Saturday 8 June 2024

No Evidence of Glacial Transport of Newall's Boulder

** In this and other posts I have used the phrase Glacial Transport to mean the Glacial Transport of Welsh rocks to the Stonehenge Area, which is what the argument is about. That the boulders in the Pembrokeshire hills have been shaped there by the action of ice is a given and not in dispute.**

It seems there I have caused some confusion, so let me put it in simple direct language.

Here is rock found at Stonehenge. It is called Newall's boulder

Scientists have matched its chemistry to Craig Rhosyfelin, which is where it came from.

Some people say it was transported by a glacier which accounts for its shape and scratches.

The same people also say that rocks that are still at Craig Rhosyfelin "may or may not be "identical" with the Newall Boulder, but who cares anyway?"    

Photo from Dr John of a different boulder at Craig Rhosyfelin

But I care and ask, "If the boulders at Craig Rhosyfelin are identical to the one at Stonehenge doesn't that mean that how it got there didn't leave any signs on it? 

Yes, only if it can be shown that between leaving Craig Rhosyfelin and arriving at Stonehenge the boulder was shaped and scarred by a glacier can it be claimed to be evidence of glacial transport (from Wales to Wessex).

Another photo from Dr John of the boulder at Craig Rhosyfelin with a photo of Newall's boulder added, can you tell them apart?.

Thanks to Dr John for confirming there is no evidence of glacial transport of Newall's Boulder 

UPDATE: And again he confirms it:

There is no way you can look at one clast at Rhosyfelin and another at Stonehenge and say "This one has not been subjected to glacial transport and this one has".........

That having been said, there are certainly abundant glacially-transported clasts at Rhosyfelin that do display typical "diagnostic" surface features.

My new paper makes a very simple point: namely that the Newall Boulder displays a number of features that are characteristic of glacially transported clasts. I cannot understand why that should be such a problem for some people......

So boulders at Rhosyfelin have been shaped and scarred by Glacial Transport, so a boulder from there (pace Dr John "from near there" in his view) found at Stonehenge showing identical diagnostic features can't be said to prove that it was the journey to Wiltshire that shaped it.


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