Some of the ideas discussed in this blog are published in my new book called "The Stonehenge Bluestones" -- due for publication on June 1st 2018. After that, it will be available by post and through good bookshops everywhere. Bad bookshops might not have it....
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Monday, 31 December 2012

MPP on the glacial transport theory

On p 268 of his book Prof Marker Pearson gets on to the glacial transport hypothesis.  (I'm happy to accept that it still is a hypothesis, in the absence of any killer facts....)

He starts off by referring to Judd and Kellaway and their ideas about glaciation -- although he can't resist throwing in Kellaway's rather extreme Pliocene glaciation idea, just to show what a nutter he is.  (James Scourse did exactly the same thing in the big Stonehenge book a few years ago;  it's known in the trade as the Aunt Sally syndrome.... you put up some rubbish just in order to knock it down.)  Anyway, MPP then refers to the evidence for glaciation,  somewhat selectively, and appears convinced by Chris Green's conclusion that since he didn't find any "glacially derived material" in certain of the river terraces on Salisbury Plain, the chalklands of Wiltshire cannot ever have been glaciated.  Things are not quite so simple, as I have pointed out many times.

He refers to Chris Clark and myself as glaciologists, which we are not.  He then cites Chris as saying that there is a "distinct lack of any evidence" that the ice advanced into south-west England at all.  That, to put it mildly, is absolute nonsense -- as I have said many times before.  Does MPP not do any reading for himself on glaciology or glacial geomorphology?  There is ABUNDANT evidence that the ice of the Irish Sea Glacier crossed the Bristol Channel -- he only needs to read my book called "The Bluestone Enigma" to see some of that evidence, accompanied by references and photographs.  There are plenty of other tomes too.  He then throws in the red herring of the last glaciation, claiming rather disingenuously that glacier ice did not extend beyond Wales around 27,000 years ago.  The glacial maximum was well after that, and the Devensian ice really did extend well beyond Wales, having been shown by James Scourse and others to have reached the Scilly Isles and well into the Bristol Channel.  In any case, the real issue is not how the Devensian Irish Sea Ice Sheet behaved, but how the Anglian ice sheet behaved, maybe 450,000 years ago.  And when we look at THAT ice sheet, the glacial geomorphology community is in agreement that the ice extended AT LEAST as far east as Bathampton Down, the Mendips and the Somerset Levels.  MPP should at least have the good grace to accept that a mottley collection of chips, stones, boulders and pillars (of all shapes and sizes) made of around 30 different rock types, all from the west or north-west, just MIGHT constitute evidence of glaciation on Salisbury Plain..........

By the way, on p 285 of the book MPP publishes a nonsense glacial map -- which seems to be based on one of the maps in a paper by Chris Clark and others.  It purports to represent the BIIS about 27,000 years ago, whereas it is labelled in the original paper as having a date of 23,000 years ago.  The glacial maximum was later still, around 20,000 years ago.  Furthermore, the strange glacial lobe projecting into the Celtic Sea is deemed by glaciologists as being inherently unlikely, given what we know of the laws of ice physics.  In this citation, as in others, a bit more care and a bit less haste might have been appropriate........  and in particular, if he wanted to use a map, MPP should have used a map showing ANGLIAN ice limits as far as we know them, more or less on the lines of the maps at the head of this post.

1 comment:

Anonymous said...

Dear Gandalf, my memory is rather hazy. Could you remind us all if MPP found the buckets they transported all the small crap in or not?

As an aside; and a possible nice New Years Present (we shall be in touch soon). Over the last year or ten, We have measured some nice decorative ripply patterns in some of our hobbit holes,similar to the pretty ones you photographed in your ice palace in Sweden; Although ours could be pre-mesolithic artex. These can be used to calculate palaeo flood discharges +/-10percent.

Our humble abode was flooded during the Anglian period. The calculated discharge for the larger overprinted ripples is a fair match for the average spring flood discharge shown in our bloody water bill. approx 7000 l/s (typical Interglacial flood discharge?);No foreign migrations for us this year!!!.

The smaller ripply patterns that overprint the interglacial ones, demonstrate a two order increase in discharge?

The insurance premiums are getting a bit steep,so might you with your mastery of "magic" care to hazard a guess as to the source of all this extra water.

My Missus reckons its Orc's Piss.

Happy new year