Geology and Ecology of National Parks

Devils Tower National Monument Standard Photo Tour

 

Devils Tower National Monument

Park entrance of Devils Tower National Monument on a cold March morning, 2009. Devils Tower is located in northeastern Wyoming near the town of Sundance. The park is physiographically located along northwestern boundary of the Black Hills. Devils Tower is "widely known as an outstanding example of columnar jointing and also as a remarkable physiographic feature" (Dutton and Schwartz, 1936).

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

Devils Tower in Devils Tower National Monument is a steep sided igneous body that displays spectacular columnar jointing. The igneous rocks of Devils Tower formed about 40 million years ago (Halvorson, 1980)when molten magma intruded the sedimentary rocks of the Black Hills region. Geologists debate whether or not the magma reached the surface as a volcanic eruption. As the magma cooled and hardened, it cracked, forming spectacular columns. Overlying rocks and surrounding sedimentary rocks have been eroded away, allowing Monument visitors a view of these striking joint patterns.

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

The striated surface of Devils Tower reflects the polygonal shaped fractures (columnar joints) that formed as magma contracted as it cooled and hardened.

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

This view shows the large rubble blocks that make up the talus apron around the base of Devils Tower. The tower consists of mostly a dark igneous rock called phonolite, being coarsely porphyritic (bearing crystals including both mafic and feldspar minerals) in a fine (aphanitic) olive-gray groundmass. Much of it has a welded breccia texture (Karner and Halvorson, 1987).

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

View of the rugged talus slope at the base of Devils Tower.

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

View of the rugged talus slope at the base of Devils Tower.

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

View of Devils Tower from its western flank. The stone tower rises 1,267 feet (386 m) above the nearby Belle Fourche River. The nearly flat top has an elevation of 5,070 feet (1,545 m).

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

This view of Devils Tower is along the park access road on the west side of the tower. The photo was taken in early morning light with the sun behind the butte.

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

This view is looking at Devils Tower's southeastern flank. Devils Tower is located roughly along the boundary between the pine woodlands of the uplands of the Black Hills Province (within the greater Rocky Mountains Physiographic Province) and the windswept prairie grasslands of the western Great Plains of northeastern Wyoming (Vigil and others, 2002).

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

Zoomed-in view of the south side of the Devils Tower in early morning light.

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

Snow blankets outcrops of red sediments of Permian to Jurassic strata exposed in bluffs along the Belle Fourche River in Devils Tower National Monument. These sedimentary formations dip gently to the west away from the Black Hills uplift (DeWitt and others, 1989; NPS, 2008).

(Credit: Phil Stoffer, USGS. Public domain.)

Devils Tower National Monument

This view is looking northwest at Devils Tower from along Wyoming Highway 24 near Moorcroft, Wyoming.

(Credit: Phil Stoffer, USGS. Public domain.)