The Grand Canyon is a steep-sided gorge carved by the
Colorado River in the United States 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 preservation of the
Grand Canyon area, and visited on numerous occasions to hunt and
enjoy the scenery.
Longstanding scientific consensus has been
that the canyon was created by the Colorado River over a six
million year period. The canyon is 277 miles (446 km) long,
ranges in width from 4 to 18 miles (6.4 to 29 km) and attains a
depth of over a mile (1.83 km)(6000 feet).[1]
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. The "canyon started from the west, then
another formed from the east, and the two broke through and met
as a single majestic rent in the earth some six million years
ago. [...] The merger apparently occurred where the river today,
coming from the north, bends to the west, in the area known as
the Kaibab Arch."[2]
Prior to European emigration, the area was inhabited by
Native Americans who built settlements within the canyon and its
many caves. The Pueblo people considered the Grand Canyon ("Ongtupqa"
in Hopi language) a holy site and made pilgrimages to it.
The first European known to have viewed the Grand Canyon was
García López de Cárdenas from Spain, who arrived in 1540.[3]
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. Powell
referred to the sedimentary rock units exposed in the canyon as
"leaves in a great story book".
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The landscape of the Grand Canyon |
Geography
The Grand Canyon is a massive rift in the Colorado Plateau
that exposes uplifted Proterozoic and Paleozoic strata and is
also one of the six distinct physiographic sections of the
Colorado Plateau province. 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 — Cotahuasi
Canyon (11598 feet or 3535 m) and Colca Canyon (10499 feet or
3200 m), both in Arequipa, Peru, and Hell's Canyon (7,993 feet
or2436 m) on the Oregon-Idaho border, are all Longstanding
scientific consensus has been that the canyon was created by the
Colorado River over a six million year period. The canyon is 277
miles (446 km) long, ranges in width from 4 to 18 miles (6.4 to
29 km) and attains a depth of over a mile(1.83 km)(6000 feet)[4].
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. The "canyon started from the west, then
another formed from the east, and the two broke through and met
as a single majestic rent in the earth some six million years
ago. [...] The merger apparently occurred where the river today,
coming from the north, bends to the west, in the area known as
the Kaibab Arch."[2]
l deeper — but Grand Canyon is known for its overwhelming size
and its intricate and colourful 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.
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).[5]
Heavy rains are common on both rims during the summer months.
Access to the North Rim via the primary route leading to the
canyon (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
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. A recent study places the origins
of the canyon beginning some 17 million years ago. Previous
estimates had placed the age of the canyon at 5 to 6 million
years. The study, which was published in 2008 in the journal
Science utilized uranium-lead dating to analyze calcite deposits
found on the walls of nine caves throughout the canyon.
[6]
There is a substantial amount of controversy because this
research suggests a such substantial departure from prior widely
supported scientific consensus.[7]
The result of all this erosion is one of the most complete
geologic columns on the planet.
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 most geologists interpret as an
aeolian sand dune deposit 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.[8]
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
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
Other cultures
- The Cohonina[9]
- 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 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."[10]
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 Native Americans. He described the Canyon as
"profound".[10]
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.[11]
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 Hope Dog in 1858 and Pierce Ferry (later
operated by, and named for, Harrison Pierce) - the only two
sites suitable for ferry operation.
He also acted as an advisor to John Wesley 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 Edward Fitzgerald Beale superintendent of an
expedition to survey a wagon road along the 35th parallel from
Fort Defiance to the Colorado river led a small party of men in
search of water on the Coconino plateau on the south rim of the
Grand Canyon. On September 19th near present day National Canyon
they came upon what May Humphreys Stacey described in his
journal as "...a wonderful canyon four thousand feet deep.
Everyone (in the party) admitted that he never before saw
anything to match or equal this astonishing natural curiosity."
Also 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.
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.
In 1858, John Strong Newberry became probably the first
geologist to visit the Grand Canyon.
In 1869, Major John Wesley Powell led the first expedition
down the Grand Canyon.
- The Brown-Stanton River Expedition
- Other expeditions
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 French (17th of
John Lee's 19 wives), J. S. Emmett, Charles Spencer
- Phantom Ranch: David Rust, Mary Colter
- Grand Canyon Village: Ralph H. Cameron
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.[12]
Federal officials started a flood in the Grand Canyon in hopes
of restoring its ecosystem on March 5, 2008. The canyon's
ecosystem was permanently changed after the construction of the
Glen Canyon Dam in 1963.[13]
South Rim buildings
There are several historical buildings located along the
South Rim; most are in Grand Canyon Village.
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. Today the
building serves as an art gallery and exhibit.
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 Mary Jane Colter 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. While it is commonly said that this depot
building is one of only three log-cabin-style train stations
currently standing out of fourteen supposedly ever built in the
U.S., this claim has never been verified. This claim originated
in a 1985 document written by Gordon Chappell entitled
"Statement on Architectural and Historic Significance" and is
currently repeated, without verification, by newspapers,
magazines and on-line articles, including ones appearing on the
National Park Service website. 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.[14]
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).[15]
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. The weather is different on the north rim and south rim.
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.[15]
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.[16]
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.[17]
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%).[18]
Activities
Aside from casual sightseeing from the South Rim (averaging
7000 feet (2100 m) 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
travellers. Nevertheless, hundreds of fit and experienced hikers
complete the trip every year.
Camping on the North and South Rims is generally restricted
to established campgrounds and reservations are highly
recommended, especially at the busier South Rim. There is at
large camping available along many parts of the North Rim
managed by Kaibab National Forest. Keep in mind North Rim
campsites are only open seasonally due to road closures from
weather and winter snowpack. 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.[19] 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.
If you are unable to secure a permit from the Grand Canyon
Backcountry Office, or you are not comfortable hiking the Canyon
on your own you can go with a professional guide.
The Coconino Canyon Train is another option for those seeking
to take in a more leisurely view of the canyon. It is a
90-minute ride that originates in Grand Canyon National Park at
the old Grand Canyon Depot and travels 24 miles through the
canyon landscapes. The train is made up of 1923 Pullman cars and
runs on tracks built in the 1800s.
[20]
Tourists wishing for a more vertical perspective can board
helicopters and small airplanes in Las Vegas, Phoenix and Grand
Canyon National Park Airport (seven miles from the South Rim)
for canyon flyovers. Scenic flights are no longer allowed to fly
within 1500' of the rim within the national park because of a
late 90s crash. 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
(23 km) 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. The Skywalk is located 242 miles from the
South Rim National Park. Many people mistake the west side of
the park by Hermit's Rest as the location of the Skywalk.
Viewing the canyon
Lipan Point is a promontory 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 the parking lot. The view from Lipan Point shows a
wide array of rock strata and the Unkar Creek area in the inner
canyon.
Perhaps the most heart-stopping view of the canyon is had
from the Toroweap Overlook (Tuweep) situated 3000 vertical feet
above the Colorado River, about 50 miles downriver from the
South Rim and 70 upriver from the Grand Canyon Skywalk. This
region — “One of the most remote in the United States” according
to the National Park Service — is reached only by one of three
lengthy dirt tracks, that start from St. George, Utah, Colorado
City or near Pipe Spring National Monument (both in Arizona).
These roads traverse wild, uninhabited land for 97, 62 and 64
miles respectively. A visit to this area can be challenging, but
rewarding. The Park Service manages the area for its primitive
values and, therefore, improvements and services are minimal.
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 endeavours, 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 the deadliest
commercial aviation disaster in the United States 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 flight
ways and positive control by en route ground controllers.
Evacuation
Canyon tourists and residents of Supai, a town located in the
bottom of the canyon, were evacuated from the Supai area on 17
and August 18, 2008[21]
due to a break in the earthen Redlands Dam, located upstream of
Supai, after a night of heavy rainfall. Evacuees were taken to
Peach Springs, Arizona.[22]
More heavy rains were expected and a flash flood warning was put
into effect, necessitating the evacuation, according to the
Grand Canyon National Park Service.[23]
The floods were significant enough to attract coverage from
international media.[22]
