Some of the ideas discussed in this blog are published in my new book called "The Stonehenge Bluestones" -- available by post and through good bookshops everywhere. Bad bookshops might not have it....
To order, click

Monday 28 December 2015

Bayvil Farm gatepost

Bayvil Farm is located about 2 km from Nevern, just on the north side of the Nevern-Glanrhyd Road.  This stone -- one of a pair at the farm entrance -- is around 2m tall above the ground surface, and maybe 3m long in total.  It's made of quite distinctive spotted dolerite, with large and widely separated creamy white spots.  The other stone is smaller, and is made of unspotted dolerite. 

This stone is very irregular in shape, and it has lost a big chunk off its flank and has suffered a lot of other damage as well -- some of it associated with the drilling of three holes.  But it is of course basically a pillar.

This is a rather mysterious stone, because the top two holes are too high up to be of any use for hanging a gate, and are not aligned on the same vertical line.  The lowest hole is even more of an enigma, since it is drilled through the stone in quite a different direction.

There is a good weathering crust on this stone, and so it might be a glacial erratic.  But I have my doubts about that, given that this is about 8 km north of Carn Goedog or Cerrig Marchogion -- the two most likely source outcrops for this particular pillar.  It is most likely to have been taken from one or other of these localities in the 1800's ...........with a surface that was already well weathered.   Or could it have been previously used as a standing stone somewhere near its present position?  These "northern" gateposts are more and more intriguing......

Wednesday 23 December 2015

Supplementary Info also now on Academia

For those who were having problems accessing the recent "Archaeology in Wales" paper and its supplementary information, I have now placed both the paper and the photo gallery onto Academia as well.  Here is the link to the photos:

These photos will give a clearer picture as to why we think there are no human traces at all in the 16 or more so-called "engineering features" in and around the Craig Rhosyfelin dig.  Nothing we have seen in the literature (or in the media) since we wrote the "Archaeology in Wales" paper has done anything to ameliorate our position.

Anomalies, Aberrations and Anachronisms

It seems to me that the main grounds for assuming that the "big rhyolite block" at Rhosyfelin is a "proto-orthostat" put into position by heroic quarrymen are that it is an anomaly, or an aberration or an anachronism. Its position is supposed to be peculiar, as is its size, its shape and its flat upper surface..... and the assumption is that because the archaeologists are amazed by it, it cannot possibly be a perfectly normal block of rock in a perfectly natural position.  Hmmm.....

Let's celebrate Christmas by looking at a few of nature's aberrations.  We wonder at them because they are unusual or even peculiar, and such features appear all the time in photo galleries on the web that are devoted to "amazing natural wonders" and so forth.  But actually they look as they do because of the operation of the laws of physics, and every time, when geomorphologists and geologists do a little work on them, they become rather less miraculous and a little more mundane.  Boring, I know......  but they are still spectacular and exciting to geomorphologists, and it was features such as these that encouraged me into an academic career all those years ago.  Enjoy!

And remember that many of these features have signs of human habitation close by -- and as far as I know nobody -- except those of the Von Daniken school of science -- is inclined to say that they were created by our superhuman ancestors or by aliens from outer space......

Tuesday 22 December 2015

Bear Islands, Scoresby Sund, East Greenland

This is nothing to do with Stonehenge, but everything to do with glacial geomorphology.  A fabulous image of part of the Bear Islands archipelago, in Hall Bredning, where several large outlet glaciers have converged and expanded from their spectacular troughs out into the vast open spaces of Scoresby Sund.  I could give a whole glacial geomorphology lecture about this one photo, but not now, since the sauna is ready, the hour is late,  and it's time for a good sweat........

Rhosyfelin papers now on Academia

I was sad to hear that not everybody can get at papers on Researchgate.  So I have put our two published papers on Academia too.  Here are the hyperlinks:

If anybody has any problems getting at them, let me know.

Rhosyfelin RIGS designation is confirmed

This is the RIGS citation for the site, which has now been formally designated. The process has taken well over a year, and it is certain that there has been heavy political pressure behind the scenes to prevent the designation from happening at all, or to replace it with something more in line with what the archaeologists and the National Park would like to see. Part of the problem is that there is no RIGS committee for West Wales, with decisions on designation now being taken at an all-Wales level, by a new body called Geoconservation Wales. That means that the "local knowledge" component has been lost. So there was an argument that this should be designated as a "dual" (geomorphological / archaeological) site. We stuck to our guns on this and argued that there is a separate system for designating archaeological and heritage sites, and that if the archaeologists want to go down that route, that's fine by us. We have made the citation less confusing by dropping a long para on the geological context and by concentrating on the Quaternary. We have also agreed the incorporation of a statement explaining that there is a disagreement between geomorphologists and archaeologists as to what the significance of this site really is!

Much ado about not very much, and thanks to John Downes for doing all the hard work. In any case, the citation is not set in stone, and can easily be modified in the future if new discoveries are made. But this is a designation with planning weight, which means a degree of protection for Rhosyfelin from future development.

Site Name: Rhosyfelin

RIGS (Regionally Important Geodiversity Sites) Number: 564
Grid Reference: SN117362


RIGS Statement of Interest:

Craig Rhosyfelin is a craggy outcrop of Ordovician rhyolite in the valley of the Afon Brynberian. The rhyolite belongs to the Fishguard Volcanic Group which outcrops along the northern margin of Mynydd Preseli. This site is of particular interest since the rocks are exposed on a series of fracture planes and rhyolite samples from the rock face have recently been matched to “bluestone” fragments in the "debitage" at Stonehenge (See also Carn Menyn RIGS 555). Rhosyfelin is also significant in that it offers an opportunity to examine some of the geomorphological processes and landforms typical of the Pleistocene period in the area. There are examples of scoured surfaces, frost shattered crags and scree, glacial till, fluvioglacial gravels and solifluction deposits. With regard to the rock face, from a geomorphological perspective there is ample evidence that glacial, periglacial and biological processes have all contributed to the widening of joints and the accumulation of rock debris at the foot of the Rhosyfelin crag.


Recent archaeological excavations (Parker Pearson et al, 2015), however, have led to the assertion that part of the Craig Rhosyfelin outcrop and some of the stone debris at its base (including a large, roughly rectangular block) are the result of prehistoric quarrying. This suggestion has been strongly refuted by the current authors (John, Elis-Gruffydd & Downes, 2015a, 2015b) who have argued that the features of the site constitute an association of natural geomorphological landforms and Quaternary sediments. Continued research at the site, both geomorphological and archaeological, including the possible application of Terrestrial Cosmogenic Nuclide (surface exposure) dating, may help resolve the relative contributions of natural and anthropogenic processes at the site.

Geological setting:

The rhyolitic crags at Rhosyfelin in the Brynberian valley appear to be an erosional remnant of the main outcrop of the Fishguard Volcanic Group as mapped by the BGS on the 1:50,000 map ( Sheet 210 Fishguard). These rhyolitic lavas are Mid Ordovician in age (Llanvirn stage). They dip steeply northwards (75º according to the BGS) on the north flank of Mynydd Preseli. Field observations at Rhosyfelin reveal deep almost vertical fractures with numerous horizontal cross fractures. The rhyolite is a splintery dark blue rock which weathers to a light grey colour. A considerable amount of rock debris, accumulated at the foot of the steep rock face, has been uncovered during a recent dig by archaeologists.

The geomorphological history of Rhosyfelin is complex since the site has been overridden by the ice of the Irish Sea Glacier on at least two occasions during the last half million years. As on many of the other tors and crags in the area, there are signs of substantial ice smoothing and block removal; it is likely that Craig Rhosyfelin was once higher and more prominent than it is today. Glacial erratics from the north have also been transported into the locality (John, Elis-Gruffydd and Downes, 2015a, 2015b).

Fluvioglacial erosion has occurred at the site on a substantial scale. The main Brynberian river valley is steep sided and has clearly carried great volumes of meltwater. Subglacial meltwater flow is suggested by the small steep channel adjacent to the exposed rock face. It is possible that meltwater has flowed up and over a col under hydrostatic pressure before descending to join the main discharge route again at the end of the rocky spur. It is likely that these features are inherited from the Anglian glacial episode.

Apart from the broken rockfall debris and scree that has accumulated beneath the rock face on a smoothed and undulating bedrock surface, there is an extensive exposure of Devensian glacial till containing many boulders and smaller clasts of dolerite and other erratics. This has been exposed during the archaeological dig. Near the end of the spur this till grades into a fluvioglacial deposit of gravels incorporating many dolerite boulders and other rounded stones. Both bedrock and detached rock slabs in this vicinity are heavily abraded. Recent excavations have exposed a clay-rich horizon beneath the fluvioglacial gravels that may represent a temporary pro-glacial lake on the floor of the valley. There are also periglacial and colluvial slope deposits up to 2m thick, with some internal variation, possibly representing climatic oscillations during the Holocene.

On the valley floor there is a well-developed flood plain where river gravels are currently being reworked during swings by the river. The process of crag diminution by rockfalls is ongoing, with biological processes (root expansion in joints and fissures) currently prominent.

Network context of the site:

Quaternary and Geomorphological RIGS in S.W. Wales are assigned to one or more of the following networks.

1. Pre-Quaternary landscape evolution.
2. Glacial Geomorphology. This network includes such landforms as moraines, cirques, protalus ramparts and kettleholes, and deposits composed of till, moraine and scree, for example.
3. Periglacial Geomorphology. Sub-networks are landforms and deposits formed in environments around the fringes of glacial terrains. They include pingos, patterned ground, ice wedges and solifluction features.
4. Fluvio-glacial Geomorphology. Sub-networks are landforms that include alluvial fans, patterned ground and meltwater channels, together with their associated deposits.
5. Fluvial Geomorphology. Landforms are terraces, meanders, bars, waterfalls, gorges and palaeochannels, for example, which are associated with a variety of deposits.
6. Holocene Geomorphology. The landforms include raised bogs and screes, whilst the deposits comprise peat and gravel, for example.
7. Coastal Geomorphology. Landforms are diverse, comprising spits, dune fields, beaches and cusps, among several others. Associated deposits include dune sands and shingle.
8. Karst.

This RIGS illustrates Glacial Geomorphology including such deposits as glacial till and ice scoured surfaces (Net 2) Periglacial Geomorphological features such as solifluction deposits (head) and scree (Net. 3). Features of Fluvioglacial Geomorphology (Net. 4) include meltwater channels and possible lacustrine deposits.


Potential use (general):

Although the geomorphology of the area is highly specialised, the significance of the rocks as a possible source of some of the rhyolitic fragments at Stonehenge suggests that a public awareness initiative may be appropriate.

Potential use (educational):

The rocks are of interest to geologists studying the Lower Palaeozoic igneous rocks of SW Wales, to geomorphologists studying the effects of Pleistocene glacial episodes on the flanks of Preseli, and also to archaeologists interested in the origin of some of the rhyolitic debris at Stonehenge.

Other comments:

The archaeological dig site has now been infilled and the site is accessible via a public footpath.


BRITISH GEOLOGICAL SURVEY (2010). 1:50,000 Geological Sheet 210, Fishguard, NERC.

BURT,C.E., et al. (2012) Geology of the Fishguard district. A brief explanation of the geological map Sheet 210 Fishguard, NERC

CAMPBELL, S. & BOWEN, D.Q. (1989). Quaternary of Wales, Geological Conservation Review Series, No. 2, Nature Conservancy Council, Peterborough.

CATT, J.A., GIBBARD, P.L., LOWE, J.J., McCARROLL, D., SCOURCE, J.D., WALKER, M.J.C. & WYMER, J.J. (2006). Quaternary: ice sheets and their legacy. In BRENCHLEY, P.I. & RAWSON, P.E. (eds) The Geology of England & Wales, The Geological Society, London. 430-467.

HAMBREY, M.J., DAVIES, J.R., GLASSIER, N.F., WATERS, R.A., DOWDESWELL, J.A., WILBY, P.R., WILSON, D. & ETTIENNE, J.L.(2001). Late Devensian glacigenic sedimentation and landscape evolution in the Cardigan area of South West Wales. Journal of Quaternary Science. 16, 455-482.

HUNTER, A. (2001). The Geological History of the British Isles. SXR260. Open University, Milton Keynes.112-123

IXER, R.A. and BEVINS, R.E. (2011). Craig Rhos-Y-Felin, Pont Saeson is the dominant source of the Stonehenge rhyolitic ‘debitage’. Archaeology in Wales 50, 21–31

IXER, R. A. and BEVINS, R, E. (2014). The Vexed Question of the Stonehenge Stones. British Archaeology, Sept-Oct 2014, 50-55

IXER, R.A and BEVINS, R.E (2013). Chips off the old block: the Stonehenge debitage dilemma. Archaeology in Wales 52, 11-22.

JOHN, B.S. (1970). Pembrokeshire. In LEWIS, C.A. (ed.) The Glaciations of Wales and adjoining regions. Longman, London. 229-265.

JOHN, B.S. (1973). Vistulian Periglacial Phenomena in South-West Wales, Biuletun Peryglacjalny 22, 185-212.

JOHN, B.S. (2008) The Bluestone Enigma. Greencroft Books, Newport, Pembrokeshire, 160 pp.

JOHN,B,S. (2013) A Long History of Rhosyfelin.

JOHN, B.S, ELIS-GRUFFYDD, D &  DOWNES, J (2015a). "Quaternary Events at Craig Rhosyfelin, Pembrokeshire." Quaternary Newsletter, October 2015. No 137, pp 16-32.

JOHN, B.S., ELIS-GRUFFYDD, D & DOWNES, J (2015b). Observations on the supposed ‘Neolithic Bluestone Quarry’ at Craig Rhosyfelin, Pembrokeshire. Archaeology in Wales 54, pp 139-148.

McCARROLL, D. (2001). The glacial geomorphology of West Wales. In WALKER, M.J.C. & McCARROLL, D. The Quaternary of West Wales: Field Guide. Quaternary Research Association, London, 9-16.

PARKER-PEARSON, M., BEVINS, R, E., IXER, R. A.; POLLARD, J.; RICHARDS, C.; WELHAM, K.; CHAN, B.; EDINBOROUGH, K.; HAMILTON, D.; MACPHAIL, R.; SCHLEE, D.; SCHWENNINGER, J.; SIMMONS, E. & SMITH, M. (2015). Craig Rhos-y-felin: a Welsh bluestone megalith quarry for Stonehenge. Antiquity, 89 (348) Dec 2015, pp 1331-1352

THORPE, R.S., WILLIAMS-THORPE, O., JENKINS, D.G. & WATSON, J.S. (1991) The geological sources and transport of the bluestones of Stonehenge, Wiltshire, UK. Proceedings of the Prehistoric Society, 57, 103-157.


A old friend of mine, Ian Evans, who keeps an eye on such things, has spotted this on Researchgate:

"With 440 new reads, Brian John was the most read author from Durham University last week."

I think that's quite wonderful, given that I left Durham University almost 40 years ago in order to enjoy a quiet life in the country........

PS.  When you sign up on Researchgate you have to give your present or past academic affiliation.

Sunday 20 December 2015

Breaking News: Stonehenge bluestones came from a Neolithic Temple at Bedd yr Afanc

Gentle reader, if you are a betting person, here is a racing certainty for you.  Put a quid or two down on it, and you can't lose........... 

In 2016 it will be announced to the world that the bluestones at Stonehenge were transported there from a large passage grave, tomb or "temple of the ancestors" located at Bedd yr Afanc, on the moorland near Brynberian.  The site is located very conveniently between Rhosyfelin and Carn Goedog, and you can read a lot more about it by typing in "Bedd yr Afanc" into the blog search box.  Everybody knows that there is a rather unusual passage grave there -- just a small cluster of unspectacular stones in two parallel rows.  But the question is this:  what was there before it was destroyed?  Something like this?

The reconstructed (and somewhat elaborated?) mound at Newgrange in Ireland, within which is a passage grave. The facade is faced with quartz cobbles brought in from the surrounding countryside.

The Setup

In the writing trade, this is what is meant by a setup: presenting the elements that flesh out the story and lay the groundwork for the plot. They are conveyed by the writer in a way that establishes a character, world, or situation, while moving the plot and story forward at the same time.

This is perfectly relevant here, since this is all about storytelling....... and since, after five years of digging and storytelling, we are moving towards a climax.

The storytellers are already hard at work, laying out their clues. One quote from the latest article by MPP and his colleagues in "British Archaeology": "Somewhere, on the land between the bluestone quarries, we think there is a passage tomb, formerly built of bluestones, waiting to be investigated. Could this have been a tomb for the ancestors that was dismantled and moved to Salisbury Plain, the tangible history of a Welsh neolithic tribe carried to their new homeland in one of the most extraordinary journeys of prehistoric times? Only time will tell."

Another quote from the recent press release that accompanied the publication of the "Antiquity" article:  "Prof Kate Welham, of Bournemouth University, said the ruins of a dismantled monument were likely to lie between the two megalith quarries. “We’ve been conducting geophysical surveys, trial excavations and aerial photographic analysis throughout the area and we think we have the most likely spot. The results are very promising. We may find something big in 2016,” she said."

At the end of the "Antiquity" article:  "Might the bluestones have formed one or more monuments within Wales that were dismantled and moved in order to be incorporated, eventually, into Stonehenge? Such an act could have served to merge two sacred centres into one, to unify two politically separate regions, or to legitimise the ancestral identity of migrants moving from one region to another. Future research into Neolithic monuments within north Pembrokeshire may shed light on these possibilities." Note the the talk is no longer of an ancient stone circle, but of a "monument" which could well be taken to mean a passage grave site or tomb.

Again, about the imagined Carn Goedog "engineering features" in the Brit Arch article:  "Beyond the ditch we found a platform of redeposited soil that formed a 5m-long ramp leading away from the quarry and curling northwards down the slope towards the valley in which Craig Rhos-y-felin sits......"  Note the suggestion that stones were taken northwards and downhill -- ie towards Bedd yr Afanc.


The Dream Location 

We have already discussed Bedd yr Afanc on this blog, and Chris, Hugh and others have been pondering on its choice as the next big location for the travelling circus.  And it is indeed the dream location.  It's on a dry expanse of relatively flat land with ample space for a large structure -- and surrounded by land that is more water-logged.  It's in the right place, more or less equidistant between Rhosyfelin and Carn Goedog.  There is a very substantial trackway across the moor, and if you like you can see it as connecting Carn Goedog and Bedd yr Afanc.  Although the stones of the passage grave remnants are not very large, they are varied in lithology, and seem to include dolerites and rhyolites and at least one stone that might be a gabbro.  No doubt the geologists will already be hard at work sorting out provenances.......

And then we come to the quartz cobbles that are needed in order to promote the view that Bedd yr Afanc was at one time equal in magnificence to Newgrange.  Take a look at this post:

and this one:

 But bits of quartz are of minor significance compared to the mythological value of Bedd yr Afanc.  The local story of the Afanc is one of the most famous in Welsh folklore, involving a very nasty water monster and a fair maiden, as set out here:

It's a great story, and if we like we can built into it all sorts of meanings and all sorts of associations with folk memories of Bedd yr Afanc as a sacred or revered site, involving heroism, sacrifice, death and burial.  So the passage grave is the place where the monster was buried -- and because of its mystical and religious associations it's not a great leap from there to creating a narrative which will justify its use as a "site of the ancestors" -- later to be dismantled and transported off to Stonehenge.

The possibilities are endless.  As we speak, Bedd yr Afanc is probably being prepared for stardom and is being lifted to the top of the National Park's wonderful heritage site list.    You can see Bedd yr Afanc from the new Visitor Centre, just up on the hillside:

Leaflets, guided tours, cups of tea, rolling Powerpoint presentations and videos, Welsh cakes, exhibitions of photos, jewellery made out of "monster rock" fragments -- once the Visitor Centre is completed, there is no knowing where it will all lead.  How about cuddly afanc monster toys?  Pots of pickled onions and bilberry jam marketed under the "Afanc" label.........

And anything they can do at Newgrange, we can do in Pembrokeshire.  Will a Lottery grant cover the cost, I wonder?

Excuse me -- I'm getting carried away.  But remember, folks, that you read it here first.  Put your money on it!  It's a racing certainty........

Saturday 19 December 2015

The new BritArch article by MPP et al

Here is the citation for the new article in BA:

Parker Pearson, M., Pollard, J., Richards, C., Schlee, D., and Welham, K. (2016).  "In search of the Stonehenge Quarries,"  British Archaeology Jan/Feb 2016, pp 16-23.

Sadly, it's behind a paywall, so you can only read it if you are a BA subscriber. 
I've been taking a look at it, and it is undoubtedly beautifully illustrated and designed, with a raft of splendid annotated photographs.  But there is nothing new in it, and as ever the problem is that the edifice is founded on the assumptions that (a) the bluestones must have been quarried in the places pointed out by geologists Richard Bevins and Rob Ixer, and (b) the human transport hypothesis has been established as fact.  So yet again, we have ruling hypotheses and bad science.  In the very first paragraph, we know what is coming: "The Welsh ‘bluestones’ stand no taller than 2.6m and are dwarfed by the sarsens that make up Stonehenge’s outer circle and inner horseshoe of trilithons. But moving these 1-2 tonne monoliths 180 miles across neolithic countryside must rank as one of the greatest achievements in human prehistory........."

Why, oh why, can we not have something scholarly, even in a popular journal?  Is it too much to ask that if the authors of articles want us to believe their stories, they should at least give us their evidence first and then at the end invite us to accept their interpretation of it?  But there seems to be a weird belief that if you tell your story with sufficient panache, and with some nice pictures to accompany it, it is bound to be true.......  and I'll continue my gripe by bemoaning the fact that editors like Mike Pitts apparently go along with this way of communicating with the world.

Popular articles of this type are OK if they follow hard on the heels of detailed peer-reviewed research reports in which all the evidence from a dig is clearly laid out and analysed.  But here we have no prior research report, and we are simply asked to accept everything on trust........

Craig Rhosyfelin

And the contents of the paper? The first section simply summarises the earlier published work of Ixer and Bevins, flagging up the similarities between some of the rhyolite fragments in that famous JF Stone shoe-box and the foliated rhyolites at Rhosyfelin.  Then we get onto the narrative of the dig.  As soon as the 4m-long monolith is mentioned, quarries and quarrymen come into the frame, as does the "prehistoric surface" lying beneath medieval, iron age and bronze age "archaeological layers".  They mention the "monolith extraction point" and the "shallow groove" and "primitive hole" supposedly used with wedges to prise  a monolith off the rock face.  Then they go on to talk about the "orthostat pivot",  the "stone jetty-like structure built out from the bank of a prehistoric stream bed",  a "flat-bottomed hollow way" and an "artificial terrace of stones"  -- all assumed to have been connected with quarrying operations.  As with the "Antiquity" article, there is no description of the stratigraphy.

Parker Pearson and his colleagues reveal some of their radiocarbon dates, stating that the "hillwash" or colluvial layer is from around 1030-890 BC and that organic material from beneath the "proto-orthostat" dates from 2140-1950 BC.  This means that the monolith cannot have come into its present position before the Early Bronze Age.  That must have been a profound disappointment to the archaeologists, since a Neolithic date was needed to tie the stone into the supposed Neolithic monolith collecting expeditions supposed to have supplied the bluestones for Stonehenge.

In the Neolithic hearth near the rock face (with which we have no problem), material has been dated to 3620-3129 BC, three or four hundred years earlier than the first stage of Stonehenge.  It is suggested that one monolith at Stonehenge came from here, and that stump 32d in the bluestone circle might be all that is left of it.

So nothing in the dating sequence is of any use for confirming the "Neolithic quarrying" scenario.  The hearth material is too early, and the emplacement of the rhyolite monolith is too late.   It looks as if the authors of this article are having to come to terms with the fact that there was a long history of occupation at this site, and not a concentrated burst of activity at the time when bluestone monoliths for Stonehenge were needed.  So now they seem to be suggesting that there was also a long history of stone extraction, beginning maybe 500 years before any stones were taken to Stonehenge.  They present no evidence in support of that contention.  But inevitably it leads later on to the idea of a proto-Stonehenge somewhere in the local area, for which the search will start in 2016...........

((The most interesting fact from this article is that a chip of foliated rhyolite assumed to be from Rhosyfelin has been found beneath the bank of the Stonehenge Avenue, dated to 2500-2270 BC.  Also Anthony Johnson refers in his book to "quantities of bluestone fragments within the bank rubble" -- that's rather interesting, given that the bank and ditch at Stonehenge are dated to c 3,000 BC.  He also says there has been "hardly any archaeological investigation of the bank", although we know it is made mostly of chalk rubble excavated from the ditch. So regardless of whether bluestones were set into the Aubrey Holes, bluestone material existed in the Stonehenge landscape at least 5,000 years ago.  This of course ties in with the occurrence of the Boles Barrow bluestone.))

Postscript:  What's coming into the frame here again is the DEBU (date of earliest bluestone use) at Stonehenge.    The DEBU must be around 5,000 years BP or even earlier.  Another reminder of what MPP has written previously:

Bluestones at Stonehenge

In 2008 we dug within Stonehenge itself, recovering 60 cremation burials from a pit, one of the circle of 56 Aubrey Holes that are concentric with the ditch and bank (see News, Nov/Dec 2008). These had originally been excavated by William Hawley in the 1920s when he dug 32 of the Aubrey Holes. Because the cremated bones were considered at that time to be of little scientific value, they were dumped in a mixed-up heap in Aubrey Hole 7 in 1935.

Our greatest discovery in that small hole, however, was that Hawley's workmen had not fully dug it out. In the bottom sat the undisturbed residue of a layer of chalk packing and a patch of crushed chalk caused by the weight of a standing stone. Checking Hawley's diary, we found that he had initially decided that the Aubrey Holes once contained small standing stones that were later pulled out. Sadly, Hawley did not have the courage of his convictions and, when confronted with the huge postholes of Woodhenge at Maud Cunnington's excavations in 1926–27, he changed his mind.

We realised that the small stones that once stood in the Aubrey Holes had to have been bluestones, the monoliths from the Preseli Hills and other parts of south Wales. By radiocarbon dating a cremation burial found in the chalk packing of Aubrey Hole 32, dug by Richard Atkinson in 1950, we had evidence that this stone circle was likely to have been put up around the time that the ditch and bank were dug in 3015–2935BC. This and other radiocarbon dates at Stonehenge have been refined by Bayesian statistical modelling of its stratigraphic sequence.

This meant the conventional threefold scheme of Stonehenge as an earthen monument, succeeded first by wooden posts and then by stone uprights could not be correct. Stonehenge was a stone monument from the beginning, and five of our new radiocarbon dates on cremated and unburnt human bone showed that it had also been a place of burial from this moment until at least 2400BC (statistically modelled as 2470–2300BC) – certainly during the erection of megaliths, and probably after as well.


The next part of the BritArch article deals with Carn Goedog -- the first time that the evidence from that site has been presented in a journal.  I'll take a look at that in another post.

The Rhosyfelin Affair: after the famine, the feast

Following the 2011 discovery by geologists Richard Bevins and Rob Ixer that some of the rhyolitic debris at Stonehenge could be provenanced to the Pont Saeson - Rhosyfelin area in Pembrokeshire, there have been five archaeological digs at a pre-selected "Neolithic quarry site" accompanied by many rather spectacular announcements as to the site's significance.

A big team has been at work at Rhosyfelin, assisted by a very large budget (the size of which has not been revealed).  Considerable technical resources have also been available, through the involvement of a number of UK universities and other institutions.   The world has been kept informed of progress through press announcements about a wondrous "proto-orthostat" uncovered at the site and about "the Pompeii of prehistoric quarries", and there have been countless lectures about the progress of the dig by Prof Mike Parker Pearson and his colleagues.  So there has not exactly been silence.  But strangely, there have been no publications at all, apart from brief mentions of the Rhosyfelin quarry and its significance in Parker Pearson's 2012 book and in a few articles of a general nature.  Archaeological journals and the media have publicized the "discoveries" sometimes in breathless terms, but there are no site descriptions on the record, no seasonal excavation reports and (until now) no peer-reviewed papers relating to five years of work.

If you are a cynic, you might explain this "failure to publish" as being down to the fact that nothing of any importance has been discovered, and that the archaeologists have been waiting, and waiting, and waiting for the discovery of the "smoking gun" that would sort out the Neolithic quarrying business once and for all.  There are also rumours of an embargo placed on publication by the National Geographic Society, which has a considerable financial stake in the archaeological dig.  Whatever the truth of the matter, it has done the reputations of the archaeologists no good at all to have waited five years before putting anything into print.

And after the famine, the feast.  In late 2015, within the space of a month, we have four papers in print, two from Mike Parker Pearson and his team, and two from Dyfed Elis-Gruffydd, John Downes and me:

Brian John, Dyfed Elis-Gruffydd and John Downes (2015). "Quaternary Events at Craig Rhosyfelin, Pembrokeshire." Quaternary Newsletter, October 2015 (No 137), pp 16-32.

Brian John, Dyfed Elis-Gruffydd and John Downes.  2015. OBSERVATIONS ON THE SUPPOSED “NEOLITHIC BLUESTONE QUARRY” AT CRAIG RHOSYFELIN, PEMBROKESHIRE".  Archaeology in Wales 54, pp 139-148. (Publication 14th December 2015)

Mike Parker Pearson, Richard Bevins, Rob Ixer, Joshua Pollard, Colin Richards, Kate Welham, Ben Chan, Kevan Edinborough, Derek Hamilton, Richard Macphail, Duncan Schlee, Jean-Luc Schwenninger, Ellen Simmons and Martin Smith (2015). Craig Rhos-y-felin: a Welsh bluestone megalith quarry for Stonehenge.   Antiquity, 89 (348) (Dec 2015), pp 1331-1352. 

Parker Pearson, M., Pollard, J., Richards, C., Schlee, D., and Welham, K. (2016).  "In search of the Stonehenge Quarries,"  British Archaeology,  Jan/Feb 2016, pp 16-23.

 There are interesting differences in the publication process used by the archaeologists and that of the earth scientists. Let's just outline these.

Tell, don't show

It must be obvious to any reader of the two archaeology papers that they are in effect extended confirmations of a ruling hypothesis.  Neither paper makes any pretence of following the normal protocols of scholarly publishing, and in each case, from the outset, we are told that Rhosyfelin is a Neolithic quarry -- and we are left in no doubt that the assertion is not even up for discussion.  So each paper goes on to describe the features of the "quarry" and to tell the reader how old they are and how they relate to one another.  I am intrigued about this -- not only because of the way in which the papers have been written but because the journal editors (Chris Scarre and Mike Pitts) have apparently gone along with this comprehensive sidestepping of scientific norms.  "Popular" articles with beautiful illustrations (and not too much boring detail) have taken the place of learned discourse.

And it gets worse.  Both of these papers are behind paywalls, so nobody except the subscribers to the two journals can read them.  So journalists, and members of the public have been unable to read the articles for themselves unless one or other of the authors has been kind enough to send them PDF copies.  At the same time there has been a massive publicity campaign involving all of the university media relations departments, with purple prose, quotes from the lead authors, photos and even video clips circulated to the world's media via the press agencies.  I've mentioned this media blitz in earlier blogs -- on the basis that there has been much marketing and not much substance.  But it has certainly been effective.  Journalists have accepted the press release contents at face value, and I suspect that hardly any of them have read or even scanned the papers themselves.  By now there must have been over 500 "Rhosyfelin quarry" stories in the world's media, and the little crag near Brynberian must be challenging Stonehenge on the global list of mythical locations...........

Show, don't tell

John, Dyfed and I are three retired academics who have no departmental resources behind us, no research funding and no commercial contracts to fulfill.  What we share is a good knowledge of Welsh geology and geomorphology and a long history of working in the field both as research scientists and as teachers working with students.

Our two papers, written earlier this year, arose from our concerns about the ongoing promotion of the Rhosyfelin quarrying hypothesis and the apparent determination of the digging team to refuse any geomorphological input into their work and to ignore any points which were deemed to be inconvenient.  During the digs, I arranged twice to meet with the archaeologists at Rhosyfelin, and on both occasions I was the only one who turned up.  So on both occasions I wandered about, made some notes, measured some things, took some photos, and then went home.  Points raised  at MPP lectures were dismissed out of hand,  and so a situation developed in which the diggers went their own sweet way while the rest of us undertook "guerrilla research."  Mostly this took place in the off season when the digging site was left open;  access has been very easy since Craig Rhosyfelin is immediately adjacent to a public footpath.

Based upon our "guerrilla research" we became increasingly convinced that everything at Rhosyfelin apart from the occupation traces could be explained by reference to natural processes, and that the quarrying hypothesis was deeply flawed.  We wrote two short notes, one for the Quaternary science community and the other aimed at archaeologists.  They were submitted in parallel to "Quaternary Newsletter" and to "Archaeology in Wales".  Both were peer reviewed and accepted after modifications, and we were gratified when both editors (Sven Lukas and Jemma Bezant) asked us to expand the papers and to incorporate more field evidence and illustrations.  (Editors don't often ask for papers to be lengthened!)  We were even more gratified when the AiW reviewer asked us to add a section on the end of our paper which directly addressed the archaeological issues, and when this request was supported by the editor.  So we added the section entitled "Supposed Human Activity Traces" which now seems to be attracting considerable attention from readers!

We are fully aware that our two papers are defective in many respects, and it is a cause for regret that we have not had access to resources that would have permitted accurate surveying, laboratory analyses of sediments, petrological studies of erratic clasts, palynological analyses of sediments or radiocarbon or OSL dating of the sediment sequence.  Given those constraints, we have sought to stick to scholarly norms by simply describing and interpreting what we have found at Rhosyfelin and by ignoring the related issues of bluestone transport and the building of Stonehenge.

We are grateful to both of the journal editors who have published our research for encouraging open access, and on this basis both papers were made available on publication day via Researchgate to anybody who is minded to look at them, to dissect them and -- if they want -- to criticise them.

In parallel, we have also put out press releases with a certain amount of purple prose in them, more or less at random, to assorted newsrooms and journalists -- without much expectation that they would be picked up just a week after the "Neolithic Quarry" story was widely reported.  We had no assistance whatsoever from the Reuters, Press Association or other press agencies.  But, amazingly, our story has been widely reported -- and maybe that is partly down to the fact the our papers have actually been looked at by journalists.

What next?

Feast?  It's felt a bit more like a feeding frenzy at times........ but Christmas is coming, and people will soon have other things on their minds.

We hope that this is not the end of research at Rhosyfelin.  The excavation pit is closed now, so most of the evidence cited by the archaeologists and by the Three Musketeers cannot be accessed.  But the big stone is still accessible, as are the rocky crags and the rock face, and new pits can always be opened for fresh investigations.  There are still many unanswered questions here, and we hope that other geomorphologists  will come in and contribute to the debate.

 As for the archaeologists, we have already suggested that in future they should try to describe what they see and not what they want to find, and that they should state their conclusions not at the beginning of their research but at the end.  To quote from our latest paper:

"Finally, it is a cause for regret that there has apparently been no geomorphological input into the fieldwork and assessment of the naturally-formed features and sediments at Rhosyfelin. It is recommended that in future there should be much greater cooperation between archaeologists and specialists from related disciplines. Also, it is suggested that great care should henceforth be exercised in the attempts by archaeologists to identify Neolithic quarries in the British landscape."

 And will the relevant parts of the archaeological community do any soul searching and take any lessons away from this little spat?  Time will tell.

 Couldn't resist this one!

Friday 18 December 2015

Thanks to the Archaeologists

I may not like the assumptions and the interpretations of the archaeologists who have been digging at Craig Rhosyfelin, but I do like the fact that we now have about 50 radiocarbon and OSL dates spread over a long history of intermittent occupation at the dig site.  That is a fantastic resource in its own right, and I suspect that in the long run the research of Prof MPP and his team will be remembered not because of quarries but because of what it tells us about settlement history and climate change in the area.

I'm still trying to unravel the stratigraphy as it is portrayed in the "Antiquity" paper, and to relate it to the stratigraphy as we observed it and as it is represented in our paper in "Archaeology in Wales."  All will become clearer in due course.  But it is already clear that the dates all come from the horizons which we refer to as "stratified slope deposits", colluvium and modern soil -- in some places these sediments are over 2m thick.  I really hope that the archaeologists have had some palynologists on board -- it will be fascinating to see what the pollen analyses tell us when they are published.

Some time needs to be spent on examining the contexts of those dated remains -- are there more papers on the way?


Brian John, Dyfed Elis-Gruffydd and John Downes.  2015. OBSERVATIONS ON THE SUPPOSED “NEOLITHIC BLUESTONE QUARRY” AT CRAIG RHOSYFELIN, PEMBROKESHIRE".  Archaeology in Wales 54, pp 139-148. (Publication 14th December 2015)

Mike Parker Pearson, Richard Bevins, Rob Ixer, Joshua Pollard, Colin Richards, Kate Welham, Ben Chan, Kevan Edinborough, Derek Hamilton, Richard Macphail, Duncan Schlee, Jean-Luc Schwenninger, Ellen Simmons and Martin Smith (2015). Craig Rhos-y-felin: a Welsh bluestone megalith quarry for Stonehenge.   Antiquity, 89 (348) (Dec 2015), pp 1331-1352. 

Rhosyfelin and Pengegin

Strange how things come together........  I was clearing out my study today, in preparation for the painter to move in after Christmas, when I happened upon this old OS 6" map which shows part of the Gwaun Valley (around Pontfaen) in great detail. It shows the Pengegin area, close to the small primary school that keeps open against all the odds.  A bit further to the west is Jabes Chapel and Bessie's famous pub, where MPP and all the archaeologists do their drinking when a big dig is going on..........   Maybe next time they are down here they can amble over with their shovels and do a little dig.

What we have at Pengegin is a very complex set of channels cut by glacial meltwater (probably during several phases) and now being modified further by river and slope processes.   The big valley is the Cwm Gwaun subglacial meltwater channel.  Here some of the meltwater has split from the main channel and has flowed through a subsidiary channel on the north side of the Pengegin rocky ridge.  This small channel is now followed by the road, and exits near the school.  Other chutes and channels have carried water in from the north.  I imagine that there must have been many rocky ridges like this within the main Gwaun Channel -- but most of them have been eaten away by the force of meltwater erosion -- attacked from both sides, as it were.

The Pengegin rock ridge is quite spectacular, and is about 10m high and 220m long.  It is tree covered today, as are the slopes of the channels to the north.

The rocky ridge is remarkably similar to that of Craig Rhosyfelin, and I would happily put a little bet down that if a dig was to take place on the northern flank of the ridge we would find not only a set of rockfall and other deposits very similar to those at Rhosyfelin, but also abundant traces of intermittent occupation by Mesolithic, Neolithic and later groups who were hunting and gathering in this rather beautiful valley.  The obvious place for their camp site would be on the northern flank of the ridge, where they would be well protected from the vagaries of the weather, summer or winter.  Note the earthwork and the homestead marked on the map, on the slope above the cottages.  They are lost in the woods, and I don't know anything about them.

Thursday 17 December 2015

The Bluestone Circle erratic assemblage

A journalist said to me the other day:  "But if the bluestones at Stonehenge are all glacial erratics, why are they all such beautiful pillars?"  I had to explain patiently that some of them (especially in the Bluestone Horseshoe / Oval) are indeed tall and elegant, but that those in the circle are a mottley collection of slabs, stumps, wedges etc -- many recumbent or partly buried and very unspectacular indeed.  They are for the most part heavily abraded boulders such as one might see close to any glacier front in the world.   For the record, above are some of the images from the wonderful "Stones of Stonehenge" blog site.  Click to enlarge.  For further information, go to the site itself.

The Stones of Stonehenge

A site with a page devoted to each stone at Stonehenge

As provenancing work continues, I'll try and update the details below.

Twenty stones in the Bluestone Circle:

31 -- damaged and heavily worn slab.  Standing.  Recent damage close to ground level. Spotted dolerite.
32 -- heavily worn slightly elongated boulder.  Fallen -- resting on another stone.  Spotted dolerite.
33 -- well worn short and stumpy pillar.  Standing.  Signs of shaping -- meant as a lintel? Spotted dolerite. From Carn Goedog?
34 -- well rounded small boulder, placed on end.  Spotted dolerite.  From one of the "other" outcrops?
35 a and 35 b -- irregular and well worn boulder, embedded in the ground and only just visible.  Spotted dolerite.
36 -- an irregular and heavily worn boulder, slightly elongated.  Modern damage on one edge.  Recumbent.  Mortice holes -- once used as a lintel?  Spotted dolerite.
37 -- smallish well-rounded boulder, slightly slab-shaped and set on end. Spotted dolerite.  From Carn Goedog?
38 --  smallish irregular boulder, well worn, fallen and under another stone. Ignimbrite / tuff.
39 -- another smallish boulder, well worn, slightly slab-shaped, with some later damage.  Leaning, almost recumbent. Spotted dolerite.
40 -- boulder?  Just top seen.  Rhyolitic tuff.
40g -- below ground stump -- irregular shape.  Lead cover.  Mica sandstone.
41 --  recumbent elongated boulder with heavy wear -- very well rounded edges.  Spotted dolerite.
42 -- recumbent wedge-shaped stone with heavy wear on edges. Spotted dolerite. From one of the "other" outcrops?
43 -- recumbent slightly flattened boulder with heavy wear on edges.  Spotted dolerite.  From one of the "other" outcrops?
44 -- heavily worn boulder just visible in the turf -- recumbent.  Unspotted dolerite.
45 -- recumbent elongated boulder with heavy wear on edges.  Unspotted dolerite.  From Cerrig Marchogion?
46 -- slightly slab-shaped boulder set on edge.  Flaky -- considerable recent surface damage.  Rhyolite.
47 -- slab with heavy wear on edges -- set on end. Spotted dolerite.
48 -- small recumbent boulder with heavy wear --  just projecting through the turf.  Rhyolite.
49 -- small irregular slab with quite sharp edges.  Upright.  Signs of dressing? Intended as a lintel?  Spotted dolerite.  From Carn Goedog?

NB.  In the heading I'm not calling them "glacial erratics" although I do incline towards that interpretation!  For the record, an erratic is simply a stone which is in an anomalous position, often a long way from its place of origin.  There are many processes that can transport erratics from A to B.

New Rhosyfelin Paper -- Photo Gallery added

Following requests for more images to illustrate the points we have been making in the "Archaeology in Wales" paper, published on 14th December,  we have now taken advantage of the Researchgate facility for adding data sets and supplementary information.

We hope these photos (of modest quality because of uploading constraints) will be helpful for those readers who are trying to work out for themselves what on earth went on at Rhosyfelin in the distant past.......

Hen-felin (near Rhosyfelin)

Following an earlier post, I have had a request from a faithful blog reader for some more info on the precise location  of the supposed "Rhosyfelin Mill".  The site is shown above as the orange rectangle -- the yellow one marks the site of the Rhosyfelin rocky ridge.

From the DAT  record (below) it does not look all that certain that this is -- or was -- a mill.  I shall go back again in the winter and check out whether there are traces of a leat or a fulling pond.  It is possible that the tree-lined paddock on the south side of the river was connected to the cottage.  There are certainly other features to look at, including trackways, stone walls and embankments.

This is the Dyfed Archaeological Trust record:

Primary Reference Number (PRN) : 19076
Trust : Dyfed
Community : Eglwyswrw
NGR : SN1144735963

Site Type (preferred type first) : Post-Medieval Cottage / Post-Medieval Mill

Summary :
'Hen-felin' is recorded on the historic Ordnance Survey maps, its name indicating a mill site. The building is still shown on modern maps (M.Ings, 2014)

Description :
The site was visited as part of the Cadw funded Mills Survey of 2012-14. Located within woodland, it is now abandoned, ruinous and overgrown. It is built of rubble stone into the slope above a stream. The walls still stand to approximate full height but the building is now roofless. No features were evident to confirm the building as a mill, and it appeared to be a deserted cottage, with a fireplace in each gable (M.Ings, 2014).

Mill site identified from Ordnance Survey and Tithe maps. Suggested date of late 18th century to early 19th century. Present condition unknown.

Sources :
Ordnance Survey , 1889 , 1st edition, 1:2500, Pembrokeshire Sheet 11.02
Ordnance Survey , 1907 , 2nd edition, 1:2500, Pembrokeshire Sheet 11.02
, 1840 , Nevern Parish Tithe map and Apportionment ,
OS , 1891 , First Edition Pembrokeshire Sheet XI NW ,
OS , 1964 ,

Wednesday 16 December 2015

On rockfalls from rock faces

 One of the excellent Aerial Cam photos taken from above the dig site at Rhosyfelin.  The big rectangular block (the "picnic table" as the locals now call it) looks to be gloriously isolated, but that is because other blocks and debris contained in slope deposits have selectively been removed from around it.  It has in other words been "prepared for presentation".......  Note that the block is located directly beneath the highest part of the crag, where other large blocks are now loose and are almost ready to fall too.....

"In September 2011 we started by digging a trial trench. We came down right on top of a prone 4m-long monolith, lying 4m from the edge of the outcrop. It seemed to have been manoeuvred into position by prehistoric quarry-workers and then left there. A large, jagged block had splintered off its underside, perhaps the reason why it was never moved out of the quarry."

Parker Pearson, M., Pollard, J., Richards, C., Schlee, D., and Welham, K. (2016).  "In search of the Stonehenge Quarries,"  British Archaeology, Jan/Feb 2016, pp 16-23.

Leaving aside the host of questions that are begged in that short extract, what intrigues me is the ongoing insistence on the part of the archaeologists that the pseudo-proto-othostat is in an un-natural position.  Let's explain yet again that there is nothing remotely problematical about the large rectangular block, given its position beneath the highest part of the crag. As I have asked before, if it is deemed to be lying in the "wrong" position, what is the "right" position supposed to be?

I bring this up now because today we went for a pleasant walk to Abereiddi and Porthgain.  At the latter place there is a dolerite quarry which worked till about 1930, with clean faces up to about 20m high.  If you think there is anything at all unusual or "man-made" about the rock face and rockfall bank at Rhosyfelin, just take a look at these pics:

Close-up of the rockfall debris bank at Rhosyfelin.  Much debris has been removed from the foreground.
Rockfall beneath a quarrying rock face in the Porthgain dolerite quarry -- abandoned around 1930.  Note the "random" arrangement of the blocks, some of which are almost 10m away from the rock face.

A rockfall from one of the lower faces at Porthgain dolerite quarry.  This fall has occurred within the last 85 years.  Here we see mostly large blocks.  One elongated block about 6m long is resting precariously, and will certainly move again when another rock fall occurs or when the bank settles.

Rockfall beneath a near-vertical abandoned face at Dinorwig slate quarry, North Wales

 Rockfall banks beneath another abandoned quarry face.  Here several "cones" have accumulated beneath gullies and have coalesced into an apron of scree incorporating very large blocks.

Two rockfall cones beneath an abandoned quarry face.  One consists of finer shattered debris in a discrete cone, and the other is a jagged pile of rubble incorporating very large blocks.

I still cannot understand that in the Brit Arch article, and in the Antiquity article, the authors (including two geologists) have not made ANY mention of the dramatic and prominent rockfall accumulations that mask the base of the Rhosyfelin rock face and which are interbedded with the radiocarbon dated horizons.  Have they really spent 5 seasons crawling about all over this rockfall bank, laboriously recording the position of every largish stone, without knowing what it is they have been looking at?

Memo to archaeologists: glacial transport theory is alive and well

After years of being disparaged and dismissed by archaeologists as "moribund" and "discredited", the glacial transport theory is actually alive and well -- and even appears to be undergoing something of a resurgence..........

A few things have intrigued me since the appearance of the article in "Archaeology in Wales" journal 3 days ago:

1.  In less than 3 days the article has been read almost 250 times on Researchgate;  that's an amazing response to something that one would have thought would be of very marginal interest.  I can only assume that the majority of readers will be archaeologists -- and for many of them this will have been their first realistic encounter with geomorphologists who have something to say on an archaeological topic.  It follows that they will also be forced to confront the weakness of the human transport theory and the relative strength of its competitor!

2.  While the press release which we put out has had nothing like the exposure of the media pack out out by university press offices on behalf of the MPP research team, with extremely expensive press agency assistance, it has nonetheless been picked up by all the main UK newspapers and by the BBC (two BBC World Service interviews so far).  That's quite unusual for something sent out "cold" with no advance briefings, from a totally unknown source.  To some extent the media are feeding off one another, with copycat reporting going on.  But that does indicate that journalists and editors find the story interesting.

3.  Most interesting of all, the quarrying spat is featuring in all the media coverage, but the thing that they are all seriously excited about is the GLACIAL TRANSPORT THEORY.  I keep on telling journalists that this is not a novel idea at all, and that it's been around for more than a century, but as far as they are concerned it is new, challenging and even rather wacky............ and who am I to disabuse them?  On the two interviews I did for the BBC World Service, the interviewers were not really interested in quarries at all (that was what I wanted to talk about), but they wanted to know all about how glaciers work.

So I sense that the tide is turning -- and that it will not be possible in the future for archaeologists simply to dismiss the workings of glaciers as irrelevant to the bluestone debate.

Tuesday 15 December 2015

Rhosyfelin -- the date near the crack

With respect to the theory that a rhyolite orthostat was taken from a "recess" near the tip of the Rhosyfelin spur, I have been looking again in wonderment at the following extract from Parker Pearson et al, 2015:

"The most probable dates associated with the removal of the rhyolite pillar from its recess are c 4590 BP and c 4667 BP, provided by carbonised hazelnut shells from the small occupation layer just 1.5m away from it."

This is pretty extraordinary. 

Here's a story. Somebody visits Stonehenge and looks at it from a hundred metres away.  He wonders when it was built.  He asks a passer-by how old the monument is.  The passer-by picks up a discarded newspaper from the road, which has yesterday's date on it.  "Of course!" says the visitor.  "That shows that it was built just yesterday!  Isn't that amazing?"

Another story.  Somebody looks in wonderment at a cave in the cliffs on Newport Sands.  He wonders how old it might be,  and then notices an old can of cooking oil among the flotsam and jetsam on the beach nearby.  Purely by chance, it has the date 2003 printed on the side of it.  On that basis, he decides that the cave was formed in the year 2003 by the same fellow that used the cooking oil.

Illogical?  Yes indeed.  Enough said.

The paper:  Mike Parker Pearson, Richard Bevins, Rob Ixer, Joshua Pollard, Colin Richards, Kate Welham, Ben Chan, Kevan Edinborough, Derek Hamilton, Richard Macphail, Duncan Schlee, Jean-Luc Schwenninger, Ellen Simmons and Martin Smith (2015). Craig Rhos-y-felin: a Welsh bluestone megalith quarry for Stonehenge.   Antiquity, 89 (348) (Dec 2015), pp 1331-1352.

Ceibwr -- three meltwater channel generations

On clearing out some old files today, I found this splendid old oblique aerial photo showing the Ceibwr channels.  Remember that when these were cut there would certainly have been no coast here, and no sea.  When meltwater was flowing in these channels, it was flowing along a hydrostatic pressure gradient, seeking out a lower and easier route beneath and out of a melting glacier.

The big channel -- flowing from the village of Moylgrove -- is on the left. In the centre of the photo we see a substantial rock ridge, and beyond it is Channel 2, a subsidiary arcuate and humped channel with a clearly defined intake point overlooking the present beach in Ceibwr Bay.  It's a rather spectacular small channel running out to the coast.  And incised into the floor of that one is Channel 3, a small one which is made up of a series of linked pot-holes.  That has to be the most recent of the three features.  The chutes which must have acted as feeders for the subsidiary channel may be contemporaneous -- there is no way of telling.

Note the obvious parallel with Craig Rhosyfelin -- big channel, rock ridge, and smaller channel........

I think these channels might be rather old -- maybe going all the way back to the Anglian Glaciation, around 450,000 years ago.  If they were Devensian, we would not find these old cemented and stained gravel deposits within the channel walls.  On the other hand there does not appear to be much Devensian till or meltwater deposits here either -- which suggests that the channels were used by meltwater again while the Devensian ice was melting away from this area around 18,000 years ago.  The best exposure of the Devensian till is within Channel 3.

More work must be done here -- meltwater has clearly been flowing subglacially from SE to NW.  But that is precisely opposite to the expected meltwater flow direction during the Devensian, since the ice gradient must have been NW - SE.  So we come back again to the thought that maybe these channels date from a time when Welsh ice, rather than Irish Sea Ice, was the dominant force in North Pembrokeshire........

The big channel now occupied by Ceibwr Bay.  The rock ridge is on the left.

 The rock ridge and the subsidiary channel to the right of it.  View inland from the coast.

Channel 3, which contains both cemented and uncemented deposits.

See also this post: