Sanctuary wrote:
The excavations have also uncovered three holes where missing stones would have stood on the outer sarsen circle, evidence, it is believed, that the circle was indeed once complete.
The parch marks are in the area that hasn't been excavated (20th C ) but iirc has been geofizzed with negative results .I wonder if in the past someone official or otherwise dug in these three places looking for evidence of the 'missing' stones that would have made up the circle, then just back-filled them afterwards and that's what they've 'discovered'? Seems likely that someone would have checked this out donkeys years ago I would have thought but it never got recorded. Just a thought.
The negative marks suggest that there is something stopping access of nutrients and moisture for the grass which does not apply to surrounding grass .It could be closely packed chalk ,stones ,a stone etc btw , I'm not necessarily suggesting a sarsen stump .