Is the Glacial Theory now frozen out?

In the recent "exclusive" report of the Pont Saeson (Rhosyfelin) work, the Times reporter Norman Hammond quoted Rob Ixer as follows:

“The glacial theory is frozen out by this new evidence,” Dr Rob Ixer of Leicester University told The Times. If the stones had been transported east of the Bristol Channel by glacial action, a much wider range of sources would be expected. The pinpoint sourcing that has now been done argues strongly for human quarrying and transport of the bluestones.........."

That particular line has been used in headlines and as the underpinning of other media reports all over the world -- in the press, on TV and on radio, and in countless articles on the internet.   Rob has not denied the quote attributed to him, and it's clear that this position is shared by Richard Bevins, who continues to speculate about the "Newport Bay route" for bluestone transport, and by other commentators like Mike Pitts, Mike Parker Pearson and Geoff Wainwright.  On the telly the other night Mike Pitts more of less quoted the Times piece word for word -- and he has taken the same line on his own blog.

OK -- let's accept that the publication of an article like this will be trumpeted from the battlements by the authors and by their departmental media people.  That's accepted -- everybody wants to be loved and famous!  And of course the word "breakthrough" is over-used in such circumstances -- to demonstrate the value of a piece of work you have to "overturn" or "destroy" some pre-existing theory.  And the handy theory that is supposedly destroyed in this case is the glacial transport theory -- add some nice metaphors, and away you go!

But let's stand back and look at this in the cold light of day.  What has the new work actually done, with respect to the glacial transport theory?  If anything, it enhances the theory rather than damaging or destroying it.  My reasoning is as follows:

1.  As I have said before, this is not a piece of archaeological work.  It is a piece of straight geology -- an interesting and detailed exercise in provenancing.  It's not a breakthrough at all, in the sense that since Herbert Thomas made the initial identification that many (not all) of the Stonehenge bluestones came from the Carn Meini area, there has been a gradual homing in on the precise locations from which the stones were taken, either by ice or human agency.  The biggest leap forward was by the big Open University team project in the late 1980's, involving Olwen Williams-Thorpe, Rob Ixer and many others who used much more sophisticated techniques than were ever available to HHT around 1920.  Geologists have been getting closer and closer to matching individual stones to individual outcrops in the field -- such is the way with science.  There is a sort of continuum.   And now we have the claim that much of the rhyolite debitage (NB --  not the TOTAL debitage) at Stonehenge can be traced to Rhosyfelin.  No single stone has been provenanced with this accuracy -- we are just talking about lumps and chips found in the ground.  The fact that the work is now reported in an archaeological journal is neither here nor there -- the work tells us NOTHING about how the stones were moved.

2.  Some commentators on the new research (including senior academics) have suggested that the provenancing (or "pinpoint sourcing") of some fragments of Stonehenge bluestone to a POINT rather than a district somehow enhances the human transport theory and diminishes the glacial transport theory.  That of course is utter nonsense, for the reasons given above.

3.  While not diminishing or questioning the quality of the research  by Rob and Richard,  I have to say that I have read the paper carefully, and still have a few matters that cause me to feel uneasy.  Because the paper was published in an archaeology journal, was it refereed by archaeologists rather then geologists?  Perhaps the Editor will tell us -- because a paper like this should very clearly have been refereed by specialists in the same field as the authors.  There are some other things that need to be said too.  The "rhyolite debitage" referred to by the authors can only be the debitage that happens to have been examined (and collected) in assorted digs over the years -- the authors cannot know what lies beneath the surface in those parts of Stonehenge that have not been excavated.  So there could be a strong bias at the Stonehenge end of this research.  There could also be a strong bias at the Rhosyfelin end of the research.  The authors claim to have tied down the "source area" for the foliated rhyolites to within a few metres -- but you can only make a statement like that if you can demonstrate that there is no chance that identical rocks are found elsewhere in the district.  There are rhyolite outcrops in many different places in the Pont Saeson - Brynberian - Felin y Gigfran - Crosswell area.  Some of them appear to be roughly on the same alignment as the sampled Rhosyfelin outcrop.  Have ALL of those outcrops been sampled and eliminated as possible sources?  Perhaps Richard can tell us. 

4.  Then there is this point:  "If the stones had been transported east of the Bristol Channel by glacial action, a much wider range of sources would be expected."  Come along now, chaps, let's get real.  How many sources would you like?  We are up to 32, at the moment, I think, and still counting....... and a point which is not often made is that all of the foreign stones that we know about in the "Stonehenge total assemblage" appear to have come from the west.  That in itself is a persuasive argument for glacial transport.

5.  Finally, let's look at the location from which the "destroyed foliated rhyolite orthostat" is supposed to have come. (One or more?  It doesn't really matter.)  It is in a river gorge, on the flank of a rocky spur where a smaller channel runs down into a larger one.  A very difficult and constrained location.  Why would anybody want to quarry large orthostats from a place like this, either from a practical standpoint or from a ritual one?  You are just making enormous trouble for yourself -- since before you can do anything with your stones you have to get them up and away from this wretched river valley -- which would, by the way, also have been densely wooded during the Neolithic.  The large hole in the ground which MPP and his team kindly opened up showed one large stone and many smaller stones, in exactly the positions where we would expect them to have accumulated over many years of rockfalls and scree development.  But according to glacial theory this is one of many locations where, during the Ice Age, basal shearing could have occurred at the base of the Irish Sea Glacier as it flowed across the area.  If there was shearing, there could also have been entrainment.  I have gone over this many times before, so I'm not going to repeat it all again!

All in all, I cannot see any logical basis for the idea that the glacial transport theory has now been "frozen out" -- but I don't suppose that anything I say will halt or slow down the mad Quarry Hunt, since rational thought seems to be a thing of the past.