involving quarries, lost stone circles etc) and with the backing of geologists like Bevins and Ixer, who should be ashamed of themselves. The bandwaggon has also made room for one or two geomorphologists, who shall be nameless.
So the glacial transport of large lumps of rock is OK off the east coast, but not off the west coast. This is hilarious, pathetic, outrageous and reprehensible in equal measure.
The only story that respects the evidence and makes sense is the hybrid one, involving glacial erosion, entrainment and erratic transport as part one of the bluestone monolith journey, and then human transport for the last part of the journey from several locations yet to be discovered, through to Stonehenge. Those locations WILL be found, and that is where future research should be concentrated.
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Quote from one of my earlier posts:
All things considered, the accumulated evidence shows that by 1910 the broad outlines of glaciation in the Bristol Channel / Celtic Sea arena were already established, involving thick and active ice carrying erratics and other glacial materials from the NW across Pembrokeshire and up the Bristol Channel, affecting the coasts of South Wales and the South-West Peninsula. In making his claims about the impossibility of bluestone transport towards Stonehenge HH Thomas wilfully ignored a great amount of evidence in the printed literature, and wilfully misrepresented the opinions of senior "glacialists". It is quite extraordinary that he got away with it -- but that, maybe, was because he was a geologist talking to archaeologists or antiquarians. If he had been a geologist talking to other geologists, he would certainly not have got away with it. They would have had his guts for garters.
It's worth saying the western route for an Altar Stone erratic isn't closed off by the Clarke work. It's just been passed over.
ReplyDeleteTheir data securely points to a Laurentian source, north of the Iapetus Suture. Orcadian specifically? Not really.
Several candidates on the western side never got a proper case-by-case test.
The north Irish ORS outcrops at Clew Bay, Cushendall, Curlew Mountains and Fintona, and the Southern Lake District right on the Suture. (Not mentioning all the pockets totally eroded away.)
Any of these fits comfortably within the Irish Sea Ice Stream's catchment.
The same ice that dumped Ailsa Craig on Gower and shoved Anglian ice into Somerset and Devon around 450,000 years ago.
So the Irish Sea Ice Stream pathway is still on the table.