Teton Range

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Teton Range
View from the east over the Snake River and Jackson Hole to the center of the Teton Range

View from the east over the Snake River and Jackson Hole to the center of the Teton Range

Highest peak Grand Teton ( 4200  m )
location Wyoming , Idaho (USA)
part of Rocky mountains
Coordinates 43 ° 45 ′  N , 110 ° 50 ′  W Coordinates: 43 ° 45 ′  N , 110 ° 50 ′  W
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Creation of the Teton Range
View from Jackson Lake Lodge over the Willow Flats wetland area to the peaks of the Teton Range.
North end of the Cathedral Group , the Grand Tetons in the center
Photo by Ansel Adams from 1942

The Teton Range is a mountain range in the Rocky Mountains . It extends about 100 km north-south in the US state of Wyoming on the Idaho border . The two most famous peaks of the chain are the Grand Teton with 4200 m and Mount Moran with 3837 m. The Grand Teton, Mount Owen (3940 m) and other striking peaks of the chain are located in a mountain range between the Cascade Canyon and Avalanche Canyon valleys , which is informally known as the Cathedral Group . Other sources narrow the Cathedral Group and only include the northern part between Cascade Canyon and Garnett Canyon with only six prominent peaks left. This mountain range also contains half of the remaining glaciers in the Teton Range, including the Teton Glacier, the largest glacier in the mountain range. Other well-known peaks south of the Cathedral Group are Mount Wister (3500 m) and Buck Mountain (3639 m).

The name Teton comes from early fur traders of French descent who named the Grand Teton because of its shape when viewed from the north after a female breast ( French téton ).

geology

The Teton Range is the most distinctive and geologically youngest chain of the Rocky Mountains. It forms the sharp transition between the prairies of the Great Plains and the Rocky Mountains. The bedrock of the Teton Range, as well as the adjacent part of the Rocky Mountains, consists of metamorphic gneiss , which was formed over long geological periods under pressure from sediments of an ancient sea. In cracks and crevices of the rock occasionally penetrated magma and froze in transitions to granite .

Plate tectonic processes unfolded the continuous mountain range of the Cordilleras , of which the Rocky Mountains are part , on both American continents around 80–40 million years ago . The breaking and shear forces that acted continued to have an effect for a long time and, together with the forces of erosion, led to a thinning of the earth's crust .

Before 13-9 million years originated in the emergence Basin and Range Province , the Teton- rejection in north-south direction. The crustal block was tipped up on the western side of the fracture; it forms today's Teton Range with its steep eastern and gentle western flanks. The eastern part of the crustal block, however, sagged and now forms the valley of Jackson Hole . This vertical shift amounts to around 10,000-11,000 meters in altitude, with the actually effective height difference being significantly reduced by the erosion that was simultaneously acting during the tilting. The erosion exposed the harder granite, the sharp edges of which characterize the striking peaks today, while the removed material partially filled in the valley below, creating the largely flat landscape of Jackson Hole. Today there are still 2100 m between the summit of Grand Teton and the valley floor. The low geological age of the mountain range explains the rugged shapes and steep trough valleys in the mountain range - the erosion did not have much time to grind away this rock and wash out the valleys.

The plain immediately below the mountains in Jackson Hole was washed out towards the end of the last Ice Age around 20,000 years ago, and the moraines that structure the plain today were deposited at the same time . The course of the Snake River and the lakes in Jackson Hole were formed about 15,000 years ago.

geography

The Teton Range extends north-south. It continues south from the Salt River Range . The small Big Hole Mountains adjoin to the southwest and determine the course of the Snake River, which follows the full length of the chain immediately below the eastern flank of the Teton Range, then bends to the west and northwest and thus roughly 3/4 of the mountain range. To the east lies Jackson Hole, to the west the valley of the Teton River .

There are no major rivers in the Teton Range. All rainfall drains to the Snake River; from the east side directly, from the west flank over the Teton River and the Henrys Fork in Idaho.

Almost the entire east flank of the Teton Range and the west of Jackson Hole are now part of the Grand Teton National Park , the west flank of the Targhee National Forest , a national forest . There are two wilderness areas in the Targhee National Forest : The Jedediah Smith Wilderness, named after the fur hunter and mountain man Jedediah Smith , and the one in the north, the small Winegar Hole Wilderness . Like all Wilderness Areas, both are nature reserves of the strictest class in the United States, without any human influence. To the southeast, the Bridger-Teton National Forest encompasses a small portion of the mountain range.

In the south of the Tetons is the Jackson Hole Ski Area , one of the largest and most famous ski areas in the United States. Another ski area called Grand Targhee Resort is located in the southwest.

Teton Range as namesake

The Teton Range gives its name to the genus Tetonius , which includes four extinct primate species from the Omomyidae family that were common in North America in the Eocene . The finds are between 55.8 and 48.6 million years old. Many North American primates in the Omomyidae family are named for different types of geographic barriers - primarily mountain ranges and rivers - that may be responsible for their diversity. An almost complete skull of the species Tetonius homunculus was discovered in the west of the Teton Range towards the end of the 19th century by the paleontologist Jacob L. Wortman of the Carnegie Museum of Natural History and scientifically described by Edward Drinker Cope .

Web links

Commons : Teton Range  - collection of images, videos and audio files

Individual evidence

  1. Grand Teton in the United States Geological Survey's Geographic Names Information System
  2. Mount Moran in the Geographic Names Information System of the United States Geological Survey
  3. ^ Fritiof Fryxell: The Tetons: Interpretations of a Mountain Landscape , 5th Edition, University of California Press, Berkeley and Los Angeles 1966, p. 11.
  4. ^ Peakbagger: Cathedral Group
  5. The description of the geology is based on JD Love: Teton mountain front, Wyoming . In: Geological Society of America, Centennial Field Guide - Rocky Mountain Section, Volume 2. Boulder, Colorado, Geological Society of America, 1987, ISBN 0-8137-5406-2 , pp. 173-178
  6. ^ Robert B. Smith, Lee J. Siegel: Windows into the Earth - The Geologic Story of Yellowstone and Grand Teton National Parks . Oxford University Press, 2000, ISBN 0-19-510596-6 , p. 102 f.
  7. C. Beard, M. Klingler, 2006. The Hunt for the Dawn Monkey: Unearthing the Origins of Monkeys, Apes, and Humans. Univ. of California Pr. ISBN 0520249860