Region 1: Inland Basin
There are several significant and spectacular examples of glacial features in the Inland Basin, though only New York and northern Pennsylvania were covered by the ice sheet. Glacial scour features in the Inland Basin include the Great Lakes and Finger Lakes. Glacial deposits include lake bottom sediments and drumlins, and moraines that drastically affected the drainage patterns of the region. Periglacial features, found in Pennsylvania and Maryland, include solifluction, patterned ground and boulder fields. Post-glacial erosion features include gorges where streams flowing over waterfalls into glacially cut basins (such as the Finger Lakes of central New York) eroded back up their valleys.
Region 2: Appalachian/Piedmont
Glacial scouring in the Appalachian/Piedmont region is evident in potholes, and the deepening and widening of lake basins such as Lake Champlain and glacial Lake Albany. Significant glacial deposits include the moraines that stretch across Pennsylvania and New Jersey. Periglacial features in the Appalachian/Piedmont region include numerous boulder fields, ice wedge casts and solifluction.
Region 3: Coastal Plain
Though the glaciers did not cover the Coastal Plain, several features of the region are closely linked to the most recent ice age. The northern Coastal Plain, including Long Island and Cape Cod, was formed entirely by the moraine deposits of the melting ice sheet. Periglacial features include deformation of the Coastal Plain sediments by frost action. Sea level changes caused by the forming and melting glaciers affected the Coastal Plain exposure and thus erosion and sedimentation.
Region 4: Exotic Terrane
The entire Exotic Terrane region was covered by the ice sheet during the most recent ice age, leaving a variety of glacial scour and deposit features. Scour features include the erosion of the highlands and cirques still seen on many New England peaks. Glacial deposits include moraines, wind deposits on drained lake bottoms, kettle lakes, drumlin fields, and eskers; marine clay deposits occur in Maine from the post-glacial rise of sea level. There are no periglacial features in the Exotic Terrane region because the whole area was under ice.