Black Canyon of the Gunnison National Park

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Black Canyon of the Gunnison
IUCN category II (national park)
BlackCanyon.JPG
Gunnison River at the base of Black Canyon of the Gunnison
Map showing the location of Black Canyon of the Gunnison
Map showing the location of Black Canyon of the Gunnison
Location Montrose County, Colorado, USA
Nearest city Montrose
Coordinates 38°34′0″N 107°43′0″W / 38.56667°N 107.71667°W / 38.56667; -107.71667Coordinates: 38°34′0″N 107°43′0″W / 38.56667°N 107.71667°W / 38.56667; -107.71667
Area 30,750 acres (12,440 ha)[1]
Established October 21, 1999
Visitors 168,336 (in 2011)[2]
Governing body National Park Service

Black Canyon of the Gunnison National Park is a United States National Park located in western Colorado and managed by the National Park Service. There are three entrances to the park. The more-developed east entrance is located 37 miles (59 km) east of Montrose and just west of Blue Mesa Reservoir by Blue Mesa Point. The south rim entrance is located 15 miles (24 km) east of Montrose, while the north rim entrance is 11 miles (18 km) south of Crawford and is closed in the winter. The park contains 12 miles (19 km) of the 48-mile (77 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 Curecanti National Recreation Area and downstream into Gunnison Gorge National Conservation Area.

Geology[edit]

Black Canyon of the Gunnison

The Gunnison River drops an average of 34 feet per mile (5 m/km) through the entire canyon, making it the 5th steepest mountain descent in North America. By comparison, the Colorado River drops an average of 7.5 feet per mile (1.4 m/km) through the Grand Canyon. The greatest descent of the Gunnison River occurs within the park at Chasm View dropping 240 feet per mile (45 m/km).[3] The Black Canyon is so named due its steepness which makes it difficult for sunlight to penetrate into its depths. As a result, the canyon is often shrouded in shadow, causing the rocky walls to appear black. At its narrowest point the canyon is only 40 feet (12 m) wide at the river.[3][4]

The extremely narrow walls of the canyon
Overview Black Canyon with Gunnison 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.[5]

Painted Wall on the north side of the canyon. It is the tallest sheer cliff in Colorado at 2,250 feet (690 m). Lighter-colored pegmatite dikes are clearly visible.

Precambrian[edit]

The Precambrian gneiss and schist that make 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. The lighter-colored pegmatite dikes that can be seen crosscutting the basement rocks formed later during this same period.[6]

Cretaceous - Tertiary[edit]

The entire area underwent uplift during the Laramide orogeny between 70 and 40 million years ago which was also part of the Gunnison Uplift. This raised the Precambrian gneiss and schist that makes up the canyon walls. During the Tertiary from 26 to 35 million years ago large episodes of volcanism occurred in the area immediately surrounding the present day Black Canyon. The West Elk Mountains, La Sal Mountains, Henry Mountains, and Abajo Mountains all contributed to burying the area in several thousand feet of volcanic ash and debris.[7]

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 began carving through the relatively soft volcanic deposits.[7]

Quaternary[edit]

With the Gunnison River’s course set, a broad uplift in the area 2 to 3 million years ago caused the river to cut 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. As a result the river dug down through the Precambrian gneiss and schist at the rate of 1-inch (25 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.[7]

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 shifted to a more north-flowing drainage pattern 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.[8]

History[edit]

The Ute 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 in 1776, two Spanish 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 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, an alternate route through Glenwood Springs 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.[9]

While the railroad and early visitors used the canyon as a path to Utah and mines to the southwest, later visitors came to see the canyon as an opportunity for recreation and personal enjoyment.[10] The area was established as a U.S. National Monument on March 2, 1933. It became a National Park on October 21, 1999.[11] During 1933-35, the Civilian Conservation Corps built the North Rim Road to design by the National Park Service. This includes fives miles of roadway and five overlooks; it is listed on the U.S.National Register of Historic Places as a historic district.[12]

Biology[edit]

Great Horned Owl chicks nesting in the Rocky Mountains
Juniper tree near the top of the canyon

The Black Canyon of the Gunnison National Park contains a wide variety of flora and fauna. Some common plants native to the park include aspen, Ponderosa pine, sagebrush, desert mahogany (Cercocarpus ledifolius), Utah juniper, gambel oak (scrub oak) and single-leaf ash.[13] The Black Canyon gilia (Aliciella penstemonoides) is a species of wildflower native to the park.[14] Wildlife in the park include the coyote, elk, magpie, eagle, and mule deer. In addition, the canyon is the home of a number of resident birds including the Great Horned Owl, American dipper and Steller's Jay as well as migratory birds such as the Mountain Bluebird, Peregrine Falcon, White-throated Swift and Canyon Wren.[15]

Attractions[edit]

The main attraction of the park is the scenic drive along US Highway 50 and Colorado Highway 92, as well as the south rim. The west end of the park, where it meet Blue Mesa Reservoir at Blue Mesa Point, is the area most developed for camping. It includes tent camping and RV parking with full hookups as well as canyon tours, hiking, fishing and boat tours. The west end of the park has river access by automobile, as well as guided tours of the canyon. A short hike at Blue Mesa Point Information Center heads down to Pine Creek and the Morrow Point boat tours, boating, fishing and hiking. At the south rim there are two campgrounds and several hiking and nature trails. The north rim is quite beautiful. It is also accessible by automobile and has a small, primitive campground. 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 routes require about 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 except at the west end.

The Black Canyon is a center for rock climbing in a style known as traditional climbing. Most of the climbs are difficult and attempted only by advanced climbers.[16]

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 impassable stretches of water requiring long, sometimes dangerous portages. The remaining rapids are class III - V, and are only for expert river runners.[17] Downstream, in the Gunnison Gorge National Conservation Area, the river is somewhat easier to navigate, though still very remote and only for experienced runners, with rapids that are Class III - IV.[18][19]

References[edit]

  1. ^ "Listing of acreage as of December 31, 2011". Land Resource Division, National Park Service. Retrieved 2012-03-06. 
  2. ^ "NPS Annual Recreation Visits Report". National Park Service. Retrieved 2012-03-06. 
  3. ^ a b "Black Canyon Dimensions". National Park Service. Retrieved 2007-07-29. 
  4. ^ "Black Canyon of the Gunnison National Park- Things To Know Before You Go". National Park Service. 2006-09-05. Retrieved 2006-10-27. 
  5. ^ "Black Canyon of the Gunnison National Park- The Geologic Story". National Park Service. 2006-07-25. Retrieved 2006-10-27. 
  6. ^ Tweto, O (1980). Colorado Geology. Rocky Mountain Association of Geologists. pp. 37–46. 
  7. ^ a b c Trista Thornberry-Ehrlich (2005). Black Canyon of the Gunnison National Park & Curecanti National Recreation Area: Geologic Resource Evaluation Report (PDF). Retrieved 2006-10-27. 
  8. ^ "Black Canyon of the Gunnison National Park : From Past to Present". National Park Service. Retrieved 2007-07-29. 
  9. ^ Athearn, Robert (1977). The Denver and Rio Grande Western Railroad. University of Nebraska Press. ISBN 0-8032-0920-7. 
  10. ^ "BCOTGNP : History & Culture : Animals". National Park Service. Retrieved 2007-07-29. 
  11. ^ "Cornell University Law School - US Code Collection". US Congress. Retrieved 2007-07-29. 
  12. ^ Janene Caywood (2005). "National Register of Historic Places Registration: North Rim Road, Black Canyon of the Gunnison National Park / North Rim Road Historic District/ 5MN.3522". National Park Service.  and accompanying photos
  13. ^ "Black Canyon of the Gunnison National Park : Plants". National Park Service. Retrieved 2007-07-29. 
  14. ^ Beatty, B.L., W.F. Jennings, and R.C. Rawlinson (2004, February 9). Gilia penstemonoides M.E. Jones (Black Canyon gilia): a technical conservation assessment. [Online]. USDA Forest Service, Rocky Mountain Region.
  15. ^ "Black Canyon of the Gunnison National Park : Animals". National Park Service. Retrieved 2007-07-29. 
  16. ^ "Black Canyon of the Gunnison National Park : Rock Climbing". National Park Service. Retrieved 2007-07-29. 
  17. ^ "Black Canyon of the Gunnison National Park : Kayaking". National Park Service. Retrieved 2008-03-30. 
  18. ^ "Black Canyon of the Gunnison National Park : Rafting". National Park Service. Retrieved 2008-03-30. 
  19. ^ "Gunnison Gorge National Conservation Area". Bureau of Land Management - Colorado. Archived from the original on March 25, 2008. Retrieved 2008-03-30. 

External links[edit]