Colby students peer out from behind a particularly large moraine boulder.
Kettles result from melting of blocks of buried glacial ice.
The delta surface is one of the most extensive flat areas in Maine. The front of the delta bears a wave-cut bench that reveals enormous boulders from an underlying moraine. Giant foreset beds are exposed in this old sand pit, shown in 1995. Delta foreset sands interfinger with the bottomset beds of the Presumpscot Formation. Periodic burning keeps weeds down in the commercial blueberry areas.