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Friday, 19 February 2016

National Park steps up pressure on "bluestone thieves"


 Ranger Richard Vaughan in the rain, up at Carn Menyn, holding some chunks of spotted dolerite that the stone robbers bashed off but failed to take away.......

There has been quite a bit of media coverage for the National Park's campaign designed to discourage people from collecting chunks of spotted dolerite from Carn Menyn and selling them on Ebay.  The BBC covered the story, as did the Telegraph, Mail and assorted other newspapers.  A typical report:

http://www.telegraph.co.uk/news/uknews/12164042/Stonehenge-tourist-bosses-demand-visitors-stop-chipping-stones-and-selling-them-on-eBay.html

Of course there is a considerable amount of nonsense in the reports, some of it encouraged by the contents of the press release, but it's hardly worth bothering about......... 

It's a matter of debate whether publicity of this type will actually reduce the amount of stone collecting from Carn Menyn (Carn Meini) or whether it will simply give even more people the idea that they can go up onto the mountain and collect "authentic" bluestone chunks that can be sold for large sums of money on Ebay and other trading sites.  In my comments to the National Park I tried to play down the "special place / revered outcrop / invaluable ancient heritage" theme by saying that there are plenty of perfectly splendid spotted dolerite boulders scattered about on farmland -- but the magical / mystical story is a key part of the National Park's bluestone narrative, and they can't resist using it whenever an opportunity arises!

Psst -- if you ask me nicely, I can get a nice bit of genuine healing bluestone for you, from right next to a healing spring, with a signed guarantee regarding authenticity...... at a very good price. If you aren't cured within a fortnight, just ask for your money back......

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

Here is the full press release:

For immediate release                                  Thursday 11 February 2016

Appeal to stop Preseli bluestone ‘burglars’

The Preseli Hills have been a special and spiritual place for thousands of years and are a crucial part of the Stonehenge story.
But as news of their significance continues to spread, more and more pieces of Preseli bluestone are being illegally removed from sites which are part of the Mynydd Preseli Site of Special Scientific Interest (SSSI) and Preseli Special Area of Conservation (SAC).
Academics from the world of archaeology and geology have joined the Pembrokeshire Coast National Park Authority in appealing to members of the public to stop taking fragments of spotted dolerite or ‘bluestone’ from protected sites such as Carn Menyn.
National Park Ranger Richard Vaughan said: “I walk the Preseli Hills with school groups, guided walks and on conservation work throughout the year and have noticed over the years that an increasing amount of stone chips and large chunks of rock are disappearing.
“It is very sad to think that to many the stones are very important, yet to others they are a possible source of income and taken away from where they belong.”
Pembrokeshire Coast National Park Authority Culture and Heritage Manager, Phil Bennett added: “If somebody took a hammer and started bashing chunks off a bluestone at Stonehenge there would be an outcry. To me, what is happening at Carn Menyn is just the same.”
“The vast majority of walkers go to the Preseli Hills to enjoy the wonderful scenery of the National Park landscape and we would ask that people please leave it as they found it for others to enjoy.”
Although the debate over how the bluestones made their way from the Preseli Hills to Stonehenge rages on, all sides agree that protected sites such as Carn Menyn should be left alone.
Archaeologist Professor Geoff Wainwright said: “As an archaeologist, Preseli is of far greater interest to me than any single monument. Carn Menyn is a special place with dramatic outcrops of bluestone, a concentration of archaeological sites, healing springs and a scatter of abandoned pillar stones which are petrologically indistinguishable from those at Stonehenge. 
“The Preseli bluestones hold the key to the meaning of Stonehenge and Carn Menyn was a special place from whence they came. To take fragments from Carn Menyn is to violate a part of our heritage which has been valued for over 4,000 years.
“When a piece of bluestone is removed from the crags at Carn Menyn, unique information about the past is lost and cannot be recovered. We have all been robbed.”
Geographer Dr Brian John added: “The spotted dolerite at Carn Menyn is no more beautiful and exotic than the spotted dolerite seen in scores of other sites throughout eastern Preseli.  As far as I am concerned, we have at Carn Menyn a group of very beautiful dolerite crags, affected by ice and frost action, which tell us a good deal about the landscape history of the area and which contribute hugely to the beauty and special character of the mountain landscape.
“There is no reason at all why anybody would wish to chip off lumps of rock from these crags and take them away, doing severe damage to the landscape, since identical spotted dolerites are found abundantly in all of the hedgerows and gardens of the countryside to the south of the hills. There are a good many to the north as well.
“Please leave these rocks alone and leave the landscape as you found it. If you are really desperate for a piece of spotted dolerite, get it (with permission) from a farmed landscape well away from the hills, from a location where boulders and stones are being cleared from fields."

Ends

Caption: Evidence of chunks of bluestone taken from Carn Menyn in the Preseli Hills.
Caption: Professor Geoff Wainwright next to one of the bluestones at Stonehenge.
Issued by Medi George, National Park Communications, tel 01646 624867 or email medig@pembrokeshirecoast.org.uk.

Notes to Editors
Sites of Special Scientific Interest (SSSIs) are the most important sites for Wales’ natural heritage. They help conserve and protect the best of our wildlife, geological and physiographical heritage for the benefit of present and future generations. Mynydd Preseli SSSI is of special interest for its habitats, species and geology. It is also recognised as one of the very best examples of a natural heritage site in Wales, the UK, Europe and is accordingly also designated as a Special Area of Conservation.
Sites of Special Scientific Interest (SSSI) are important as they support plants, animals and habitats that are rare, declining or unique; they also protect the best examples of Wales’s geology. SSSIs are legally protected under the Wildlife and Countryside Act 1981.  All SSSIs are protected by law from unsuitable management, damage or other activities. Where an SSSI is being damaged, Natural Resources Wales will attempt to resolve the issue. If this is not possible, Natural Resources Wales can begin legal proceedings, which can lead to a criminal prosecution and fine.

Wednesday, 17 February 2016

Glaciers in the Moroccan High Atlas



 Morainic ridges definining old glacier edges in the High Atlas (Photos: Philip Hughes)

Not many people realise that there have been many glaciers in the High Atlas Mountains of Morocco.  Here's a man who knows rather a lot about them:

http://www.qpg.geog.cam.ac.uk/people/hughes/

There is now quite a substantial literature from Philip and assorted colleagues, and a chronology is being put together.  It seems that there were small glaciers here in the Younger Dryas, in the highest areas (there are two peaks over 4,000 m) where snow accumulation was possible -- and snowfields and glaciers must have been much larger during the Devensian Glaciation.  But it appears from cosmogenic dates that there may be some strange things going on here, and no precise synchronicity with NW Europe.  Were there large ice caps in these mountains at some stages?  The researchers think that is possible, since there are many troughs, cirques, roche moutonnees and glaciated pavements to be seen, but much more field evidence needs to be collected before the situation becomes clearer.  All we know at present is that there are abundant moraines and traces of glacial action in at least 20 discrete areas through the High Atlas, and that the longest Devensian glaciers were up to 10 km long.



Sunday, 14 February 2016

Devensian till at Freshwater West?


This just could be something important.  I saw these two photos on Facebook today -- taken by somebody who has been wandering on the beach at Freshwater West following the recent storms.  It looks as if a lot of sand has been shifted out to sea, exposing an expansive bed of what looks like black clay.  But beneath the black surface we see a weirdly coloured bed of something that looks as if it might be clay till -- if you enlarge the top photo you can see that there are many stones of all sorts of shapes and sizes.  I'm trying to find out what these stones are like in close-up -- since I'm in Marrakech just now, it's a bit difficult to pop over and have a look.......

Let's assume that the topmost layer here has something to do with the submerged forest, which has been frequently described from Freshwater West.  In Newport Bay the submerged forest overlies a clay-rich till, and if this is also confirmed from Freshwater West, it will show that the Devensian ice was in contact with the Pembrokeshire coast well to the south of Milford Haven.  We already know that there is Devensian till at West Angle bay, on the south side of Milford Haven.   In turn, this will tie in with my suspicion that Devensian ice affected Caldey Island........

Watch this space.....

PS -- all photos are from Ivan Wooll.  Here is another, fresh from Facebook.  It looks more and more like till.



Saturday, 13 February 2016

Concerns about the Giant's Quoit at Porthleven


 Wow -- Porthleven has taken quite a bettering lately in the storms.  This photo shows the breaking waves at the height of the recent gale.  Hope the Giant's Quoit is still OK and remains where it was.  On the other hand, if the cliff face has been heavily battered, maybe more giant erratics might have been revealed.....

Sunday, 7 February 2016

Gateposts in the Whitland area


Whitland SN 167199.  Right in the middle of the town between the surgery and the Co-op.  This is a conglomerate, difficult to tell because it has been painted, but rounded pebble inclusions can be seen in the rear

Crosshands SN194234.   Gate post in slab material dressed to present a sloping design

Llanglydwen SN192268.  Slate gate posts, dressed to present a sloping design


From Dave Maynard, with thanks: 
Some gateposts I’ve noticed in the area north of Whitland.  Just a small sample, plenty of other big stones off the Preselis, these are just a few I’ve noticed.   I think I'll do a bicycle mounted survey when the weather is better, but before the vegetation grows too much.

The issue of mauls at the supposed quarries appears to have been avoided.  To get any stone out of the parent rock will result in lots of flakes and spalls.  The only other option is if they had previously been detached.

Wednesday, 3 February 2016

That "Jovian" fabric -- how accurate can "spot provenancing" be?






One of the interesting points that came up in discussions after my seminar last week in Swansea was the claim by geologists Rob Ixer and Richard Bevins that they have identified the source of some chips of "foliated rhyolite with Jovian fabric" at Stonehenge to within a few square metres of sampling point 8 at the tip of the Rhosyfelin spur.  I have dealt with this claim before, more than once, and have expressed my scepticism:

http://brian-mountainman.blogspot.co.uk/2014/04/on-significance-of-rhosyfelin-locality-8.htmhttp://brian-mountainman.blogspot.co.uk/2015/09/rhosyfelin-and-spot-provenancing.html
http://brian-mountainman.blogspot.co.uk/2014/04/rhosyfelin-foliation-plane.html

Although the geologists have been rather cautious about their interpretation, it has been seized upon with relish by the archaeologists -- and has led to all that wild speculating about the "monolith extraction point" which has been much photographed, mostly with MPP indicating exactly where a Stonehenge bluestone is supposed to have actually come from. Of course, he cites the geologists as his authority.   Has MPP been chastised by the geologists?  It does not appear so.......

Following my presentation, without any prompting from me, some of those present were mystified about the degree of accuracy claimed, on a craggy outcrop from which rock has been removed down through the millennia by a variety of different processes.  So herewith are my attempts to articulate the concerns:

As I understand it, the foliated rhyolites from across this area have subtle variations on the "Jovian" texture theme -- no two samples look precisely the same in thin section.  Presumably that means that each foliation layer has its own "signature" which is different from the foliation layers above and beneath it.  It does not appear that the geologists yet have enough detail -- at least not in the published articles thus far -- to say whether the "signature" of each layer remains consistent laterally, right across a foliation surface or plane.  Several other geomorphologists have pointed out to me that if a particular foliation plane has its own signature, then any point at which that plane is exposed (maybe miles away from Rhosyfelin) could be a source for the fragments found at Stonehenge.  We can see on the photo above that the foliation plane exposed in the yellow strip closest to the camera (the supposed "monolith extraction point") is also exposed at multiple other points across the face.  That face is not flat, and it is not a single fracture plane -- the face is made up of multiple fracture surfaces, some set more than 50 cms "deeper" than others.  So the celebrated fragments at Stonehenge could have come from any one -- or several -- of those exposures -- or more likely from exposures of that same foliation layer from parts of the crag long since destroyed.  Or -- and this is perfectly feasible -- from localities many miles away from Rhosyfelin.

Which brings me to the point that we still haven't seen a thin section slide from Rhosyfelin that precisely matches up with a thin section slide from the Stonehenge rhyolite debitage.  Rob and Richard, if you are reading this, and if you have such a "matching pair",  please send them along and I'll happily reproduce them.  Alternatively, you might wish to publish the slides in this strange thing called the "primary literature", in which case we look forward to reading the forthcoming article.

Sad as I am to bring this up again, I have to repeat that we seem to have a case of geological "over-interpretation" here -- which has, as we all know,  led to the committing of a multitude of sins by the archaeologists.


This is the figure published by Ixer and Bevins which shows the sampling points used in the collection of rhyolite samples.  As we can see, point 8 is near the tip of the spur and all the other points are on the SE flank of the ridge. It appears that no samples were taken in the original research programme from the NW face of the ridge, which has attracted so much attention........  No doubt other samples will have been collected from the rock face and analysed by now, and we look forward to reading about them in due course.


 

The Rhosyfelin "Quarry" -- is common sense breaking out?


One of the AerialCam images of the Rhosyfelin dig site, 2015.

It appears that common sense might be breaking out.  In the new edition of "British Archaeology" (March / April 2016), on pages 12-13, there is a letter from John Sorrell with the title "Where are the Mauls?" it is a response to the article by Mike Parker Pearson et al in the last issue of the magazine, which we have already discussed at length:
http://brian-mountainman.blogspot.co.uk/2015/12/the-new-britarch-article-by-mpp-et-al.html
It appears that we have at least one archaeologist who shares the view that there is no quarry at Rhosyfelin; probably the one who speaks out represents the views of a good many more......

I reproduce the letter below, with thanks to the magazine. It's worth looking at some of the points JS makes.

" I read the feature through straight away expecting to have my ideas reversed. But is seems as if pre-held ideas drive the interpretation." So it appears that John Sorrell, too, thinks that the quarry "discovery" is a non-event, based upon the over-zealous use of a ruling hypothesis.......

"As Craig Rhos-y-Felin is a perfect place to make a summer camp, some prehistoric activity should be expected."  Quite so -- exactly what Dyfed, John and I have been saying.

"Two important items were missing from the excavation:  mauls and chippings." Agreed.

"You would expect many tens (or hundreds) of mauls and huge amounts of chipped stone. Without these there is no case for quarrying."  Agreed.

"The occupation was dated to at least 300 years before bluestones appeared at Stonehenge: the statement that the stones loitered around in a local circle seems like special pleading."  Agreed.

 In making his "balancing" argument that the glacial transport hypothesis also has problems, JS says:
"It is not feasible that the “stone hunters” took every stone, and that they were all of the desired size and shape.  Somewhere there must be a moraine, now buried, from which the bluestones were obtained."   We will part company on this.  As I have said before, I think that the Stonehenge builders were looking for stones of some "desired size and shape" is not supported by the evidence.  The bluestones are a mottley collection of boulders, slabs and pillars that suggest that ALL the stones they could find, no matter what their characteristics might have been, were collected up, until there were no more left to gather.  And you do not need a "lost moraine" either.  As I have tried to explain many times on this blog, glacier snouts are not always marked by moraines.
 
"Although questioning the interpretation of these claims (by MPP and his team), I applaud the time and money going into this exercise."  I think I would disagree with that.  If vast budgets are being spent on archaeological research, on topics that are entirely fanciful with no secure underpinning in the form of preparatory work, God help us all.....

Where are the mauls?

Having had a long-time interest in the
origin of the Stonehenge bluestones,
I read the feature about quarries with
great enthusiasm (Jan/Feb 2016/146).
It is a story that always has had a
fascination for me.

I have come down on the side of the
glacial transport theory, having read
Brian John’s book (Books Nov/Dec
2009/109). Possessing a logic-driven
scientific mind, however, I am
perfectly willing to change my view
when confronted with sufficient
evidence. I read the feature through
straight away expecting to have my ideas
reversed. But is seems as if pre-held
ideas drive the interpretation.
As Craig Rhos-y-Felin is a perfect
place to make a summer camp, some
prehistoric activity should be expected.
The fireplace, orthostat and platform
are exactly what anyone living there
would do for themselves. There seems
to be no clear evidence that stones were
quarried from the rock face.
Why quarry at all when all around there
are shattered dolerite outcrops of all
sizes of stone ready to hand (look at
Carn Goedog)?

Two important items were missing from
the excavation:  mauls and chippings.  Stones
would most likely have been dressed on site to
reduce the weight for transport.  You
would expect many tens (or hundreds)
of mauls and huge amounts of chipped
stone. Without these there is no case
for quarrying. The “monolith” is a
product of glaciation; it is also, at 4m,
too big. The “threshold” stone is just
debris. The “lever point” stone is most
probably associated with household
living by the hut shelter occupants. The
“wedge” marks are more likely natural.
In my explorations over the Black
Mountains and Brecon Beacons of
many years, corners missing at fractures
in boulders are commonplace. The
occupation was dated to at least 300
years before bluestones appeared at
Stonehenge: the statement that the
stones loitered around in a local circle
seems like special pleading.

For balance, the major objection to
the glacial transport theory is the fact
that no relevant glacial debris has been
found anywhere between the Bristol
Avon area and the start of Salisbury
Plain. It is not feasible that the “stone
hunters” took every stone, and that they
were all of the desired size and shape.
Somewhere there must be a moraine,
now buried, from which the bluestones
were obtained. One day spotted dolerite
may turn up on a building site, but the
discovery will probably go unrecorded.

Although questioning the
interpretation of these claims, I
applaud the time and money going
into this exercise. It is only by finding
proof at the origin quarry or the glacial
moraine that the human transport
theory can be proved, so I look forward
to future excavations.

John Sorrell, Caerleon