Grand Canyon

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Coordinates: 36°13′38″N, 112°20′7″W 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 the Grand Canyon area, visiting on numerous occasions to hunt and enjoy the scenery.

The canyon, created by the Colorado River cutting a channel over millions of years, is about 277 miles (446 km) long, ranges in width from 0.25 to 15 miles (0.4 to 24 kilometers), and attains a depth of more than a mile (1 km). Nearly two billion years of the Earth's history has been exposed as the Colorado River and its tributaries cut through layer after layer of sediment as the Colorado Plateaus have uplifted.

The first recorded sighting of the Grand Canyon by a European was in 1540, García López de Cárdenas from Spain.^[1] 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 a pioneering journey through the canyon on the Colorado River. He accomplished this with nine men in four small wooden boats, though only six men completed the journey. His party was, as far as we know, the first ever to make such a trip. Powell referred to the sedimentary rock units exposed in the canyon as "leaves in a great story book". Long before that, the area was inhabited by Native Americans who built settlements within the canyon walls and its many caves.

View from the North Rim of the Grand Canyon.

[edit] Geography

The Grand Canyon is a massive — in places over a mile (1609 m) deep — 277 miles (446 km) long rift in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata. 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 300 meters) 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 4000 feet (1220 meters)^[2] above sea level). 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.

[edit] 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. 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 Plateaus, 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.

[edit] Human history

Main article: History of the Grand Canyon area

[edit] The Ancestral Puebloans (The Ancient Ones, or Anasazi)

• The Basketmakers
• The Pueblo Anasazi
• Ancient Puebloan Occupation of the Grand Canyon
  • Nankoweap Canyon
  • The Unkar Delta (see Geology of the Grand Canyon area)
  • The Bright Angel site
• Ancient Pueblo Peoples leave the Canyon
  • Beamer's Cabin
    • The Beamers Back Window

The Grand Canyon, as seen from river-level.

[edit] The Modern Hopi (see also Pueblo people)

[edit] Other cultures

• The Cohonina ^[4]
• The Sinagua
• The Pai (The People)
• The Hualapai (The People of the Pine Trees)
• The Havasupai (The People of the blue-green water)
• The Paiutes (The Water People)
• The Dineh (The People)

[edit] European arrival and settlement

[edit] 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.^{[citation needed]} 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. 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.^{[citation needed]}

[edit] American Exploration

James Ohio Pattie, along with a group of American trappers and mountain men, was probably the next European to reach the Canyon in 1826, although there is little documentation to support this.^[5]

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]}

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

[edit] Settlers in and near the Canyon

• Miners: "Captain" John Hance, William W. Bass, Louis Boucher "The Hermit", Seth Tanner, Charles Spencer, D. W. "James" Mooney
• Lees Ferry: John Doyle Lee, Emma Lee (17th of John Lee's 19 wives), J. S. Emmett, Charles Spencer
• Phantom Ranch: David Rust, Mary Colter
• Grand Canyon Village: Ralph H. Cameron

[edit] Federal protection

Many challenges face the federal government administrators who manage park resources. 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.

[edit] 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 1890's 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 and 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 of all lodging located in 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 only 1 of 3 log cabin style train stations currently standing in the United States and 1 of 14 ever built in the country. 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 and 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 in 1935 and consisted of logs and stone. 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 and it's layered in the same sequence as the canyon.

[edit] 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 degrees F (37.8 C) and winter minimum temperatures sometimes falling below zero 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

[edit] 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]

[edit] Grand Canyon visitors

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]

[edit] Activities

For more information on activities see

• Grand Canyon National Park Service
• Grand Canyon travel guide from Wikitravel

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.

[edit] 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, 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 "Many 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.

[edit] 1956 Air Disaster

On 30 June 1956, United Airlines Flight 718 and TWA flight 2 collided in mid-air over the Grand Canyon. The wreckage of both planes fell into the eastern portion of the canyon near the confluence of the Colorado and Little Colorado rivers. This incident led to the institution of high-altitude flightways and positive control by en route ground controllers. (For more information see United Airlines Flight 718.)

[edit] See also

• List of Colorado River rapids and features
• Grand Canyon National Park
• List of trails in Grand Canyon National Park
• Colca Canyon
• Grand Canyon Dories

[edit] Notes

[edit] References

[edit] External links

Wikimedia Commons has media related to:

Grand Canyon

• Grand Canyon National Park Service
• Grand Canyon travel guide from Wikitravel
• Grand Canyon Semester: The Oldest Classroom on Earth
• Grand Canyon 3-D perspective View looking Southwesterly showing North Rim and Canyon.

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