Grand Teton National Park

Grand Teton National Park in northwestern Wyoming is famed for its history and natural beauty. It includes the Teton Range and the Middle Teton Glacier, which fills numerous glacial lakes; the Jackson Hole National Monument; and the Snake River. The park was established in 1929.

The 485 square mile (1,256 sq km) park is 45 miles (72 km) long from north to south, and at its widest is 26 miles (42 km). The 40-mile (64 km) long Teton Range includes the Grand Teton, with an elevation of 13,779 feet (4,198 m), and seven other peaks exceeding 12,000 feet (3,658 m). A mountain valley, Jackson Hole, is 55 miles (88 km) long and 13 miles (21 km) wide.

The park is home to numerous species of mammals, amphibians, invertebrates, birds, fish, and reptiles. It also houses hundreds of species of flowering plants and seven species of coniferous trees. Millions of visitors each year participate in a range of activities, including backpacking, boating, camping, hiking, horseback riding, mountain climbing, rafting, snowshoeing, and wildlife watching.

Background

The Teton mountains are relatively young, although the rocks from which they are formed are among the oldest in North America. The fault block mountain range comprises a large piece of the earth's crust along the Teton fault, which is located at the edge of the flats on Jackson Hole's western side. The Teton fault is a normal fault; the mountains are the result of uplift, while the valley is caused by down drop as the region stretches in an east-west direction. Numerous small seismic shifts periodically inch the range up slightly higher—on average, the fault rises 6 to 8 feet (1.8 to 2.4 m) on the mountainside, and falls 2 to 4 feet (0.6 to 1.2 m) on the valley side with each earthquake, for a total movement of 10 feet (3 m). Much of the fault line is buried under rock that has crumbled from the slopes and rock left behind by glaciers.

Because of its formation, the east face of the Teton Range is straight, with numerous fault scarps, which are cliffs and steep slopes. Glacial action has altered and worn away some of the mountain block. The range has no foothills and is asymmetrical.

Most of the Teton Range is composed of gneiss, a metamorphic rock, which is 2.7 billion years old. Gneiss forms when a mixture of volcanic debris and seafloor sediment is submerged by the collision of two tectonic plates and buried up to 18 miles (29 km) deep. The light and dark layers of the rock, indicating the presence of various minerals, resulted from intense heat and pressure. An igneous rock, granite, appears as crystalline stripes, and was formed by magma seeping between cracks in the gneiss and cooling 2.5 billion years ago. The tallest Teton peaks are mainly granite, which is harder than gneiss.

Around 775 million years ago, the region was stretched in a north to south direction. East-west cracks formed in the submerged gneiss and granite, and were filled by basaltic magma. It cooled to form diabase, an igneous rock, which can be seen in the faces of several peaks.

Sedimentary rock left from ancient seas lie over the igneous and metamorphic rocks in many places. These rocks, which contain fossils of trilobites, shells, and other ancient sea creatures, erode from the east.

Much of the landscape has been formed by glacial activity dating to the Pleistocene Ice Age. Many of the lakes are depressions formed by the glaciers, and many V-shaped canyons were widened to become U-shaped canyons. Glaciers also deposited cobbles and gravel. When they melted, they left behind moraines—long piles of rocky debris pushed by the edges of glaciers—where conifers grow. Many glacial lakes, including Jackson, Jenny, and Taggart, are ringed by moraines.

Overview

The earliest humans moved in as the glaciers receded at least eleven thousand years ago. For the most part, human inhabitants were present in the Tetons only seasonally. They gathered nuts and berries and hunted. As winter approached, game moved to areas with milder weather, and Native American tribes followed. Bannock, Blackfoot, Crow, Flathead, Gros Ventre, Nez Perce, and Shoshone were among the tribes that visited the area. The mountains were and remain sacred to the natives. Archaeologists have found many artifacts, including clay pottery, projectile points, bows and arrows, soapstone bowls, and a number of stone tools.

The first euro-American explorers were probably fur trappers who arrived during the early 1800s. By 1829, trapper Davey Jackson and his partners had set up a base in Jackson Hole to trap beavers. The beaver population was quickly depleted, however. By the 1860s, expeditions surveyed the region. The first homesteaders settled in Jackson Hole in 1884. They struggled against weather conditions, including long and harsh winters, and poor, sandy soil. By the early twentieth century, many ranchers relied on tourists from the East. The dude ranch, as such places were dubbed, became the industry of choice for decades.

An effort to preserve the region and prevent development during the 1920s led to the eventual establishment of the national park. John D. Rockefeller Jr. was taken by the scenery and began buying private land under the name Snake River Land Company. He eventually owned thirty-five thousand acres with the intention of donating the land to the federal government for parkland. Local residents were opposed to his plan, because federal land would not provide any local tax revenue. Following congressional hearings, the park—composed of the Teton Range and six glacial lakes—was formed in 1929. President Calvin Coolidge approved the act on February 26, 1929. The Rockefeller parcels were not included.

President Franklin D. Roosevelt declared the rest of the federal land in the valley the Jackson Hole National Monument in 1943. Six years later, Rockefeller was finally able to donate his land to the government. Congress encompassed the park, national monument, and donated Rockefeller land in 1950 as the Grand Teton National Park. Local ranchers continued to oppose the loss of the land in the valley, and after considerable disagreement, they succeeded in retaining grazing rights in the park.

National parks became increasingly popular after World War II (1939–1945). More people had cars, and many families took car trips across the country. Rockefeller built cabins and lodges near the Grand Teton National Park, and new visitor centers were constructed during the 1950s. In 2007, the Rockefeller family donated its retreat, JY Ranch, to the park. It is known as the Laurance S. Rockefeller Preserve.

Bibliography

"Grand Teton: Cultural History." National Park Service, www.nps.gov/grte/learn/historyculture/cultural.htm. Accessed 23 May 2017.

"Grand Teton: Geologic Activity." National Park Service, www.nps.gov/grte/learn/nature/geology.htm. Accessed 23 May 2017.

"Grand Teton: Learn about the Park." National Park Service, 26 Apr. 2022, www.nps.gov/grte/learn/index.htm. Accessed 23 May 2017.

"Grand Teton National Park." National Geographic, 9 May 2023, www.nationalgeographic.com/travel/national-parks/grand-teton-national-park/. Accessed 23 May 2017.

"Grand Teton: Snake River Land Company—Countdown: 22 Days." National Park Service, 3 Aug. 2012, www.nps.gov/grte/blogs/snake-river-land-company-countdown-22-days.htm. Accessed 23 May 2017.

"Mountain Uplift." National Park Service, www.nps.gov/parkhistory/online‗books/grte/grte‗geology/sec3.htm. Accessed 23 May 2017.

"Native American History." Jackson Hole Historical Society & Museum, jacksonholehistory.org/native-american-history/. Accessed 23 May 2017.