How much do we know about Stonehenge? Less than we think. And what has Stonehenge got to do with the Ice Age? More than we might think. This blog is mostly devoted to the problems of where the Stonehenge bluestones came from, and how they got from their source areas to the monument. Now and then I will muse on related Stonehenge topics which have an Ice Age dimension...
Pages
▼
Saturday, 30 June 2018
Out with the fairies on the Great Stone Road
More press coverage of the latest twist in the bluestone transport narrative. No matter how deeply
you dig, you will find no new evidence here. It simply appears that the geologists Ixer and Bevins were determined to say something new, for reasons that are unclear.......... could a new book on the bluestones have had anything to do with it?
http://www.dailymail.co.uk/sciencetech/article-5899227/Has-secret-Stonehenge-solved.html
In the wonderful map showing the “great stone road” and the other “bluestone route” options, there is not a scrap of evidence in support of any of them, as I have pointed out in my book. The thesis seems
to be this: glacial transport was impossible, therefore the stones were manhandled across country or across the sea, therefore there must have been a route, and our route might just be a better one than anybody else’s.........
The route speculators have been playing games ever since HH Thomas started the craze in 1921 — playing on the gullibility of the public and the naivety of the media. Nothing, apparently, changes....... and those who play the route game are as cynical as ever.
The only thing that is “new” is the map of the Senni Beds reproduced in the Antiquity article. But there is nothing in that map or in any associated research to point to Hay on Wye as the source area for the Altar Stone or for any other bits of debitage at Stonehenge. Until the geologists have more evidence to give us about the sandstone monoliths and debitage, and about the precise characteristics of the Senni Beds, why don’t they just keep quiet?
Friday, 29 June 2018
Geologists in fantasy land
Thanks to Alex for bringing this to my attention. Norman Hammond is the reporter responsible for this complete nonsense — but who fed this stuff to him? Why, none other than our old friends Rob Ixer and Richard Bevins........
It presumably came from a press release associated with the recent paper on HH Thomas and on another recent paper in “Antiquity” which I shall shortly take a look at. But there was no new evidence in either paper relating to the Altar Stone or to bluestone provenances, so this article is based on no evidence whatsoever. This is nothing short of wild fantasising, and I cannot for the life of me understand why two respectable geologists have allowed themselves to be dragged into, and cited in, this sort of gutter journalism.
=============
PS. Mind you, I'm a fine one to talk -- some of the press coverage when my new book was published was quite incredible! The Daily Mail article was a thing to behold. Then the coverage in all those newspapers in the Australian outback was especially wonderful. But I did at least send out to the press a carefully written press release which they then did terrible things to. In the case of this Times article, I think Norman Hammond is probably reflecting quite closely what he was told.....
Tuesday, 26 June 2018
Posting problems
Excuse me, faithful readers, but I am having problems with Blogger again. They have still not fixed the problem relating to Email notifications of comments, and there is another problem relating to the composing and editing of posts. Scrolling is impossible when using an iPad, and I cannot add photos in the same way as I did when using my faithful old MacBook. So some posts may end up being very messy and devoid of images......
Google and Blogger are looking rather incompetent these days......
Google and Blogger are looking rather incompetent these days......
Monday, 25 June 2018
Spotted dolerite and retail therapy
Did you know that you can do wonders for your health by buying big lumps of bluestone? Thanks to Chris for this piece of intelligence from the Netherlands:
“I was shopping for some crystals on Saturday and saw the enclosed. Looks like genuine spotted dolerite for 50 Euros per kilo. The owner of the store has published a book in which "Preseli Blauwe steen" is described as being useful for the third eye.
Description:
"Helps to let go of emotions. Stimulates you to go and do something. This stone comes from the Stonehenge area. It helps to surface old memories. Balances the bodily energies. Stone that can transport you to the underworld and to the heavens. Used to return a portion of soul that you lost in previous lives."
This certainly looks like genuine bluestone. It’s been broken off a larger block with a heavy hammer, by the look of it. We know that there are several entrepreneurs who sell bluestone lumps collected in Preseli, bluestone “crystals” and bluestone “jewellery” —You can track them down by doing a simple Google search. Again, the prices are sky high. As we have reported on this blog, the National Park staff are on the record complaining about people who collect up bits of bluestone from the Carn Meini area in particular. But there is no law against people who collect and sell bluestone lumps that have come from private land on the south side of Preseli — and there are of course abundant boulders waiting to be “farmed”....
But the interesting thing about the stone discovered by Chris is that it is claimed to have come “from
the Stonehenge area.” Did somebody really collect it from near Stonehenge? If so, I’m sure EH would be rather interested to know where it came from!
Thursday, 14 June 2018
Historic document from 2000
This reminds us that when the pullers started with the project, all wore yellow gloves and PULLED on the ropes. But many found that very hard work, getting rope burns and blisters on their hands -- and so after a while the organisers developed a sort of harness for each puller, with a bar in front of the chest and a connection behind onto the main haulage rope. So those who were drawing the stone along were facing forward and PUSHING -- and were able to use their body weight much more effectively. The men with the levers who walked along behind the stone were there to lever the loaded sledge back into position when it slid sideways -- as it did with alarming frequency.
In spite of these innovations, and the use of modern ropes and friction-reducing Netlon to increase sliding efficiency on asphalt roads, the stone pull was still an unmitigated disaster, proving without a doubt to all of those involved that the hypothetical human haulage of 80 bluestones from Presell to Stonehenge was just about as reliable as the "aliens from outer space" hypothesis.
Wednesday, 13 June 2018
Meanwhile, in the Brecon Beacons
Thanks to Phil for 4 images of the cirque called Craig Cerrig-gleisiad (glitter-stones crag) in the Brecon Beacons.The top one looks south into the Taff Valley; the second one looks out of the cirque, over the lip, towards Brecon and Hay on Wye in the distance; the third looks into the cirque, with the headwall in the distance. The last photo, below, shows the inside of the cirque with Pen y Fan and Corn-du in the distance.
There are some very spectacular glacial features in the Beacons, all well recored and studies over the years. The ice divide in this area seems to have been very mobile -- apparently shifting about in all compass directions during the course of the Devensian.
Monday, 11 June 2018
More from the ice divide
Purely by chance, this was posted on Facebook today by Stephen John (no relation). Fabulous image -- taken on the remote upland road to the Elan Valley. Again, this is typical ice divide terrain, maybe covered by relatively stagnant and cold-based ice for most of the Devensian cold episode. That means maybe 50,000 years of ice cover, with remarkably little landscape modification.
Craig Rhosyfelin -- "the monolith extraction point" -- again
Fracture scar left when a small slab (maybe 5 cms thick and c 20 cms wide) fell away relatively recently. The scar edges are sharp and fresh.
I applied some close scrutiny to the "monolith extraction point" at Rhosyfelin on my last visit -- referred to by Mike Parker Pearson and colleagues as located in a "recess." There isn't any recess there, and there is no evidence at all that a single stone might have been taken from the point at which MPP has charmingly posed for a thousand photographs.
As I have pointed out before, the rock face here has several prominent fracture scars which must have been created when small slabs of foliated rhyolite fell away and accumulated at different times at the foot of the crag. If they were present in 2011, these must all subsequently have been carted away and dumped by the archaeologists, who were interested above all else in the 5 years of digs in looking for monoliths capable of being carted off to Stonehenge or to "proto-Stonehenge". It's possible, of course, that some of the slabs broke away while the site was affected by glacier ice and torrents of meltwater; they may have been incorporated into overriding ice, or moved downstream before being dumped. They must all have been quite small, and easily modified or destroyed.
A very old fracture scar on the same face; note how heavily abraded the outer edge of the scar is. The slab that dropped away from above it must have parted company wit the rock face many thousands of years ago.
Another clean fracture, also heavily abraded. A late Devensian feature?
Irregular fracture scars towards the base of the exposure. Several slabs have fallen away here, one c 6 cms thick and probably another around 4 cms thick. Again the scars are heavily abraded -- suggesting the action of either ice or meltwater.
The sample that was taken away for cosmogenic exposure dating about 3 years ago must have come from somewhere on this face. The dating must have been completed long since -- I wonder why the result has never been published? But then nobody likes to publish inconvenient evidence, do they?
More comments about the book....
Two more comments from senior academics. (By the way, I did not make them up.) I'm quite encouraged. Of course, there will be negative and aggressive reviews in assorted journals from people with vested interests and maybe from some who don't wish to take my arguments on board. Such is life....
"..........your recent book The Stonehenge Bluestones. Excellent! I believe you! I read it from cover to cover. Your demolition job on the Bluestones did me good. ‘Assumptive research’ is more common than one might expect … and embedded assumptions create vast barriers, dams, holding up research … YET flexibility is unwelcome!"
"Only had a quick browse so far but seems you've done a grand job updating... Excellent stuff."
Thursday, 7 June 2018
Stonehenge -- rhyolite in a Mesolithic context?
Pit 9580 -- from p 46 of Cleal et al, 1995
On looking through Ros Cleal's mammoth tome the other day, I came across a rather interesting reference to a "rhyolite chip" in what appears to be a Mesolithic context. This would not, of course, be the first time that a piece of bluestone has been uncovered in a pre-Stonehenge context.......
In Chapter 4 ("Before Stonehenge") Michael Allen makes use of the unpublished notes of Martin Trott, working for Wessex Archaeology at the behest of English Heritage, to study those famous post holes in the old Stonehenge car park.
In Pit 9580 (the easternmost pit, very close to the old Visitor Centre), there was a very varied fill of sediments about 1.3 m thick. The pit seems to have been re-cut and modified several times, the most prominent modification being a transformation into a wide shallow pit (purpose unknown) just 70 cms deep. Trott described primary, secondary and tertiary contexts. The most interesting thing about the recut tertiary fill at the top of the sequence (context 9581) is that it contained a piece of rhyolite weighing 62g, at a depth of 20 cm. Then we come to some circular reasoning -- Allen says: "this latter find is of some significance as it indicates that this layer was not earlier than, and was probably contemporary with, the dressing of the bluestones (phase 3)." That is one explanation -- the other is that the rhyolite chip was there when the pit was in use, or was being filled in, very much earlier than Bluestones Phase 3. This latter explanation is supported by the radiocarbon date of 8400 +/- 100 yrs BP obtained from charcoal in the tertiary fill layer. The layer is pretty well homogenous, and there is no reason to think that the rhyolite chip was introduced and buried here more than 3,000 years after the Mesolithic pit was finally filled. If it had been, there should be signs of some break in the stratigraphy.
Then it gets even more confusing, since detailed work on the molluscan fauna and on pollen analyses from the side of the opened pit indicate a "hiatus" between the lower parts of the pit fill and the "tertiary fill" near the surface. Allen and other researchers suggest that there was indeed a break of as much as 5,000 years between the Mesolithic and Neolithic activity. In the Mesolithic (Boreal) period there was a wooded landscape, and when the sediments of the tertiary fill were emplaced the landscape was much more open. But is that assumption of a long hiatus based upon the assumption that rhyolite cannot possibly have been present in the neighbourhood during the Mesolithic? Could the clearance of land and its transformation from open woodland to a grassland area have taken place rather quickly -- or over a few thousand years -- during the Mesolithic, as a result of burning? Should we believe the radiocarbon date, or treat it as an aberration?
This is all very intriguing -- does anybody have more information?
Ice shed country -- Cambrian Mountains
Llyn Cwm-byr, near Pumlumon
I keep on discovering fascinating landscapes. I discovered another one the other day, while travelling home from giving a talk in Bishops Castle, in the Welsh Borders. We took detour off the Newtown - Aberystwyth road and took minor roads via Devil's Bridge to Pontrhydfendigaid and Tregaron. I had been that way before without seeing much, but this time it was a real hot summer's day, with blue sky and fantastic visibility.
This is part of Wales's empty quarter, with a rolling -- almost prairie - like -- landscape of broad river valleys, wide depressions with lakes in them, and hilly areas with gentle slopes. This is the core of the Cambrian Mountains and the main watershed of Wales, with some streams flowing west and others flowing east -- but no glaciated troughs. During the big glacial episodes this area has been at the heart of the Welsh ice cap -- so there has been very thick ice sitting on this landscape -- but it has done virtually nothing in terms of landscape modification. The ice has been effectively stagnant, and probably cold-based, maybe with occasional aerial scouring but no streaming. The whole landscape reminded me of parts of the basalt plateaux of NW Iceland, except that here there are the remnants of a very old fluvial landscape which has been largely unmodified for millions of years.
Must try to get back there soon, so that I can take a more careful look.......
The Cambrian Mountains of mid-Wales, between Aberystwyth and Newtown. The undulating "watershed plateau" is clearly seen in the centre of the map. The brown-coloured area is the highest part of the plateau, around Pumlumon.
Typical landscape on the plateau
Extract from the BGS glacial map of Wales, showing Devensian ice movements at the centre of the Welsh Ice Cap. Note the outlet glaciers flowing away from the ice-shed area -- the Rheidol and Ystwyth Glaciers flowing west, and the Wye and Severn Glaciers flowing NE and SE respectively.
Friday, 1 June 2018
Herbert Thomas scrutinized
(As we all know, I don't agree with the authors that they have definitively identified the locations from which some of the bluestones and the debitage at Stonehenge have come -- the best that can be said is that they have narrowed things down to the most likely neighbourhoods.)
==================
Retracing the footsteps of H.H. Thomas: a review of his Stonehenge bluestone provenancing study
Richard Bevins and Rob Ixer
Antiquity, May 2018.
Published online: 31 May 2018
Abstract
The long-distance transport of the Stonehenge bluestones from the Mynydd Preseli area of north Pembrokeshire was first proposed by geologist H.H. Thomas in 1923. For over 80 years, his work on the provenancing of the Stonehenge bluestones from locations in Mynydd Preseli in south Wales has been accepted at face value. New analytical techniques, alongside transmitted and reflected light microscopy, have recently prompted renewed scrutiny of Thomas's work. While respectable for its time, the results of these new analyses, combined with a thorough checking of the archived samples consulted by Thomas, reveal that key locations long believed to be sources for the Stonehenge bluestones can be discounted in favour of newly identified locations at Craig-Rhos-y-felin and Carn Goedog.
Abstract
The long-distance transport of the Stonehenge bluestones from the Mynydd Preseli area of north Pembrokeshire was first proposed by geologist H.H. Thomas in 1923. For over 80 years, his work on the provenancing of the Stonehenge bluestones from locations in Mynydd Preseli in south Wales has been accepted at face value. New analytical techniques, alongside transmitted and reflected light microscopy, have recently prompted renewed scrutiny of Thomas's work. While respectable for its time, the results of these new analyses, combined with a thorough checking of the archived samples consulted by Thomas, reveal that key locations long believed to be sources for the Stonehenge bluestones can be discounted in favour of newly identified locations at Craig-Rhos-y-felin and Carn Goedog.
REFERENCES
- Bevins, R.E. & Ixer, R.A.. 2013. Carn Alw as a source of the rhyolitic component of the Stonehenge bluestones: a critical re-appraisal of the petrographical account of H.H. Thomas. Journal of Archaeological Science 40: 3293–301. https://doi.org/10.1016/j.jas.2013.03.017CrossRef | Google Scholar
Bevins, R.E., Lees, G.J. & Roach, R.A.. 1989. Ordovician intrusions of the Strumble Head-Mynydd Preseli region, Wales: lateral extensions of the Fishguard Volcanic Complex. Journal of the Geological Society of London 146: 113–23. https://doi.org/10.1144/gsjgs.146.1.0113CrossRef | Google Scholar
Bevins, R.E., Pearce, N.J.G. & Ixer, R.A.. 2011. Stonehenge rhyolitic bluestone sources and the application of zircon chemistry as a new tool for provenancing rhyolitic lithics. Journal of Archaeological Science 38: 605–22. https://doi.org/10.1016/j.jas.2010.10.014CrossRef | Google Scholar
Bevins, R.E., Ixer, R.A., Webb, P.C. & Watson, J.S.. 2012. Provenancing the rhyolitic and dacitic components of the Stonehenge Landscape bluestone lithology: new petrographical and geochemical evidence. Journal of Archaeological Science 39: 1005–19. https://doi.org/10.1016/j.jas.2011.11.020CrossRef | Google Scholar
Bevins, R.E., Ixer, R.A. & Pearce, N.J.G.. 2014. Carn Goedog is the likely major source of Stonehenge doleritic bluestones: evidence based on compatible element discrimination and principal component analysis. Journal of Archaeological Science 42: 179–93. https://doi.org/10.1016/j.jas.2013.11.009CrossRef | Google Scholar
Bevins, R.E., Atkinson, N., Ixer, R.A. & Evans, J.A.. 2017. U-Pb zircon age constraints for the Fishguard Volcanic Group and further evidence for the provenance of the Stonehenge bluestones. Journal of the Geological Society of London 174: 14–17. https://doi.org/10.1144/jgs2016-042CrossRef | Google Scholar
Cunnington, W. 1884. Stonehenge notes: the fragments. Wiltshire Archaeological and Natural History Magazine 21: 141–49.Google Scholar
Darvill, T. & Wainwright, G.. 2014. Beyond Stonehenge: Carn Menyn quarry and the origin and date of bluestone extraction in the Preseli Hills of south-west Wales. Antiquity 88: 1099–114. https://doi.org/10.1017/S0003598X00115340CrossRef | Google Scholar
Darvill, T. & Wainwright, G.. 2016. Neolithic and Bronze Age Pembrokeshire, in James, H., John, M., Murphy, K. & Wainwright, G.(ed.) Pembrokeshire county history, volume 1, prehistoric, Roman and early medieval Pembrokeshire: 222–55. Haverfordwest: Pembrokeshire County History Trust.Google Scholar
Geological Survey of the United Kingdom. 1902. Summary of Progress of the Geological Survey of the United Kingdom and Museum of Practical Geology for 1901. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1903. Summary of Progress of the Geological Survey of the United Kingdom and Museum of Practical Geology for 1902. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1904. Summary of Progress of the Geological Survey of the United Kingdom and Museum of Practical Geology for 1903. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1905. Summary of Progress of the Geological Survey of the United Kingdom and Museum of Practical Geology for 1904. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1906. Summary of Progress of the Geological Survey of the United Kingdom and Museum of Practical Geology for 1905. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1907. Summary of Progress of the Geological Survey of Great Britain and Museum of Practical Geology for 1906. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1908. Summary of Progress of the Geological Survey of Great Britain and Museum of Practical Geology for 1907. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1909. Summary of Progress of the Geological Survey of Great Britain and Museum of Practical Geology for 1908. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1910. Summary of Progress of the Geological Survey of Great Britain and Museum of Practical Geology for 1909. London: HMSO.Google Scholar
Geological Survey of the United Kingdom. 1921. Summary of Progress of the Geological Survey of Great Britain and Museum of Practical Geology for 1920. London: HMSO.Google Scholar
Harrison, R.K., Sanderson, B.W. & Hart, M.J.. 1979. Petrographical report: excavated rock fragments from Stonehenge and Silbury Hill. Institute of Geological Sciences Technical Report WG/PE/79/150.Google Scholar
Hawley, W. 1921. Stonehenge: interim report on the excavation. The Antiquaries Journal 1: 19–39. https://doi.org/10.1017/S0003581500052975CrossRef | Google Scholar
Ixer, R.A. & Bevins, R.E.. 2010. The petrography, affinity and provenance of lithics from the Cursus Field, Stonehenge. Wiltshire Archaeological & Natural History Magazine 103: 1–15.Google Scholar
Ixer, R.A. & Bevins, R.E.. 2011a. Craig Rhos-y-felin, Pont Saeson is the dominant source of the Stonehenge rhyolitic debitage. Archaeology in Wales 50: 21–31.Google Scholar
Ixer, R.A. & Bevins, R.E.. 2011b. The detailed petrography of six orthostats from the Bluestone Circle, Stonehenge. Wiltshire Archaeological & Natural History Magazine 104: 1–14.Google Scholar
Ixer, R.A. & Bevins, R.E.. 2013. Chips off the old block: the Stonehenge debitage dilemma. Archaeology in Wales 52: 11–22.Google Scholar
Ixer, R.A. & Bevins, R.E.. 2016. Volcanic Group A debitage: its description and distribution within the Stonehenge Landscape. Wiltshire Archaeological & Natural History Magazine 109: 1–14.Google Scholar
Ixer, R.A., Bevins, R.E. & Gize, A.P.. 2015. Hard ‘volcanics with sub-planar texture’ in the Stonehenge Landscape. Wiltshire Archaeological & Natural History Magazine 108: 1–14.Google Scholar
Ixer, R.A., Turner, P., Molyneux, S. & Bevins, R.E.. 2017. The petrography, geological age and distribution of the Lower Palaeozoic sandstone debitage from the Stonehenge Landscape. Wiltshire Archaeological & Natural History Magazine 110: 1–16.Google Scholar
John, B., Ellis-Gruffydd, D. & Downes, J.. 2015. Quaternary events at Craig Rhosyfelin, Pembrokeshire. Quaternary Newsletter 137: 16–32.Google Scholar
Jones, O.T. 1966. Cerrig Llwydion Carn Meini. Y Gwyddonydd 4: 215–20.Google Scholar
Maskelyne, N.S. 1878. Stonehenge: the petrology of its stones. Wiltshire Archaeological and Natural History Magazine 17: 147–60.Google Scholar
Parker Pearson, M. 2015. Stonehenge: making sense of a prehistoric mystery. York: Council for British Archaeology.Google Scholar
Parker Pearson, M. 2016a. The sarsen stones of Stonehenge. Proceedings of the Geologists’ Association 127: 363–69.CrossRef | Google Scholar
Parker Pearson, M. 2016b. Secondhand Stonehenge? Welsh origins of a Wiltshire monument. Current Archaeology 311: 18–22.Google Scholar
Pearson, Parker, M., Bevins, R.E., Ixer, R.A., Pollard, J., Richards, C., Welham, K., Chan, B., Edinborough, K., Hamilton, D., Mcphail, R., Schlee, D., Schwenninger, J.-L., Simmons, E. & Smith, M.. 2015. Craig Rhos-y-felin: a Welsh bluestone megalith quarry for Stonehenge. Antiquity 89: 1331–52. https://doi.org/10.15184/aqy.2015.177CrossRef | Google Scholar
Parker Pearson, M., Bevins, R.E., Ixer, R.A., Pollard, J., Richards, C. & Welham, K.. In press. Long-distance landscapes: from quarries to monument at Stonehenge, in Mataloto, R. (ed.) Megaliths and geology: proceedings of a conference in memory of Rui Boaventura. Redondo: Centro Cultural do Redondo.Google Scholar
Parkinson, J. 1897. Some igneous rocks in north Pembrokeshire. Quarterly Journal of the Geological Society of London 53: 465–76. https://doi.org/10.1144/GSL.JGS.1897.053.01-04.37CrossRef | Google Scholar
Part, G.M. 1922. Notes on the Ordovician lavas of Mynydd Prescelly, north Pembrokeshire. Geological Magazine 54: 310–23. https://doi.org/10.1017/S0016756800109884CrossRef | Google Scholar
Teall, J.J.H. 1894. Notes of sections of Stonehenge rocks belonging to Mr W. Cunnington. Wiltshire Archaeological and Natural History Magazine 27: 66–68.Google Scholar
Thomas, H.H. 1923. The source of the stones of Stonehenge. The Antiquaries Journal 3: 239–60. https://doi.org/10.1017/S0003581500005096CrossRef | Google Scholar
Thorpe, R.S., Williams-Thorpe, O., Jenkins, D.G. & Watson, J.S., with contributions by Ixer, R.A. & Thomas, R.G.. 1991. The geological sources and transport of the bluestones of Stonehenge, Wiltshire, UK. Proceedings of the Prehistoric Society 57: 103–57.CrossRef | Google Scholar