Ring of Brodgar again

 The ring of Brodgar, looking NW.  The supposed quarry for the stones used here is away in the distance, at a location referred to as Vestra Fiold.

Here are the links to our previous discussions:

http://brian-mountainman.blogspot.co.uk/2011/11/vestrafiold-quarry-orkney.html

http://brian-mountainman.blogspot.co.uk/search?q=Ring+of+Brodgar

I've now been in correspondence with Dr John Flett Brown, a geologist who knows the area well.  He says this:

"The standing stones at Brodgar and Stenness cannot be erratics or derived from the cutting of the trench.  Structural strength would not allow transport as bedload in ice sheet. Weathering pattern shows two stages one side while in the quarry area and both sides while in present location. Folk
Memory and place names chart the route of the stones from undoubted source at Vestra Fiold downhill all the way to Loch and beyond."

With all due respect to John, I defer to nobody and disagree with him when he says: "The standing stones at Brodgar and Stenness cannot be erratics or derived from the cutting of the trench."  They could indeed -- and if John wishes to support his statement, let's see the colour of his evidence.  Allan Hall suggests there are seven different rock types represented in the standing stones group -- and so they cannot all have come from one quarry.

Then he says:  "Structural strength would not allow transport as bedload in ice sheet."  Again I disagree.  The stones are indeed flat, thin and fragile, but their survival in an ice sheet depends upon all sorts of factors -- including the mode of transport and the distance travelled.  So let's hear the arguments......

Then he says: "Weathering pattern shows two stages one side while in the quarry area and both sides while in present location."  Now this gets seriously interesting, and potentially much more persuasive.  Weathering evidence, if carefully collected and documented, might well convince me that the stones might have been quarried -- but I need more than a statement.  I need the evidence -- and I have not seen it anywhere in print.  So John -- or anybody else -- please let us have it properly documented.

Then he says:  "Folk Memory and place names chart the route of the stones from undoubted source at Vestra Fiold downhill all the way to Loch and beyond."  I don't accept that folk memories can go back as far as the Neolithic, even on Orkney -- and I'd like to see the evidence in support of that statement -- and what is the place name evidence?

The stones have an "undoubted source at Vestra Fiold........"  Again, let's see the colour of the evidence. 

I'm not prepared just to accept the definitive statements of geologists any more than I am when considering the definitive statements of archaeologists.......