Piedmont Physiography Topics

1. Regional Setting
2. Extent and Boundaries
3. Characteristic Features
4. Piedmont Drainage
• Introduction to Physiography
• Coastal Plain
• Piedmont
• Mesozoic Basins
• Blue Ridge
• Valley and Ridge
• Appalachian Plateaus
• Virginia's Rivers


Piedmont Physiography: Characteristic Features

• The Piedmont has gently rolling hills with low ridges and shallow stream valleys.

Above: Typical view of the Piedmont surface from Fancy Gap Mountain. The Piedmont has a rolling landscape meaning that it is a surface of gentle slopes where valleys and hills merge without any well-defined break in slope. (Photograph by Robert Whisonant)

Piedmont physiography between Charlottesville and Richmond in Central Virginia. Many geologists believe that the low-relief Piedmont surface is very old and must represent many millions of years of erosion. (Base map from The National Map, U.S. Geological Survey)

• Monadnocks are present in the Piedmont.  Monadnocks are isolated hills that rise sharply from the low, nearly featureless Piedmont surface around them.

Willis Mountain in Buckingham County, as shown on the topographic map and in the image above, is an excellent example of a monadnock.  Monadnocks stand high above the Piedmont surface because they are made of rocks that are more resistant to erosion than the surrounding rocks.

• Saprolite is present in much of the Piedmont as well.  The word saprolite literally means rotten rock and refers to the soft, reddish, decomposed rock material that covers much of the Piedmont.

Saprolite, shown here in a road cut near Charlottesville, is a soft, clay-rich decayed rock material formed by the deep chemical weathering of igneous and metamorphic rocks. In some places in the Piedmont the saprolite is over a hundred feet thick. Because of the saprolite, few fresh rocks are exposed in this province. (Photograph by Stan Johnson)