Devils Tower National Monument
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| Devils Tower National Monument | |
|---|---|
| IUCN Category III (Natural Monument) | |
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| Location | Crook County, Wyoming, USA |
| Nearest city | Hulett, Wyoming |
| Coordinates | |
| Area | 1,346.91 acres (545.1 ha) |
| Established | September 24, 1906 |
| Visitors | 386,558 (in 2004) |
| Governing body | National Park Service |
Devils Tower (Lakota: Mato Tipila, which means “Bear Tower”) is a monolithic igneous intrusion or volcanic neck located in the Black Hills near Hulett and Sundance in Crook County, northeastern Wyoming, above the Belle Fourche River. It rises dramatically 1,267 feet (386 m) above the surrounding terrain and the summit is 5,112 feet (1,558 m) above sea level.
Devils Tower was the first declared United States National Monument, established on September 24, 1906 by President Theodore Roosevelt. The Monument's boundary encloses an area of 1,347 acres (5.45 km²).
In recent years about 1% of the Monument's 400,000 annual visitors climb Devils Tower, mostly through traditional climbing ("trad") techniques. The monolith is featured prominently in the 1977 film Close Encounters of the Third Kind.
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[edit] Name
Tribes including the Arapaho, Crow, Cheyenne, Kiowa, Lakota, and Shoshone had cultural and geographical ties to the monolith before European and early American immigrants reached Wyoming. Their names for the monolith include: Aloft on a Rock (Kiowa), Bear's House (Cheyenne, Crow), Bear's Lair (Cheyenne, Crow), Bear's Lodge (Cheyenne, Lakota), Bear's Lodge Butte (Lakota), Bear's Tipi (Arapaho, Cheyenne), Tree Rock (Kiowa), and Grizzly Bear Lodge (Lakota).
The name Devils Tower probably originated in 1875 during an expedition led by Col. Richard Irving Dodge when his interpreter misinterpreted the name to mean Bad God's Tower. This was later shortened to Devils Tower. [1] All information signs and references use the name "Devils Tower", following geographic naming standards wherein the apostrophe is eliminated.[1]
In 2005, a proposal to recognize these ties through the additional designation of the monolith as Bear Lodge National Historic Landmark met with opposition from Rep. Barbara Cubin, arguing that a "name change will harm the tourist trade and bring economic hardship to area communities" [2].
[edit] Geological history
Most of the landscape surrounding Devils Tower is composed of sedimentary rocks.
The oldest rocks visible in Devils Tower National Monument were laid down in a shallow sea during the Triassic period, 225 to 195 million years ago. This dark red sandstone and maroon siltstone, interbedded with shale, can be seen along the Belle Fourche River. Oxidation of iron minerals causes the redness of the rocks. This rock layer is known as the Spearfish formation.
Above the Spearfish formation is a thin band of white gypsum, called the Gypsum Spring Formation. This layer of gypsum was deposited during the Jurassic period, 195 to 136 million years ago.
Created as sea levels and climates repeatedly changed, gray-green shales (deposited in low-oxygen environments such as marshes) were interbedded with fine-grained sandstones, limestones, and sometimes thin beds of red mudstone. This composition, called the Stockade Beaver member, is part of the Sundance formation. The Hulett Sandstone member, also part of the Sundance formation, is composed of yellow fine-grained sandstone. Resistant to weathering, it forms the nearly vertical cliffs which encircle the Tower itself.
About 65 million years ago, during the Tertiary period, the Rocky Mountains and the Black Hills were uplifted. Molten magma rose through the crust, intruding into the already existing sedimentary rock layers.
[edit] Theories of formation
Geologists agree that Devils Tower was formed by the intrusion of igneous material. What they cannot agree upon is how, exactly, that process took place. Geologists Carpenter and Russell studied Devils Tower in the late 1800s and came to the conclusion that the Tower was indeed formed by an igneous intrusion. Later geologists searched for further explanations. Several geologists believe the molten rock comprising the Tower might not have surfaced; other researchers are convinced the tower is all that remains of what once was a large explosive volcano.
In 1907, scientists Darton and O'Hara decided that Devils Tower must be an eroded remnant of a laccolith. A laccolith is a large mass of igneous rock which is intruded through sedimentary rock beds but does not actually reach the surface, producing a rounded bulge in the sedimentary layers above. This theory was quite popular in the early 1900s since numerous studies had earlier been done on a number of laccoliths in the Southwest.
Other theories have suggested that Devils Tower is a volcanic plug or that it is the neck of an extinct volcano. Presumably, if Devils Tower was a volcanic plug, any volcanics created by it — volcanic ash, lava flows, volcanic debris — would have been eroded away long ago. Some pyroclastic material of the same age as Devils Tower has been identified elsewhere in Wyoming.
Geologists agree that the igneous material intruded and then cooled as phonolite porphyry, a light to dark-gray or greenish-gray igneous trachyte rock with conspicuous crystals of white feldspar. As the lava cooled, hexagonal (and sometimes 4-, 5-, and 7-sided) columns formed. As the rock continued to cool, the vertical columns shrank horizontally in volume and cracks began to occur at 120 degree angles, generally forming compact 6-sided columns. Superficially similar, but with typically 2 feet (0.61 m) diameter columns, Devils Postpile National Monument and Giant's Causeway are columnar basalt.
Until erosion began its relentless work, Devils Tower was not visible above the overlying sedimentary rocks. But the forces of erosion, particularly that of water, began to wear away the sandstones and shales. The much harder igneous rock survived the onslaught of erosional forces, and the gray columns of Devils Tower began to appear above the surrounding landscape.
As rain and snow continue to erode the sedimentary rocks surrounding the Tower's base, and the Belle Fourche River carries away the debris, more of Devils Tower will be exposed. But at the same time, the Tower itself is slowly being eroded: cracks that form the columns are subject to water and ice, becoming larger. Rocks are continually breaking off and falling from the steep walls, and occasionally entire columns fall. Piles of scree — broken columns, boulders, small rocks, and stones — lie at the base of the tower, indicating that it once was larger than it is today.
[edit] Recent history
Fur trappers may have visited Devils Tower, but they left no written evidence of having done so. The first documented visitors were several members of Captain W. F. Raynold's Yellowstone Expedition who arrived in 1859. Sixteen years later, Colonel Richard I. Dodge led a U.S. Geological Survey party to the massive rock formation and coined the name Devils Tower. Recognizing its unique characteristics, Congress designated the area a U.S. forest reserve in 1892 and in 1906 Devils Tower became the nation's first national monument.
The 1977 movie Close Encounters of the Third Kind used Devils Tower as a central plot element and as a location for its climactic scenes.
[edit] Climbing
In recent years, climbing Devils Tower National Monument has increased in popularity. Yet men have been climbing the tower for centuries. The first known ascent of Devils Tower by any method occurred on July 4, 1893, and is accredited to William Rogers, a local rancher in the area. William Rogers completed this first ascent after constructing a ladder of wooden pegs driven into cracks in the rock face. A few of these wooden pegs are still intact and are visible on the tower when hiking along the 1.3 mile Tower Trail at Devils Tower National Monument. While William Rogers may technically have been the first man to reach the summit, the man most famous for first climbing the tower using technical rock climbing techniques is Fritz Wiessner, who first reached the summit in 1937 with a small party from the American Alpine Club.
Today hundreds of climbers scale the sheer rock walls of Devils Tower each summer. These climbers ascend the tower on every side, climbing up the various vertical cracks and columns of the rock face. These paths, called climbing routes, are defined by the lava flow which formed Devils Tower. Moreover, the difficulty of these routes vary greatly, ranging from relatively easy to some of the hardest in the world. On some routes the gap between columns is just narrow enough to bridge with stretched-out legs, so the climber ascends doing "the splits" all the way. All climbers must register with a park ranger before and after attempting a climb.
[edit] Native American folklore
American Indian legends tell of six Sioux girls who were picking flowers when they were chased by bears. Feeling sorry for them, the Great Spirit raised the ground beneath the girls. The bears tried to climb the rock, but fell off, leaving their scratch marks on the sides.
Another version tells of how two Sioux boys wandered far from their village when Mato the bear, a huge creature that had claws the size of teepee poles, spotted them, and wanted to eat them for breakfast. He was almost upon them when the boys prayed to Wakan Tanka the Creator to help them. They rose up on a huge rock, while Mato tried to get up from every side, leaving huge scratch marks as he did. Finally, he sauntered off, disappointed and discouraged. The bear came to rest east of the Black Hills at what is now Bear Butte. Wanblee, the eagle, helped the boys off the rock and back to their village. A painting depicting this legend by artist Herbert A. Collins hangs over the fireplace in the visitor's center at Devil's Tower.
The Tower is sacred to several Native American Plains tribes, including the Lakota Sioux, Cheyenne and Kiowa. Because of this, many Indian leaders objected to climbers ascending the monument, as they felt this was a desecration. The climbers felt that they had a right to climb the Tower, since it is on federal land. A compromise was eventually reached with a voluntary climbing ban during the month of June when the tribes are conducting ceremonies around the monument. Climbers are asked, but not required, to stay off the Tower in June. According to the PBS documentary In Light of Reverence, approximately 85% of climbers honor the ban and voluntarily choose not to climb the Tower during the month of June. However, several climbers along with the Mountain States Legal Foundation sued the Park Service, claiming an inappropriate government entanglement with religion.[3]
[edit] References
- ^ USGS Frequently Asked Questions. United States Geographical Service. Retrieved on 2008-05-01.
[edit] External links
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