Are these ceremonial? Some rock piles at the Hale Rerservation, Westwood MA

Went for a walk in the beautiful fall colors at a large conservation land down Rt 128 from here - the Hale Reservation in Westwood. But I did not see anything until we were leaving, when I thought I spotted something off to the side just before the trail to "Split Rock" and on the same side of the road as that trail. There were some rock piles in a gully next to the road but also some suspicious earth movement, ditching sorts of disturbances. I did not trust those first rock piles. But when I went in there and looked around I saw this one, slightly uphill, and it was much more covered with moss:I believe this is an effigy.

The trail to "Split Rock" goes in to the right of a stone wall. The "effigy" was on the far side of the wall. But continuing in along the trail you come, in a moment, to another rock pile next to a pine tree.
Is this ceremonial or were there practical activities going on here? Remains of boulder quarrying? I had already spent too long exploring earlier and had to go without giving this area on the way to "Split Rock" a thorough looking over. There were other traces in there and it would probably be worth exploring more but I am afraid it is a bit of a drive and, now, the prospect is too uncertain for a repeat visit. A pretty place.