The Grand Canyon

The Grand Canyon is a colorful, steep-sided gorge, carved by the Colorado River, in northern Arizona. The canyon is one of the seven natural wonders of the world and is largely contained in 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 breathtaking 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 4 to 18 miles (6 to 29 kilometers) and attains a depth of more than a mile (1,600 m). Nearly 2000 million 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 Grand Canyon was first seen by a European in 1540, García López de Cárdenas from Spain. The first scientific expedition to the canyon was led by U.S. Major John Wesely Powell in the late 1870s. Powell referred to the sedimentary rock units exposed in the canyon as "leaves in a great story book." However, long before that, the area was inhabited by Native Americans who built settlements in the canyon walls.

Geography

The Grand Canyon is a very deep - in places even a mile deep - 277 mile (446 km) long cut in the Colorado Plateaus that exposes uplifted Proteozoic and Paleozoic strata. The exposed strata are gradually revealed by the gentle incline beginning at Lee's Ferry and continuing to Phantom Ranch. At the point where the river crosses the Grand Wash Fault (near Lake Mead) the Canyon ends.

Uplift associated with plate tectonics-caused mountain building events later moved these sediments thousands of feet upward and created the Colorado Plateaus. 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. Landslides and other mass wasting events then caused headward erosion and stream capture - all of which tend to increase the depth and width of canyons in arid environments.

The uplift of the Colorado Plateaus is uneven, resulting in the North Rim of the Grand Canyon being over a thousand feet (about 300 meters) higher than the South Rim. The fact that the Colorado River flows closer to the South Rim is also explained by this asymmetrical uplift. 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 m above sea level). Heavy snowfall is common during the winter months. Views from the North Rim tend to give a better impression of the expanse of the canyon rather than the views down which characterize the South Rim.

The Havasupai Indian Reservation is in a large tributary canyon on the south side of the Colorado River; it is administered by the Havasupai Indian Tribe.

Geology



The Grand Canyon as seen from Earth orbit. NASA

Geology of the Grand Canyon areaThe major sedimentary rock units exposed in the Grand Canyon range in age from the 2000 million year old Vishnu Schist at the bottom of the Inner Gorge to the 230 million year old Kaibab Limestone on the Rim. Most 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. The major exception being the Cococino Sandstone which was laid down as sand dunes in a desert.

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 5000 to 10,000 feet (1500 to 3000 m) of uplift of the Colorado Plateaus starting about 65 million years ago (which occurred in a series of uplift events rather than a continuous rise). 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.

The Colorado River drainage (of which the Grand Canyon is a part) has developed in the past 40 million years and 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. The river is still actively cutting deeper and is thus exposing older and older rock.

Wetter conditions during 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.

Then 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.

A million years ago volcanic activity (mostly near the western canyon area) deposited ash and lava over the area which at times even dammed the Colorado. These are the youngest rocks in the park.

With its current stream gradient, the Colorado River should cut another 1200 to 2000 feet (370 to 600 meters) into the rock of the canyon before reaching its base level.

History of the Grand Canyon area

The known history of the Grand Canyon area stretches back 10,500 years when the first evidence for human presence in the area started. Native Americans have been living at Grand Canyon and in the area now covered by Grand Canyon National Park for at least the last 4,000 of those years. Anasazi, first as the Basketmaker culture and later as the more familiar Puebleoans, developed from the Desert Culture as they became less nomadic and more dependent on agriculture. A similar culture, the Cohonina, also lived in the canyon area.

Drought in the late 13th century was the likely cause for both cultures to move on. Other cultures followed, including the Paiutes, Cerbat, and the Navajo, only to be later forced onto reservations by the United States Government.

Under direction by conquistador Francisco Vasquez de Coronado to find the fabled Seven Cities of Cibola, Captain Garcia Lopez de Cardenas led a party of Spanish soldiers with Hopi guides to the Grand Canyon in September of 1540. Not finding what they were looking for, they left. Over 200 years passed before two Spanish priests became the second party of non-Native Americans to see the canyon.

In 1869, U.S. Army Major John Wesley Powell led the Powell Expeditions through the canyon on the Colorado River. This and later study by geologists uncovered the geology of the Grand Canyon area and helped to advance that science.

In the late 19th century there was interest in the region because of its promise of mineral resources‹mainly copper and asbestos. The first pioneer settlements along the rim came in the 1880s.

Early residents soon discovered that tourism was destined to be more profitable than mining, and by the turn of the century Grand Canyon was a well-known tourist destination. Most visitors made the grueling trip from nearby towns to the South Rim by stagecoach.

In 1901 the Grand Canyon Railway was opened from Williams, Arizona, to the South Rim, and the development of formal tourist facilities, especially at Grand Canyon Village, increased dramatically. The Fred Harvey Company developed many facilities at the Grand Canyon, including the luxury El Tovar Hotel on the South Rim in 1905 and Phantom Ranch in the Inner Gorge in 1922.

Although first afforded Federal protection in 1893 as a forest reserve and later as a U.S. National Monument, Grand Canyon did not achieve U.S. National Park status until 1919, three years after the creation of the National Park Service. Today, Grand Canyon National Park receives about five million visitors each year, a far cry from the annual visitation of 44,173 in 1919.

Native American inhabitation

Current archaeological evidence suggests that humans have inhabited the Grand Canyon area as far back as 4,000 years and at least were passers through for 6,500 years before that. Radiocarbon dating of artifacts found in limestone caves in the inner canyon indicate ages of 3,000 to 4,000 years.

In the 1930s artifacts consisting of split-twig animal figurines were found in the Redwall Limestone cliffs of the Inner Gorge that were dated in this range. These animal figurines are a few inches (7 to 8 cm) in height and made primarily from twigs of willow or cottonwood. This find along with other evidence suggests these inner canyon dwellers were part of Desert Culture; a group of seminomatic hunter-gatherer Native Americans.

The Basketmaker Anasazi (also called the Histatsinom, "people who lived long ago") evolved from the Desert Culture sometime around 500 BCE. This group inhabited the rim and inner canyon and survived by hunting and gathering along with some limited agriculture. Noted for their basketmaking skills (hence their name), they lived in small communal bands inside caves and circular mud structures called pithouses. Further refinement of agriculture and technology led to a more sedentary and stable lifestyle for the Anasazi starting around 500 CE. Contemporary with the flourishing of Azasazi culture, another group, called the Cohonina lived west of the current site of Grand Canyon Village.

Anasazi in the Grand Canyon area started to use stone in addition to mud and poles to erect above-ground houses sometime around 800 CE. Thus the Pueblo period of Anasazi culture was initiated. In summer, the Puebleoans migrated from the hot inner canyon to the cooler high plateaus and reversed the journey for winter. Large graineries and multi-room pueblos survive from this period.

There are around 2,000 known Anasazi archaeological sites in park boundaries. The most accessible site is Tusayan Pueblo, which was constructed sometime around 1185 and housed 30 or so people.

Anasazi food storage building ruins at Tusayan Pueblo.Large numbers of dated archaeological sites indicate that the Anasazi and the Cohonina flourished until about 1200 CE. Something happened a hundred years after that, however, that forced both of these cultures to move away.

Several lines of evidence led to a theory that climate change caused a severe drought in the region from 1276 to 1299, forcing these agriculture-dependent cultures to move on. Many Anasazi relocated to the Rio Grande and the Little Colorado River drainages, where their descendants, the Hopi and the 19 Pueblos of New Mexico, now live. The Hopi people believe they emerged from the canyon and that their spirits rest here.

For approximately one hundred years the canyon area was uninhabited by humans. Paiutes from the east and Cerbat from the west were the first humans to reestablish settlements in and around the Grand Canyon. The Pauite settled the plateaus north of the Colorado River and the Cerbat built their communities south of the river, on the Coconino Plateau. Sometime in the 15th century the Navajo, or the Dine, arrived in the area.All three cultures were stable until the United States Army moved them to Indian reservations in 1882 as part of the removal efforts that ended the Indian Wars. The Havasupai and Hualapai are descended from the Cerbat and still live in the immediate area. Havasu Village, in the western part of the current park, is likely one of the oldest continuously-occupied settlements in the contiguous United States. Adjacent to the eastern part of the park is the Navajo Nation, the largest reservation in the United States.

Anasazi in the Grand Canyon area started to use stone in addition to mud and poles to erect above-ground houses sometime around 800 CE. Thus the Pueblo period of Anasazi culture was initiated. In summer, the Puebleoans migrated from the hot inner canyon to the cooler high plateaus and reversed the journey for winter. Large graineries and multi-room pueblos survive from this period. There are around 2,000 known Anasazi archaeological sites in park boundaries. The most accessible site is Tusayan Pueblo, which was constructed sometime around 1185 and housed 30 or so people.Anasazi food storage building ruins at Tusayan Pueblo.

Large numbers of dated archaeological sites indicate that the Anasazi and the Cohonina flourished until about 1200 CE. Something happened a hundred years after that, however, that forced both of these cultures to move away. Several lines of evidence led to a theory that climate change caused a severe drought in the region from 1276 to 1299, forcing these agriculture-dependent cultures to move on.

Many Anasazi relocated to the Rio Grande and the Little Colorado River drainages, where their descendants, the Hopi and the 19 Pueblos of New Mexico, now live. The Hopi people believe they emerged from the canyon and that their spirits rest here.For approximately one hundred years the canyon area was uninhabited by humans.

Paiutes from the east and Cerbat from the west were the first humans to reestablish settlements in and around the Grand Canyon. The Pauite settled the plateaus north of the Colorado River and the Cerbat built their communities south of the river, on the Coconino Plateau.

Sometime in the 15th century the Navajo, or the Dine, arrived in the area.All three cultures were stable until the United States Army moved them to Indian reservations in 1882 as part of the removal efforts that ended the Indian Wars.

The Havasupai and Hualapai are descended from the Cerbat and still live in the immediate area. Havasu Village, in the western part of the current park, is likely one of the oldest continuously-occupied settlements in the contiguous United States. Adjacent to the eastern part of the park is the Navajo Nation, the largest reservation in the United States.


Historic Exploration
The Spanish

The first documented case of Europeans seeing the Grand Canyon occurred in September of 1540. That year Hopi guides led a group of 13 Spanish soldiers under Captain Garcia Lopez de Cardenas to find the fabled Seven Cities of Cibola for his superior officer, the conquistador Francisco Vasquez de Coronado.

The group arrived at South Rim of the Grand Canyon between Desert View and Moran Point and saw a river below. Pablo de Melgrossa, Juan Galeras and a third soldier descended 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.

Cardenas greatly underestimated the width of the river below to be 10 feet (3 m). No Europeans visited the canyon for over 200 years

Fathers Francisco Atanasio Dominguez and Silvestre Velez de Escalante were two Spanish Priests who, with a group of Spanish soldiers, explored southern Utah. The group traveled along the North Rim of the Canyon in Glen and Marble Canyons in search of a route from Santa Fe, New Mexico, to Monterey, California, in 1776.

The Americans

James Ohio Pattie and a group of American trappers and mountain men were probably the next Europeans to reach the Canyon in 1826. There is little in terms of documentation to support this, however.

The signing of the Treaty of Guadalupe Hidalgo in 1848 ceded the Grand Canyon region to the United States. Jules Marcou of the Pacific Railroad Survey made the first geologic observations of the canyon and surrounding area in 1856.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. George Johnson lead an expedition by stern wheeler steam boat that reached Black Canyon in 1857.
The 54 foot (16 m) paddle wheeler Explorer in the Lt. Joseph Ives expedition up the Colorado River. Period engraving.A U.S. War Department expedition led by Lt. Joseph Ives was launched in 1857 to investigate the area's potential for natural resources, to find railroad routes to the west coast, and assess the feasibility of an up-river navigation route from the Gulf of California.

The group traveled in a stern wheeler steamboat named Explorer. After two months and 350 miles (560 km) of difficult navigation, his party reached Black Canyon some two months after George Johnson. In the process, the Explorer struck a rock and was abandoned. The group later traveled eastwards along the South Rim of the Grand Canyon.

A man of his time, Ives discounted his own impressions on the beauty of the canyon and declared it and the surrounding area as "altogether valueless", remarking that his expedition would be "the last party of whites to visit this profitless locality".

Attached to Ives' expedition was geologist John Strong Newberry who had a very different impression of the canyon. After returning, Newberry convinced fellow geologist John Wesley Powell that a boat run through the Grand Canyon to complete the survey would be worth the risk.

Powell was a major in the United States Army and was a veteran of the American Civil War, a conflict that cost him his right forearm in the Battle of Shiloh.John Wesley Powell in 1869.

More than a decade after the Ives Expedition and with help from the Smithsonian Institution, Powell led the first of the Powell Expeditions to explore the region and document its scientific offerings.

On May 24, 1869, the group of nine men set out from Green River Station in Wyoming down the Colorado River and through the Grand Canyon. This first expedition was poorly-funded and consequently no photographer or graphic artist was included. While in the Canyon of Lodore one of the group's four boats capsized, spilling most of their food and much of their scientific equipment into the river. This shortened the expedition to one hundred days.

Tired of being constantly cold, wet and hungry and not knowing they had already passed the worst rapids, three of Powell's men climbed out of the canyon in what is now called Separation Canyon.

Once out of the canyon, all three were killed by Shivwits band Paiutes who thought they were miners that recently molested a female Shivwit. All those who stayed with Powell survived and that group successfully ran most of the canyon.

Two years later a much better-funded Powell-led party returned with redesigned boats and a chain of several supply stations along their route. This time, photographer E.O. Beaman and 17-year-old artist Frederick Dellenbaugh were included. Beaman left the group in January 1872 over a dispute with Powell and his replacement, James Fennemore, quit August that same year due to poor health, leaving boatman Jack Hillers as the official photographer (nearly one ton of photographic equipment was needed on site to process each shot).

Famed painter Thomas Moran joined the expedition in the summer of 1873, after the river voyage and thus only viewed the canyon from the rim. His 1873 painting "Chasm of the Colorado" was bought by the United States Congress in 1874 and hung in the lobby of the Senate.

The Powell expeditions systematically cataloged rock formations, plants, animals, and archaeological sites. Photographs and illustrations from the Powell expeditions greatly popularized the canyonland region of the southwest United States, especially the Grand Canyon (knowing this Powell added increasing resources to that aspect of his expeditions).

Powell later used these photographs and illustrations in his lecture tours, making him a national figure. Rights to reproduce 650 of the expeditions' 1,400 stereographs were sold to help fund future Powell projects. In 1881 he became the second director of the U.S. Geological Survey.Geologist Clarence Dutton (photo) followed up on Powell's work in 1880­1881 with the first in-depth geological survey of the newly-formed U.S. Geological Survey. Painters Thomas Moran and William Henry Holmes accompanied Dutton, who was busy drafting detailed descriptions of the area's geology.

The report that resulted from the team's effort was titled A Tertiary History of The Grand Canyon District, with Atlas and was published in 1882.

This and later study by geologists uncovered the geology of the Grand Canyon area and helped to advance that science. Both the Powell and Dutton expeditions helped to increase interest in the canyon and surrounding region.

Prospectors in the 1870s and 1880s staked mining claims in the canyon. They hoped that previously-discovered deposits of asbestos, copper, lead, and zinc would be profitable to mine. Access to and from this remote region and problems getting ore out of the canyon and its rock made the whole exercise not worth the effort. Most moved on, and some stayed to seek profit in the tourist trade. Their activities improved pre-existing Indian trails, such as Bright Angel Trail.

Tourism - Transportation

A rail line to the largest city in the area, Flagstaff, was completed in 1882 by the Santa Fe Railroad. Stage coaches started to bring tourists from Flagstaff to the Grand Canyon the next year‹an eleven-hour journey. Tourism greatly increased in 1901 when a spur of the Santa Fe Railroad to Grand Canyon Village was completed.

The first scheduled train with paying passengers of the Grand Canyon Railway arrived from Williams, Arizona, on September 17th that year. The 64 mile (103 km) long trip cost $3.95, and naturalist John Muir later commended the railroad for its limited environmental impact.Competition with the automobile (see below) forced the Santa Fe Railroad to cease operation of the Grand Canyon Railway in 1968 (only three passengers were on the last run).

The railway was restored and reintroduced in 1990 and has since carried hundreds of passengers a day.

The first automobile was driven to the Grand Canyon in 1902. Oliver Lippincott from Los Angeles, California, drove his Toledo Automobile Company-built car to the South Rim from Flagstaff. Lippincott, a guide and two writers set out on the afternoon of January 4 that year anticipating a seven-hour journey.

Two days later, the hungry and dehydrated party arrived at their destination; the countryside was just too rough for the 10 horsepower (7 kW) auto. A three day drive from Utah in 1907 was required to reach the North Rim for the first time.Trains, however, remained the preferred way to travel to the canyon until they were surpassed by the auto in the 1930s.

By the early 1990s more than a million automobiles per year visited the park. Air pollution from those vehicles and wind-blown pollution from Flagstaff and even the Las Vegas area has reduced visibility in the Grand Canyon and vicinity.West Rim Drive was completed in 1912. In the late 1920s the first rim to rim access was established by the North Kaibab suspension bridge over the Colorado River.

Paved roads did not reach the less popular and more remote North Rim until 1926, and that area, being higher in elevation, is closed due to winter weather from November to April. Construction of a road along part of the South Rim was completed in 1935.

Activities

New hiking trails, along old Indian trails, were established during this time as well. The world famous mule rides down Bright Angel Trail were mass-marketed by the El Tovar Hotel. By the early 1990s, 20,000 people per year made the journey into the canyon by mule, 800,000 by hiking, 22,000 passed through the canyon by raft, and another 700,000 tourists fly over it in air tours (airplane and helicopter). Overflights were limited to a narrow corridor in 1956 after two planes crashed, killing all on board.

In 1991 nearly 400 search and rescues were performed, mostly for unprepared hikers who suffered from heat exhaustion and dehydrated while ascending from the canyon (normal exhaustion and injured ankles are also common in rescuees). An IMAX theater just outside the park shows a reenactment of the Powell Expedition.

The Kolob Brothers, Emery and Ellsworth, built a photographic studio on the South Rim at the trailhead of Bright Angel Trail in 1904. Hikers and mule caravans intent on descending down the canyon would stop at the Kolob Studio to have their photos taken. The Kolob Brothers processed the prints before their customers returned to the rim. Using the newly-invented Pathe Bray camera in 1911­12, they became the first to make a motion picture of a river trip through the canyon that itself was only the eighth such successful journey.

From 1915 to 1975 the film they produced was shown twice a day to tourists with Emery Kolob at first narrating in person and later through tape (a feud with Fred Harvey prevented pre-1915 showings).

References - Links - Images Wikipedia



Grand Canyon Glass Bridge Rolled Out National Geographic - March 9, 2007

The all-glass, balcony-like "Skywalk" extends over the edge of the Grand Canyon, 4,000 feet (1,200 meters) above the Colorado River. Grand Canyon West will be on the western edge of Grand Canyon National Park, about 120 miles (about 200 kilometers) from Las Vegas. But perhaps not even the Las Vegas Strip's over-the-top attractions will be a match for this glass-bottom walkway over the world's biggest gorge.

Reference : Crystallink