Marker Logo HMdb.org THE HISTORICAL
MARKER DATABASE
“Bite-Size Bits of Local, National, and Global History”
“Bite-Size Bits of Local, National, and Global History”
Near Hulett in Crook County, Wyoming — The American West (Mountains)
 

How Did the Tower Form?

Devils Tower National Monument

 
 
How Did the Tower Form? Marker image. Click for full size.
By Duane Hall, July 27, 2010
1. How Did the Tower Form? Marker
Inscription. The process began about 50 million years ago. Magma (molten rock) was injected into layers of sedimentary rock, forming the Tower one and one-half miles below the earth’s surface. It has since taken millions of years to erode away the surrounding sedimentary rock to expose the Tower we see today.

Geologists agree the Tower is an igneous (hardened magma) intrusion, but have three different interpretations of the Tower’s original size and shape. Because of erosion, we may never know which interpretation is correct.

Three Possible Interpretations

Igneous Stock:
The Tower is an irregularly shaped, igneous intrusion called a stock. It was formed when magma cooled and crystallized before reaching the earth’s surface.

Laccolith:
The Tower is the remnant of a mushroom-shaped, igneous intrusion. As with the igneous stock, the magma solidified before reaching the earth’s surface.

Volcanic Plug:
The Tower is a cylinder-shaped igneous intrusion, part of the plumbing system that fed a volcano. The pipe feeding the volcano became plugged when the magma solidified underground.
 
Erected by National Park Service.
 
Location. 44° 35.393′ N, 104° 43.071′ 
Devils Tower image. Click for full size.
By Duane Hall, July 27, 2010
2. Devils Tower
View to north from State Route 24
W. Marker is near Hulett, Wyoming, in Crook County. Marker can be reached from State Highway 110. Touch for map. Marker is located in Devils Tower National Monument; drive to the end of State Route 110 to the parking lot of the Devils Tower Visitor Center. Marker is in this post office area: Hulett WY 82720, United States of America.
 
Other nearby markers. At least 7 other markers are within 3 miles of this marker, measured as the crow flies. Buried Tower (within shouting distance of this marker); People of the Land (about 400 feet away, measured in a direct line); Devils Tower ... the first National Monument (about 500 feet away); Friends, Family, and Fun (about 500 feet away); Life Above and Below Ground (approx. 0.6 miles away); Devils Tower (approx. 2.6 miles away); a different marker also named Devils Tower (approx. 2.6 miles away).
 
More about this marker. Marker is along the southwest segment of the Tower Trail which circles Devils Tower. It is a 1/4 mile walk from the Visitor Center parking lot to the marker.
 
Also see . . .  Devils Tower National Monument. Official National Park Service website. (Submitted on March 25, 2014.) 
 
Categories. Notable Places
 
Devils Tower image. Click for full size.
By Duane Hall, July 27, 2010
3. Devils Tower
View to northeast from Tower Trail
Southwest Face of Devils Tower image. Click for full size.
By Duane Hall, July 27, 2010
4. Southwest Face of Devils Tower
View from Tower Trail
 
 
Credits. This page was last revised on June 16, 2016. This page originally submitted on March 25, 2014, by Duane Hall of Abilene, Texas. This page has been viewed 279 times since then and 27 times this year. Photos:   1, 2, 3, 4. submitted on March 25, 2014, by Duane Hall of Abilene, Texas.
 
Editor’s want-list for this marker. Photo of wide-view of marker and surroundings. • Can you help?
Paid Advertisement