THE BOOK
Some of the ideas discussed in this blog are published in my new book called "The Stonehenge Bluestones" -- available by post and through good bookshops everywhere. Bad bookshops might not have it....
To order, click
HERE

Friday, 14 December 2018

Scottish National Library map resource




Sadly, Where's the Path is discontinuing, after providing a fantastic service for people hunting for locations.  Apparently they can no longer afford the fees charged by Google for the provision of satellite imagery.  They always had problems with the OS too, being allowed only so much customer usage per day for copyright materials.

But the Scottish National Library rides to the rescue.  They are now providing a very similar service for free, using old OS maps (up to 6" scale) on the left and Bing / Microsoft satellite  imagery on the right.  It works well, as far as I can see -- and gives a grid reference for wherever the cursor happens to be.

https://maps.nls.uk/geo/explore/side-by-side/#zoom=10.993333333333334&lat=51.1888&lon=-2.8079&layers=161&right=BingHyb 

I have already used it quite a bit.

Stonehenge was built by cows




Silly season again. It would have been much more fun if it was about reindeer, but we can't always have what we wish for. Anyway, this is the latest big Stonehenge story, seized with glee by the media........ based on a new research paper in Antiquity (whose per reviewing procedures are, as we know, somewhat dodgy).

The article has nothing to do with Neolithic Britain, let alone Neolithic Stonehenge, but that hasn't stopped the Daily Mail and the Daily Telegraph from getting all excited.  As the Mail Online says:  Forget horsepower, Stonehenge was built with COW-power: Cattle that lived 8,000 years ago were used as 'animal engines' to lug around heavy objects for Neolithic people.  Wonderful stuff. Studied cattle foot bones from "Neolithic contexts"are assumed to have come from domesticated cattle, but that is by no means certain.  This is a matter for zoologists and bone experts, but I'm not sure how they would demonstrate that the effects on the bones were down to heavy pulling rather than being a consequence of these cattle living and moving about in a heavily-wooded  and mountainous environment.  I hope there are control studies involving "normal" or known wild cattle.......

But all good fun.........

    Antiquity, Volume 92, Issue 366
    December 2018 , pp. 1462-1477

    Gaining traction on cattle exploitation: zooarchaeological evidence from the Neolithic Western Balkans

    Jane S. Gaastra, Haskel J,. Greenfield and M. Vander Linden

    https://doi.org/10.15184/aqy.2018.178
    Published online: 11 December 2018
    https://www.cambridge.org/core/journals/antiquity/article/gaining-traction-on-cattle-exploitation-zooarchaeological-evidence-from-the-neolithic-western-balkans/4D7976886FE66AF19A956ADA45FAA376

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

    Abstract

    The study of the exploitation of animals for traction in prehistoric Europe has been linked to the ‘secondary products revolution’. Such an approach, however, leaves little scope for identification of the less specialised exploitation of animals for traction during the European Neolithic. This study presents zooarchaeological evidence—in the form of sub-pathological alterations to cattle foot bones—for the exploitation of cattle for the occasional pulling of heavy loads, or ‘light’ traction. The analysis and systematic comparison of material from 11 Neolithic sites in the Western Balkans (c. 6100–4500 cal BC) provides the earliest direct evidence for the use of cattle for such a purpose.

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

    Bos taurus metatarsal from KneĹževi Vinograd showing sub-pathological remodelling to the medial condyle resulting from traction usage. This bone was directly dated to 6015–5897 cal BC (photographs by J. Gaastra)

    https://www.arch.cam.ac.uk/gaining-traction-cattle-pulled-loads-2-000-years-earlier-than-previously-thought

    Press release:
    Gaining Traction: Cattle pulled loads 2,000 years earlier than previously thought
    Dec 12, 2018 12:00 PM

    Cattle were being used to pull loads as early as 6,000 BC according to new research, providing the earliest systematic evidence of animals being used as engines.

    In the study, published in Antiquity, archaeologists discovered that the bones in the feet of Neolithic cattle demonstrated distinctive wear patterns, indicative of exploitation as ‘animal engines’. If these practices can be proven elsewhere, it is expected to have major ramifications on our understanding of animal use in the Neolithic.

    Lead author Dr Jane Gaastra of UCL's Institute of Archaeology, said: “We have been able to provide the first conclusive evidence that farmers were using cattle for ‘traction’ almost 2,000 years earlier than the previous consensus date. There has only been one other foot sample from the Neolithic period found in Syria, but this was inconclusive.

    “The part of the Balkans where we found the bones was heavily forested in the Neolithic period, so chopping trees to create settlements would have required lot of person power. Cattle would therefore have been a vital asset helping to transport items such timber for housing.”

    The study, stemming from the EUROFARM project funded by the European Research Council, was conducted in the central and western Balkans and shows that the earliest European farmers were not simply using cattle as a source of meat or dairy products, but also as a source of propulsion. The findings indicate that traction in some form, and not necessarily through the use of ploughs or wagons, was present much earlier than previously thought.

    Most other studies have focused on the use of traction in much later periods, because it has often been conflated with ploughing or the use of carts which came much later.

    Co-author Dr Marc Vander Linden (University of Cambridge), said: “Until now it has generally been considered that traction only emerged by the 5th and 4th millennium BC, parallel to the introduction of the plough and the wheel, but our study demonstrates that this is not the case.

    “We reveal that when the wheel and the plough became available farmers were already experienced in using cattle for traction, and this could have facilitated the spread of these innovations.”

    While ploughing and cartage are forms of traction, they represent only two types of activity on a much broader spectrum of exploitative practices from specialised animals bred and used for regular work through to animals used for more occasional pulling activities, or for regular labour over a short number of years.

    The researchers investigated 12 cattle foot bone samples, from both male and female cattle (predominantly cows), from 11 Neolithic sites in the central and western Balkans (modern-day Croatia, Serbia, Romania and Bosnia-Herzegovina) spanning from 6,000 to 4,500 BC. The sites were open air settlements from multiple phases of the Neolithic.

    Foot bone was chosen as it is most affected by the stress of pulling and happens to be most commonly preserved in the archaeological record. In determining traction, the archaeologists were looking for extra bone growth in the inner part of the foot, as this is typically where the foot takes most of the load.

    The researchers hope to replicate the study in other European regions to determine the extent and duration of this form of traction. It is still unknown whether this form of traction is seen in only a selection of Neolithic groups or was a common practice across Europe. A firm understanding of the nature of early traction evidence in prehistoric Europe has significant implications for our knowledge of both management practices and the nature of labour and movement in prehistoric societies.

    Dr Gaastra concluded: “What is now needed is a wider comparative assessment of sub-pathological evidence for cattle traction in Neolithic (and post-Neolithic) Europe to determine both how widely this pattern of early traction was distributed and at what point we begin to see evidence for specialised heavy-traction animals.”

    The article is published online today in Antiquity. Gaastra, J., Greenfield, H., & Linden, M. (2018). Gaining traction on cattle exploitation: Zooarchaeological evidence from the Neolithic Western Balkans. Antiquity, 92(366), 1462-1477. doi:10.15184/aqy.2018.178

    The project is funded under the European Union’s Seventh Framework Programme, Social Science and Humanities Research Council of Canada and the University of Manitoba, the International Research and Exchanges Board of Washington, D.C. and the Fulbright-Hayes Program.

    Thursday, 13 December 2018

    More on Lake Maw (Somerset)




    In 2015 I posted these two spectacular images from Russell Glacier in West Greenland, showing partly-drained pro-glacial lakes.

    https://brian-mountainman.blogspot.com/2015/11/pro-glacial-lakes-russell-glacier-w.html

    I am now rather intrigued by the question:  could something similar have occurred in Somerset at the end of the Anglian Glaciation? (Or maybe at the beginning of it?  Remember that the biggest damming of Lake Teifi in West Wales is now thought to have occurred as the ice of the Irish Sea Glacier arrived -- not as it wasted away......)

    There are fantastic details on these images, including faint shoreline traces related to earlier water levels, the shoreline or washing limit created by the highest water stillstand, and the surprising survival of pre-lake landforms and sediments after submergence for an unknown length of time.  I'm also intrigued by the apparent lack of thick lacustrine deposits on the old lake bed.  What we see is a litter of erratic boulders which might have been emplaced by the glacier when it was in an expanded state -- pre-submergence -- or possible emplaced as dropstones from the abundant floating ice debris such as we see in the lower photo.

    Here is an interesting article:
    https://www.researchgate.net/publication/233495943_Glacier_advance_ice-marginal_lakes_and_routing_of_meltwater_and_sediment_Russell_Glacier_Greenland

    Most lakes of this type last for decades rather than centuries or millennia.  Details are given in this and other studies of ephemeral lakes relating to the short-lived oscillations of the ice edge, the routing of escaping meltwater across cols (where overflow channels may be created) and the sediments transported and deposited.  One particular focus of interest is the manner in which jokulhlaups (catastrophic drainage floods) occur -- but shoreline and lake bed features have received much less attention.



    Here is another image from West Greenland, showing pro-glacial lakes (with cloudy or sediment-rich water)  impounded as a result of the details of local topography.  Sometimes lakes are connected together in strings, and sometimes there are complex connections across submerged cols.  The retreating ice sheet edge is on the right.  Note the uplands with small glaciers and snowfields (with clearwater lakes) in the bottom left quadrant of the image.  We can pick up the main drainage routes leading from the pro-glacial lakes towards the coast  -- along these routes sediments are deposited and terraces may be formed.


    Back to Lake Maw.  On the map by Prof Nick Stephens he suggests that the Saalian / Anglian lake (if it really did exist) was impounded by an ice edge running along the middle of the Severn Estuary and located maybe somewhere near Flat Holm.  He suggests that most of the water in the lake came from melting on the ice front and from the impounded or trapped Severn River, submerging an extensive area across the Somerset Levels including the sites of Bridgwater and Burtle (where the famous Burtle Beds are located). He suggests that Cheddar and Weston Super Mare were not submerged, but if the water level was above 82m -- which it must have been, for water to flow over and through the Chard Gap -- then the lake must have been much more extensive on its northern flank. 

    Clearly, the nature of the sediments beneath the peat beds in the Somerset Levels are critical in the arguments about the existence of Lake Maw -- I'll take a look at that particular matter in another post. 



    A fine photo by Andy Russell of two of the Icelandic pro-glacial lakes held up against a hillside by very dirty ice -- and in the process of breaching the ice bridge that separates them.  Soon there will be just one lake here -- unless a catastrophic breakout occurs, in which case there will be a flood and the lake(s) may drain completely.

    Wednesday, 12 December 2018

    Intersecting outlet glaciers and glacial troughs, SE Greenland


    According to ancient tradition, I occasionally post something spectacular from the world of ice.  This is a Google Earth image of intersecting glaciers and glacial troughs in SE Greenland.  The biggest glacier is calving into a fjord at bottom left.  Glacier crossings of this type are very rare, since glacier systems generally try to maintain "brutalised" dendritic patterns which evacuate ice most efficiently.  This is all very difficult to work out, but it sure is interesting......

    Severn Estuary -- the glacial context


    The area shown in this map is crucial for our understanding of what happened during the Quaternary, and what the string of events might have been which resulted in the hypothesised glacial transport of the bluestones. The distribution of upland and lowland is crucial; during glacial episodes uplands tend to accumulate snowcaps or even small ice caps, and ice coming in from further away (ie ice from the Welsh ice cap of the ice of the Irish Sea Glacier) will always tend to fill depressions first and then spill out of them under the influence of the ice surface gradient and the dynamism of the ice mass.  Those who have, in the past, drawn "straight line" ice edges across this territory have portrayed situations that can never have happened.  In this sort of terrain, all ice edges must have been crenulated.  Where exactly they were located during the Anglian and the Devensisn glaciations (and maybe others as well) is still open to debate!

    The pattern or rivers shown here is inherited to some degree from pre-Pleistocene times,and some details will be down to diversions linked to ice action and meltwater overspills from pro-glacial lakes.

    I'm giving a lot of thought just now to that latter issue.  How and where might substantial bodies of meltwater been impounded?  Was there dead icei n the depressions, with a ribbon of meltwater between of the ice and the containing hillsides?  Were the water bodies joined together -- with a common surface level?  And was there a vast expanse of water across the Somerset Levels, with hill masses standing above the surface as islands?  If so, how much debris was introduced into this water body by the melting ice, and where are the resulting deposits?

    Interesting questions -- watch this space......

    Tuesday, 11 December 2018

    Mud, mud, glorious mud........


    There is something rather wonderful about tidal estuaries at low tide, when all the mud banks are exposed.  This particular scene is from Slebech Park, well up the Eastern Cleddau (also called Cleddua Ddu or "Black Cleddau")  and a few miles from Picton Point.

    There's not just mud here -- we can see in the bed of the creek that there are many boulders, and there are stony deposits exposed in the banks too.  One warm summers day, when I feel inclined, I might  check out whether any of these exposed deposits can truly be referred to as till........

    Poppit raised beach platform and overlying sediments

    I visited Poppit (at the mouth of the Teifi estuary) the other day, just to check out what might have changed since my last visit.

    The raised beach platform is as prominent as ever,  just round the corner from the main beach and most easily accessible at low tide.  But a lot of storm waves have been breaking onto the RB platform surface, and the overlying deposits are in something of a mess.  There has been a lot of slumping, and the sequence is in many places difficult to discern.

    Here are some images:

    Broken rock platform some metres above HWM but still affected by storm waves.  Much slumping here in the drift cliff, with some traces of the raised beach and much mixing of periglacial (brecciated bedrock) deposits and glacial deposits related to the Irish sea Glacier.

    At the base, c 1m of brecciated bedrock debris (head) representative of Early and Middle Devensian (?) periglacial conditions but also containing raised beach cobbles.  There is a clay-rich matrix, suggesting that this is a reworked deposit incorporated into the base of the overriding Irish Sea Glacier.  In the top part of the photo we see 1.2m of clay-rich Irish Sea till with apparent shear structures.  Above that, a 1m thick glacial deposit with a greater sand and gravel content, suggestive of flowtill deposition during ice wastage.  At the top of the section, a darker sandy deposit which might be sandloess.

    This section is a bit of a puzzle.  Bottom left -- the exposed surface of the RB platform, here composed of thin-bedded soft dark shales.Above that (at the base of the section) a 30 cm layer of convoluted brecciated  bedrock fragments incorporating larger local sandstone clasts and erratics.  Above that, up to 50 cms of brecciated sandstone and shale rubble held in a matrix of silt and clay.  Well-rounded RB cobbles are incorporated.  This is probably a basal glacial deposit incorporating periglacial and interglacial deposits.  Above that, up to 1m of relatively stone-free flow till (?) with more sandy materials towards the ground surface.  

    A good exposure of the raised beach platform overlain by the sequence of deposits as described above.


    I am puzzled by the layer of fine broken shale fragments at the base of the sequence.  Surely it cannot predate the raised beach?  At the moment I am inclined to think that it post-dates the beach sediments, which were protected near the innermost edge of the platform while the platform itself was subjected to severe periglacial conditions at a time of relatively low sea-level -- during the Early and Middle Devensian.

    More work needed here.......