THE BOOK
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....
To order, click
HERE

Sunday, 29 July 2012

Nonsense in support of a good cause


One can't possibly object to Adrian Green doing something energetic in support of a good cause, but I do object to the manner in which this wretched myth is simply perpetrated unquestioningly in a multitude of different ways.  Adrian Green -- if he is doing his job properly -- must know that the Stonehenge bluestones did not all come from the Preseli Mountains (let alone from one "quarry") and he must know that there are major doubts about the thesis that they were carried all the way by human beings -- but still he trots out this nonsense in the media.  I am not impressed.

Am I just being a grumpy old man? Maybe, but Adrian could perfectly well have done his cycle ride and publicised it in a more nuanced and honest fashion.

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

Museum director uses pedal power to highlight redevelopment campaign


Saturday 28th July 2012

http://www.salisburyjournal.co.uk/news/9843424.Museum_director_uses_pedal_power_to_highlight_redevelopment_campaign/

THE director of Salisbury and South Wiltshire Museum took on the Stonehenge Cycle Challenge to raise awareness of the museum’s redevelopment campaign. Adrian Green successfully completed the 200 mile bike ride from the source of the bluestones in South Wales to Stonehenge over three days. Mr Green wanted to raise awareness of the museum’s campaign to develop its new Archaeology of Wessex galleries which have just received a grant of £1.8m from the Heritage Lottery Fund. He said: “I have always been amazed that our ancestors managed to transport the bluestones from the Preseli Mountains to Stonehenge some 5,000 years ago.
“It was a challenge but only doing 60 to 70 miles a day is doable so it was also enjoyable.”

The new Archaeology of Wessex gallery will feature discoveries from Stonehenge and the surrounding landscape. The overall costs for the gallery are £2.4m, with the museum responsible for raising £600,000 to match the lottery grant. The museum has already raised £55,000 through donations and grants, but still needs to raise the outstanding £50,000 this year.

So far, Mr Green has raised more than £1,500 but he is looking for more donations.
To donate, visit http://justgiving.com/Adrian-Green4 or by send donations to the museum marked Stonehenge Cycle Challenge.

Wednesday, 25 July 2012

Water in some of its forms...

This is a wonderful photo, taken in one of the Greenland fjords.  Click to enlarge.  Enjoy!! 

The glacier that calved this particular berg was remarkably clean.  Most of the brash floating on the sea surface is probably debris from falls off the flanks of the iceberg.  There must have been a huge meltwater tunnel in the glacier originally.  This is all that is left of it....

Tuesday, 24 July 2012

Was Stonehenge built as a symbol of discord and protest?





I'm rather attracted by the strange story of Achill Henge, built in a remote boggy location on Achill Island in the west of Ireland by a rather rebellious individual called Joe McNamara.  Today Mr McNamara was refused permission to keep the structure, which was built originally in protest against something or other, without planning permission.  Some people love it, and others hate it-- but it is already something of a draw to tourists. 

What is it?  And what does it mean?  All very mysterious.  But it does occur to me that if Mr McNamara can put up something like this over a weekend in order to cock a snook at authority, and to demonstrate that he does not approve of the status quo, why not place the same interpretation on Stonehenge?  Forget all this nonsense about Stonehenge being a "symbol of unity" as proposed by MPP and his friends (see the Discovery report below) -- might it not have been built by some wild bunch of eccentrics who were fed up with the way the world was being run by their lords and masters, and who wanted to make a powerful protest in a way that would have the most long-lasting impact?  And maybe this explains why it was never finished -- they did it all without planning permission from the Bog Boss, and he slapped an enforcement order on them, with the full weight of the law, before the wonderful political protest could be completed?  A bunch of Neolithic hippies, sustained by endless orgies and BBQs, as confirmed by MPP himself.  Well, it does bear thinking about......

=============================

From the Irish Independent today:

Developer Joe McNamara’s ‘Achill-henge’ project refused by Bord Pleanala

http://www.independent.ie/business/irish/video-developer-joe-mcnamaras-achillhenge-project-refused-by-bord-pleanala-3179277.html

There's a video too.....


PLANS by former developer Joe McNamara to retain his controversial 'Achill-henge' project have been dashed after An Bord Plenala refused his retention application.
Mr McNamara had appealed Mayo County Council's decision that the structure required planning permission. He claimed the Stonehenge-like build was exempt from planning laws as it was an “ornamental garden”.
However, An Bord Pleanala has now ruled that the structure is not an exempted development. The body sided with Mayo County Council, ruling that the structure was a development in planning terms and required planning permission.
Mr McNamara constructed the structure, which is known locally as Achill-henge, over the course of one weekend at Pollagh on Achill Island last November. He had no planning permission for the build but had argued that it was exempt from planning laws.
In ruling against Mr McNamara's appeal, An Bord Pleanala said; “the scheme in question constitutes development by virtue of the substantial nature of the excavation and construction works involved.”
Mayo County Council said it would now consider the matter in the coming days.
Mayo County Council brought a High Court injunction against Mr McNamara's continued work at the site last December. The former developer was jailed for three nights at that time after he was found to be in contempt of a court order requiring him to cease working on the structure.
The High Court later ruled that An Bord Pleanala should make the final decision on the future of the site. However, the structure has proved a draw for tourists and many locals believe it unlikely that Mr McNamara will remove it.
The structure is 4.5 metres high and 30 metres in diameter.
Mr McNamara has previously described the structure as “a place of reflection”.

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

Stonehenge Built as Symbol of Unity

Analysis by Rossella Lorenzi 
Fri Jun 22, 2012
http://news.discovery.com/history/stonehenge-unify-britain-120622.html

Stonehenge was built as a monument to unify the peoples of Britain, researchers have concluded after 10 years of archaeological investigations.

Dismissing all previous theories, scientists working on the Stonehenge Riverside Project (SRP) believe the enigmatic stone circle was built as a grand act of union after a long period of conflict between east and west Britain.

Coming from southern England and from west Wales, the stones may have been used to represent the ancestors of some of Britain's earliest farming communities.

According study leader Mike Parker Pearson of the University of Sheffield, Britain's Neolithic people became increasingly unified during the monument's main construction around 3000 B.C. to 2500 B.C.

"There was a growing island-wide culture -- the same styles of houses, pottery and other material forms were used from Orkney to the south coast," Parker Pearson said.

"Stonehenge itself was a massive undertaking, requiring the labour of thousands to move stones from as far away as west Wales, shaping them and erecting them. Just the work itself, requiring everyone literally to pull together, would have been an act of unification," Parker Pearson said.

According to the researcher, who has detailed the new theory in the book Stonehenge: Exploring the Greatest Stone Age Mystery, the place in the county of Wiltshire where the iconic stones were erected was not chosen by chance.

On the contrary, it already had special significance for prehistoric Britons.

Parker Pearson and colleagues noticed that Stonehenge's solstice-aligned avenue sits upon a series of natural landforms which mark out the midsummer sunrise and midwinter sunset.

"When we stumbled across this extraordinary natural arrangement of the sun’s path being marked in the land, we realized that prehistoric people selected this place to build Stonehenge because of its pre-ordained significance," Parker Pearson said.

Basically, they would have seen the spot as nothing less than the "center of the world."

"This might explain why there are eight monuments in the Stonehenge area with solstitial alignments, a number unmatched anywhere else,” Parker Pearson said.

According to the researchers, the winter solstice was the more significant time of the year when Stonehenge was built 5,000-4,500 years ago.

"We can tell from ageing of the pig teeth that higher quantities of pork were eaten during midwinter at the nearby settlement of Durrington Walls, and most of the monuments in the Stonehenge area are aligned on sunrise and sunset at midwinter rather than midsummer," said Pearson.

The prehistoric monument has long baffled archaeologists, who have argued for decades over its original purpose, with two main theories taking shape in recent years: one was that it was a healing space, the other that it was a place of the dead.

Other theories suggested the great stone circle was used as a prehistoric observatory, a sun temple, and a temple of the ancient druids.

"The Stonehenge Riverside Project’s researchers have rejected all these possibilities after the largest programme of archaeological research ever mounted on this iconic monument," the researchers said in a statement.

Monday, 23 July 2012

The Grundtvigskirken rock face

This is the route followed by those mad climbers in 2010 when they climbed the whole 1300m up from the valley floor to reach the summit of Grundtvigskirken in Ofjord, East Greenland.  Apparently they needed 40 pitches on the way up.  Just thought you'd like to know.....

Banned bedtime reading.....



In TD's recent summary of the stone work at Stonehenge I found this reference:

Parker Pearson, M., Pollard, J., Richards, C., Schlee, D., Welham, K., Bevins, R.,
Chan, B., Doonan, R., Pike, A., Ixer, R., & Simmons, E., 2012, The Stones of
Stonehenge Project. Investigations in the Nyfer (Nevern) Valley in 2011. Sheffield:
Department of Archaeology, Sheffield University [Limited circulation printed report]

Can't find it anywhere.  Does anybody have it?  If so, please share.......

This is obviously a field report from the 2011 digs at Craig Rhosyfelin, Carn Goedog and elsewhere -- a summary of which was given in that rather infamous lecture evening in Newport last September.   That received some coverage on this blog, particularly during September 2011.  Just put "Rhosyfelin" into the search box and click.

The draft report may just be an internal document for circulation among the research participants, in which case it may be altered quite dramatically prior to eventual publication.

Latest Bluestone Research



Many thanks to Tim Darvill for this summary of Stonehenge work over the past few years.  reproduced below is the section relating to the stones -- and in particular, to the bluestone research undertaken in connection with various research projects.  I'm interested to see that TD's definition of "bluestone" is pretty close to mine: "non-local stone used in the construction and workings of Stonehenge and found at the site itself and in the wider landscape."  No mention of orthostats in that definition, which allows for fragments in the debitage / soil horizons to be included as bluestones -- but I would part company over the assumption that all bluestone fragments must have been used in the construction and working of the monument.

There is a long and comprehensive list of references -- recommended reading.

It's interesting that TD is admitting here to the wide variety of rock types (including some which have not been provenanced) turning up in the bluestone cellection -- and yet the obsession of the archaeology establishment with finding "quarries" appears to be undiminished.....

 --------------------------

Research activity in the Stonehenge Landscape 2005–2012

Timothy Darvill
Stonehenge and Avebury Revised Research Framework
6 July 2012

EXTRACT: 
 
Stone sourcing projects

Much new research has been carried out into the geological origins and source
outcrops of the various lithologies subsumed within the term ‘Bluestone’ as applied to
the non-local stone used in the construction and workings of Stonehenge and found
at the site itself and in the wider landscape. Stones  SH34 and SH35a have been
shown to be spotted dolerites (also known as Preselite) very similar to samples from
Carn Menyn while stones SH38 and SH40 are two different dacitic crystal-vitric-lithic
ash-flow tuffs and SH46 and SH48 are two different rhyolitic crystal-vitric-lithic ash-
flow tuffs (Ixer & Bevins 2011a). The stone type represented by SH48 was later
defined as rhyolite Group E (Rhyolite with visible feldspar phenocrysts) which is also
represented by two pieces of debitage from the 2008 excavations (Ixer & Bevins
2011a: 22). Group D rhyolites (rhyolitic tuffs with late albite-titanite-chlorite
intergrowths) are mainly confined to samples from the Stonehenge Cursus (see
below) and are of unknown source (Ixer & Bevins 2010: 7; 2011a: 21–22). Three
defined types of rhyolite (A-C) which are not represented amongst standing
Bluestones at Stonehenge but have been recognized as debitage from the 2008
excavations within Stonehenge, the Heel Stone area, several Aubrey Holes, the
Stonehenge Avenue, and the Stonehenge Cursus  all derive from a series of
outcrops at Craig Rhos-y-Felin near Pont Saeson on the north side of the Preseli
ridge in Pembrokeshire (Ixer & Bevins 2011b; Bevins et al. 2011; Anon. 2011d;
2012a; 2012b). This source area was the focus of archaeological attention in
Summer 2011 when evaluation trenches against the outcrop located a detached
columular bock and associated hammerstones (Parker Pearson et al. 2012).

A review of samples from the Altar Stone confirmed that it was a fine-to-medium
grained calcareous sandstone of the kind found in the Senni Beds of south Wales.
Four other pieces of sandstone from the Stonehenge Cursus, Stonehenge, Aubrey
Hole 1 and Aubrey Hole 5 share a common lithology as low-grade metasediments
and derive from a different source area, possibly from Lower Palaeozoic sandstone
beds (Ixer & Turner 2006).  

An examination of finds from the Cursus Field collected in 1947 and from
excavations by the SRP in 2006 and 2008 confirmed that much of the material could
be matched with samples from Stonehenge (identified as Groups A–D: Ixer &  Bevins
2011a; 2011b) but that some rhyolites could not be matched amongst existing
samples (Ixer & Bevins 2010; Ixer et al. forthcoming).

Paul Robinson (2007) reported the results of petrological studies of 21 stone items
from the Devizes Museum collections that were thin-sectioned by the Implement
Petrology Committee of the South Western Federation of Mueums and Art Galleries
in the late 1950s. This includes material from barrows in Wilsford, Shrewton, and
Winterbourne Stoke. An examination of spotted dolerite axeheads from southern
England suggests that some may have been made from pieces of Stonehenge rather
than introduced from more distant sources (Williams-Thorpe et al. 2006).  

A new study of jadeite axe-heads from Wiltshire has shown that the example said to
have derived from a barrow near Stonehenge and now in the Sailsbury and South
Wiltshire Museum (Accession number SSWM 28/59 (02919)) is of Alpine rock and is
used to define the ‘Durrington type’ with an almond or teardrop shaped outline and a
sharply pointed butt. The original findspot of the piece remains a matter of debate,
but a good case is made for derivation from the Knighton (Figheldean 27) long
barrow (Sheridan et al. 2010: 26 and fig. 7.2). [Contributions to SRF1 Research
Objectives 1, 5, 22]

Wednesday, 18 July 2012

Down memory lane...




Warning -- this has nothing to do with Stonehenge, bluestones, glaciers, erratics, MPP or fairies.

Down Memory Lane...... Thurs 19th July 1962 (fifty years to the day) we landed at Mestersvig, East Greenland, at the start of the OU East Greenland Expedition. Been looking at my old diaries -- I have reached the age where nostalgia becomes more important than anticipation. Happy days. We flew in one of these old things -- a DC3 hired from Flugfelag Islands. A wonderful aircraft -- no air hostess, no refreshments, and come to think of it, no seats either. They don't make them like that any longer.

Tuesday, 17 July 2012

That discordant glacier


Thanks to Chris Sugden for locating the image used in my earlier post.  He says the photo was taken from the air while flying from Knud Rasmussens Land across the southern coast of Scoresbysund, en route to the town on the other side of the sound.  This is the Volquart Boon Kyst, not far from Kap Brewster.  I should have guessed -- the bedded sediments shown in the photo are typical of this area.

So why do we find this extraordinary glacier tumbling down over a cliff onto the shore below?  Here are three photos from Google Earth:

On each of these we are zooming in closer and closer to the glacier which I think is the one in Chris's photo.  The top one of the three is an image taken when there was more snow about, but you can see the pointed headland to the west of the glacier more or less in the top centre of the image.

Along this coast there are many small, short, steep glaciers plunging down to the shore of the Sound.  They are all very strange!  The reason is that the ice shed (the glacial equivalent of a watershed) is almost at the coast here, rather than being set well inland.  Clearly what has happened is this:  there has been so much ice pouring out of the Scoresbysund fjord complex that the southern shore of the Sound has been overdeepened and eroded on a spectacular scale during the Pleistocene glaciations, leading to very dramatic landscape alteration -- the old landscape of Knud Rasmussens Land has seen the old valleys flowing north "chopped off" or eaten away by ice, leaving the old interfluve almost at the coastline.  

On the top photo you can see that the south-flowing glaciers (some quite large) have their catchment areas almost at the north coast of the peninsula.  Snow that collects on the steep and stepped north-facing slopes feeds much smaller and shorter glaciers -- they are too short and too young to have achieved very much glacial erosion, so they decant their ice over the coastal cliffs and into the sea, leaving people like me to gaze at them in wonderment....

Monday, 16 July 2012

Icehenge 2

Thanks to Pete G for bringing this site to our attention:

http://clonehenge.com/2009/01/22/icehenge-fairbankss-ephemeral-crystal-vision/

This page relates to a partial (ie no sarsen circle or part of it) reconstruction of Stonehenge, made of more than 100 blocks of ice in Fairbanks, Alaska, in 2007.  Machines were much in evidence!  There is also a link to a PDF which has great pictures of the project. Here are two of the images:


This is all very impressive, but it struck me on looking at the images that the model is strangely soulless and arid --there is too much geometrical precision and the edges are too sharp, and the trilithons and "bluestones" lack the variety and roughness which we have learned to love in the real thing.

Sunday, 15 July 2012

Icehenge

Bringing together the Stonehenge phenomenon and the recent posts about the work of glaciers, we give you ...... Icehenge!

This is an ice sculpture -- no doubt an ephemeral one -- created on the west coast of Greenland by a local artist.  Each "orthostat" is created by placing cut ice blocks (made of sea ice) one on top of another -- you can see the structures if you look carefully.  There is no reason why there shouldn't be a complete circle of ice pillars like these, and no reason why lintels cannot also be put in place.  It all comes down to motivation, time, money and equipment like heavy lifting gear.  Thick sea ice can easily support a JCB or similar hydraulic lifting gear -- but maybe that would spoil th artistic enterprise.  Sometimes artists can be very concerned that their "concept" is not despoiled by nasty modern gadgets....

Ice tongues -- the laws of physics still apply

These are three satellite images of ice tongues in Antarctica.  The top one shows Drygalski Ice Tongue, the middle one shows the Erebus Ice Tongue, and the third is at a location I haven't been able to identify.  These are very strange features -- essentially they are glaciers afloat, but not constrained by valley sides, so they just keep on pushing out from the coast, sometimes with the rate of forward progress faster than the rate of wastage or breakage, and sometimes being dramatically shortened if there is a major collision with a broken chunk of ice shelf or tabular berg.  Open water can have a similar effect, with tides and storm waves causing a fragmentation of the ice tongue tip, with huge tabular bergs then floating away.

These features seem to defy the laws of physics, since one would expect them simply to break up on reaching the coast, as is the case with most of the tidewater glaciers of Greenland and Alaska, for example.  The difference here is that there is a constraining medium -- sea ice or shelf ice which holds the glacier tongue in place.  So the glacier simply retains its shape, pushing out to sea in a relatively unchanged form although it is afloat and therefore vulnerable to breakup.

Such features are very rare in the northern hemisphere, although the Petermann Gletscher and other north Greenland glaciers do sometimes create tongues in situations where there is thick and persistent sea ice on the fringes of the Arctic Ocean.

The laws of physics still apply -- but don't ask me to try and explain in simple terms the strange serrated edges of the Erebus Ice Tongue...........








Danger -- ice at work

This spectacular high-definition photo shows the moment of impact when a huge boulder slides down the steep face of an ice-cored moraine into an ice-dammed or marginal lake.  This was taken on the flank of the Unterer Grindelwaldgletscher in the Alps, in May 2009.  The ice cored moraine face was 240m high, and during this collapse alone, 300,000 tonnes of debris collapsed into the lake, with high and destrucive waves causing a rearrangement of the outlines of the lake.  Lakes such as this can also drain catastrophically, and geomorphologists have learned that such environments, with deep and turbulent water, high glacier melt rates, and steep slopes of ice cored moraines are extremely dangerous.  People who walk on the crests of these ice cored moraines are putting themselves into danger -- and people (often unsuspecting tourists) are killed every year by collapses such as this.

Sometimes one has no option but to walk across such terrain, as my colleagues and I had to do in East Greenland in 1962, with very heavy packs on our backs.  Having crossed a wasting glacier and reached the safety of "solid ground" on the other side, there is just one emotion -- relief.....


This is another environment you definitely want to stay clear of..... hanging glaciers on the high flank of Mount Cook, South Island of New Zealand.  Features such as these are caused by very high snow accumulation rates and where friction on the rough bedrock surface is sufficient (for a while) to retain these enormous weights of snow and firn in position.  Some of these strange little glaciers may survive for decades, but many are very short lived, and during a warm summer, meltwater on the ice-rock interface may be sufficient to overcome the frictional drag -- resulting in a catastrophic collapse.  So avalanches are inevitable on slopes such as these.  Nevertheless, people still climb on them and ski on them in the spring, and people still get killed every year.......

These photos come from the great "Glaciers Online" web site.

Thursday, 12 July 2012

Stonehenge and Heaven's Henge



Got a message from Jon Morris relating to his Heaven's Henge ideas.  He says the first patents on the project are now out with video summaries:

http://heavenshenge.blogspot.co.uk/2012/06/understanding-patent-gb2486636-part-5.html

http://heavenshenge.blogspot.co.uk/2012/06/understanding-patent-gb2486409-part-4.html

http://heavenshenge.blogspot.co.uk/2012/06/system-operation-part-6.html 

If people want to discuss Jon's ideas on this blog, feel free...  but of course Jon's blog is also available for more detailed discussions.

Grundtvigskirken pinnacle, East Greenland

The view from the top -- Salewa 2010 expedition.  Bear Islands in the distance, to the left of the mad climbers
Photo: Greenland Tourism site
Photo: Greenland Tourism site
Photo: Gullisig
Photo: Tony Higgins
Photo: Rolf Strange

I've been fascinated by this extraordinary rock pinnacle near the shore of Ofjord, at the head of Scoresby Sund in East Greenland.  Some of the above photos were taken from the nearby Bear Islands.  The pinnacle is made from reddish granite and other crystalline rocks belonging to the Caledonian fold belt in this area.  The altitude of the summit is at 1,977m.  This is some doubt about who made the first ascent, but it might have been a British Army team in 1978.

The pinnacle is generally known as Grundtvigskirken (because of its similarity to a Danish church of that name) but there is some dispute about the name.  Sometimes it is given a German spelling.  Nowadays an Inuit name is preferred -- and there is some confusion with another peak in the area too, further along on the same ridge.......

What interests me in particular is the peak's mode of formation.  It is probably a last remnant of a ridge separating two glacial troughs -- this much is obvious from the Tony Higgins photo.  But the same photo also shows an extraordinary amount of scouring on the slopes beneath the pinnacle -- and this evidence of intensive ice erosion is matched by the evidence from the nearby Bear Islands.



Wednesday, 11 July 2012

What a wonderful world....

Red granite cliffs on the shore of Ofjord, East Greenland (Life on Thin Ice)
The sailing ship Hildur in Ofjord, East Greenland
Dendritgletscher, SE Greenland (Google Earth)
Lemaire Channel, Antarctic Peninsula
Winter landscape, SE Greenland (Knud Rasmussens Land)
Una's Tits -- a homage from Alex Cowan

Tuesday, 10 July 2012

A Discordant Glacier in Greenland


This is a truly amazing photo -- not because it's particularly beautiful, but because of what it shows.  I have never seen such a thing before.  Right in the middle of the photo there is a very active (heavily crevassed) glacier flowing between local ice caps and snowfields.  Nothing strange about that -- but look at the snout.  The ice suddenly plunges as an icefall over a steep precipice at the coast, piling up at the shoreline on the edge of a frozen sea.  This is a winter photo -- it would be interesting to see what this all looks like in the summer.

Normally when you see an icefall such as this, the ice is descending very rapidly from a tributary glacier at a higher level to a larger glacier flowing in a deeper trough, in which the ice surface is at a lower level.

What we have is a glacier in a hanging valley -- it is discordant because the floor of the trough occupied by the glacier is not very deep, and it is not at all graded to the floor of any glacier that might be a part of a larger ice drainage system.  Hanging valleys are almost always tributary valleys, left high and dry because the main valley, carrying a much greater volume of active ice, has been eroded down to a much lower level.  That is not the case here, for what we see is a coastal cliffline.

This might of course be within a fjord, in which case there would at one time have been a big glacier in occupation of the area on the right of the photo.

Are we looking at a "new" glacier here, carrying ice which previously flowed off in another direction, and now starting to excavate a trough?  That's a possibility, since strange confluences and abrupt changes of direction are not at all uncommon in East Greenland -- one of the things which makes this an endlessly fascinating area for glaciologists and glacial geomorphologists.

The image comes from one of Chris Sugden's YouTube videos.  If you see this post, Chris, can you give a precise location for the image?

Ice-carved Pinnacles at sea-level

Top: Rock pinnacles on the coast of SE Greenland (Chris Sugden).  Middle: Una's Tits and adjacent coastline in the Lamaire Channel, Antarctic Peninsula (Liam Quinn).  Bottom: Lofoten Islands, Norway (Mike Mallinger)

I was looking at one of Chris's Greenland films when I spotted a splendid image of rock pinnacles or buttresses apparently surrounded by sea water on the coast of SE Greenland, south of Scoresbysund.  It struck me that such features are comparatively rare at sea-level but quite common high in the mountains where a ridge between adjacent glaciers is gradually being whittled away by glacial processes and frost shattering.  (cf my posts of Torres del Paine etc).

What these features suggest is very active erosion by outlet glaciers to a level well below present sea-level.  That means either that relative sea-level was very low indeed at the time these features were created, or else that the ice streams responsible were so thick and dynamic that sea-level actually didn't matter very much -- with glaciers remaining grounded and eroding actively while other thinner glaciers might have had floating snouts.

I haven't examined the precise glacial history of the three locations mentioned above -- but what we have is very magnificent coastal scenery.......

By the way, in case anybody is offended / excited by the name of those twin peaks in Antarctica,  I can assure you that it's all official.  Here is the Wikipedia entry:

Una's Tits, also known as Cape Renard Towers, are two towers of basalt, each topped by a cap of ice, guarding the northern entrance to the Lemaire Channel on the Antarctic Peninsula. With the highest summit at 747 metres (2,451 ft), they are officially named "Una's Tits" and are identified as such on navigation charts. The peaks appear on a British Antarctic Territory stamp although they are not identified as such. The individual towers are referred to as "buttresses".

Una was a woman living in Stanley, Falkland Islands who was working for what is now the British Antarctic Survey.  The tallest tower has only been summited once; this was by a German team in 1999.

In case you wondered, Una's Tits are the ones on the left of the image, each one capped by a miniature ice cap.  If you want to look at other images, just do a search on Google.....





Monday, 9 July 2012

Erratics on ice

I was looking at some photos of glacial things the other day when I came across this one.  It shows landslide debris on the surface of a small glacier near Mont Blanc, in the French Alps.  You can see the scar left on the mountainside following the landslide, and also the disruption on the snowy surface right at the head of the glacier caused by thousands of tonnes of debris ploughing downslope.  The glacier will now carry this debris inexorably further and further away from its source -- and eventually, maybe after decades or centuries, it will be dumped as an erratic train or as a "cluster" of erratics like the Darwin Boulders of Tierra Del Fuego (see earlier posts on this topic -- use the search facility.) 

We have had much discussion on this blog about the Foothills Erratic Train of North America; it is thought that the material which makes up that "trail"of erratics was dumped following a series of "landslide events" high above the glacier surface near Jasper, Alberta.  The scene following each event will have been very much like that shown in the photo above.

Sunday, 8 July 2012

Aerial scouring, Bear Islands, Scoresby Sund


Another wonderful photo found on the web.  Fifty years ago, when I led the OU East Greenland Expedition with my friend David Sugden, we spent some of our time at Syd Kap, on the shore of inner Scoresby Sund, looking across at the Bear Islands.  This is a much closer view, similar to the one we had when we chugged back to Scoresbysund settlement in a little boat called Entalik.  This is classic aerial scouring terrain, with the rock surface moulded and smoothed by huge volumes of glacier ice coming out of various fjords into the head of a wider bay.  In the background there is an incredible rock pinnacle on the tip of a long spur between two fjords that held outlet glaciers from the Greenland Ice Sheet.

Ice in the Mountains


Had to share this one -- came across it on the "Glaciers Online" web site.  It's from the Nevado Paron area of the Andes.  Goodness knows what the annual precipitation is here -- there is a great deal of snow accumulating on these peaks and providing ice for the glacier in the foreground.  This is how snow accumulates in the uplands where there is jagged terrain (as in the younger mountain areas of the world) and where annual precipitation is high.

The Ixer File

There have been a number of enquiries recently on the blog about the whereabouts of the key papers dealing with the geology of the bluestones.  As a service to mankind -- since Rob is probably far too modest to do it himself -- here is a list of his published contributions on the Stonehenge / bluestone theme.  Rob -- if I have forgotten any, apologies -- please add them if you wish.

Bevins, Richard E. , Ixer, Rob A. , Webb, Peter C. , Watson, John S.  2012. Provenancing the rhyolitic and dacitic components of the stonehenge landscape bluestone lithology: New petrographical and geochemical evidence. , Journal of Archaeological Science, Volume 39, Issue 4, April 2012, Pages 1005–1019

RA Ixer & RE Bevins, 2011. Craig Rhos-Y-Felin, Pont Saeson is the dominant source of the Stonehenge rhyolitic ‘debitage’,  Archaeology in Wales 50 (2011), 21–31

RE Bevins, NJP Pearce, & RA Ixer. 2011.  “Stonehenge rhyolitic bluestone sources & the application of zircon chemistry as a new tool for provenancing rhyolitic lithics”, Journal of Archaeological Sciences 38 (2011), 605–22

Rob.A.Ixer and Richard E. Bevins. 2011. The detailed petrography of six orthostats from the bluestone circle, Stonehenge. Wiltshire Archaeological and Natural History Magazine, 104, 1-14

Rob.A.Ixer and Richard E. Bevins. 2010. The petrography, affinity and provenance of lithics from the Cursus Field, Stonehenge. Wiltshire Archaeological and Natural History Magazine, 103, 1-15

 R. Ixer and R Bevins.  2009. Important revision to Stonehenge bluestone theory.  British Archaeology, Nov / Dec 2009

Timothy Darvill, Geoffrey Wainwright, Kayt Armstrong and Rob Ixer 2008. Strumble-Preseli ancient communities and environment study (SPACES):  Sixth Report 2007-08. Archaeology in Wales. 48, 47-55.

T. Darvill, R.V. Davis, D.M.Evan, R.A. Ixer and G.Wainwright 2006. Strumble-Preseli ancient communities and environment study (SPACES): Fifth Report 2006. Archaeology in Wales. 46, 100-107.

R.A. Ixer and P.Turner. 2006. A detailed re-examination of the petrography of the Altar Stone and other non-sarsen sandstones from Stonehenge as a guide to their provenance. Wiltshire Archaeological and Natural History Magazine, 99, 1-15

R.S. Thorpe, O. Williams-Thorpe, D.G. Jenkins and J.S. Watson with contributions by R.A. Ixer and R.G. Thomas. 1991. The Geological Sources and Transport of the Bluestones of Stonehenge, Wiltshire, UK. Proceedings of the Prehistoric Society, 57, 103-157.

R. A. Ixer. 2003. Foundered or founded on rock - a future for Welsh provenance studies. In: "Towards a Research Agenda for Welsh Archaeology". C.S. Briggs (ed.). BAR British Series 343, 213 - 219.

R.A.Ixer. 1997. Detailed provenancing of the Stonehenge dolerites using reflected light petrography - a return to the light. In: Sinclair, A., Slater, E. and Gowlett, J., (eds), Archaeological Sciences 1995. Oxbow Monograph 64, 11-17.

R.A.Ixer 2007 Waiting by the river: Stonehenge and the Severn Estuary. Abstract. Stone artefacts as material and symbolic markers in cultural landscapes. An international perspective.Implement Petrology Group Meeting. York. September 2007

R.A.F. Ixer. 1996. The Bluestone Dolerites of Stonehenge - an opaque view. Abstract, Geology and Geochemistry in Archaeology. Mineralogical Society. Open University, April 1996

R. Ixer. 1997. Steep Holm "Bluestones". Current Archaeology 151, p. 279.

R. Ixer. 1997. Steep Holm "Bluestones". Steep Holm Newsletter. New Year 1997. pp 1 - 2.

Book reviews:  2009, 2010 The Bluestone Enigma. Stonehenge, Preseli and the Ice Age. Brian John.  British Archaeology 109, 55 and  Wiltshire Archaeological and Natural History Magazine

Saturday, 7 July 2012

Rob Ixer: Rock Provenancing in Wales

Thanks to Rob for reminding us of this article published in 2003 (I think) -- and dealing with some of the problems and opportunities of geological provenancing of stones in Wales and indeed beyond the Welsh borders. 

Foundered or founded on rock- a future for Welsh Provenance Studies 

R.A.Ixer
School of Earth Sciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT

http://goodprovenance.com/provenancing.htm


Here is a brief extract:

Altered dolerites are common and widely distributed in Wales with large outcrops, but many have sufficiently distinctive petrographical and geochemical properties that they can be distinguished from each other. The best-known example of Welsh lithic provenancing is of dolerites, namely the Preseli Spotted Dolerites that comprise many of the Stonehenge Bluestones. By using some petrography and trace element geochemistry, including extending an existing geochemical database, Thorpe et al (1991) were able to match (provenance) individual bluestones to a limited number of outcrops at Preseli. Later, Ixer (1996; 1997), using very detailed petrography, in both transmitted and reflected light, moderated by the geochemical work of Thorpe et al (1991), felt he was able to refine further the match, so identifying individual bluestones with specific outcrops. In both cases the workers were able to establish the geological provenance of the stones, namely where the rocks were formed. Provenancing in this example was straightforward but time consuming and quite costly, in the region of high hundreds to low thousands of pounds. The majority of the costs were spent in extending the geological database into a geoarchaelogical one dedicated to the provenancing problem.
 

Somewhat controversially Thorpe et al (1991) argued that the Stonehenge monolithics were exploited from glacial erratics on Salisbury Plain rather than taken directly from their Preseli outcrops, so suggesting that for the bluestones their archaeological and geological provenances are different. This distinction between the two sorts of provenance is as important as it is contentious and the current inability to be able to recognise the difference is a serious problem in lithic studies. In the case of the exploitation of primary, in situ raw materials the geological and archaeological provenances are identical to each other and to the geographical location of the resource. However, for naturally transported materials (secondary sources), be they gold grains from a gold placer deposit, flint and chert from Recent river or marine gravels, or lithics from glacially transported boulder clay the geological and archaeological sources have become separated. The archaeological provenance (the site of exploitation) has been moved from the geological provenance (original outcrop), sometimes, as in the case of gold grains, huge distances. It is probable that the significance of secondary sources has been undervalued in provenance studies, for example the role of glacial erratics as the raw materials for polished stone axes.
 

Although Briggs (1989) and more recently Williams-Thorpe et al (1999a) have argued that erratics could be a viable source for some polished stone axes most workers are happier with the concept of dissemination of axes from discrete factory sites.  

The full list of references can be found on the web page.  There's a full list of Rob's publications here:

http://www.rosiehardman.com/publications.htm

New Stonehenge Guide for the iPad



I'm happy to give a mention to this new interactive Stonehenge Guide for the iPad, written and published by Pete Glastonbury.  As bloggers will know, Pete has made many constructive comments on this blog over the years, and he has a great knowledge of the stones (strange and not so strange) which pop up here and there in the literature and in the landscape.  More details here:

http://itunes.apple.com/gb/book/stonehenge-guide/id542062034?mt=11

Friday, 6 July 2012

How many bluestone quarries are needed to make an archaeologist happy?

 Carn Meini.  When is a quarry not a quarry?

On several occasions on this blog I have tried to publish a comprehensive list of all of the erratic or foreign stone types found at Stonehenge and in the immediate environs.  I came up with a list of more than 30 rock types, which means more than 30 different provenances.....

Myris has recently reminded us that MPP is off hunting for Neolithic quarries again, and that he has had detailed discussions with the geologists as to where these might be.  I would argue that that is a total waste of time and taxpayer's money, but I doubt that he will be deterred.  So how many quarries are needed to satisfy an archaeologist who lives with the utter conviction that glacier ice had nothing to do with Stonehenge?  I would say that we need at least 30 of them, since we do not just have to explain the presence of orthostats but also the presence of "debitage" (such as the debitage traced to Rhosyfelin) and other lumps of stone of various shapes and sizes.  Rob would argue that we should dismiss all of this ancillary or incidental material and concentrate on the orthostats -- and he argues on that basis that all we need to find would be about ten quarries.  I part company with him on that -- debris and foreign stones MUST be accounted for, whether they have been carried into the area by glacier ice, human beings or even machines involved in road-building works.  (I have the same problem on Pembrokeshire beaches, trying to work out what might have been carried by ice and what might be dumped ship's ballast from the grand old days of sail.....)

So -- ten quarries, or thirty, or somewhere in between?  And what are the features on the ground that we need to be able to identify in order to call a rocky outcrop a Neolithic quarry?  We have had much discussion on this site about THE bluestone quarry at Carn Meini -- now, from what Rob is suggesting, Rhosyfelin is likely to be given similar star treatment.  First will come a picnic site on the river bank -- then how about an interpretation panel and maybe a tasteful snack bar?

Here is the bluestone list published on this blog in 2010.  It is as reliable as I can make it -- it it has any errors, please let me know.  I will adapt and add notes as necessary.  With a suitable input for geologists, I hope it can be refined to the point of becoming reliable and maybe even definitive.

Known Stonehenge Bluestone Types

1.  Unspotted dolerite ---- monoliths  45 and 62.  Carn Ddafad-las?

2,  Spotted dolerite -- densely spotted.  Monolith 42  -- Carnbreseb? 43?

3.  Boles Barrow dolerite -- spotted?  But similar to stones 44 and 45? From Carnmeini / Carngyfrwy area?

4.  Rhyolite  -- stones 38, 40, ignimbrite character.  Ash-flow tuffs (dacitic). Not Carnalw ? May be from different sources?

5.  Rhyolite --  stones 46 and 48, rhyolitic ash-flow tuffs.  Carnalw area?  Same source?

6.  Rhyolite fragment from a different source from the above types

7.  Laminated calcareous ash -- stumps 40c, 33f,  41d

8.  Altered volcanic ash -- stump 32c, 33e?

9.  Rhyolite -- another type -- stump 32e.  Related to Pont Saeson samples? (Note added: This is the foliated rhyolite described from Rhosyfelin by Ixer and Bevins -- but the link with stump 32e is speculative, being based on photographic rather than rock sampling evidence.)

10.  Micaceous sandstone -- stumps 42c, 40g (Palaeozoic -- South Wales origin?)

11.  Rhyolite -- lava -- stone 46

12.  Rhyolite -- flinty blue -- different lava?  stone 48

13.  Spotted dolerite with whitish spots --stones 33, 65, 68, stump 70a?, stump 71?, 72

14.  Spotted dolerite with few spots -- stone 31, 66?

15.  Spotted dolerite with pinkish spots -- stones 150, 32, 34, 35A, 35B (one stone), 39 (?), 47, 49, 64, 67, 69, 70

16. Spotted dolerite -- moderate spots -- stone 37, 61, 61a?

17.  Unspotted dolerite -- stone 44 -- different from stones 45 and 62

18.  Very fine-grained unspotted dolerite -- stone 62

19.  Silurian sandstone -- Cursus -- fragments

20.  Devonian sandstone -- Altar Stone -- Devonian Senni Beds -- Carmarthenshire or Powys

21.  Sarsen sandstones -- various types -- packing stones and mauls

22.  Jurassic oolitic ragstone -- Chilmark?

23.  Jurassic glauconitic sandstone -- Upper Greensand?

24.  Gritstone unspecified fragments (Maskelyne, Judd)

25.  Quartzite unspecified fragments (Maskelyne, Judd)

26.  Greywacke unspecified fragments (Maskelyne, Judd)

27.  Granidiorite -- Amesbury long barrow 39

28.  Quartz diorite -- ditto

29.  Hornblende diorite -- ditto

30  Flinty rhyolite -- fragments from Pont Saeson (Note:  different from the Rhosyfelin samples?)

31.  Rhyolite fragments -- with titanite-albite intergrowths (source unknown)

Thursday, 5 July 2012

Where were the bluestone erratics dumped?


 

Two maps previously published on this blog, showing the ice limits proposed in various publications by other authors.


I gather from one of our little blogging community (for which many thanks) that this is what MPP says about the glacial theory in his new book:

"John thinks that bluestone erratics could have been dumped south of Bristol in the area around Glastonbury where perhaps some remain to be found, buried beneath the peat. Even if this hypothesis were correct, Neolithic people would have had to move the stones forty  miles from Glastonbury, or anywhere else in the Severn Valley, to Stonehenge."

I'm sure that this is a quote taken out of context, and that there is much more in the way of detailed discussion and analysis in the book, but just for the record here are a few brief points:

1.  I do indeed think that bluestone erratics could have been dumped south of Bristol,  but I also think they could have been dumped south of the Mendips, across the Somerset Levels, in the Glastonbury area, or up against the chalk escarpment, or even on the western parts of Salisbury Plain.  All of that would have been perfectly feasible from a glaciological point of view.  I am not THAT keen on Glastonbury as the dumping ground for bluestones from the west -- although I admit to being rather taken by the romantic idea of these two great iconic locations being connected by bluestones!  As readers of this blog will know, I have played around with various ideas which are sensible when we look at the field evidence of glaciation in the South-West.  But as ever, we need more evidence on the ground......

2.  Yes, wherever the stones were collected from, they would have been moved over a greater or lesser distance by the stone gatherers.  I have never denied that -- and as readers of the blog will know, my current theory for bluestone transport is in the nature of a "hybrid hypothesis" involving glacier ice (initially) and human agency (subsequently).

3.  The Severn Valley?  MPP has got his geography a bit wrong here.  I have never suggested that the bluestones might have come from the Severn Valley -- the Severn Valley carried material broadly southward along the eastern edge of the Welsh uplands, and the ice affecting the area might have incorporated north or mid-Wales erratics, but not erratics from west Wales.

Monday, 2 July 2012

Another review for "The Bluestone Enigma"


Thanks to Chris Lovegrove for drawing my attention to his new review.

30/06/2012
http://calmgrove.wordpress.com/2012/06/30/bluestones/#comment-61

Stonehenge’s mythic history

Brian John
The Bluestone Enigma: Stonehenge, Preseli and the Ice Age

Greencroft Books 2008

Ancient man didn’t transport stones hundreds of miles. And nor did Merlin.

Brian John, who lives in Pembrokeshire (where much of this study is set), has had a long interest in this whole subject area. A Geography graduate of Jesus College, Oxford, he went on to obtain a D Phil there for a study of the Ice Age in Wales. Among other occupations he was a field scientist in Antarctica and a Geography Lecturer in Durham University, and is currently a publisher and the author of a number of articles, university texts, walking guides, coffee table glossies, tourist guides, titles on local folklore and traditions, plus books from popular science to local jokes. His credentials are self-evident when it comes to discussing Stonehenge.

One of the strongest modern myths about Stonehenge to have taken root is that the less monumental but no less impressive so-called bluestones were physically brought by prehistoric peoples from the Preseli Hills in south-west Wales to Wiltshire. The second strongest modern myth is that the whole saga was somehow remembered over a hundred or more generations to be documented by Geoffrey of Monmouth in the 12th century as a feat of Merlin. In this self-published title Dr John examines these and other myths and finds them wanting in terms of echoing reality.

His key points include the fact that not only do the bluestones derive from at least fifteen different locales in West and South Wales (not just the Preselis), there is no evidence at all for any stone-collecting expeditions from as far afield as this, let alone cultural links between Wessex and West Wales.

He deduces that bluestones were present “on or near” Salisbury Plain at least a millennium before Stonehenge was commenced, and were not especially selected for their quality, their supposed magical significance or healing properties (he points out that many of the Stonehenge bluestones are defective, and that it is pure speculation that the builders saw a reflection of the night sky in them or saw them as having healing powers). How did the stones get to Wessex? The author’s expertise in geomorphology allows him to discourse authoritatively on how Welsh stones could have been brought by the great Irish Sea glacier as far east as Bath, the Mendips and Glastonbury (though uncertainty still exists whether it reached as far east as Salisbury Plain).

If there was no Grand Designs project to transport the stones from the Preselis (and the author effectively demolishes the case for prehistoric technology being up to the task) then it follows that the famous tale of Merlin moving stones from Ireland to Wessex, much beloved by New Age mystics, is not a reflection of historical reality. Does it not seem more likely that this is Geoffrey of Monmouth’s elaboration of the familiar folktale motif of a demigod or the Devil himself (Geoffrey claims Merlin was the son of the Devil after all) moving landscape features around at will?

While The Bluestone Enigma doesn’t come up with definitive answers to tell us the final story of the bluestones, it does put paid to the imaginative but impractical theories of certain archaeologists and writers of popular accounts of Stonehenge. Whether it will silence the myth-makers is another matter however.

Chris Lovegrove

Updates on Brian John’s research are posted here: http://brian-mountainman.blogspot.co.uk/