Physiographic Regions Of The Lower 48 United States: A Geomorphic And Topographic Guide.pdf

# Physiographic Regions of the Lower 48 United States

This map presents a composite view of the United States' physiographic regions, categorized by Nevin Fenneman's (1946) three-tiered system. These regions are defined based on terrain texture, rock type, and geological history:

## Laurentian Upland:
1. Superior Upland
2. Atlantic Plain
3. Continental Shelf (not shown on the map)

## Interior Highlands:
- Ozark Plateaus: Springfield-Salem, Boston Mountains
- Ouachita Province: Arkansas Valley

## Coastal Plains:
- Embayed, Sea Island, Floridian, East Gulf, Mississippi Alluvial, West Gulf sections.

## Appalachian Highlands:
1. Piedmont Province: Piedmont Upland and Lowlands
2. Blue Ridge Province: Northern and Southern sections
3. Valley and Ridge Province: Tennessee, Middle, Hudson Valley sections
4. St. Lawrence Valley: Champlain and Northern sections (not shown)
5. Appalachian Plateaus Province: Mohawk, Catskill, Southern New York, Allegheny Mountain, Kanawha, Cumberland Plateau, and Cumberland Mountain sections.
6. New England Province: Seaboard Lowland, New England Upland, White Mountain, Green Mountain, and Taconic sections.
7. Adirondack Province

## Interior Plains:
- Interior Low Plateaus: Highland Rim, Lexington Plain, Nashville Basin
- Central Lowland: Eastern and Western Lake sections, Wisconsin Driftless, Till Plains

## Rocky Mountain System:
16-22. Various mountain ranges and plateaus, including Southern, Middle, and Northern Rocky Mountains; Columbia Plateau; Colorado Plateaus; and Basin and Range province.

## Pacific Mountain System:
23-25. Cascade-Sierra Mountains, Pacific Border province (Puget Trough, Olympic Mountains, etc.), and Lower California province.

The map provides a detailed classification of these regions, offering insights into the diverse geographical features across the United States.