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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....
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Wednesday, 6 August 2025

The Newall Boulder -- not just weathered, but eroded



In one media piece after another, over the past couple of weeks, on the matter of the Newall Boulder, we have seen statements like this:

Prof Bevins and his team said most of the characteristics cited "could be simply generated by surface weathering".

.........the new research asserts that surface markings previously believed to be glacial abrasion are more likely the result of natural weathering or ancient human handling.

.......wear patterns cited in previous studies as resulting from glacial movement could have actually been caused by natural weathering.

Bevins and colleagues suggest the marks on the stones were not signs of abrasion by the glacier, but were made by human hands coupled with general surface weathering instead.

This is all very weird, and suggests that assorted senior academics do not know the difference between weathering and erosion.  Very strange, since this is one of the things that a student of O level Geography or Geology would be expected to know.  For the record, "weathering" is the term used to cover the in situ breakdown of rock surfaces as a result of physical and chemical processes.  In contrast "erosion" incorporates the movement or transport of material away from its original location, and the use of tools (sand, gravel and larger clasts) in lowering the rock surface.  There are many erosive processes, but abrasion is one of the most important, involving the grinding away of a surface of relatively soft material by ongoing contact with relatively harder "tools".  We might call it the sandpaper effect.  



I cannot imagine why they thought this necessary, but the eleven authors of the recent Newall Boulder tirade appear to be determined to avoid any mention of erosion in their press releases and statements to the media.  So they pretend that the surface of the boulder incorporates some structural elements (describing it as a "joint block" on which all the surfaces coincide with fracture planes) but where the detailed surface characteristics are the result simply of surface weathering.

This is  a serious misrepresentation of the situation. I stand by everything I said in my detailed analysis of the boulder surface.  One face is a fault-controlled feature with slickensides, and some of the other distinct facets may also coincide with joints or other internal weaknesses, but they are clearly abraded, and cannot be explained away as the results of weathering porocesses alone. There are also percussion fractures and fracture scars, some of which might be related to human interference.  The chatter marks are best explained by reference to subglacial processes during ice transport.  There are some slight scratches, but I have refrained from describing them as genuine striations or grooves.  In my paper I describe the weathering features as well.  They are quite complex, but quite distinct from the features associated with erosional history.

For those who seem to be ill-informed on these matters, I can recommend a useful tome, the cover of which I reproduce below.  Other texts are also available.



The literature:

John, B. S. 2024: A bluestone boulder at Stonehenge: implications for the glacial transport theory,
E&G Quaternary Sci. Journal 73, 117–134,

https://doi.org/10.5194/egqsj-73-117-2024

Bevins, R. E., Ixer, R. A., Pearce, N. G., Scourse, J., and Daw, T. 2023: Lithological description and provenancing of a collection of  bluestones from excavations at Stonehenge by William Hawley
in 1924 with implications for the human versus ice transport debate of the monument’s bluestone megaliths, Geoarchaeology, 38, 771–785, 

Richard E. Bevins, Nick J.G. Pearce, Rob A. Ixer, James Scourse, Tim Daw, Mike Parker Pearson, Mike Pitts, David Field, Duncan Pirrie, Ian Saunders, Matthew Power, 2025.  The enigmatic ‘Newall boulder’ excavated at Stonehenge in 1924: New data and correcting the record,
Journal of Archaeological Science: Reports, Volume 66, 2025, 105303,
ISSN 2352-409X,


Victorian gifts: new insights into the Stonehenge bluestones
Rob Ixer, Richard Bevins, Nick Pearce, and David Dawson explain more. 2022.
CURRENT ARCHAEOLOGY, AUGUST 29, 2022, 5 pp

4 comments:

Tony Hinchliffe said...

What a phenomenal list of references, Brian. I would just add that, when, just over 3 years ago, in 2022, in one of your Posts on the Newall Boulder you assiduously set down the comments you had received on your boulder photographs from many geologists and glacial geomorphologists you'd consulted. I think I'm right in saying, am I not, that ALL consulted agreed with you that the Newall Bouldet, excavated at Stonehenge, had indeed been eroded?

Tony Hinchliffe said...

No less than TWELVE senior glacial geomorphologists agreed with Brian, on examination of his photographs, that the 1924 Stonehenge boulder excavated by Newall had indeed been glacial eroded. Go to:- "A glacial coast from Stonehenge: Newall's Erratic Boulder" dated July 2nd 2022. Yet we get this clamour of denial from the human transportation fraternity......Methinks they doth protest too much.

Tony Hinchliffe said...

Apologies for the virtual duplication of Posts - my gizmo implied that the 1st Post hadn't been sent. P.S. the 2nd Post should read "a glacial CLAST"

BRIAN JOHN said...

Yes, I sought the views of 12 professors in 2022, and 11 of them thought that the Newall Boulder showed signs of glacial erosion and transport. The other one thought it was probably subjected to shaping processes in a fluvioglavciual environment. So there we are then........