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This article is about the canyon in the southwestern United States. For other Grand Canyons, see Grand Canyon (disambiguation).
Christmas Day 2006, South Rim

the canyon in america is a structure with huge pinfoldin

The Grand Canyon is a very colorful, steep-sided gorge, carved by the Colorado River in the U.S. state of Arizona. It is largely contained within the Grand Canyon National Park — one of the first national parks in the United States. President Theodore Roosevelt was a major proponent of conservation of the Grand Canyon area, and visited on numerous occasions to hunt and enjoy the scenery.

The canyon, created by the Colorado River over about 6 million years, is 277 miles (446 km) long, ranges in width from 4 to 18 miles (6.4 to 24 kilometers), and attains a depth of more than a mile (1.6 km). Nearly two billion years of the Earth's history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted.

During prehistory, the area was inhabited by Native Americans who built settlements within the canyon and its many caves. The first European known to have viewed the Grand Canyon was García López de Cárdenas from Spain, who arrived in 1540.[1] The Grand Canyon was largely unknown until after the U.S. Civil War. In 1869, Major John Wesley Powell, a one-armed Civil War veteran with a thirst for science and adventure, made the first recorded journey through the canyon on the Colorado River. He accomplished this trek with nine men in four small wooden boats, though only six men completed the journey. Powell referred to the sedimentary rock units exposed in the canyon as "leaves in a great story book".

View from the North Rim of the Grand Canyon

Geography

The Grand Canyon is a massive — in places over a mile (1,609 m) deep — 277 miles (446 km) long rift in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata. The Grand Canyon is unmatched throughout the world for the vistas it offers to visitors on the rim. It is not the deepest canyon in the world. Both the Barranca del Cobre in Northern Mexico and Hell's Canyon in Idaho are deeper. But Grand Canyon is known for its overwhelming size and its intricate and colorful landscape. Geologically it is significant because of the thick sequence of ancient rocks that are beautifully preserved and exposed in the walls of the canyon. These rock layers record much of the early geologic history of the North American continent. Grand Canyon is also one of the most spectacular examples of natural erosion in the world.

Grand Canyon seen from the South Rim, 2003.

Uplift associated with mountain building events later moved these sediments thousands of feet upward and created the Colorado Plateau. The higher elevation has also resulted in greater precipitation in the Colorado River drainage area, but not enough to change the Grand Canyon area from being semi-arid. The uplift of the Colorado Plateau is uneven, and the north-south trending Kaibab Plateau that Grand Canyon bisects is over a thousand feet higher at the North Rim (about 1,000 ft/300 m) than at the South Rim. The fact that the Colorado River flows in a curve around the higher North Rim part of the Kaibab Plateau and closer to the South Rim part of the plateau is also explained by this asymmetry. Ivo Lucchitta of the U.S. Geological Survey first suggested that, as the Colorado River developed before significant erosion of the region, it naturally found its way across or around the Kaibab Uplift by following a "racetrack" path to the south of the highest part of the plateau. Almost all runoff from the North Rim (which also gets more rain and snow) flows toward the Grand Canyon, while much of the runoff on the plateau behind the South Rim flows away from the canyon (following the general tilt). The result is deeper and longer tributary washes and canyons on the north side and shorter and steeper side canyons on the south side.

Temperatures on the North Rim are generally lower than the South Rim because of the greater elevation (averaging 8,000 ft/2,438 m above sea level).[2] Heavy rains are common on both rims during the summer months. Access to the North Rim via the primary route leading to the canyon (Arizona State Route 67) is limited during the winter season due to road closures. Views from the North Rim tend to give a better impression of the expanse of the canyon than those from the South Rim.

Geology

Main article: Geology of the Grand Canyon area

The principal consensus among geologists is that the Colorado River basin (of which the Grand Canyon is a part) has developed in the past 40 million years and that the Grand Canyon itself is probably less than five to six million years old (with most of the downcutting occurring in the last two million years). The result of all this erosion is one of the most complete geologic columns on the planet.

Looking down Bright Angel trail to the Grand Canyon. The green area is Indian Gardens and the trail continues to Phantom Ranch at the river where a suspension bridge allows access to the North Rim.

The major geologic exposures in Grand Canyon range in age from the 2 billion year old Vishnu Schist at the bottom of the Inner Gorge to the 230 million year old Kaibab Limestone on the Rim. Interestingly, there is a gap of about one billion years between the stratum that is about 500 million years old and the lower level, which is about 1.5 billion years old. That indicates a period of erosion between two periods of deposition.

Many of the formations were deposited in warm shallow seas, near-shore environments (such as beaches), and swamps as the seashore repeatedly advanced and retreated over the edge of a proto-North America. Major exceptions include the Permian Coconino Sandstone which was laid down as sand dunes in a desert and several parts of the Supai Group.

The great depth of the Grand Canyon and especially the height of its strata (most of which formed below sea level) can be attributed to 5,000 to 10,000 feet (1500 to 3000 m) of uplift of the Colorado Plateau, starting about 65 million years ago (during the Laramide Orogeny). This uplift has steepened the stream gradient of the Colorado River and its tributaries, which in turn has increased their speed and thus their ability to cut through rock (see the elevation summary of the Colorado River for present conditions).

Weather conditions during the ice ages also increased the amount of water in the Colorado River drainage system. The ancestral Colorado River responded by cutting its channel faster and deeper.

The base level and course of the Colorado River (or its ancestral equivalent) changed 5.3 million years ago when the Gulf of California opened and lowered the river's base level (its lowest point). This increased the rate of erosion and cut nearly all of the Grand Canyon's current depth by 1.2 million years ago. The terraced walls of the canyon were created by differential erosion.[3]

About one million years ago, volcanic activity (mostly near the western canyon area) deposited ash and lava over the area, which at times completely obstructed the river. These volcanic rocks are the youngest in the canyon.

Human history

Main article: History of the Grand Canyon area

The Ancestral Puebloans (The Ancient Ones, or Anasazi)

The Grand Canyon, as seen from river-level.

The Modern Hopi

See also Pueblo people.

Other cultures

European arrival and settlement

The Spanish explorers

In September 1540, under orders from the conquistador Francisco Vázquez de Coronado to search for the fabled Seven Cities of Cibola, Captain Garcia Lopez de Cardenas, along with Hopi guides and a small group of Spanish soldiers, traveled to the South Rim of the Grand Canyon between Desert View and Moran Point. Pablo de Melgrossa, Juan Galeras, and a third soldier descended some one third of the way into the Canyon until they were forced to return because of lack of water. In their report, they noted that some of the rocks in the Canyon were "bigger than the great tower of Seville."[5] It is speculated that their Hopi guides must have been reluctant to lead them to the river, since they must have known routes to the canyon floor. Afterwards, no Europeans visited the Canyon for over two hundred years.

Fathers Francisco Atanasio Domínguez and Silvestre Vélez de Escalante were two Spanish Priests who, with a group of Spanish soldiers, explored southern Utah and traveled along the North Rim of the Canyon in Glen and Marble Canyons in search of a route from Santa Fe to California in 1776. They eventually found a crossing at present-day Lees Ferry.

Also in 1776, Fray Francisco Garces, a Franciscan missionary, spent a week near Havasupai, unsuccessfully attempting to convert a band of Indians. He described the Canyon as "profound".Cite error: A <ref> tag is missing the closing </ref> (see the help page).

File:Stamp-ctc-grand-canyon-national-park.jpg
The United States government made the Grand Canyon a national park in 1919

Jacob Hamblin (a Mormon missionary) was sent by Brigham Young in the 1850s to locate easy river crossing sites in the Canyon. Building good relations with local Native Americans and white settlers, he discovered Lee's Ferry in 1858 and Pierce Ferry (later operated by, and named for, Harrison Pierce) - the only two sites suitable for ferry operation.[citation needed] He also acted as an advisor to John Wesely Powell before his second expedition to the Grand Canyon, acting as a diplomat between Powell and the local native tribes to ensure the safety of his party.

In 1857, the U.S. War Department asked Lieutenant Joseph Ives to lead an expedition to assess the feasibility of an up-river navigation from the Gulf of California. Also in a stern wheeler steamboat "Explorer", after two months and 350 miles (560 km) of difficult navigation, his party reached Black Canyon some two months after George Johnson.[citation needed] The "Explorer" struck a rock and was abandoned. Ives led his party east into the Canyon — they were the first Europeans to travel the Diamond Creek drainage and traveled eastwards along the South Rim.

  • The John Wesley Powell River Expeditions
  • The Brown-Stanton River Expedition
  • Other expeditions

Settlers in and near the canyon

Federal protection

The federal government administrators who manage park resources face many challenges. These include issues related to the recent reintroduction into the wild of the highly endangered California Condor, air tour overflight noise levels, water rights disputes with various tribal reservations that border the park, and forest fire management. The Grand Canyon National Park superintendent is Steve Martin. Martin was named superintendent on February 5, 2007 to replace retiring superintendent Joe Alston. Martin was previously the National Park Service Deputy Director and superintendent of several other national parks including Denali and Grand Teton.[6] Another recent administrative challenge involves a controversy over the sale in Park bookstores of a creationist book claiming the Grand Canyon was created by Noah's Flood in 2348 BC, which disagrees with the actual timeframe and evidence.

South Rim buildings

There are several historical buildings located along the South Rim; most are in Grand Canyon Village.

Desert View Watchtower (2004)

Buckey O'Neill Cabin was built during the 1890s by William Owen O'Neill. He built the cabin because of a copper deposit that was nearby. He had several occupations such as miner, judge, politician, author and tour guide. This cabin is the longest continually standing structure in the South Rim. It is currently used as a guest house; booking is required well in advance.

Kolb Studio was built in 1904 by brothers Ellsworth and Emery Kolb. They were photographers who made a living by photographing visitors walking down the Bright Angel Trail. In 1911, the Kolb brothers filmed their journey down the Green and Colorado Rivers. Emery Kolb showed this movie regularly in his studio until 1976, when he died at the age of 95.

The El Tovar Hotel was built in 1905 and is the most luxurious lodging on the South Rim. The hotel consists of 4 stories with a rustic chalet appearance. It was designed by Charles Whittlesley. A gift shop and restaurant are located inside the hotel.

Hopi House was built by the Hopi in 1905. It is based on structures that were built in an ancient Hopi settlement called Old Oraibi, located on the Third Mesa in eastern Arizona. It served as a residence for the Hopi Indians who sold arts and crafts to visitors in the South Rim.

Verkamp's Curios was built by John Verkamp in 1905. He sold arts and crafts as well as souvenirs. It is currently run by his descendants and stands next to the Hopi House.

Grand Canyon Railway Depot was built in 1909 and contains 2 levels. It is one of only three log-cabin-style train stations currently standing in the United States, of the fourteen ever built in the U.S. The depot is the northern terminus of the Grand Canyon Railway which begins in Williams, Arizona.

Lookout Studio was built in 1914 and is another structure that was designed by Mary Colter. Photography artwork, books, souvenirs, and rock and fossil specimens are sold here. A great view of Bright Angel Trail can be seen here.

Desert View Watchtower was built in 1932 and is one of Mary Colter's best-known works. Situated at the far eastern end of the South Rim, 27 miles (43 km) from Grand Canyon Village, the tower sits on a 7,400 foot (2,256 m) promontory. It offers one of the few views of the bottom of the Canyon and the Colorado River. It is designed to mimic an Anasazi watchtower though it is larger than existing ones.[7]

Bright Angel Lodge was built of logs and stone in 1935. Mary Colter designed the lodge and it was built by Fred Harvey. Inside the lodge is a small museum honoring Fred Harvey, who played a major role in popularizing the Grand Canyon. In the history room is a fireplace that is made of stone from the South Rim that is layered in the same sequence as in the canyon.

Weather

Weather in the Grand Canyon varies according to elevation. The forested rims are high enough to receive winter snowfall, but along the Colorado River in the Inner Gorge, temperatures are similar to those found in Tucson and other low elevation desert locations in Arizona. Conditions in the Grand Canyon region are generally dry, but substantial precipitation occurs twice annually, during seasonal pattern shifts in winter (when Pacific storms usually deliver widespread, moderate rain and high-elevation snow to the region from the west) and in late summer (a phenomenon known as the "monsoon", which delivers waves of moisture from the southeast, causing dramatic, localized thunderstorms fueled by the heat of the day).[8] Average annual precipitation on the South Rim is less than 16 inches (35 cm), with 60 inches (132 cm) of snow, the higher North Rim usually receives 27 inches (59 cm) of moisture, with a typical snowfall of 144 inches (317 cm), and Phantom Ranch, far below the Canyon's rims along the Colorado River at 2,500 feet (762 m) gets just 8 inches (17.6 cm) of rain, and snow is a rarity.

Grand Canyon, Winter 2006.

Temperatures vary wildly throughout the year, with summer highs within the Inner Gorge commonly exceeding 100°F (37.8°C) and winter minimum temperatures sometimes falling below zero degrees Fahrenheit (-17.8°C) along the canyon's rims.[8] Visitors are often surprised by these potentially extreme conditions, and this, along with the high altitude of the canyon's rims, can lead to unpleasant side effects such as dehydration, sunburn, and hypothermia. Be prepared for a variety of potential weather conditions when visiting, and keep in mind the Grand Canyon is a rugged natural feature located in a remote area subject to a wide range of environmental hazards.

Weather conditions can greatly affect hiking and canyon exploration, and visitors should obtain accurate forecasts because of hazards posed by exposure to extreme temperatures, winter storms and late summer monsoons. While the park service posts weather information at gates and visitor centers, this is a rough approximation only, and should not be relied upon for trip planning. For accurate weather in the Canyon, hikers should consult the National Weather Service's NOAA weather radio or the official NWS website.[9]

Two hikers looking down on the Grand Canyon

Air pollution

The Grand Canyon has suffered some problems with air pollution, attributed to the nearby Navajo Generating Station, a coal-burning power plant. In 1991 an agreement was reached with the Navajo Generating Station in Page, Arizona to add air pollution control devices to their smokestacks.[10] In the same year the EPA launched an investigation of the Mohave Generating Station in Laughlin, Nevada.[11]

Grand Canyon tourism

Grand Canyon National Park is one of the world’s premier natural attractions, attracting about five million visitors per year. Overall, 83% were from the United States: California (12.2%), Arizona (8.9%), Texas (4.8%), Florida (3.4%) and New York (3.2%) represented the top domestic visitors. Seventeen percent of visitors were from outside the United States; the most prominently represented nations were the United Kingdom (3.8%), Canada (3.5%), Japan (2.1%), Germany (1.9%) and The Netherlands (1.2%).[12]

Activities

Further information: [[:Template:Wikitravel]]
A view of Grand Canyon Skywalk from Outside Ledge

Aside from casual sightseeing from the South Rim (averaging 7000 feet (2100 meters) above sea level), whitewater rafting, hiking and running are especially popular. The floor of the valley is accessible by foot, muleback, or by boat or raft from upriver. Hiking down to the river and back up to the rim in one day is discouraged by park officials because of the distance, steep and rocky trails, change in elevation, and danger of heat exhaustion from the much higher temperatures at the bottom. Rescues are required annually of unsuccessful rim-to-river-to-rim travelers. Nevertheless, hundreds of fit and experienced hikers complete the trip every year.

Helicopter used for tourist flights over the Grand Canyon (photo taken during 1985)

Camping on the North and South Rims are generally restricted to established campgrounds and reservations are highly recommended, especially at the busier South Rim. All overnight camping below the rim requires a backcountry permit from the Backcountry Country Office (BCO). Each year Grand Canyon National Park receives approximately 30,000 requests for backcountry permits. The park issues 13,000 permits, and close to 40,000 people camp overnight.[13] The earliest a permit application is accepted is the first of the month, four months prior to the proposed start month. Applying as soon as allowed will improve your chances of obtaining an overnight backcountry use permit for the dates of your choice.

Tourists wishing for a more vertical perspective can board helicopters and small airplanes in Las Vegas and Phoenix for canyon flyovers. Scenic flights are no longer allowed to fly within 1500' of the rim within the national park. The last aerial video footage from below the rim was filmed in 1984. However, some helicopter flights land on the Havasupai and Hualapai Indian Reservations within Grand Canyon (outside of the park boundaries). Recently, the Hualapai Tribe opened the glass-bottomed Grand Canyon Skywalk on their property, Grand Canyon West. The Skywalk has seen mixed reviews since the site is only accessible by driving down a 14-mile dirt road, costs a minimum of $85 in total for reservation fees, a tour package and admission to the Skywalk itself and the fact that cameras are not permitted on the Skywalk at any time.

Viewing the canyon

Lipan Point is a promitory located on the South Rim. This point is located to the east of the Grand Canyon Village along the Desert View Drive. There is a parking lot for visitors who care to drive along with the Canyon's bus service that routinely stops at the point. The trailhead to the Tanner Trail is located just before parking lot. The view from Lipan Point shows a wide array of rock strata and the Unkar Creek area in the inner canyon.

Grand Canyon fatalities

Grand Canyon rescue Helicopter, 1978

About 600 deaths have occurred in the Grand Canyon since the 1870s. Some of these deaths occurred as the result of overly zealous photographic endeavors (photographers who got a little too close to the edge of the canyon to take a picture and fell), some were the result of airplane collisions within the canyon, and some visitors drowned in the Colorado River. Many hikers overestimate their fitness level, become dehydrated and confused, and must be rescued. The Park Service now posts a picture of an attractive and fit young man at several trailheads with the caption "Every year we rescue hundreds of people from the Canyon. Most of them look like him", in an attempt to discourage hikers from feats which are beyond their abilities.

According to Over the Edge: Death in the Grand Canyon, 50 fatalities have resulted from falls; 65 deaths were attributable to environmental causes, including heat stroke, cardiac arrest, dehydration, and hypothermia; 7 were caught in flash floods; 79 were drowned in the Colorado River; 242 perished in airplane and helicopter crashes (128 of them in the 1956 disaster mentioned below); 25 died in freak errors and accidents, including lightning strikes and rock falls; 47 committed suicide; and 23 were the victims of homicides.

1956 air disaster

In 1956 the Grand Canyon was the site of America's worst commercial aviation disaster at the time.

On the morning of June 30, 1956, a TWA Lockheed Super Constellation and a United Airlines Douglas DC-7 departed Los Angeles International Airport within three minutes of one another on eastbound transcontinental flights. Approximately 90 minutes later, the two propeller-driven airliners collided above the canyon while both were flying in unmonitored airspace.

The wreckage of both planes fell into the eastern portion of the canyon, on Temple and Chuar buttes, near the confluence of the Colorado and Little Colorado rivers. The disaster killed all 128 passengers and crew members aboard both planes.

This accident led to the institution of high-altitude flightways and positive control by en route ground controllers. (For more information see United Airlines Flight 718.)

See also

Notes

  1. ^ History of the Colorado Plateau
  2. ^ "Nature & Science". National Park Service. January 2007. Retrieved 2007-03-29.
  3. ^ Definition and examples of differential erosion
  4. ^ "Kaibab National Forest". USDA Forest Service. Retrieved 2007-01-04.
  5. ^ Page Stegner (1994). Grand Canyon, The Great Abyss. HarperCollins. p. 25. ISBN 0-06-258564-9.
  6. ^ "Steve Martin named Superintendent of Grand Canyon National Park" (PDF). National Park Service. Retrieved 2007-02-20.
  7. ^ Grand Canyon Desert View Watchtower
  8. ^ a b "Grand Canyon National Park Weather".
  9. ^ "Flagstaff Weather Forecast Office". National Weather Service. Retrieved 2007-01-04.
  10. ^ Trade Environment Database Projects: Grand Canyon Air Pollution
  11. ^ Final Project MOHAVE Report Fact Sheet
  12. ^ "Executive Summary of Grand Canyon Tourism" (PDF). Northern Arizona University. Retrieved 2007-01-04.
  13. ^ Grand Canyon Backcountry Permit Page

References

  • George Wuerthner (1998). Grand Canyon: A Visitor's Companion. Stackpole Books.
  • Joseph Wood Krutch (1957). Grand Canyon: Today and All Its Yesterdays.
  • Stephen J. Pyne (1998). How the Canyon Became Grand. Penguin.
  • L. Greer Price (1999). An introduction to Grand Canyon Geology. Grand Canyon Association. ISBN 0-938216-68-6.
  • Michael F. Anderson (2001). Along the Rim. Grand Canyon Association. ISBN 0-938216-75-9.
  • Christa Sadler (2006). Life in Stone. Grand Canyon Association. ISBN 0-938216-81-3.
  • Thomas M. Myers and Michael P. Ghiglieri (2001). Over the Edge: Death in Grand Canyon. Puma Press. ISBN 0-9700973-1-X.
  • Macarthur Job (2001). Air Disaster Volume 4: The Propeller Era. Aerospace Publications. ISBN 1-875671-48-X.
  • Edward Dolnick (2001). Down the Great Unknown : John Wesley Powell's 1869 Journey of Discovery and Tragedy Through the Grand Canyon. HarperCollins.
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36°06′N 112°06′W / 36.1°N 112.1°W / 36.1; -112.1

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