Before revision: As plateaus are dissected by the headward erosion and incision of river and stream courses and the retreat of their bounding escarpments, plateaus are fragmented into tablelands of smaller and smaller extent known as mesas, buttes, or rock cities .
After revision: As plateaus are dissected by the headward erosion and incision of river and stream courses and the retreat of their bounding escarpments, plateaus are fragmented into tablelands of smaller and smaller extent known as mesas, buttes, or pinnacles .