Home Archived Aug 4, 2016

USGS Geology in the Parks

Geologic Provinces of the United States: Interior Plains gallery

Great Falls of the Potomac River

The Green River Valley

Mammoth Caves National Park
Photo by Phil Stoffer, USGS

The Green River has incised into the Pennyroal Plateau, a part of the ancient landscape surface that extended across the entire midwest region prior to the periods of glaciation starting in the Pliocene Epoch (about 5 million years ago).


Entrance to Delaware Water Gap

Trail to Historic Cave Entrance

Mammoth Cave National Park
Photo by Phil Stoffer, USGS

The caprock of the Pennyroyal Plateau in the Mammoth Cave region are sandstone, shale, and conglomeratic beds.


Delaware River

First Creek Trail

Mammoth Cave National Park
Photo by Phil Stoffer, USGS

The Delaware River makes a sweeping bend as it heads throogh the world-famous Delaware Water Gap. The bend of the river mimics the underlying geology.


| Pacific | | Columbia Plateau | | Basin and Range | | Colorado Plateau | | Rocky Mountain | | Laurentian Upland| | Interior Plains | | Interior Highlands | | Appalachian Highlands | | Atlantic Plain | | Alaskan | | Hawaiian | | Geologic province home | | Geologic time | | Plate tectonics | | Tapestry of Time and Terrain |

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://geomaps.wr.usgs.gov/parks/province/intgal.html
Page Contact Information: Webmaster
Page Last Modified: 02-Oct-2014@17:10