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106-817: The Colorado Plateau is largely made up of high desert, with scattered areas of forests. In the south-west corner of the Colorado Plateau lies the Grand Canyon of the Colorado River. Much of the Plateau's landscape is related to the Grand Canyon in both appearance and geologic history. The nickname "Red Rock Country" suggests the brightly colored rock left bare to the view by dryness and erosion. Domes , hoodoos , fins , reefs , river narrows , natural bridges , and slot canyons are only some of

212-612: A continental margin throughout the late Precambrian and most of the Paleozoic era. Igneous rocks injected millions of years later form a marbled network through parts of the Colorado Plateau's darker metamorphic basement. By 600 million years ago North America had been leveled off to a remarkably smooth surface. Throughout the Paleozoic Era, tropical seas periodically inundated the Colorado Plateau region. Thick layers of limestone, sandstone, siltstone, and shale were laid down in

318-476: A sipapu . In September 1540, under orders from the conquistador Francisco Vázquez de Coronado to search for the fabled Seven Cities of Cibola , Captain García López de Cárdenas , 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

424-441: A Notice of Intent to suspend approvals for new uranium mining in the area. In 2012, Salazar established a 20-year moratorium (known as the "Northern Arizona Withdrawal") withdrawing 1 million acres (4,000 km ) from the permitting process for uranium and hardrock mining, stating "People from all over the country and around the world come to visit the Grand Canyon. Numerous American Indian tribes regard this magnificent icon as

530-439: A band of Native Americans to Christianity. He described the canyon as "profound". James Ohio Pattie, along with a group of American trappers and mountain men, may have been the next European to reach the canyon, in 1826. Jacob Hamblin , a Mormon missionary, was sent by Brigham Young in the 1850s to locate suitable river crossing sites in the canyon. Building good relations with local Hualapai and white settlers, he reached

636-401: A cooler, wetter climate. This increased erosion at higher elevations with the introduction of alpine glaciers while mid-elevations were attacked by frost wedging and lower areas by more vigorous stream scouring. Pluvial lakes also formed during this time. Glaciers and pluvial lakes disappeared and the climate warmed and became drier with the start of Holocene epoch. The Colorado Plateau

742-715: A dense barrier. Groundwater from the C-acquifer can flow laterally, appearing as seeps along the canyon walls at the base of the Coconino Sandstone but can also descend vertically through fault zones to recharge the underlying confined R-aquifer. The R-aquifer, also known as the Red Wall Muav aquifer, is a karst aquifer. It involves an area of substantial fracturing through the Redwall Limestone, Temple Butte Formation and Cambrian Muav Limestone of

848-542: 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, formerly known as the "Crossing of the Fathers", that today lies under Lake Powell . Also in 1776, Fray Francisco Garces, a Franciscan missionary, spent a week near Havasupai unsuccessfully attempting to convert

954-454: A result of uplift bending the rock units. Eroded monoclines leave steeply tilted resistant rock called a hogback and the less steep version is a cuesta. Great tension developed in the crust, probably related to changing plate motions far to the west. As the crust stretched, the Basin and Range Province broke up into a multitude of down-dropped valleys and elongate mountains. Major faults, such as

1060-502: A result the team eventually had to subsist on starvation rations. Passing through (or portaging around) a series of dangerous rapids, the group passed down the Green River , reaching its confluence with the Colorado River, near present-day Moab, Utah , on July 17. Continuing on down the Colorado River, the party encountered more rapids and falls. On August 28, 1869, faced with what some felt to be impassable rapids, three men left

1166-513: A sacred place and millions of people in the Colorado River Basin depend on the river for drinking water, irrigation, industrial and environmental use." However, Salazar's 20-year moratorium on new mines still allows mines with previous authorization to operate. Multiple challenges have been brought into court both against the moratorium and against the operation of uranium mines in the area. The federal government's 2012 moratorium

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1272-659: A seaway along the passive western edge of the continent in the early Paleozoic. At the canyon rim is the Kaibab Formation, limestone deposited in the late Paleozoic (Permian) about 270 million years ago. A 12,000-to-15,000-foot high (3,700 to 4,600 m) extension of the Ancestral Rocky Mountains called the Uncompahgre Mountains were uplifted and the adjacent Paradox Basin subsided. Almost 4 mi. (6.4 km) of sediment from

1378-720: A similar source to the Havasu Spring upwelling from the Redwall-Muav aquifer. Sites with younger estimated mean ages tend to be associated with the unconfined Coconino aquifer. They may recharge quickly as a result of snowmelt, run-off and local precipitation. It is likely that the deeper confined R-aquifer relies primarily on snowmelt from the San Francisco Peaks to recharge. Other research has tried to relate groundwater flow paths to possible levels of risk for contamination and identify vulnerability regions for

1484-515: A substantial departure from prior widely supported scientific consensus. In a 2008 study, Victor Polyak examined caves near the Grand Canyon and placed their origins about 17   million years ago. The study, which was published in the journal Science in 2008, used uranium-lead dating to analyze calcite deposits found on the walls of nine caves throughout the canyon. In another 2008 study, Rebecca Flowers reported on apatite (U-Th)/He thermochronometry results suggesting that parts of

1590-589: A time the only record concerning this rather mythical locality, was rather magnified than detracted from by the accounts of one or two trappers, who professed to have seen the cañon". According to the San Francisco Herald , in a series of articles run in 1853, Captain Joseph R. Walker in January 1851 with his nephew James T. Walker and six men, traveled up the Colorado River to a point where it joined

1696-702: A wide area stretching from the San Francisco Peaks eastwards towards the Four Corners. Archaeological and linguistic evidence suggests the Navajo descended from the Athabaskan people near Great Slave Lake , Canada, who migrated after the 11th   century. In the mythology of some Third Mesa Hopi communities, the Grand Canyon was the location humankind arose out of the Third World from

1802-403: Is Spanish for "red-colored") to mostly clear. The apparent green color is from algae on the riverbed's rocks, not from any significant amount of suspended material. The lack of sediment has also starved sand bars and beaches, but an experimental 12-day-long controlled flood from Glen Canyon Dam in 1996 showed substantial restoration. Similar floods are planned for every 5 to 10 years. One of

1908-775: Is a steep-sided canyon carved by the Colorado River in Arizona , United States. The Grand Canyon is 277 miles (446 km) long, up to 18 miles (29 km) wide and attains a depth of over a mile (6,093 feet or 1,857 meters). The canyon and adjacent rim are contained within Grand Canyon National Park , the Kaibab National Forest , Grand Canyon–Parashant National Monument , the Hualapai Indian Reservation ,

2014-626: Is a volcanic structure with a history similar to that of the San Francisco Peaks: a basalt flow closer to Grants was extruded only about 3000 years ago (see El Malpais National Monument ). These young igneous rocks may record processes in the Earth's mantle that are eating away at deep margins of the relatively stable block of the Plateau. Tectonic activity resumed in Mid Cenozoic time and started to unevenly uplift and slightly tilt

2120-496: Is an asymmetric foreland basin located mostly in southeast Utah and southwest Colorado , but extending into northeast Arizona and northwest New Mexico . The basin is a large elongate northwest to southeast oriented depression formed during the late Paleozoic Era . The basin is bordered on the east by the tectonically uplifted Uncompahgre Plateau , on the northwest by the San Rafael Swell and extends partway into

2226-574: Is called a confined aquifer, while water below the surface and above an aquitard is called an unconfined aquifer. The different geologic levels of the Grand Canyon have created two major aquifers where groundwater collects. The higher C-aquifer is an unconfined aquifer. It collects groundwater that seeps through the Kaibab and Toroweap Formations into the Coconino Sandstone. Below it, the Permian Hermit Formation and Supai Group provide

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2332-420: Is covered with dry grasslands and shrublands, open pinyon-juniper woodland , and mountain woodlands and forests. Electrical power generation is one of the major industries that takes place in the Colorado Plateau region. Most electrical generation comes from coal fired power plants. The rocks of the Colorado Plateau are a source of oil and a major source of natural gas . Major petroleum deposits are present in

2438-558: Is exposed in the various cliffs and canyons (including the Grand Canyon ) that make up the Grand Staircase . Increasingly younger east–west trending escarpments of the Grand Staircase extend north of the Grand Canyon and are named for their color: Within these rocks are abundant mineral resources, including uranium, coal, petroleum, and natural gas. A study of the area's unusually clear geologic history (laid bare due to

2544-495: Is known for its visually overwhelming size and its intricate and colorful landscape. Geologically, it is significant because of the thick sequence of ancient rocks that are well 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 formation later moved these sediments thousands of feet upward and created

2650-679: Is not a natural lake but a reservoir impounded by Glen Canyon Dam . National parks (from south to north to south clockwise): National monuments (alphabetical): Wilderness areas (alphabetical): Other notable protected areas include: Barringer Crater , Dead Horse Point State Park , Glen Canyon National Recreation Area , Goblin Valley State Park , Goosenecks State Park , the Grand Gulch Primitive Area , Kodachrome Basin State Park , Monument Valley , and

2756-1013: The Uinta Mountains and Wasatch Mountains branches of the Rockies in northern and central Utah. It is also bounded by the Rio Grande rift , Mogollon Rim , and the Basin and Range Province (at the Hurricane Fault ). Isolated ranges of the Southern Rocky Mountains , such as the San Juan Mountains in Colorado and the La Sal Mountains in Utah, intermix into the central and southern parts of

2862-629: The Boone and Crockett Club helped form the National Parks Association , which in turn lobbied for the Antiquities Act of 1906 which gave Roosevelt the power to create national monuments. Once the act was passed, Roosevelt immediately added adjacent national forest lands and redesignated the preserve a U.S. National Monument on January 11, 1908. Opponents such as land and mining claim holders blocked efforts to reclassify

2968-472: The Crossing of the Fathers , crossed the location that would become Lees Ferry on a raft in 1858 and Pearce Ferry (later operated by, and named for, Harrison Pearce ). He also acted as an advisor to John Wesley Powell , before his second expedition to the Grand Canyon, serving as a diplomat between Powell and the local native tribes to ensure the safety of his party. In 1857, Edward Fitzgerald Beale

3074-762: The EPA ' s Maximum Contaminant Level for drinking water, 30 μg/L. At 86% of sites, uranium concentrations were below the Canadian level for protection of freshwater aquatic life, 15 μg/L. On August 8, 2023, it was announced that U.S. President Joe Biden will designate Baaj Nwaavjo I’tah Kukveni – Ancestral Footprints of the Grand Canyon National Monument, a move aimed at conserving nearly 1 million acres of greater Grand Canyon landscape. Paradox Basin The Paradox Basin

3180-643: The Havasupai Indian Reservation and the Navajo Nation . The surrounding area is contained within the Baaj Nwaavjo I'tah Kukveni – Ancestral Footprints of the Grand Canyon National Monument . President Theodore Roosevelt was a major proponent of the preservation of the Grand Canyon area and visited it on numerous occasions to hunt and enjoy the scenery. Nearly two billion years of Earth's geological history have been exposed as

3286-456: The Mesozoic era the region was affected by a series of orogenies ( mountain -building events) that deformed western North America and caused a great deal of uplift. Eruptions from volcanic mountain ranges to the west buried vast regions beneath ashy debris. Short-lived rivers, lakes, and inland seas left sedimentary records of their passage. Streams, ponds and lakes produced formations such as

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3392-618: The Pecos Classification , suggests their emergence was around 1200  BCE during the Basketmaker II Era . Beginning with the earliest explorations and excavations, researchers have believed that the Ancestral Puebloans are ancestors of the modern Pueblo peoples . In addition to the Ancestral Puebloans, a number of distinct cultures have inhabited the Grand Canyon area. The Cohonina lived to

3498-726: The San Juan Basin of New Mexico and Colorado, the Uinta Basin of Utah, the Piceance Basin of Colorado, and the Paradox Basin of Utah, Colorado, and Arizona. The Colorado Plateau holds major uranium deposits, and there was a uranium boom in the 1950s. The Atlas Uranium Mill near Moab has left a problematic tailings pile for cleanup. As of 2019, 10 million tons of tailings had been relocated out of an estimated 16 million tons. Major coal deposits are being mined in

3604-532: The San Rafael Swell . Sedona, Arizona and Oak Creek Canyon lie on the south-central border of the Plateau. Many but not all of the Sedona area's cliff formations are protected as wilderness ( Red Rock State Park and Coconino National Forest ). The area has the visual appeal of a national park, but with a small, rapidly growing town in the center. 37°N 110°W  /  37°N 110°W  / 37; -110 Grand Canyon The Grand Canyon

3710-852: The Wasatch Range form the boundaries between the plateaus in the High Plateaus Section. The Uinta Basin, Uncompahgre Uplift, and the Paradox Basin were also formed by movement along structural weaknesses in the region's oldest rock. In Utah, the province includes several higher fault-separated plateaus : Some sources also include the Tushar Mountain Plateau as part of the Colorado Plateau, but others do not. The mostly flat-lying sedimentary rock units that make up these plateaus are found in component plateaus that are between 4,900 to 11,000 feet (1,500 to 3,350 m) above sea level. A supersequence of these rocks

3816-485: 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

3922-578: 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 contains abundant geological evidence of aeolian sand dune deposition. Several parts of the Supai Group also were deposited in non-marine environments. The great depth of

4028-545: The pueblos of the Ancestral Puebloan culture. There are nine U.S. National Parks , a National Historical Park, nineteen U.S. national monuments and dozens of wilderness areas in the province along with millions of acres in U.S. National Forests , many state parks, and other protected lands. In fact, this region has the highest concentration of parklands in North America. Lake Powell , in foreground,

4134-607: The C-aquifer. Much of the water that could potentially recharge the aquifers is likely released as springs rather than reaching the aquifers. Studies of the chemical composition of groundwater at sites across the Grand Canyon region indicate that groundwater contains a fraction of modern water (post-1950), and that many springs have a mix of modern water and older groundwater. Estimated mean ages for South Rim groundwater range from 6 years old (San Francisco Peaks) to nearly 20,000 years old (Bar Four well, Blue Spring). Groundwater age in

4240-742: The Chinle, Moenave, and Kayenta in the Mesozoic era. Later a vast desert formed the Navajo and Temple Cap formations and dry near-shore environment formed the Carmel (see geology of the Zion and Kolob canyons area for details). The area was again covered by a warm shallow sea when the Cretaceous Seaway opened in late Mesozoic time. The Dakota Sandstone and the Tropic Shale were deposited in

4346-539: The Colorado Plateau in Utah, Arizona, Colorado, and New Mexico, though large coal mining projects, such as on the Kaiparowits Plateau , have been proposed and defeated politically. The ITT Power Project, eventually located in Lynndyl, Utah , near Delta, was originally suggested for Salt Wash near Capitol Reef National Park. After a firestorm of opposition, it was moved to a less controversial site. In Utah

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4452-538: The Colorado Plateau into four geologic provinces. These are: The Ancestral Puebloan People lived in the region from roughly 2000 to 700 years ago. A party from Santa Fe led by Fathers Dominguez and Escalante , unsuccessfully seeking an overland route to California, made a five-month out-and-back trip through much of the Plateau in 1776–1777. Despite having lost one arm in the American Civil War , U.S. Army Major and geologist John Wesley Powell explored

4558-466: The Colorado Plateau region and the region to the west some 20 million years ago (as much as 3 kilometers of uplift occurred). Streams had their gradient increased and they responded by downcutting faster. Headward erosion and mass wasting helped to erode cliffs back into their fault-bounded plateaus, widening the basins in-between. Some plateaus have been so severely reduced in size this way that they become mesas or even buttes . Monoclines form as

4664-505: The Colorado Plateau. It is composed of six sections: As the name implies, the High Plateaus Section is, on average, the highest section. North-south trending normal faults that include the Hurricane , Sevier, Grand Wash , and Paunsaugunt separate the section's component plateaus. This fault pattern is caused by the tensional forces pulling apart the adjacent Basin and Range Province to the west, making this section transitional. Occupying

4770-579: 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 Kaibab Plateau that the Grand Canyon bisects is over one thousand feet (300 m) higher at the North Rim than at the South Rim. Almost all runoff from

4876-425: The Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted . While some aspects about the history of incision of the canyon are debated by geologists, several recent studies support the hypothesis that the Colorado River established its course through the area about 5 to 6 million years ago. Since that time, the Colorado River has driven

4982-477: The Colorado River and the Grand Canyon in the first expedition down the canyon. Powell ordered a shipwright to build four reinforced Whitewall rowboats from Chicago and had them shipped west on the newly completed Continental railroad. He hired nine men, including his brother Walter, and collected provisions for ten months. They set out from Green River, Wyoming , on May 24. On June 7, they lost one of their boats, 1/3 of their food, and other badly-needed supplies: as

5088-512: The Colorado all of the way to the Gulf of California . The Grand Canyon became an official national monument in 1908 and a national park in 1919. U.S. President Theodore Roosevelt visited the Grand Canyon in 1903. An avid outdoorsman and staunch conservationist, Roosevelt established the Grand Canyon Game Preserve on November 28, 1906. Livestock grazing was reduced, but predators such as mountain lions, eagles, and wolves were eradicated. Roosevelt along with other members of his conservation group,

5194-406: The Department of Interior started experimenting with “adaptive management” of the Glen Canyon Dam, using a High-Flow Experiment (HFE) water release to shift volumes of sand and monitoring effects such as the dispersal of invasive tamarisk seeds. However, as of 2022, extreme drought has caused water levels in Lake Powell to drop so much that a planned release of water has been delayed, to ensure that

5300-454: The Forest Service had not acted arbitrarily in making its decision. A study examining samples of groundwater from 180 spring sites and 26 wells in the Grand Canyon region has assessed the presence of uranium in groundwater from September 1, 1981, to October 7, 2020. The goal of the study was to establish a baseline assessment of groundwater conditions in the Grand Canyon region. At 95% of sites, maximum observed uranium concentrations were below

5406-448: The Four Corners, Black Mesa in northern Arizona is much closer to the east–west, north–south midpoint of the Plateau Province. Lying southeast of Glen Canyon and southwest of Monument Valley at the north end of the Hopi Reservation, this remote coal-laden highland has about half of the Colorado Plateau's acreage north of it, half south of it, half west of it, and half east of it. The American Association of Petroleum Geologists divides

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5512-423: The Glen Canyon Dam can continue to generate hydropower . Between 2003 and 2011, 2,215 mining claims had been requested that are adjacent to the canyon, including claims for uranium mines. Critics of uranium mining are concerned that uranium will leach into the aquifers feeding the Colorado River and contaminate the water supply for up to 18 million people. In 2009, U.S. Interior Secretary Ken Salazar published

5618-439: The Grand Canyon Trust sought to block the reopening of the Pinyon Plain Mine (formerly Canyon Uranium Mine). Activity at the mine had ceased in 1992, ten years prior to the moratorium on new development in 2012. Appellants challenged the U.S. Forest Service's consultation process for approving reopening of the mine. As of February 22, 2022, the 9th U.S. Circuit Court of Appeals rejected the arguments in No. 20-16401, concluding that

5724-445: The Grand Canyon and especially the height of its strata (most of which formed below sea level) can be attributed to 5,000–10,000 feet (1,500–3,000 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

5830-470: The Grand Canyon and tributary canyons. Springs discharge to the Grand Canyon in areas of lower Paleozoic carbonates, and are associated with geologic faults and fractures. Fractures are believed to provide dominant pathways both for vertical circulation in the Paleozoic section, and for lateral collection and transport of water to springs deep in the canyons. The largest springs discharge from the R-aquifer. A smaller number of springs discharge at lower rates from

5936-425: The Grand Canyon had reached a depth near to the modern depth around 20   million years ago. In a subsequent study published in the journal Science in 2012, she suggested that the western part of the Grand Canyon could be as old as 70   million years. The emerging scientific consensus is that the canyon is made up of multiple segments which formed at different times and eventually connected to become

6042-435: The Hurricane Fault, developed that separate the two regions. The dry climate was in large part a rainshadow effect resulting from the rise of the Sierra Nevada further west. Yet for some reason not fully understood, the neighboring Colorado Plateau was able to preserve its structural integrity and remained a single tectonic block. A second mystery was that while the lower layers of the Plateau appeared to be sinking, overall

6148-425: The Monument Uplift to the west. Its area is roughly 33,000 square miles (85470 km ). The combined sedimentary strata of the Paradox Basin are more than 15,000 feet (4600 m) thick in some places. Unlike most Rocky Mountain basins, the Paradox Basin is an evaporite basin containing sediments from alternating cycles of deep marine and very shallow water. As a result of the thick salt sequences and

6254-416: The NPS, the United States Forest Service , and the Bureau of Land Management are Bears Ears , Rainbow Bridge , Dinosaur , Hovenweep , Wupatki , Sunset Crater Volcano , Grand Staircase–Escalante , El Malpais , Natural Bridges , Canyons of the Ancients , Chaco Culture National Historical Park and the Colorado National Monument . This province is bounded by the Rocky Mountains in Colorado and by

6360-590: The Navajo Volcanic Field, produced about 25 million years ago. The Hopi Buttes in northeastern Arizona are held up by resistant sheets of sodic volcanic rocks, extruded about 7 million years ago. More recent igneous rocks are concentrated nearer the margins of the Colorado Plateau. The San Francisco Peaks near Flagstaff , south of the Grand Canyon , are volcanic landforms produced by igneous activity that began in that area about 6 million years ago and continued until 1064 CE, when basalt erupted in Sunset Crater National Monument . Mount Taylor , near Grants, New Mexico ,

6466-403: 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 those on

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6572-486: The Plateau was rising. The reason for this was discovered upon analyzing data from the USARRAY project. It was found that the asthenosphere had invaded the overlying lithosphere , as a result of an area of mantle upwelling stemming from either the disintegration of the descending Farallon Plate , or the survival of the subducted spreading center connected to the East Pacific Rise and Gorda Ridge beneath western North America, or possibly both. The asthenosphere erodes

6678-553: The South Rim because of the greater elevation (averaging 8,000 feet or 2,400 meters 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 ( State Route 67 ) is limited during the winter season due to road closures. The Grand Canyon is part of the Colorado River basin, which has developed over the past 70   million years. For more than 150 years, scientists have gathered data, proposed new ideas, and debated sometimes contentious theories about

6784-433: The South Rim groundwater system also correlates to longitude, with age increasing from east to west from Red Canyon to Boucher springs. Surprisingly, the Canyon Mine Observation well is more similar to Redwall-Muav aquifer wells (R-aquifer) than to the Coconino C-aquifer. This suggests the possibility of a hydrologic connection or similar recharge sources for that hydrologic position. Old groundwater from Havasupai well may have

6890-404: The Tonto Group. Five individual systems flow through the R-aquifer and compose the regional groundwater-flow system which drains into the Grand Canyon: Kaibab, Uinkaret-Kanab, Marble-Shinumo, Cataract, and Blue Spring. The flow of groundwater in the Grand Canyon region is influenced in multiple ways by geologic faults and folds . Discharge from the R-aquifer appears as springs and seeps in both

6996-429: The United States. They were the first people known to live in the Grand Canyon area. The cultural group has often been referred to in archaeology as the Anasazi, although the term is not preferred by the modern Puebloan peoples . The word "Anasazi" is Navajo for "enemy ancestors" or "alien ancestors". Archaeologists still debate when this distinct culture emerged. The current consensus, based on terminology defined by

7102-439: The Virgin River and continued east into Arizona, traveling along the Grand Canyon and making short exploratory side trips along the way. Walker is reported to have said he wanted to visit the "Moqui" (Hopi) Indians. who he had met briefly before and found exceptionally interesting. In 1858, John Strong Newberry became probably the first geologist to visit the Grand Canyon. In 1869, Major John Wesley Powell set out to explore

7208-450: The additional features typical of the Plateau. The Colorado Plateau has the greatest concentration of U.S. National Park Service (NPS) units in the country outside the Washington, DC metropolitan area. Among its nine national parks are Grand Canyon , Zion , Bryce Canyon , Capitol Reef , Canyonlands , Arches , Black Canyon , Mesa Verde , and Petrified Forest . Among its 18 national monuments and other protected areas managed by

7314-409: The area in 1869 and 1872. Using wooden oak boats and small groups of men, the Powell Geographic Expedition charted this largely unknown region of the United States for the federal government. Construction of the Hoover Dam in the 1930s and the Glen Canyon Dam in the 1960s changed the character of the Colorado River. Dramatically reduced sediment load changed its color from reddish brown ( Colorado

7420-426: The arid and semiarid conditions) has greatly advanced that science. A rain shadow from the Sierra Nevada far to the west and the many ranges of the Basin and Range means that the Colorado Plateau receives six to sixteen inches (15 to 40 cm) of annual precipitation. Higher areas receive more precipitation and are covered in forests of pine, fir, and spruce. Though it can be said that the Plateau roughly centers on

7526-437: The basin include petroleum , uranium , copper , and potash . Much of the petroleum production in the basin has come from porous carbonate deposits, such as algal mounds, of Pennsylvanian age. Additional reservoir types include uplifted fault blocks and discontinuous clastic beds with both stratigraphic and structural traps. The principal productive horizons in the basin include the Mississippian Leadville Limestone ,

7632-409: The down-cutting of the tributaries and retreat of the cliffs, simultaneously deepening and widening the canyon. For thousands of years, the area has been continuously inhabited by Native Americans, who built settlements within the canyon and its many caves. The Pueblo people considered the Grand Canyon a holy site, and made pilgrimages to it. The first European known to have viewed the Grand Canyon

7738-426: The expedition on foot in an attempt to reach a settlement 75 miles (121 km) away. Ironically, the remaining members went safely through the rapids on August 29, 1869, while Seneca Howland, Oramel Howland, and William H. Dunn were murdered. The area through which the three men traveled was marked by tensions between farming and hunting Shivwits and incoming Mormon settlers. Which group was responsible for killing

7844-645: The fact that salt is ductile at relatively low temperatures and pressures, salt tectonics play a major role in the post- Pennsylvanian structural deformation within the basin. Scientists believe the seawater at the base of Paradox Basin may have been trapped there for several hundred million years. However, in 2022 researchers attempting to date the basin unexpectedly discovered relatively "young" water as far down as three kilometers (1.9 miles). "The fresh influx would have been delivered by rainfall, snow melt or natural aquifers as recently as between 400,000 and 1.1 million years ago." Natural resources extracted from

7950-499: The geologic origins of the Grand Canyon and the Colorado River. Formation of the Grand Canyon and the Colorado River may involve a complex history in which multiple factors and geologic processes have interacted over time and in different locations. In the most recent round of "old river" vs. "young river" controversy, researchers have challenged estimates that had placed the age of the canyon at 5–6   million years. The research has aroused considerable controversy because it suggests

8056-468: The interval from 20 to 31 million years: some igneous intrusions in these mountains form laccoliths , a form of intrusion recognized by Grove Karl Gilbert during his studies of the Henry Mountains . Ship Rock (also called Shiprock ), in northwestern New Mexico, and Church Rock and Agathla , near Monument Valley , are erosional remnants of potassium-rich igneous rocks and associated breccias of

8162-738: The largest deposits are in aptly named Carbon County. In Arizona the biggest operation is on Black Mesa , supplying coal to Navajo Power Plant. Perhaps the only one of its kind, a gilsonite plant near Bonanza, southeast of Vernal, Utah , mines this unique, lustrous, brittle form of asphalt, for use in "varnishes, paints,...ink, waterproofing compounds, electrical insulation,...roofing materials." This relatively high, semi-arid to arid province produces many distinctive erosional features such as arches, arroyos , canyons, cliffs, fins, natural bridges , pinnacles, hoodoos , and monoliths that, in various places and extents, have been protected. Also protected are areas of historic or cultural significance, such as

8268-713: The lower end of Black Canyon on March 8, 1858, then continued on by rowboat past the mouth of the Virgin River after the Explorer struck a rock. Ives led his party east into the canyon – they may have been the first Europeans to travel the Diamond Creek drainage. In his "Report Upon the Colorado River of the West" to the Senate in 1861 Ives states that "The marvellous story of Cardinas , that had formed for so long

8374-485: The lower levels of the Plateau. At the same time, as it cools, it expands and lifts the upper layers of the Plateau. Eventually, the great block of Colorado Plateau crust rose a kilometer higher than the Basin and Range. As the land rose, the streams responded by cutting ever deeper stream channels. The most well-known of these streams, the Colorado River , began to carve the Grand Canyon less than 6 million years ago. The Pleistocene epoch brought periodic ice ages and

8480-557: The monument as a U.S. National Park for 11 years. Grand Canyon National Park was finally established as the 17th U.S. National Park by an Act of Congress signed into law by President Woodrow Wilson on February 26, 1919. 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 and management disputes, and forest fire management. The canyon's ecosystem

8586-506: The most geologically intriguing features of the Colorado Plateau is its remarkable stability. Relatively little rock deformation such as faulting and folding has affected this high, thick crustal block within the last 600 million years or so, although there are some newer features such as the Waterpocket Fold of Capitol Reef (estimated 50–70 million years old). In contrast, provinces that have suffered severe deformation surround

8692-460: The mountains and evaporites from the sea were deposited (see geology of the Canyonlands area for detail). Most of the formations were deposited in warm shallow seas and near-shore environments (such as beaches and swamps) as the seashore repeatedly advanced and retreated over the edge of a proto-North America (for detail, see geology of the Grand Canyon area ). The province was probably on

8798-481: The oldest ages recorded by these rocks fall from 1950 to 1680 million years. An erosion surface on the Vishnu Basement Rocks is covered by sedimentary rocks and basalt flows, and these rocks formed in the interval from about 1250 to 750 million years ago: in turn, they were uplifted and split into a range of fault-block mountains . Erosion greatly reduced this mountain range before the encroachment of

8904-465: 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. On December 31, 1857, Ives embarked from the mouth of the Colorado in the stern wheeler steamboat Explorer . His party reached

9010-657: The plateau. Mountain building thrust up the Rocky Mountains to the north and east and tremendous, earth-stretching tension produced the Basin and Range Province to the west and south. Sub ranges of the Southern Rocky Mountains are scattered throughout the Colorado Plateau. The Precambrian and Paleozoic history of the Colorado Plateau is best revealed near its southern end, where the Grand Canyon has exposed rocks with ages that span almost 2 billion years. The oldest rocks at river level are igneous and metamorphic and have been lumped together as Vishnu Basement Rocks ;

9116-462: The region, which acted as a rigid crustal block. The Colorado Plateau Province was uplifted largely as a single block, possibly due to its relative thickness. This relative thickness may be why compressional forces from the orogeny were mostly transmitted through the province instead of deforming it. Pre-existing weaknesses in Precambrian rocks were exploited and reactivated by the compression. It

9222-423: 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 . Between 100,000 and 3   million years ago, volcanic activity deposited ash and lava over the area, which at times completely obstructed the river. These volcanic rocks are

9328-574: The sandstone is predominantly of eolian origin and locally more than 500 meters thick. The Chuska Sandstone caps the Chuska Mountains , and it lies unconformably on Mesozoic rocks deformed during the Laramide orogeny . Younger igneous rocks form spectacular topographic features. The Henry Mountains , La Sal Range , and Abajo Mountains , ranges that dominate many views in southeastern Utah, are formed about igneous rocks that were intruded in

9434-594: The second Director of the US Geological Survey (1881–1894). He was the first to use the term "Grand Canyon", in 1871; previously it had been called the "Big Canyon". In 1889, Frank M. Brown wanted to build a railroad along the Colorado River to carry coal. He, his chief engineer Robert Brewster Stanton , and 14 others started to explore the Grand Canyon in poorly designed cedar wood boats, with no life preservers. Brown drowned in an accident near Marble Canyon : Stanton made new boats and proceeded to explore

9540-462: The shallow marine waters. During times when the seas retreated, stream deposits and dune sands were deposited or older layers were removed by erosion. Over 300 million years passed as layer upon layer of sediment accumulated. It was not until the upheavals that coincided with the formation of the supercontinent Pangea began about 250 million years ago that deposits of marine sediment waned and terrestrial deposits dominate. In late Paleozoic and much of

9646-596: The southeast corner of the Colorado Plateau is the Datil Section. Thick sequences of mid- Tertiary to late- Cenozoic -aged lava covers this section. The development of the province has, in large part, been influenced by structural features in its oldest rocks. Part of the Wasatch Line and its various faults form the province's western edge. Faults that run parallel to the Wasatch Fault that lies along

9752-517: The start of the Cenozoic era and were accompanied by some basaltic lava eruptions and mild deformation. The colorful Claron Formation that forms the delicate hoodoos of Bryce Amphitheater and Cedar Breaks was then laid down as sediments in cool streams and lakes (see geology of the Bryce Canyon area for details). The flat-lying Chuska Sandstone was deposited about 34 million years ago;

9858-549: The three men has been hotly debated. Powell himself visited the area the following year, and was told (through a Mormon interpreter) that the Shivwits had mistakenly killed the men, believing them to be prospectors who had murdered an Indian woman. He chose to smoke a peace pipe with them. Powell went on to become the first Director of the U.S. Bureau of Ethnology of the Smithsonian Institution (1879–1902) and

9964-468: The time of the arrival of Europeans in the 16th   century, newer cultures had evolved. The Hualapai inhabit a 100-mile (160 km) stretch along the pine-clad southern side of the Grand Canyon. The Havasupai have been living in the area near Cataract Canyon since the beginning of the 13th   century, occupying an area the size of Delaware . The Southern Paiutes live in what is now southern Utah and northern Arizona. The Navajo , or Diné, live in

10070-683: The two-billion-year-old Vishnu Schist at the bottom of the Inner Gorge to the 270-million-year-old Kaibab Limestone on the Rim. Within that there is a gap, the Great Unconformity , between 1.75   billion and 1.25   billion years ago for which no deposits are present. Then, between 1.25   billion and 730   million years ago, intermittent sediments began to form the Grand Canyon Supergroup . Many of

10176-478: The underlying aquifers. Almost half of the Kaibab plateau's surface was associated with high to very high vulnerability of the unconfined Coconino aquifer (C-aquifer), while about a fifth of the Kaibab Plateau was estimated to be an area of high vulnerability for the Redwall-Muav aquifer (R-aquifer). The Ancestral Puebloans were a Native American culture centered on the present-day Four Corners area of

10282-423: The warm shallow waters of this advancing and retreating seaway. Several other formations were also produced but were mostly eroded following two major periods of uplift. The Laramide orogeny closed the seaway and uplifted a large belt of crust from Montana to Mexico, with the Colorado Plateau region being the largest block. Thrust faults in Colorado are thought to have formed from a slight clockwise movement of

10388-431: The waterway now traversed by the Colorado River. Of the three central segments, the "Hurricane" was formed 50–70   million years ago, and the "Eastern Grand Canyon" was cut 15–25   million years ago. In contrast, the "Marble Canyon" and "Westernmost Grand Canyon" segments at the ends of the canyon were carved in the last five to six million years. The major geologic exposures in the Grand Canyon range in age from

10494-585: 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, Giralda ". It is speculated that their Hopi guides likely knew routes to the canyon floor, but may have been reluctant to lead the Spanish to the river. No Europeans visited the canyon again for more than two hundred years. Fathers Francisco Atanasio Domínguez and Silvestre Vélez de Escalante were two Spanish priests who, with

10600-612: The west of the Grand Canyon, between 500 and 1200  CE . The Cohonina were ancestors of the Yuman , Havasupai , and Hualapai peoples who inhabit the area today. The Sinagua were a cultural group occupying an area to the southeast of the Grand Canyon, between the Little Colorado River and the Salt River , between approximately 500 and 1425 CE . The Sinagua may have been ancestors of several Hopi clans. By

10706-591: The youngest in the canyon. Groundwater flow in the Grand Canyon region is an active area of study. Groundwater forms when rain soaks down into the earth and reaches the water table . The composition of the earth in a given area determines its permeability , the ease with which water flows through it. Sand is more permeable than clay. Less permeable rock layers composed of clay can block the passage of water and are known as aquitards . More permeable areas of rock that hold and transport groundwater underground are known as aquifers . An area of water bounded by two aquitards

10812-523: Was García López de Cárdenas from Spain, who arrived in 1540. The Grand Canyon is a river valley in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata, and it is also one of the six distinct physiographic sections of the Colorado Plateau province. Even though it is not the deepest canyon in the world ( Kali Gandaki Gorge in Nepal is much deeper ), the Grand Canyon

10918-587: Was along these ancient faults and other deeply buried structures that much of the province's relatively small and gently inclined flexures (such as anticlines , synclines , and monoclines ) formed. Some of the prominent isolated mountain ranges of the Plateau, such as Ute Mountain and the Carrizo Mountains , both near the Four Corners , are cored by igneous rocks that were emplaced about 70 million years ago. Minor uplift events continued through

11024-476: Was permanently changed after the construction of the Glen Canyon Dam in 1963. Average flood levels dropped from 85,000 to 8,000 cubic ft/sec. In the absence of natural flooding, sandbars and beaches eroded and invasive species began to displace native species. Federal officials started releasing floods in the Grand Canyon in hopes of restoring its ecosystem beginning with 1996, 2004, and 2008. In 2018,

11130-482: Was superintendent of an expedition to survey a wagon road along the 35th parallel from Fort Defiance, Arizona to the Colorado River. He led a small party of men in search of water on the Coconino Plateau near the canyon's south rim. On September 19, near present-day National Canyon, they came upon what May Humphreys Stacey described in his journal as "a wonderful canyon; four thousand feet deep. Everybody in

11236-592: Was upheld by the U.S. District Court for Arizona in 2014, but appealed in November 2014 as National Mining Association v. Jewell (No. 14-17350). The 9th Circuit Court of Appeals again upheld the moratorium in 2017, stating that the Secretary of the Interior held valid withdrawal authority. Havasupai Tribe v. Provencio was also argued at multiple court levels based on multiple grounds. The Havasupai people and

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