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Grand Canyon - Geography, Geology, Human history, Recent history, Activities, Grand Canyon Visitors, Grand Canyon Fatalities

Enormous gorge in NW Arizona, USA; 349 km/217 mi long; 8–25 km/5–15 mi wide from rim to rim; maximum depth c.1900 m/6250 ft; the result of large-scale erosion by the Colorado R, exposing hundreds of millions of years of geological formations; parts of the side walls have formed isolated towers (‘temples’) due to stream erosion (best known are Vishnu Temple, Shiva Temple, Wotan's Throne); located in Grand Canyon National Park (4931 km²/1903 sq mi); one of the main US tourist attractions.

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

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 mountain lions 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 (1,600 m).

The first recorded sighting of the Grand Canyon by a European was in 1540, García López de Cárdenas from Spain.

Geography

The Grand Canyon is very deep - in places over a mile (1 600 m) deep - 277 miles (446 km) long cut in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata. At the point where the river crosses the Grand Wash Fault (near Lake Mead) the Canyon ends. 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, resulting in the North rim of the Grand Canyon being over a thousand feet (about 300 meters) higher than the South rim. Almost all runoff from the plateau behind 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 much greater erosion and thus faster widening of the canyon and its tributary canyons north of the Colorado River.

Temperatures on the North rim are generally lower than the South rim because of the greater elevation (8000 feet/2438 meters above sea level). Views from the North rim tend to give a better impression of the expanse of the canyon rather than the views from the South Rim.

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Geology

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 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.

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).

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.

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.

Human history

Main article: History of the Grand Canyon area

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 The Bright Angel Site Ancient Pueblo peoples leave the Canyon Beamer's Cabin The Beamers back windo

The Modern Hopi (see also Pueblo people)

Other cultures

The Cohonina 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)

European discovery and settlement

The Spanish Explorers

View from the South Rim View from the South Rim on the Kaibab Trail. View from the North Rim at sunset

In September 1540, under orders from the conquistador Francisco Vasquez 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.

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.

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 .

Jacob Hamblin (a Mormon missionary) was sent by Brigham Young in the 1850's to locate easy river crossing sites in the Canyon. 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. Emmett Charles Spencer Phantom Ranch David Rust Mary Colter Grand Canyon Village Ralph H. The Grand Canyon National Park superintendent is Mr. Joe Alston who was previously the superintendent of Glen Canyon National Recreation Area (Lake Powell. Glen Canyon lies to the North and East of Grand Canyon on the Arizona/Utah Border.

Recent history

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

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.

Activities

Aside from casual sightseeing from the South Rim (averaging 7000 feet/2134 m above sea level), whitewater rafting, hiking and running are especially popular.

The canyon is extremely popular with endurance athletes, who regularly run across it.

Grand Canyon South Rim

Grand Canyon South Rim at Sunrise

The Grand Canyon from inside

The Grand Canyon as seen from Earth orbit.

Two hikers looking down on the Grand Canyon

Grand Canyon from Moran Point

Grand Canyon backcountry

Grand Canyon backcountry

Grand Canyon backcountry

Grand Canyon from Tiyo Point

Sunrise at the Grand Canyon

The Grand Canyon

Sunset seen from South rim

The United States government made the Grand Canyon a national park in 1919

Grand Canyon South Rim at Sunset

View from Lipan Point at dawn

Grand Canyon Visitors

Grand Canyon National Park is one of the world’s premier natural attractions, attracting about five million visitors per year arriving from all 50 U.S. states and Puerto Rico and internationally.

Grand Canyon Fatalities

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.

According to Over the Edge: Death in the Grand Canyon, 50 fatalities have resulted from falls;

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