Planet Earth -- still more interested in myth than reality?

 At the end of this piece I have posted  the new report on the NERC web site of the latest research by Bevins, Ixer and Pearce on the Carn Goedog rock identifications: 

"Carn Goedog is the likely major source of Stonehenge doleritic bluestones: evidence based on compatible element geochemistry and Principal Component Analysis"
Richard E. Bevins, Rob A. Ixer, Nick J.G. Pearce
http://www.sciencedirect.com/science/article/pii/S0305440313003956

ABSTRACT:  The Stonehenge bluestones were first sourced to outcrops in the high parts of the eastern Mynydd Preseli in SW Wales by H.H. Thomas in the early 1920s. He recognised the distinctive ‘spotted dolerite’ from his fieldwork in that area and suggested that the tors of Carn Meini (also known as Carn Menyn) and Cerrigmarchogion were the most likely sources. In the early 1990s, in a major contribution to our understanding of the Stonehenge bluestones, the geochemistry of a set of samples from Stonehenge monoliths and debitage was determined and compared against the geochemistry of dolerites from the eastern Mynydd Preseli by a team from the Open University led by R.S. Thorpe. They argued that the majority of the Stonehenge dolerites could be sourced from outcrops in the Carn Meini-Carn Gyfrwy area, based on the concentrations of the so-called ‘immobile’ elements (elements which are not affected by rock alteration processes), in particular TiO₂, Y, and Zr. However, these elements are incompatible during crystallization of mineral phases in basaltic systems (that is they do not enter into the mineral phases which are crystallizing but are concentrated in the residual liquid) which severely hampers their use in discriminating between different pulses of an evolving magma (as is the case of the doleritic sills emplaced high in the crust and now exposed in the Mynydd Preseli). An alternative strategy in this study re-examines the data set of Thorpe's team but investigates the concentration of elements which are compatible in such basaltic systems (that is elements which do enter into the crystallizing mineral phases), namely MgO, Ni, Cr and Fe₂O₃. On the basis of the abundances of these elements on bivariate plots and also by using Principal Component Analysis on the dataset available and various sub-sets we identify three compositional groupings for the Stonehenge doleritic monolith and debitage samples and conclude that the majority of them (Group 1 of this paper) can be sourced to the prominent outcrop in the eastern Mynydd Preseli known as Carn Goedog. We also offer potential sources (with one exception) for those Stonehenge dolerites which appear not to relate to Carn Goedog.

We have looked at this paper before, so there is no need to analyse it again.  What's interesting is the article, published in a journal (web based) devoted to the Earth Sciences.  Look at the heading -- totally absurd, since presumably the author is an earth scientist herself.  Could she not bring herself to say " New evidence brings bluestone human transport theory into question" or something similar?  That shows us just how far the human transport myth has penetrated deep into the souls of people who should know better.......  even within the Earth Sciences research community.  How sad.

As for the article, it's pretty straightforward, and it's good to see that HH Thomas's science and his motivation are at last being questioned by professional geologists -- as I have done often before on this blog.  Just put "HH Thomas" into the search box to uncover some of my past comments.....

Assuming that Richard Bevins is being quoted correctly, he does seem to be getting much more critical and questioning of the archaeological orthodoxy.  At last!!

This is the key para:  "If Carn Goedog is the true origin of the dolerites, and Craig Rhos-y-felin is a source of the rhyolitic bluestones then it does bring into question the stones being transported by rafts down to the Bristol Channel, because both of these outcrops lie on the northern side of the Preseli Hills. The rocks would have had to be dragged up the hills, across the summits and back down again before they even reached the waterways. It's just not likely," Bevins concludes.

Welcome to the club. But if Richard was prepared to go this far, why could he not just have added:  "The locations of these possible source areas on the north -- or up-glacier - flank of Preseli is entirely in tune with glacial theory, and increases the likelihood that the stones are glacial erratics picked up by over-riding ice and transported at least part of the way towards Stonehenge."

Now if he had said that, and if it had been reported in this short article, we might have an indication of  earth scientists actually taking seriously the comments of their own colleagues, instead of going with the archaeological orthodoxy.  And if you think that indicates a degree of frustration on my part, you would be quite right.......

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Did humans transport Stonehenge rocks further than previously thought?

17 February 2014, by Harriet Jarlett

http://planetearth.nerc.ac.uk/news/story.aspx?id=1611&cookieConsent=A

Scientists have pinpointed the exact source of many of the rocks used to build Stonehenge.

A new study, published in the Journal of Archaeological Science, suggests that the site researchers had previously thought was the starting place of many of Stonehenge's rocks may not have been the source after all. Instead, it looks like the rocks actually come from a different site three kilometres away.

The findings, bring into question the long-standing theory that people transported the rocks from Wales to Wiltshire in order to build the monument.
The research focused on the smaller stones at Stonehenge, called bluestones. The chemistry of these rocks varies, but they all originate from the Preseli Hills in Wales and are thought to have been transported to the Stonehenge site over 4000 years ago.

By confirming the source of the rocks, the researchers hope to help answer the long standing question of how around 80 of these bluestones, weighing up to three tonnes each, were transported 250 kilometres from southwest Wales to Wiltshire.

'The Holy Grail question is how were the stones moved and why,' explains Dr Richard Bevins of National Museum of Wales who led the research. 'Many people think humans transported the stones south, down from the Preseli Hills and then up the Bristol Channel on rafts. But a second school of thought says these rocks are glacial erratics that were transported by ice to Salisbury Plain and so were available in the local environment.

'We're trying to discover the source of the stones so archaeologists can excavate sites in order to see if they can find evidence for people working the source stones,' he continues.
Scientists have known the bluestones originated from the Preseli Hills since 1923, when H. H. Thomas from NERC's British Geological Survey recognised the distinctive dark grey spotty rocks, known as spotted dolerites, during fieldwork. Further work in the early 1990s then tried to tie down the specific locations of the rocks' origin by matching the chemistry of the Stonehenge bluestones with those at the proposed origin site.

'The earlier research looked at the source of one of the spotted dolerites and tied it down to a specific outcrop, Carn Meini. It seems Thomas wanted all of the bluestones to also come from that same small area so he argued the rhyolites came from a nearby outcrop, Carn Alw. When we looked at it again we realised the descriptions of the rhyolites from Carn Alw and those at Stonehenge didn't look the same at all,' says Bevins.

The team took images showing the rocks at Stonehenge and the rocks at Carn Alw. They then asked members of the public with no geological background whether they looked the same.
'We asked people "does A look like B?" and everyone said no,' Bevins continues. 'This is astonishing because this has not been questioned since the original publication by Thomas in 1923.'

The team used a new method of identifying the chemical makeup of the rocks, to match the rocks with their origin. They believe that they have now identified Carn Goedog as the source of at least 55 per cent of the spotted dolerite bluestones at Stonehenge.

'If Carn Goedog is the true origin of the dolerites, and Craig Rhos-y-felin is a source of the rhyolitic bluestones then it does bring into question the stones being transported by rafts down to the Bristol Channel, because both of these outcrops lie on the northern side of the Preseli Hills. The rocks would have had to be dragged up the hills, across the summits and back down again before they even reached the waterways. It's just not likely,' Bevins concludes.