Possible damage model for quake vs buildings: a building can cancel some volume of terrain deformation by instead losing hitpoints (and spawning an appropriate number of dust clouds). If damage is too large, the building explodes (but still limits the terraform effect).
Gauss on a spire hit with a Quake now takes massive damage, but maintains the spire as long as it is alive. Gauss on flat land hit with a Quake takes no damage. A Gauss that failed to tank this damage blows up and remains sitting on a half-flattened ruin of a spire.
Pickets on a cliff edge just blow up in hilarious quantities.