If there are two things the glaciers you mentioned a few posts back would accomplish it would be creating cracks that would expose things to water and oxygen, and also expose the resulting heaps to loads and loads of water. This is how stones found in glacial deposits look like: https://sv.wikipedia.org/wiki/Rullstens%C3%A5s#/media/Fil:Ru...
Note how rounded all the stones are. And the stones that are there are generally speaking a LOT more resilient than any variant of limestone will ever be (including concrete).
Note how rounded all the stones are. And the stones that are there are generally speaking a LOT more resilient than any variant of limestone will ever be (including concrete).