Black Canyon of the Gunnison National Park
Encyclopedia
Black Canyon of the Gunnison National Park is a United States National Park located in western Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...

, and managed by the National Park Service
National Park Service
The National Park Service is the U.S. federal agency that manages all national parks, many national monuments, and other conservation and historical properties with various title designations...

. There are two entrances to the park; the more-developed south rim entrance is located 15 miles (24 km) east of Montrose
Montrose, Colorado
The City of Montrose is a Home Rule Municipality that is the county seat and the most populous city of Montrose County, Colorado, United States. The United States Census Bureau estimates that the city population was 15,479 in 2005. The main road that leads in and out of Montrose is U.S...

, while the north rim entrance is located 11 miles (18 km) south of Crawford
Crawford, Colorado
The Town of Crawford is a Statutory Town in Delta County, Colorado, United States. The population was 366 at the 2000 census.-Geography:Crawford is located at ....

 and is closed in the winter. The park contains 12 miles (19.3 km) of the 48 miles (77.2 km) long canyon of the Gunnison river. The national park itself contains the deepest and most dramatic section of the canyon, but the canyon continues upstream into the Curecanti National Recreation Area
Curecanti National Recreation Area
Curecanti National Recreation Area, in Colorado, is formed by three reservoirs, named for corresponding dams on the Gunnison River. The national recreation area borders Black Canyon of the Gunnison National Park on the west...

 and downstream into the Gunnison Gorge National Conservation Area
Gunnison Gorge National Conservation Area
The Gunnison Gorge National Conservation Area is a National Conservation Area managed by the Bureau of Land Management . were designated in the Black Canyon of the Gunnison National Park and Gunnison Gorge National Conservation Area Act of 1999...

.

Geology

The Gunnison River
Gunnison River
The Gunnison River is a tributary of the Colorado River, long, in the Southwest state of Colorado. It is the fifth largest tributary of the Colorado River, with a mean flow of 4320 ft³/s .-Description:...

 drops an average of 34 feet per mile (5 m/km) through the entire canyon
Canyon
A canyon or gorge is a deep ravine between cliffs often carved from the landscape by a river. Rivers have a natural tendency to reach a baseline elevation, which is the same elevation as the body of water it will eventually drain into. This forms a canyon. Most canyons were formed by a process of...

, making the 5th steepest mountain descents in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

. In comparison, the Colorado River
Colorado River
The Colorado River , is a river in the Southwestern United States and northwestern Mexico, approximately long, draining a part of the arid regions on the western slope of the Rocky Mountains. The watershed of the Colorado River covers in parts of seven U.S. states and two Mexican states...

 through the Grand Canyon drops an average of 7.5 feet per mile (1.4 m/km). The greatest descent of the Gunnison River occurs in the park at Chasm View dropping 240 feet per mile (45 m/km). The Black Canyon is so named on account of its steepness which makes it difficult for sunlight to penetrate very far down the canyon. As a result, the canyon walls are most often in shadow, causing the rocky walls to appear black. At its narrowest point the canyon is only 40 feet (12 m) across at the river.

The extreme steepness and depth of the Black Canyon formed as the result of several geologic processes acting together. The Gunnison River is primarily responsible for carving the canyon, though several other geologic events had to occur in order to form the canyon as it is seen today.

Precambrian

The Precambrian
Precambrian
The Precambrian is the name which describes the large span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale...

 gneiss
Gneiss
Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks.-Etymology:...

 and schist
Schist
The schists constitute a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn-out grains to such an extent that a particular form called quartz schist is...

 that makes up the majority of the steep walls of the black canyon formed 1.7 billion years ago during a metamorphic period brought on by the collision of ancient volcanic island arcs with the southern end of what is present-day Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

. The lighter-colored pegmatite
Pegmatite
A pegmatite is a very crystalline, intrusive igneous rock composed of interlocking crystals usually larger than 2.5 cm in size; such rocks are referred to as pegmatitic....

 dikes
Dike (geology)
A dike or dyke in geology is a type of sheet intrusion referring to any geologic body that cuts discordantly across* planar wall rock structures, such as bedding or foliation...

 that can be seen crosscutting the basement rocks formed during this period as well.

Cretaceous - Tertiary

The entire area underwent uplift during the Laramide orogeny
Laramide orogeny
The Laramide orogeny was a period of mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago, and ended 35 to 55 million years ago. The exact duration and ages of beginning and end of the orogeny are in dispute, as is the cause. The Laramide...

 between 70 and 40 million years ago which was also part of the Gunnison Uplift. This raised the Precambrian gneisses and schists that make up the canyon walls. During the Tertiary
Tertiary
The Tertiary is a deprecated term for a geologic period 65 million to 2.6 million years ago. The Tertiary covered the time span between the superseded Secondary period and the Quaternary...

 from 26 to 35 million years ago large episodes of volcanism
Volcanism
Volcanism is the phenomenon connected with volcanoes and volcanic activity. It includes all phenomena resulting from and causing magma within the crust or mantle of a planet to rise through the crust and form volcanic rocks on the surface....

 occurred in the area immediately surrounding the present day Black Canyon. The West Elk Mountains
West Elk Mountains
The West Elk Mountains are a mountain range in the west-central part of the US state of Colorado. They lie primarily within the Gunnison National Forest, and part of the range is protected as the West Elk Wilderness...

, La Sal Mountains
La Sal Range
The La Sal Mountains are located in Grand and San Juan counties, near the eastern border of the state of Utah, and rising above the town of Moab. This range is part of the Manti-La Sal National Forest and the southern Rocky Mountains. The maximum elevation is at Mount Peale, reaching 12,721 feet ...

, Henry Mountains
Henry Mountains
The Henry Mountains are located in the southeastern portion of the U.S. state of Utah and run in a generally north-south direction, extending over a distance of about 30 miles . They were named by John Wesley Powell in honour of Joseph Henry, the first secretary of the Smithsonian Institution. The...

, and Abajo Mountains
Abajo Mountains
The Abajo Mountains, also called the Blue Mountains, is a small mountain range west of Monticello, Utah, south of Canyonlands National Park and north of Blanding, Utah. The mountain range is located within the Manti-La Sal National Forest...

 all contributed to burying the area in several thousand feet of volcanic ash
Volcanic ash
Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...

 and debris.

The modern Gunnison River set its course 15 million years ago as the run-off from the nearby La Sal and West Elk Mountains and the Sawatch Range
Sawatch Range
The Sawatch Range is a mountain range in central Colorado which includes eight of the twenty highest peaks in the Rocky Mountains, including Mount Elbert, at elevation, the highest peak in the Rockies....

 began carving through the relatively soft volcanic deposits.

Quaternary

With the Gunnison River’s course set, a broad uplift in the area from 2 to 3 million years ago caused the river to cut down through the softer volcanic deposits. Eventually the river reached the Precambrian rocks of the Gunnison Uplift. Since the river was unable to change its course, it began scouring through the extremely hard metamorphic rocks of the Gunnison Uplift. The river’s flow was much larger than currently, with much higher levels of turbidity
Turbidity
Turbidity is the cloudiness or haziness of a fluid caused by individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality....

. As a result the river dug down through the Precambrian gneiss and schist at the rate of 1 inches (25.4 mm) every 100 years. The extreme hardness of the metamorphic rock along with the relative quickness with which the river carved through them created the steep walls that can be seen today.

A number of feeder canyons running into the Black Canyon slope in the wrong direction for water to flow into the canyon. It is believed that less-entrenched streams in the region have shifted to a more north-flowing drainage pattern
Drainage system (Geomorphology)
In geomorphology, a drainage system is the pattern formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of the land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. Geomorphologists and...

 in response to a change in the tilt of the surrounding terrain. The west-flowing Gunnison, however, was essentially trapped in the hard Precambrian rock of the Black Canyon and could not change its course.

History

The Ute
Ute Tribe
The Ute are an American Indian people now living primarily in Utah and Colorado. There are three Ute tribal reservations: Uintah-Ouray in northeastern Utah ; Southern Ute in Colorado ; and Ute Mountain which primarily lies in Colorado, but extends to Utah and New Mexico . The name of the state of...

 Indians had known the canyon to exist for a long time before the first Europeans saw it. By the time the United States gained independence
United States Declaration of Independence
The Declaration of Independence was a statement adopted by the Continental Congress on July 4, 1776, which announced that the thirteen American colonies then at war with Great Britain regarded themselves as independent states, and no longer a part of the British Empire. John Adams put forth a...

 in 1776, two Spanish
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

 expeditions had passed by the canyons. In the 1800s, the numerous fur trappers searching for beaver pelts would have known of the canyon's existence but they left no written record.

In 1881, the Denver and Rio Grande had reached Gunnison from Denver. It pushed its narrow gauge
Narrow gauge
A narrow gauge railway is a railway that has a track gauge narrower than the of standard gauge railways. Most existing narrow gauge railways have gauges of between and .- Overview :...

 line through the canyon in 1882, taking a year to build the last mile. In March, 1883, it completed its connection to Salt Lake City and for a brief period the canyon was on the main line of a transcontinental railroad system. By 1890, the alternate route through Glenwood Springs
Glenwood Springs, Colorado
The City of Glenwood Springs is a Home Rule Municipality that is the county seat and the most populous city of Garfield County, Colorado, United States. The United States Census Bureau estimated that the city population was 8,564 in 2005...

 had been completed and the route through the Black Canyon, being more difficult to operate, lost importance for through trains. The route was finally abandoned in 1955.

While the railroad and others came first to the canyon as a path to Utah and the mines to the southwest, later visitors came to see the canyon as an opportunity for recreation and personal enjoyment.
The area was established as a U.S. National Monument
U.S. National Monument
A National Monument in the United States is a protected area that is similar to a National Park except that the President of the United States can quickly declare an area of the United States to be a National Monument without the approval of Congress. National monuments receive less funding and...

 on March 2, 1933 and made into a National Park
National park
A national park is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns. Although individual nations designate their own national parks differently A national park is a reserve of natural, semi-natural, or developed land that a sovereign state declares or...

 on October 21, 1999.

Biology

The Black Canyon of the Gunnison National Park contains a wide variety of flora and fauna. Some common plants that are native to the park include Aspen
Aspen
Populus section Populus, of the Populus genus, includes the aspen trees and the white poplar Populus alba. The five typical aspens are all native to cold regions with cool summers, in the north of the Northern Hemisphere, extending south at high altitudes in the mountains. The White Poplar, by...

, Ponderosa pine
Ponderosa Pine
Pinus ponderosa, commonly known as the Ponderosa Pine, Bull Pine, Blackjack Pine, or Western Yellow Pine, is a widespread and variable pine native to western North America. It was first described by David Douglas in 1826, from eastern Washington near present-day Spokane...

, Sagebrush
Sagebrush
Sagebrush is a common name of a number of shrubby plant species in the genus Artemisia native to western North America;Or, the sagebrush steppe ecoregion, having one or more kinds of sagebrush, bunchgrasses and others;...

,
Desert Mahogany
Mahogany
The name mahogany is used when referring to numerous varieties of dark-colored hardwood. It is a native American word originally used for the wood of the species Swietenia mahagoni, known as West Indian or Cuban mahogany....

, Utah Juniper, Gambel oak
Gambel oak
Quercus gambelii, or Gambel oak, is a deciduous small tree or large shrub widespread in the foothills and lower mountain elevations of the central southwestern United States and northwestern Mexico: its range is centered on the Colorado Plateau–Four Corners states of Utah-Colorado,...

 (scrub oak) and Singleleaf Ash
Ash tree
Fraxinus is a genus flowering plants in the olive and lilac family, Oleaceae. It contains 45-65 species of usually medium to large trees, mostly deciduous though a few subtropical species are evergreen. The tree's common English name, ash, goes back to the Old English æsc, while the generic name...

.
Wildlife in the park include coyotes, elk
Elk
The Elk is the large deer, also called Cervus canadensis or wapiti, of North America and eastern Asia.Elk may also refer to:Other antlered mammals:...

, magpies, eagle
Eagle
Eagles are members of the bird family Accipitridae, and belong to several genera which are not necessarily closely related to each other. Most of the more than 60 species occur in Eurasia and Africa. Outside this area, just two species can be found in the United States and Canada, nine more in...

s, and the mule deer
Mule Deer
The mule deer is a deer indigenous to western North America. The Mule Deer gets its name from its large mule-like ears. There are believed to be several subspecies, including the black-tailed deer...

. In addition the canyon is the home of a number of resident birds including the Great Horned Owl
Great Horned Owl
The Great Horned Owl, , also known as the Tiger Owl, is a large owl native to the Americas. It is an adaptable bird with a vast range and is the most widely distributed true owl in the Americas.-Description:...

, the American dipper
American Dipper
The American Dipper , also known as a Water Ouzel, is a stocky dark grey bird with a head sometimes tinged with brown, and white feathers on the eyelids cause the eyes to flash white as the bird blinks. It is 16.5 cm long and weighs on average 46 g...

 and Steller's Jay
Steller's Jay
The Steller's Jay is a jay native to western North America, closely related to the Blue Jay found in the rest of the continent, but with a black head and upper body. It is also known as the Long-crested Jay, Mountain Jay, and Pine Jay...

 and migratory birds such as the Mountain Bluebird
Mountain Bluebird
The Mountain Bluebird is a medium-sized bird weighing about 2-5 ounces, with a length from 15–20 cm . They have light underbellies and black eyes. Adult males have thin bills are bright turquoise-blue and somewhat lighter beneath. Adult females have duller blue wings and tail, grey breast,...

, the Peregrine Falcon
Peregrine Falcon
The Peregrine Falcon , also known as the Peregrine, and historically as the Duck Hawk in North America, is a widespread bird of prey in the family Falconidae. A large, crow-sized falcon, it has a blue-gray back, barred white underparts, and a black head and "moustache"...

, the White-throated Swift
White-throated Swift
The White-throated Swift is a swift of the family Apodidae native to western North America, south to cordilleran western Honduras...

 and the Canyon Wren
Canyon Wren
The Canyon Wren is a small North American wren, and is about 14.5 cm long. It ranges from far southern British Columbia and Montana south through much of Mexico to western Chiapas and east to Oklahoma and Texas...

.

Attractions

The main attraction of the park is the scenic drive along the south rim. At the south rim there are two campgrounds and several miles (kilometers) of hiking
Hiking
Hiking is an outdoor activity which consists of walking in natural environments, often in mountainous or other scenic terrain. People often hike on hiking trails. It is such a popular activity that there are numerous hiking organizations worldwide. The health benefits of different types of hiking...

 and nature trails. The north rim is accessible by automobile, though it is quite remote, and has a small, primitive campground. The river can be accessed by automobile or by foot. Automobiles can access the river via the East Portal Road at the south rim, this road has a 16% grade, and is prohibited to vehicles over 22 feet (7 m) in length. The river can also be accessed by steep, unmaintained trails called routes or draws on the north and south rim. These take between two hours to hike down and two to four hours to hike back up depending on the which route is taken. A free back country permit is required for all inner canyon use. Most routes have campsites at the river.

The Black Canyon is a center for rock climbing
Rock climbing
Rock climbing also lightly called 'The Gravity Game', is a sport in which participants climb up, down or across natural rock formations or artificial rock walls. The goal is to reach the summit of a formation or the endpoint of a pre-defined route without falling...

, in a style known as traditional climbing
Traditional climbing
Traditional climbing, or trad climbing, is a style of rock climbing in which a climber or group of climbers places all gear required to protect against falls , and removes it when a passage is complete...

. Most of the climbs are difficult and are only done by advanced climbers.

Rafting opportunities exist in the region, but the run through the park itself is a difficult technical run for only the best kayakers. There are several impassible stretches of water requiring long, sometimes dangerous portages to get around. The remaining rapids are class III - V, and are for expert river runners only. Downstream, in the Gunnison Gorge National Conservation Area, the river is somewhat easier, though still very remote and for experienced runners only, with rapids that are Class III - IV.

External links

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