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Sunday, 13 December 2015

Rhosyfelin: manufactured evidence?

One of the Aerial-Cam images recently circulated to the world's media

This is an extract from the new paper, published today in Archaeology in Wales.   Interestingly enough, this section was not in the paper originally, but after reading the first draft of the text the referee and the editor of the journal suggested its inclusion.  They then accepted it without further modification.

In the extract, we examine the reliability of just some of the "installations" or "engineering features" referred to with gay abandon by the archaeologists who have worked at Rhosyfelin.  Sadly, assertions are not good substitutes for hard and convincing evidence......

The illustrations referred to can be found in the paper.

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)



Ever since 2011 the rock face at Rhosyfelin has been interpreted by certain archaeologists and geologists as a Neolithic quarry (e.g. Parker Pearson, 2013), and the debris banked against it is described as quarrying spoil. However, detailed investigations of the features at the site by the three authors of this paper suggest that there is no sign of human quarrying activity -- either related to the removal of monoliths intended for transport to Stonehenge, or for any other purpose. As suggested above, both the landforms and sediments owe nothing to human interference. It is worth itemising some of the “engineering features” described in the literature, in order to subject them to brief scrutiny.

“The quarry face”

The impressive rock face (Fig. 6) is the feature that has led the archaeologists to assume, after clearing away trees, shrubs and many tonnes of debris, that it is a worked quarry (Parker Pearson, 2012, 2013). The face does not coincide with a single fracture plane, but is made up of multiple surfaces, some set back more than 1.5 m behind others. The “smooth face” is an illusion, and it can be argued that it is simply an “archaeological artifice” created by the excavation team and unlike anything that might have existed in the past. Close to its tip there is much joint widening and evidence of block detachment and collapse guided by intersecting fracture planes. There are no traces of working with wedges or other tools, and there is no joint- guided ledge such as might be expected if the rock face had been systematically worked back from its original position.

“The quarry spoil bank”

The suggestion is that some of the larger blocks now exposed have been deliberately quarried by being levered from the rock face. Some blocks are indeed fractured and sharp-edged, as might be expected if Neolithic quarrying activity had been involved, but others at the surface are heavily weathered and also smoothed and rounded as a result of glacial and fluvioglacial erosion. Such blocks must have been emplaced around 20,000 years ago. Many blocks have weathered faces and “fresh faces”, just like those which are still in position on the crest of the ridge; the weathered faces are exposed to the elements, and the fresh faces are located on opening fractures or joints.

The “proto-orthostat”

Assertions that there is a single large “proto-orthostat” propped on wedges, pillars and rock “rails” (Parker Pearson, 2012; Ixer, 2012: 13) are not well founded. The large flat-topped slab appears to be in an entirely natural position, embedded in other rockfall debris and slope deposits following one of many post-glacial rock face collapses (Fig. 6). The stone is internally damaged by a series of fractures, and is so fragile (like other large stones at the site) that its chances of surviving even a short haulage expedition by land or sea would have been minimal. At a weight of 8 tonnes it is in any case far too large ever to have been thought of as a potential Stonehenge orthostat. It has fallen or slid into its present position at some stage after the deposition of the Rhosyfelin till.

“Props and pillars”

Beneath the enigmatic flat-topped slab the archaeologists have exposed compressed broken rock debris up to 30cm thick. This assemblage of rocks of all shapes and sizes, some of which are broken by percussive impacts, is referred to by the archaeologists as a set of pillars, pivots, props and packing materials put into position by Neolithic quarrymen in order to ease the movement of the “proto-orthostat” downslope. This material has been revealed by the selective removal of other adjacent material, and there is nothing to suggest that there has been any human interference. The “feature” referred to is an archaeological artifice.

“The stone rails”

Parker Pearson (2012) has referred to elongated and broken blocks of rhyolite up to 1m long located beneath and adjacent to the “proto-orthostat” as rock rails deliberately placed into position by quarrymen in order to ease the dragging of the large block downslope from the quarry face. However, there are many other elongated blocks scattered about through the rockfall accumulations, and there is no merit in the idea of human interference in their positioning.

“Scratched rock surfaces”

“Gouges” and “scratches” on the edges of fallen rocks near the “proto-orthostat” are deemed by the archaeologists to have been created when large blocks were hauled over them by Neolithic quarrymen; but after close examination these features are seen to be outcropping foliations typical of the Rhosyfelin rhyolite. Such features are seen on many rock edges throughout the site.

“The monolith extraction point”

Parker Pearson has pointed out to many visitors the “exact location” from which an orthostat was taken from the rock face and hauled or carried off to Stonehenge. That assertion appears to be based on the statement from Ixer and Bevins (2011, 2014) that they had provenanced certain rhyolite flakes at Stonehenge to “within a few square metres” of their sampling point 8, near the tip of the Rhosyfelin spur. However, they have not adequately demonstrated that level of precision, either through published thin sections from Stonehenge and Rhosyfelin samples, or through analysis of a very dense pattern of sampling points. The Stonehenge rhyolite flakes could even have come from a section of the spur which has been removed by the processes of glacial entrainment. Also, the “shelf” from which the monolith is supposed to have been removed is heavily abraded by either meltwater or ice action, indicating that it cannot have been quarried during the Neolithic.

“The working surface”

The suggested Neolithic “quarry floor” and other proposed anthropogenic surfaces have not been examined carefully because they have not been properly exposed. However, the archaeologists appear to have identified the red-stained till surface as the putative quarry floor or terrace (Parker Pearson, 2012). Thus if the archaeological hypothesis is correct, all of the sediments above the glacial and fluvioglacial layers at Rhosyfelin must have accumulated during the last 5,000 years. In other words, in this small valley with steep bounding slopes, there is no sedimentary record of the period between ice wastage and the end of the Mesolithic, spanning a period of c. 15,000 years. It is more likely that most of the sediments above the glacial and fluvioglacial layer at this site have accumulated gradually over a time-span of about 20,000 years, with the identified upper layers (Fig. 4) representing a sequence of climatic oscillations yet to be identified by radiocarbon and other dating techniques. In his 2015 lecture Parker Pearson confirmed that fragments of charcoal dating from the Mesolithic had been found, and this confirms the great age of some of these sediments. In addition, the top of the iron-stained zone is a pedological rather than a stratigraphic feature, and this too negates the idea that it coincides with a quarry floor or working surface.

“The haulage pathway”

This has been described by Parker Pearson as crossing a rough area of boulders and fluvioglacial sediments. Excavation on either side apparently revealed a hard packed route supposedly used for transport of stones from the quarry face towards the storage platform and the revetment. On close examination this too is shown to be nothing but an artifice, created by the archaeologists themselves. In any case this “pathway” is so irregular and full of boulders and other obstacles that it could not possibly have been of any use as a stone haulage route.

“The storage platform”

This is an area described near the outermost extension of the 2014 dig (Fig. 8). Again, it is very rough and irregular, with no clear outline or distinguishing features. It is in any case far too rough and bouldery to have been of any use as a ”stone depot” site.

“The revetment”

A proposed river bank and semi-circular “revetment” of large boulders was described in 2014 and 2015 by Parker Pearson in the gravels near the tip of the spur, on the edge of the main valley floor (Fig. 8). In his 2015 lecture he referred to this feature as a sort of quayside, linked to the supposed quarrying area and used for the trans-shipment of orthostats from the storage platform either onto river rafts or onto sledges, for export down the Afon Brynberian valley towards Newport Bay. However, these speculations are not supported by any stratigraphic differences between the supposed dry land and riverine environments, and all the boulders and cobbles in the vicinity are here interpreted as lying in entirely natural positions. Once again, they have been given prominence through the selective removal of surrounding materials.

“The export trackway”

In his 2015 lecture at Castell Henllys, Parker Pearson showed slides from a new pit dug during September 2015 out on the main valley floor. He claimed that after removal of fluvioglacial and riverine sediments, some sort of curving routeway could be seen, leading from the “revetment” and along the valley, heading north. He claimed that this feature had been cleared of stones and was defined by arranged boulders. On examination, this feature is seen to be entirely natural, with nothing to distinguish it from the exposed surface in other parts of the 2015 pit.

“The vertical stone fulcrum”

Close to the so-called monolith extraction point there is a small elongated stone which projects through the proposed “working surface”. It is leaning away from the rock face, and stands about 30 cm proud of the surface. It is referred to as a fulcrum, used with wooden logs for the leverage of monoliths from the quarry face. However, there is nothing to distinguish it from many other stones which project vertically or at high angles from a jumble of rockfall debris, till and fluvioglacial sediments. The only reason why this is called a fulcrum is that it is located in a “convenient” position.

“Packed sediment supports”

In his 2015 talk Parker Pearson described clay-rich “packed” sediments beneath large sub-rounded boulders in the vicinity of the “storage platform” (Fig. 8). He suggested that the material been “manufactured” in order to bind stones together in the creation of the platform. On examination, this material is seen to be nothing other than the clay-rich till which occurs across much of the dig site.

“Hammer stones”

Parker Pearson (2012: 406) referred to the discovery of abundant hammer stones in the Rhosyfelin dig site. He has claimed in lectures that some of these have percussion marks resulting from use in the quarrying process. However, he seems to have been unaware that there are thousands of such fist-sized stones at this site, dispersed throughout the glacial and fluvioglacial sediments. Many of them have surface fractures resulting from compression and impacts during transport. A search has not revealed a single “hammer stone” with the percussion marks that might be expected on a well-used Neolithic stone-working tool.

“The standing stone socket”

In 2012 a circular hole was excavated in the vicinity of a putative Neolithic hearth, near the tip of the spur. It was suggested by the archaeologists that it might have actually held a standing stone at some stage, or even that it was intended to hold the 8-tonne “proto-orthostat.” However, the sides of this pit were highly irregular, with many large projecting rock fragments, and no evidence has been presented for the compression of the sediments at its base, or for a distinctive infill. The pit has been filled in, and not mentioned subsequently, and again it appears to have been an archaeological artifice.

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