Some of the ideas discussed in this blog are published in my book called "The Bluestone Enigma" -- available by post and through good bookshops everywhere. Bad bookshops might not have it....
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Monday, 26 October 2015

Rhosyfelin reverts to nature

After all that quarrying by the MPP tribe over the past five Septembers, all is quiet again down in the valley.  The dig site has been filled in and re-seeded, and this is what it looked like about a month ago.  The big "pseudo proto-orthostat" is still exposed, as is much of the rock face and the upper part of the rockfall bank, but all of the interesting sediments and the cut sections are now lost without trace.  That's a pity, given that there is going to be a considerable controversy over the coming months about what is there and what it all means.  So the evidence is no longer available for scrutiny by independent experts, and people will have to depend upon the reliability -- or otherwise -- of what appears in print.

Thank goodness I have been able to post scores of photos of the site onto this blog, which specialists can search for and examine. If necessary, of course, new trenches can be dug and boreholes can be put down, but great care will have to be taken because in some places the top 2m or so of sediments will be infill shunted in from the big spoil heap which was located adjacent to the dig.

Before long, this will all be green again, until somebody or other moves in with picnic tables and information boards........


Myris of Alexandria said...

Is the very end stone the important site 8 the Jovian texture stone.
What about a blue plaque and some gushy words.
I think they have left a very tasteful ancient monument. Add a little rosebay willow herb and foxglove for colour and job done.
It all came together one Wednesday afternoon before the q word was thought.

BRIAN JOHN said...

Yes -- point 8 was right at the end of the spur. By the way, I'm still not convinced about that provenancing. I haven't seen anything from Stonehenge that looks identical. Similar in some respects, yes, but not identical enough to justify the "few square metres" tag. Show us your "best" slide from Rhosyfelin and your "best" slide from Stonehenge, and let us decide what to believe......

R.A.Ixer said...

No are no judge in this matter, worse hat that you are no open-minded. Your opinion on detailed petrographcal analyses is totally valueless. It is arrogance for you to think otherwise. reverse the roles and imagine your response were I to say that your Pleistocene field work did not convince me. Only the stupid pontificate outside of their expertise and only the wilfully blind persist.
I made my first attempt at petrography exactly 50 years ago this month and have seen and described in detail many thousands of slides (they take me a a day just to get the feel of them). I improved over half a century and now have a excellent and hotly defended international reputation as a detailed petrographer.
I repeat most of the rhyolites, namely Group A-C they are really Group C come from CRyf and could come from the plane of the quarry face and the best fit for the Jovian debitage is site 8 and within a few metres of it.
The data are in our publications with abundant photographs and I most publically thank enormously the ferret club for allowing so many of them in the almost annual publications. The photos and the descriptions will remain the benchmark for decades perhaps centuries.
Exactitude is meaningless in this context as you very well know. Two thin sections from the same hand specimen and not exactly the same unless the rock is very fg and dull.

BRIAN JOHN said...

Well well Rob -- this is all very formal, and not even with a cloak of anonymity wrapped around it. Calm down and take it easy.

I'm not calling you a fraud or a charlatan, or questioning your professional skills and integrity. All I'm doing is saying I'm not convinced that you have demonstrated that some of the debris at Stonehenge has come from an area about 3m x 3m at the tip of the Rhosyfelin spur. I have said that often before, and will probably say it again. If I had refereed that paper of yours I would have said it in my report to the Editor too. All of us who write papers get questioned, sometimes by people whom we consider to be less expert than ourselves. Get used to it. Show, don't tell. If it helps, the other academic geomorphologists who have looked at this site have asked whether you can do this sort of incredibly detailed spot provenancing without first having a very dense sampling grid across quite an expanse of countryside. Call them all stupid if you will....

By the way, I quite enjoy having my geomorphological ideas questioned on this blog, even by petrographers. You have frequently said that you are not convinced. So I have to keep on assembling evidence, and presenting it. Keeps me young. I have a reputation too, and hope it is still intact.

R.A.Ixer said...

I did not for one second think you believe I am a fraud or charlatan,why would you?
Like football it is more serious than that, your accusation is one of academic recklessness.
I am not certain where the 3x3m areas comes from I feel certain I have talked of provenancing on a decimetre scale meaning tens of metres, is decimetre, the wrong word??

You have not to my knowing, ever seen a piece of Stonehenge debitage, seen a thin or polished thin section of any piece of debitage but write as if you can sensibly give an opinion on them. You cannot and more importantly should not try to allow the impression you can. We should stick to what we know, read what is written and appreciate that.

Our data are there for the competent to judge and criticise and be listened to and argued with, the incompetent can do the same but will irritate and be ignored, largely.

Brian only in our obits will our reputations be given kindly. There will be little said about what awkward, almost impossible to work with, buggers we both are.

Still we are Mother Mary compared with Rainbow-hued Newton.


BRIAN JOHN said...

Rob -- academic recklessness? Your words, not mine. Just a reminder:

Digging into Stonehenge’s past
The provenance of Stonehenge’s rocks has been a subject of heated debate for many years.

Rob Ixer explains how the contents of a small box led to the discovery of the first secure Stonehenge-related quarry

Mineral Planning,issue 143 / October 2012

With respect to Rhosyfelin and JF Stone's little box of stones from the Stonehenge area:

"..........matching the distinctive ‘rhyolite with fabric’ debitage (first seen in Stone’s stones) from Stonehenge to very detailed sampling along the Welsh outcrop showed that rocks from the extreme north-east of Craig Rhos-y-felin (‘site 9’) were identical to Stonehenge rhyolites showing the‘Jovian’ texture. This suggests an almost impossible provenance of ten square metres. The archaeologists were told where to dig. In September 2011, Professor Mike Parker-Pearson of Sheffield University and his team cleared the vegetation from the northern end of Craig Rhos-y-felin and excavated. They found, just a few metres from site 9, a largeproto-orthostat, a large joint block set for its journey to Salisbury Plain. So the contents of a 60-year-old box led to the discovery of the first secure Stonehenge-related quarry site, confirming that man moved the bluestones..........."

In my book, and in most others, 10 sq m is an area approx 3m x 3m.

And all that talk about a quarry. How reckless is that?

R.A.Ixer said...

Ah yes that should be site 8, site 9 is away from anything at the other end of Cryf-rhyolite but ordinary Rhyolite C.

What is this from? something popular?? Is it Vexed? Rather chatty.

If I said that, it must be true, still 10 squared metres in big.

Quarry it is and quarry it will remain, not as difficult to swallow as a selective glacier whose only trace is the orthostats, not a lithic more not a lithic less, to misquote karma.

Still Brian nothing will convince you.


BRIAN JOHN said...

You said it all, Rob. Mineral Planning. Full citation provided. You make your bed and you lie in it....

Phil Morgan said...

For a fuller understanding of the glaciation v human transport debate, I suggest the excellent book "Science and Stonehenge,Oxford University Press,1999", edited by Professors B. Cunliffe and C. Renfrew, be made compulsory reading for all followers of Brian's blog.
The papers provided by Dr. C.P. Green (The Provenance of Rocks used in the Construction of Stonehenge) and Dr.J.D. Scourse (Transport of the Stonehenge Bluestones: Testing the Glacial Hypothesis), together with comments on the above papers by Dr. O. Williams-Thorpe being of particular interest to fellow bloggers.

A few copies of the book are currently available on Amazon at reasonable prices, and, before it is suggested, I'm not on commission.

BRIAN JOHN said...

Yes, we are familiar with all of that, Phil. This is the material on which Prof MPP bases his assumption that glacial transport of the bluestones was impossible. A very foolish assumption. As for Scourse and Green -- I have examined their contributions to that big book many times, and you'll find assorted entries by way of critical assessments in this blog and in the Bluestone Enigma book. In case you wondered, neither of those gentlemen would call himself a glacial geomorphologist, although others have called them glaciologists. Shall we say there are many others whose work in this field I would rather trust?

Dave Weston said...

As Brian says "We are familiar with all of that". What he doesn't say is that the sketch map showing flowlines for the Irish Sea and Welsh Ice, produced on page 117 of the Bluestone Enigma and labelled 'after Geoffrey Kellaway' which he uses to support the glacier theory has been amended since Kellaway produced it (1971). On the page 117 map immediately to the north of Stonehenge is inserted "ICE FROM THE NORTH? EXTENT UNCERTAIN" with no directional arrows, whereas the original Kellaway map of 1971 simply shows "NORTHERN ICE" with three arrows pointing from the north towards Marlborough Downs. I quote from Scours' paper in 'Science and Stonehenge pp 280-281:

"Kellaway has himself recently restated his conviction that the bluestones were transported by ice, but there are significant differences between this new synthesis (1991a,1991b) and his earlies views. Rather than invoking ingress of ice from the Bristol Channel during the 'Anglian', he now prefers possible transport from a more northerly direction during a Pliocene glaciation at 2.47Ma. He questions the exclusively south-west Welsh origin for the material and raises the possibility of sources from further north in Wales; particular prominance is accordingly given to a discussion of a boulder of ignimbrite which is similar to Ordovician rocks from Snowdonia."

Unfortunately,when trying to put forward support for human transport of the bluestones on this blog, just as there is no 'I' in team, there is no 'f' in point.

BRIAN JOHN said...

Lionel Kellaway was a good geologist but sadly his knowledge of geomorphology and glaciology was rather limited. So some of his ideas were distinctly wacky, and would not get much support nowadays. What James Scourse did in his article was to go after assorted Aunt Sally issues in order to demonstrate that Kellaway's ideas were nonsense, instead of concentrating on the main question of "Could glacier ice have carried erratics from the west and could it have left them on Salisbury Plain?" As I have mentioned many times on this blog, other geomorphologists and glaciologists who have thought about the issue have come up with the answer "Yes."

Dave W. said...

Typical Brian response, we now have a BBB radio presenter as a good geologist, footballers are next in line, and then it'll be sufficiently confused for glacial dissenters to say "sod it, its not worth the typing time".
Ice from the North, rather than the West, melts the glacial transportation idea.

BRIAN JOHN said...

I don't know what you are talking about, Dave. of course there was ice from the north -- just look at any map of the glaciation of the UK. The question is: where was its southern limit? There are scores of maps on this blog which seek to interpret the evidence. The Thames valley was glaciated, and the edge of the Cotswolds too -- there are certainly glacial traces around Oxford and Gloucester. What are you trying to say?

Dave W. said...

In Brian's caese it's "None so blind as those who don't wish to see", so not worth anymore typing time.

BRIAN JOHN said...

Did I say Lionel Kellaway? Oops -- sorry. Should have been Geoffrey Kellaway. He was indeed a good geologist. Not sure about the other chap.....

BRIAN JOHN said...
This comment has been removed by the author.
BRIAN JOHN said...

oops -- spelling mistakes. Try again. And I still don't have the faintest idea what Dave is all uptight about. No matter. Onwards and upwards -- found a nice moraine today. Will do a post.