The Kellaway map of Irish Sea Glacier streamlines. I doubt that any geomorphologists or glaciologists would argue with this map, apart from the suggestions for Somerset and Wiltshire!
A report has appeared in SALON, and while not so biased and garbled as some others in the media, the author (Chris Catling, the Editor?) cannot resist referring to "the probable quarry site." Further, if Ixer and Bevins are correctly quoted, they cannot resist suggesting that the new work now tips the balance towards the "human transport theory" and away from the glacial transport theory.
I do find it rather wearying that archaeologists and geologists persist in the belief that a narrow range of stones at Stonehenge would support the human transport thesis, whereas "the use of different rock types from disparate parts of Wales to create the first stone circle at Stonehenge would support the thesis that the stones were carried by natural means, such as the Irish Sea Glacier." How many times do I have to repeat that that is not how glaciers work? Glaciers do not simply collect up stones from here, there and everywhere, mix them up and then dump them in one place. Glaciers entrain, transport and deposit debris on streamlines, and if stones from disparate sources are entrained and carried they can only come from a narrow band of country coinciding with the streamlines themselves. We know pretty accurately what the streamlines of the Irish Sea Glacier looked like. It is not at all unusual (as I have shown many times on this blog) for glaciers to entrain clusters of boulders from one very limited location and to dump those boulders tens or even hundreds of kilometres away, in another location --- with or without an erratic train joining the two points together. How many times do I have to repeat that, in order for people to understand it?
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Stonehenge bluestones: natural or human transport?
SALON - the Society of Antiquaries of London Online Newsletter
Salon 268: 3 January 2012
In an important new paper published in the journal Archaeology in Wales, our Fellows Rob Ixer, of Leicester University, and Richard Bevins, of Amgueddfa Cymru — National Museum Wales, report on the latest stage in their work to pin down the precise origin of the rhyolitic bluestones that formed the first stone circle at Stonehenge. Having already published a paper in the Journal of Archaeological Science suggesting that the crags of the Pont Saeson area of Pembrokeshire (on the northern flank of the Preseli hills, some 6.5km from Newport) were the likely source, they have now refined their chemical and petrographical techniques to the extent that they have been able to identify a specific outcrop as the probable quarry site.
‘We assumed that we might be able to pin down the source to an area of several hundreds of square metres’, Rob Ixer said, ‘but we can now pin it down unequivocally to an area of a few square metres, namely to a small single outcrop or couple of outcrops at Craig Rhos-y-felin’. The outcrop is some 70m long and has many tall, narrow slabs up to 2m high as the dominant feature, splitting off from the parent rock in blocks that are reminiscent of the Stonehenge bluestones.
The site was found by comparing the chemical properties of stone taken from outcrops in Wales and the west of England with the distinctive bluestone debitage (the waste created by shaping and dressing the stones) excavated in 1947 and subsequently stored in a box at Salisbury Museum. ‘I have always wanted’, Rob Ixer told our Fellow Norman Hammond, Archaeological Correspondent of The Times, ‘to tell this story under the tabloid heading “Old shoebox held key to Stonehenge mystery”.’
Drs Ixer and Bevins also say that their recent work is tipping the balance in the debate about whether or not the stones are glacial erratics. In the ‘nature versus human transport debate’, the higher the number of stones that can be demonstrated to have come from one site, and not from any other, the more likely it is that human agency accounts for their quarrying and transport to Stonehenge. Vice versa, the use of different rock types from disparate parts of Wales to create the first stone circle at Stonehenge would support the thesis that the stones were carried by natural means, such as the Irish Sea Glacier.
Rob Ixer told Current Archaeology magazine that ‘this is the first time that any lithics from Stonehenge have been so clearly provenanced but it will not be the last’. Meanwhile, the hunt continues for the source of four standing Stonehenge orthostats (SH38, SH40, SH46 and SH48) that have been tested and found not to have any petrographical match for any rhyolitic lithology at Pont Saeson — so the story of how and from where the bluestones got to Stonehenge still has some way to run.
20 comments:
Please may we have a glacial expert talking on entrainment of erratic materials at one of the many Archaeological Conferences in 2012? After all, we get specialists on geology and natural history e.g. snails, why not glaciation?
Wonder if this already happens at Scottish Conferences, for example?
Brian,
Quoting from the Salon article in your post,“...distinctive bluestone debitage (the waste created by shaping and dressing the stones) excavated in 1947”
This is the premise that will doom the 'human transport' theory! The 'distinctive bluestone debitage' of foliated rhyolites is not 'the waste created by shaping and dressing the stones' and will not be traced to any standing, laying or buried megalith at Stonehenge! We already know that for the standing stones. All hope is pinned on just one buried stump. But foliated rhyolites are unsuitable for use as 'building stones' (according to your comments in previous posts).
(Dr Ixer should demand he test this buried stump. Before he permits his scientific work be unscientifically used by theologists likes GW. It is a matter of intellectual integrity and commitment to scientific truth)
When we reach that point the question you, I and others have been asking all along will be shouting in their ears: “How and why did these foliated rhyolite fragments get to Stonehenge?”
Kostas
Yes -- I noticed that strange bit about 1947. Goodness knows where that came from -- but maybe that was the date on the shoebox full of fragments which Rob finally had a look at...
The only excavation in 1947 I know of was of the Stonehenge Cursus.
Humpty Dumpty
If the rhyolite fragments tested were from the 1947 excavation of the Stonehenge Cursus, what do these results then have to do with Stonehenge? Imagine if the wrong stones were tested, after all this publicity! There will be many 'eminent experts' with eggs in their faces!
Kostas
Tony, it would depend which geologist they asked.
Seems to me the majority of geologists would NOT support the view that glaciers carried this particular selection of rocks to Stonehenge and dropped them conveniently close by. Reason: no evidence for glaciation in the target area.
I am actually surprised to see Mr Ixer quoted as saying the hypotheses are "balanced". It seems to me that the judgmental scales are still tilted very much towards human transport. Brian should perhaps take this "balance" as a very positive signal that the cause he promotes is being considered as a real alternative.
Chris -- Tony was not suggesting that they ask a GEOLOGIST to talk to them. Geologists know about geology -- they do not necessarily know about geomorphology or glaciology, which are the two disciplines relevant in this case.
I don't care a hoot if there are few geologists who support the glacial transport theory -- the people I care about are glacial geomorphologists. In their ranks there are some who support the theory, and some who do not. (And by the way, neither Chris Green nor Jim Scourse -- whose opinions seem to be valued above all others -- is a glacial geomorphologist.)
And since you are worried about the "lack of evidence" for glacial deposits on Salisbury Plain, would you care to cite for us the evidence which supports the human transport theory? Sorry, but there ain't any, Guvnor.....
Hi Brian,
I recognize your point. My brother and his daughter are both doctors of geology, and I am familiar with the phrase "not my speciality".
When you can convince me that there is abundant evidence for pick-up and deposition of bluestone erratics with, say, 20 miles of Stonehenge - then your theory will carry a lot more weight. This implies 1) any evidence of glaciation effects in the vicinity 2) other erratics deposited by the "stream" on its way 3) unused bluestones from Prescelly lying around in the target area.
You are right that there is no evidence for human transportation either, other than that implied by the apparent ability of these people to move heavy weights over shorter distances. Two negatives do not prove a positive, and it is not only two negatives: we have an abundance of weird and wonderful theories, most of which are less likely than glaciation and all less likely than "humans did it but we don't know how".
My favorite theory is that giants threw the stones in a petulant fit, although this fits fewer facts than most other theories :)
Brian
It would seem that the Glacial transport theory's goose is cooked ??
"The outcrop is some 70m long and has many tall, narrow slabs up to 2m high as the dominant feature, splitting off from the parent rock in blocks that are reminiscent of the Stonehenge bluestones".
Not only is this undoubtedly a Neolithic/Mesolithic bluestone Quarry, but remarkably, one where the stone quarries itself; A remnant of Merlins magic must still exist.
I am not personally surprised, In my delvings in the Mendip Hills, I too have observed such magical phenomena at first hand.
Admittedly: It was when I took my wife to see one of those Harry Potter documentaries at the cinema in Wells;Although I found the evidence for the existence of magical quarries compelling and as valid as that reported by Mr Catling??
I think the balance is shifting towards a Troll transport theory??
(A troll could have carried an orthostat under each arm).
Is Dr Ixer going to be the next Professor of potions, or defence against the dark arts of glacial geomorphology? Is Brian, he who should not be named??
I bet SOMEWHERE on this wonderful planet, glaciology experts [NOT geologists] have been called upon to give their evidence as to the effects of entrainment of glacial erratic materials, in relation to human settlement or monument sites e.g. Canada, the U.S.A., the former Soviet Union, i.e. places where glaciation has had a profound effect on the distribution of rock materials.
AND therefore, if it has happened elsewhere, be it Europe, Asia, or North or South America, then we have examples of the usefulness of glacial/ geomorphological expertise IN TANDEM with other disciplines such as Geology and Archaeology. Somewhere, surely, this has happened/ is happening.....maybe, to some extent, in Northern Europe e.g. Scandinavia.
Here we go again with the obsession for the transportation debate missing the sloppy scholarship that can't even identify the correct excavation. About 15 pieces of welsh rock were found at the Great Cursus - there was no dig at Stonehenge in 1947.
Scientific study? It's certainly not a very scientific paper.
CHRIS
No one really looks for effects of glacial effects on Salisbury Plain, largely because the Plain is occupied by the Army. Although there are Conservation Groups linked to the M.O.D. at Salisbury Plain, they are essentially manned by volunteers, and there is no sub-group for geology/ geomorphology - that is a great pity, but in the real world, not at all surprising. There are, of course, sub-groups for archaeology and wildlife.
Were such a sub-group to exist, then there is a good chance glacial evidence might be found.
I don't think the geologists are confused here -- but the media are. Nothing new there then.....
one area that is overlooked is the area around Warminster where the bluestones would have to cross from the river Avon to the Wyle to get to Stonehenge.
There are two unexcavated henges in this area. Sutton Veny (ST88534192) and Robin Hoods Bower (ST87684234).
If bluestones or fragments were found in this area it would make the human transport idea more plausable.
PeteG
Not sure I follow the logic of that, Pete. Isn't that the general area where Heytesbury (Boles Barrow) is found -- with reputedly not just one but several bluestones contained within it? If other bluestones were found in that area, either inside or outside burial mounds, that would be quite handy evidence in favour of the glacial transport hypothesis -- since I have a gut feeling that the glacier that came in from the west skidded to a halt in that area, against the chalk scarp.
More comments from Kostas blocked.
Alex -- a Troll Transport theory? Well, the Vikings are reputed to have reached Milford Haven, so maybe they brought some trolls with them? Maybe they displaced the local fairies and were summoned by Merlin to work at his command? I like it! I feel another story coming on....
PeteG 'AREA AROUND WARMINSTER'
I have visited both these sites. Robin Hood's Bower has also been suggested as a meeting place for King Alfred and his disparate forces one day before the Battle of Edington near Bratton Camp on the Plain. Is it also a suspected henge, then, Pete? Placename links its location,adjacent to Eastleigh Wood and within Southleigh Wood, with the Anglo Saxon Charter's name for the meeting place, Iglea.
The Salisbury Plain's scarp is no distance at all to the north east from either of the sites PeteG mentions, being close to Battlesbury and Scratchbury Hills, whose steep slopes were recognised when Hill Fort sites were being chosen. So perhaps any glacier might well have come to a halt, along with any erratics being carried, in that general vicinity? Battlesbury Fort has been excavated in recent times, incidentally.
I was thinking that if the bluestones were hauled overland at this point then they would have had to cut down a lot of tree's so there should be broken axes (possibly bluestone) and bits that fell off the stones being dragged over a small area between the rivers.
PeteG
Yes, a fair enough point, Pete.
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