Perched block - Carn Arthur

 

I scanned this from an old print in my photo album.  It's the famous perched block on Carn Arthur, not far from Bedd Arthur (Arthur's Grave)  on the Preseli upland ridge.  If course, many blocks like this, stranded in precarious positions, are associated with heroic figures like Samson or Arthur.  Maybe King Arthur, having put this massive boulder in position, expired from the sheer effort of it all,  and had to be buried nearby.....?

Anglian and Wolstonian ice extent

This article contains a useful reminder that while we are all preoccupied with the Devensian Glaciation (naturally enough, since its deposits are all over the place) we must not forget that there were two other great British glaciations -- referred to as the Anglian (Elsterian) and Wolstonian (Saalian).  Gibbard and Cohen remind us that during both of these glaciations the ice of the British and Irish Ice Sheet (BIIS) covered Wales completely and also spread into Somerset and the Bristol - Bath area.  The Anglian Glaciation, around 450,000 years ago, was the more extensive of the two -- but not by very much.

The evidence in the field is difficult to interpret, but these two authors have assembled a vast amount of information, and I don't think they are far off with their ice edge reconstructions.  These do of course match quite closely the modelled glacier behaviour in the reconstructions by Hubbard et al and Henry Patton.  The ice edges are highly generalised, and it is highly likely that natural depressions such as the Somerset Levels must have been filled with ice coming from the west.

Did the ice reach Salisbury Plain on either of these two occasions?  This is a distinct possibility, and when MPP says that the glacial transport thesis is "dead in the water" because this vast ice extent was impossible, I just wish he would read some of the literature.

------------------------------

Quaternary evolution of the North Sea and the English Channel
Prof. P. L. Gibbard
(University of Cambridge, Cambridge Quaternary, Department of Geography)
Dr K. M. Cohen
(Utrecht University, Rhine-Meuse Delta Studies, Department of Physical Geography)

Proceedings of the Open University Geological Society
Volume 1 2015, pp 63-74

https://www.academia.edu/11960944/Quaternary_evolution_of_the_North_Sea_and_the_English_Channel

Abstract
The island of Britain is surrounded by a ‘moat’ of water, of which the English Channel and the North Sea are two major components.This talk described some major events that occurred to shape these seaways and, in particular, the evidence preserved on the Channel seabed. Here a system of valleys occurs that was carved by the westward-flowing Channel River. At its maximum in the last glacial period this river was larger than any other river in Europe today. It carried water not only from the rivers currently entering theChannel, but also from rivers flowing into the southern North Sea. Today the Holocene is characterised by limited glaciation and there- fore high sea level. However, for much of the time, global sea level was lower, exposing shallow areas as dry land.Throughout the last 2–3Ma, the build-up and decay of ice sheets on the continents have driven spectacular changes of global sealevel. Driven by climatic fluctuations, these sea-level changes resulted in cycles of emergence and submergence of the Channel floor. About 500,000 years ago the English Channel and the North Sea were flooded, as they are today, but unlike today there was a sub- stantial land barrier, the Weald–Artois ridge, that linked Britain to the European continent. During cold periods up to 500,000 yearsago the two seas were drained by separate river systems: the Channel River, aligned along the Channel basin’s axis, drained towardsthe Atlantic Ocean, while in the North Sea the major rivers flowed northward. Although there were earlier events, the first major extension of a continental-scale ice sheet into lowland central Europe and Britain occurred c. 450,000 years ago (the Anglian advance). Critically, this ice advanced across the emergent North Sea floor fromthe mountains of southern Scandinavia and Scotland, blocking the northward-flowing rivers and causing an immense glacial lake todevelop in the basin south of the ice front. Once dammed, the water that continued flowing from most of western Europe’s riverscaused the lake level to rise. The substantial land barrier of the Weald–Artois anticline held up the water and it was this barrier that was overtopped and breached. The narrow waterway thus formed became the Dover Strait (a.k.a. Pas de Calais), linking the NorthSea to the English Channel.The breaching of the ridge to form the Dover Strait was critical to the evolution of the Channel from then onward, up to the pres-ent. It forced the rivers Thames and Scheldt to flow through the new Dover Strait and into the Channel River. This drainage systemcontinued to evolve for the next 200,000 years, but events were brought to a climax some 160,000 years ago when a second major con-tinental-scale glaciation occurred (known as the Saalian advance). The resulting megafloods sealed Britain’s fate: during high sea-level periods it would henceforth be an island.The implications of such striking geographical changes for plant and animal — including human — migration are profound, result-ing, among other things, in the impoverishment of British flora and fauna during warm periods such as today’s British climate, but providing a major route between the Continent and Britain during glacial periods. In addition, the rapid release of huge volumes of fresh water in megafloods into the Atlantic Ocean could have triggered changes in oceanic circulation, which, in turn, could have affected the climate of the whole North Atlantic region.

Coming soon: Waun Mawn, the disaster movie

 

The disaster movie will probably be on the National Geographic Channel, since they probably have the film rights........

Why was prehistoric Wales singularly disinterested in stone circles?

Gors Fawr stone circle -- interesting, understated and rather unique......

The archaeologists all say the same thing -- that Neolithic Wales was singularly disinterested in stone circles -- in striking contrast to the Lake District, the Southwest Peninsula and Scotland.  Cromlechs (dolmens), standing stones and other stone settings are easy to find in Wales, but decent stone circles (as distinct from ring cairns and small settings of upright stones around burial sites) can be counted on the fingers of one hand.  Darvill and Wainwright, in Pembs County History Vol 1, claim that there were about 80 stone circles in Wales, accounting for six per cent of the British total, but I am not sure where they get that figure from -- I guess it is based on lots of assumptions about stone circles that are no longer present, or where somebody or other back in the good old days has speculated in the literature.......

In Pembrokeshire, although Darvill and Wainwright map six stone circles, there is only one that deserves recognition, and that is Gors Fawr near Mynachlogddu.  As everybody says, it's rather charming but not particularly impressive; and no attempt was made by the builders to use pillar-shaped stones.  Bedd Arthur, up on the Preseli ridge, is a strange stone setting, oval shaped and with a cluster of small stones leaning inwards......

In this context, the idea that there was a "giant stone circle" at Waun Mawn seems more than a little preposterous.  And the idea that there was some communication between North Preseli and Stonehenge with regard to the "magic diameter" of 110 m seems even more absurd.  If there was a stone setting of any sort at Waun Mawn it must have been crude and unfinished -- and a part of an assemblage of megalithic structures in the Tafarn-y-bwlch - Brynberian - Foel Eryr area.  At a rough count, there are at least 20 prehistoric structures using blocks of stone (all erratics) in the vicinity -- all ignored by Mike Parker Pearson and his team.

The impression gained from the prehistoric remains is that North Pembrokeshire did have a "megalithic culture" with links to Ireland and other parts of Wales, but that it was relatively unsophisticated.  It follows that there were probably not huge manpower resources available, and probably no awareness at all of anything further east than Carmarthen, let alone as far away as Stonehenge....

As we have seen, the evidence for a vast stone circle at Waun Mawn is extremely flimsy, and the evidence for Parker Pearson's exotic narrative of quarrying and bluestone transport looks ever more ridiculous.

Two big standing stones -- all that is left of the putative Bryn Gwyn stone circle.

By the way, here is one example of a short study which does demonstrate, rather conclusively, that there was a small stone circle on Anglesey.  The identification of stone sockets is accompanied by good documentary evidence and evidence of associated artifacts.  Infinitely more convincing than the work at Waun Mawn....... and I dare say that Bryn Gwyn has no connections with Stonehenge either.

Reference:

BRYN GWYN STONES, BRYNSIENCYN, ANGLESEY EVALUATION EXCAVATION 2008 PRELIMINARY REPORT
by George Smith
Cadw Project No. G1629 Report No. 790

http://www.walesher1974.org/her/groups/GAT/media/GAT_Reports/GATreport_790_compressed.pdf

Extract

Burl records about 900 stone circles in the Britain and Ireland, with several areas of concentration, but not in Wales where circles are relatively few and widely dispersed. In north-west Wales there are only two extant examples of large open circles, these being the Druid's Circle at Penmaenmawr and the circle at Bryn Gwyn. There are smaller circles around Penmaenmawr and at Cerrig Arthur, Meirionnydd and another possible at Pant y Llan, Arthog, Meirionnydd. There were also two probable examples, both destroyed, at Cae Coch and Cwm Mawr, both near Tremadog, Gwynedd. There are other circles with more numerous smaller stones that have more in common with ring cairns, to be found at Llecbeiddior and nearby Hengwm, Llanaber, Meirionnydd. The open circles of large stones at Penmaenmawr and Bryn Gwyn are distinctive and both lie close to other major monuments. At
Penmaenmawr there are large ring cairns and other types of cairns nearby and Bryn Gwyn is
close to the probable henge of Castell Bryn Gwyn, 300m to the north-east where pottery
suggests use in the Later Neolithic (Wainwright 1962). Further to the east at Tre'r Dryw Bach
another large circle, of smaller stones than at Bryn Gwyn, was also reported by 18 th century visitors but has since been cleared away. Study of the topography and of aerial photographs has failed to find any hint of the location of this second circle and it might be difficult to ever re-locate as its smaller stones may have left no obvious pits.

---------------------

This is a very relevant post from 2012:

https://brian-mountainman.blogspot.com/2012/03/stones-in-wales-wood-in-wessex.html

On the insignificance of Neolithic radiocarbon / OSL dates

One of the Waun Mawn stones. The same age as Stonehenge?  

Interesting, but hang on a moment.......

I was intrigued by the manner in which Prof Mike Parker Pearson (in his recent video) used the dating evidence from Waun Mawn as his "clinching argument" relating to the imagined links between that site and Stonehenge.  He went to great lengths to "fit" the Waun Mawn dates (or some of them) into the Stonehenge radiocarbon chronology -- using some to demonstrate "occupation of the site" at the right time, some to demonstrate the digging of sockets at the right time, others to date stone removal from the sockets at the right time, and others to date the export of the stones off to Stonehenge.  At the right time, of course.  Except, of course, that many of the dates were not at the right time at all, and could be conveniently ignored by MPP as being aberrations, bits of "residuality" or caused by contamination.  

It's all very weird, but the MPP team has done it before, at both Rhosyfelin and Carn Goedog, where wide scatters of dates have been fitted into the Stonehenge chronology  by ignoring most, using some, and assuming causal relationships. The dates actually falsify the quarrying hypothesis, but MPP and his colleagues claim that the dates (or at least a few carefully chosen ones) confirm it and fall neatly into their evolving narrative.

The only sensible way to interpret the dating evidence from these three sites (Rhosyfelin, Carn Goedog and Waun Mawn) is to say that it is effectively irrelevant.  If you were to visit any one of the thousands of Neolithic / Bronze Age megalithic sites in the British Isles,  dig up organic samples and then date them, you would -- with virtually 100% confidence -- expect them to come out between 3,500 BC and 2,500 BC.  OK -- some dates would come in outside of that "thousand year window",  for variety of technical reasons and maybe the odd local cultural aberration,  but that's how old the remains are because that is when the activity was going on.  We have talked of Neolithic tribes and settlements before -- just type "Neolithic population" into the search box on this blog and you'll see the posts and the discussions.  In the period under review agriculture and animal domestication were well established, people were beginning to use stones of all sizes for their structures, and they were living more sedentary lives, in settled communities.  But there was still a lot of hunting and gathering going on, and temporary camps were still being used in convenient locations for hunting, gathering and fishing expeditions.  As in many other parts of the British Isles, the landscape was well used and its resources were exploited on a much larger scale than during the Mesolithic or Early Neolithic, partly because the population was much larger.  Land was cleared by burning, charcoal and other organic remains were left behind, and camp sites were used and abandoned, with debris (including tools) left behind to excite the interest of future generations.

So why are such innocuous and commonplace traces of occupation flagged up as having vast importance? Answer:  because of the obsession with the Stonehenge bluestones.  Let's be clear about this -- the only radiocarbon and OSL dates that have any significance for Stonehenge are the dates obtained from within the Stonehenge landscape. All the others are irrelevant as far as Stonehenge is concerned -- although of course of interest for the dating of activities within the landscape of North Pembrokeshire, or wherever.

As I said in my last post, if MPP and his diggers can be bothered to do some excavations at Carn Alw, Carn Bica, Bedd Arthur, Gors Fawr or Bedd yr Afanc, they would certainly obtain a host of radiocarbon dates that would match very tidily with those obtained from the three "bluestone" sites about which they have got very over-excited.  In the absence of such control studies and comparative radiocarbon and OSL age determinations, the claims made about the uniqueness and the significance of the "bluestone quarries" and the "giant stone circle" are simply ludicrous.

Waun Mawn: the ruling hypothesis rules, OK?

I managed to take a look at MPP's 20-minute talk out "in the field" at Waun Mawn and issued by the NPA as part of their Archaeology Day promotion.  The NPA is trying to raise its profile through slick marketing, and it suits them to have a high-status hero (yet again!) to enthuse the masses with his particular brand of storytelling.  And obviously MPP is marketing himself and his ideas for reasons that are not too difficult to discern.  So this is not a scientific video but a marketing exercise -- and on that basis perhaps we should simply tolerate the fact that it consists of a string of assertions, assumptions and speculations and hardly any verifiable facts?

Well, yes and no.  It's not a scientific explanation aimed at a peer-group -- but it is such a complacent and biased version of reality that I'm amazed  that MPP had the brass to do it and I'm also amazed that the NPA is prepared to put up with it -- ignoring the fact that the cited evidence has never been examined by independent archaeologists and that the narrative in the video has never been tested through academic scrutiny either.  At every stage of the narrative inconvenient evidence is simply brushed aside as immaterial, the truth is twisted to fit the ruling hypothesis, and highly subjective interpretations of features on the ground are presented as established facts.  And as ever (this is getting boring) there is never any mention of the fact that aspects of the narrative (think quarries, overland routes, bluestone sources and Altar Stone provenance) are hotly disputed in the literature.  MPP seems to have a rather charming Trumpian view of science --"This is my truth, and if scientists disagree with me, tough luck, because they are wrong and I am right.  Other so-called experts should be ignored because they are probably charlatans...."

Let's just remind ourselves that there is NOTHING in the literature to back up what MPP is saying about Waun Mawn on this video.  The only two documents published by him and his colleagues are "field reports" from the 2017 and 2018 digging seasons, written in order to demonstrate to funding organizations that their grant aid has been well spent, and in order to elicit future funds for follow-up work.  Spectacular results and grandiose claims about the significance of findings are required in such situations, and the reports make no pretence of academic rigour.  Observations and interpretations are so scrambled that the texts and images are effectively useless for anybody seeking to understand what has gone on at Waun Mawn in the past.

That having been said, there is one brief study that does try to present evidence prior to discussing and interpreting it -- and that is my own "working paper" published on Researchgate, with a substantial input from a number of conversations with other observers:

https://www.researchgate.net/publication/345177590_Waun_Mawn_and_the_search_for_Proto-_Stonehenge

It's already had 143 reads, so somebody out there is taking it seriously, and I await disputatious feedback with relish!  It's interesting that many of the basic observations incorporated into my paper (relating to geology, landscape and other archaeological features) are completely ignored by MPP.

One interesting thing about this video is that MPP seems to make a virtue of being determined to confirm the ruling stone circle hypothesis come hell or high water -- and he seems inordinately proud of the fact that he came back to Waun Mawn and carried on looking for sockets even when the geophysics results provided no encouragement at all.  In fact his bloody-minded conviction and refusal to give up has now become a part of the narrative!  Heroic Indiana Pearson persists, against all the odds, and finally prevails!!  He seems blissfully unaware of the fact that when you are so determined to find something, you may well end up seeing what isn't there, and also manufacturing evidence to support your cause.........  Don't be surprised; they have done it before, at  Rhosyfelin and Carn Goedog..........

I could go through his talk sentence by sentence, pointing out his omissions, misunderstandings and misrepresentations, but I have done it all before, and there was essentially nothing new in the first part of the talk.  But there was some interesting material when it came to the radiocarbon and OSL dating commissioned by the research team.  

In brief, the radiocarbon dating (of around 40 samples?) proved to be very inconvenient, with most of the small carbonized wood samples proving to date from the Mesolithic.  Some of them were clearly found within the so-called "stone sockets" and had to be explained away as a consequence of downward particle movement assisted by earthworms.  Believe that if you will....... I think that on balance I prefer to think that the fragments were in their "right" positions on an undulating sediment surface, and that the claimed sockets are not sockets at all.  Let's wait and see the colour of the evidence.   Apparently there were four Neolithic dates, ranging from 3,600 - 3,000 BC.

The OSL dates were taken from the "sides of the sockets" -- what does that mean?  Were they taken from sediment fills, or not?  According to MPP,  five  sockets were dated to 3,800  BC - 3,200 BC -- ie 200 years before Stonehenge was built.  On this basis MPP argues that the Waun Mawn circle was erected before 3,200 BC, which would make it the third oldest circle in the UK.  But there appear to be other dates for "sediment fills" clustered around 2,000 BC --  and this leads him to conclude (goodness knows why) that the stones were taken away to Stonehenge around 3,000 BC -- very conveniently at just the right time to be used in the Aubrey Holes.  (As we may recall, MPP is convinced that the Aubrey Holes held bluestones before they were moved out and rearranged in something like their current settings......) 

Until we see the hard evidence of where these samples were taken from  and what the dating errors might be, it is difficult to know how to interpret the narrative being developed by MPP.  How many "inconvenient" dates are conveniently being ignored?  And what are the ages of all the other monuments in this neighbourhood?  They are not even mentioned by MPP, let alone studied.  Control studies and control dates do not figure in the grand scheme of things.

In spite of the bravado of MPP on this video, and in his other talks around the country, it's clear that the archaeologists are far from convinced about their "giant stone circle" at Waun Mawn;  they only have four stones (of very different sizes) in the putative circle, and six stone "sockets" that may of course be entirely natural.  The idea that these six irregular hollows held monoliths that have been removed is speculation, pure and simple.   The evidence is as thin as it ever was.   So their revised position is that the stone circle was maybe started and never finished. But they still have to sustain the pretence that 80 bluestones were transported from West Wales to Stonehenge, and the latest evolution of the narrative is that there may be another dismantled stone circle somewhere in the vicinity, waiting to be found, and that some stones may also have been exported directly from Carn Goedog to Stonehenge without being used initially in a local stone setting.  The narrative gets ever more convoluted..........

The most interesting thing about this video, and about MPP's take on local archaeology, is that it is actually all to do with Stonehenge, not North Pembrokeshire.  He and his colleagues are so obsessed with the "Stonehenge Neolithic mythos" that the significance of everything observed at Waun Mawn has to be measured in terms of its impact on Stonehenge.  This is exactly the sort of thing that Gordon Barclay and Kenny Brophy complained about in their recent article.  The obsession is distinctly unhealthy.....

Gordon J. Barclay & Kenneth Brophy (2020): ‘A veritable chauvinism of prehistory’: nationalist prehistories and the ‘British’ late Neolithic mythos, Archaeological Journal,
DOI: 10.1080/00665983.2020.1769399

https://brian-mountainman.blogspot.com/2020/07/bluestones-and-interpretative-inflation.html
https://brian-mountainman.blogspot.com/2020/06/the-origins-of-british-neolithic-mythos.html
https://brian-mountainman.blogspot.com/2020/06/the-politicisation-of-neolithic.html

So where are we now with the Waun Mawn situation?  As I said in my working paper on Researchgate, there might have been a small stone setting here in the Neolithic, and this might be quite early in British terms.  There might have been  a few more stones to start with, but the evidence on that is not convincing.  The setting, in terms of local Neolithic / Bronze Age archaeology, is interesting but not spectacular; stones were used singly or in groups, but there was no preferential use of spotted dolerite or foliated rhyolite, and no evidence that "quarried stone" was ever used.  Those who put up standing stones used whichever pillars or slabs just happened to be available in the vicinity.  And the Waun Mawn radiocarbon and OSL dates suggest that whatever was going on here was at about the same time as lots of other activity across the British Isles. The dating evidence from Rhosyfelin and Carn Goedog tells us nothing about quarrying, and simply confirms that there were people living in the area in the Neolithic / Bronze Age transition period.  But we knew that already.   There is nothing whatsoever at Waun Mawn to link it with Stonehenge, and no amount of fantasising is going to alter that fact.

                                       

Carn Afr -- and more glaciation traces

Carn Afr is a spectacular hillside tor  at an altitude of 380m n the southern flank of the Presely ridge, only a couple of kilometres away from the hamlet of Rosebush and almost due south from Foelcwmcerwyn summit. Its name can be translated as "the cairn of the goat".  The main feature of the tor is a prominent double pinnacle of rock which is visible from a great distance.  Around it there are small vertical cliffs, grassy steps and clean slabs of rock, with a litter of massive boulders especially to the west. There are several enormous perched boulders near the double pinnacle. 

The rock is for the most part rhyolite, but there are also other foliated or layered volcanic rocks including tuffs and trachyte lava. This is the only substantial tor on Preseli which is made of volcanic rocks belonging to the Sealyham Volcanic Formation, displaced by faulting; all the others are made of rocks belonging to the Fishguard Volcanics. There is only a little scree, at the foot of the lowest of the cliffs. The tor is reminiscent of Plumstone Rock, and it is deeply weathered. It look as if it has been battered by the elements since the beginning of time....... But the lower part of the rocky slope has abundant ice-smoothed outcrops indicative of ice action, with an upper edge around 365 m.

The double pinnacles ar Carn Afr -- visible from many miles away.

Fine-grained light blue/green (silica-rich) rhyolite exposed on the flank of the tor

Flow structures and cavities in the Carn Afr lava

Welded tuffs (?) exposed on a perched block on the lower part of the tor.

As one scrambles down the face of the tor, over a series of steps with minor cliffs and crags, the frequency of ice-moulded surfaces increases, and down on the grassy expanse below, in the vicinity of a striking sheepfold, almost all of the bedrock exposures are moulded and smoothed.

A steeply sloping ice-moulded surface towards the base of the tor, with abundant lichen growth on the surface

Ice-moulded rock exposure near the sheepfold.

Ice-moulded rock surfaces projecting through the turf, west of the sheepfold.

So the impression here is that ice moulding features are not at all marked on the upper paret of this tor, but are prominent on the lower part.  This is not to say that the upper part of the tor was not affected by Late Devensian ice; but it might be that at at some early phase of the last glaciation the whole tor was protected by cold-based ice, and that later on, with the ice surface somewhat lowered, active abrasion and surface modification occurred under a warm-based glacier thermal regime.