Marble Canyon | |
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Geography | |
Coordinates | 36°51′49″N111°35′25″W / 36.863622°N 111.590152°W |
Marble Canyon is the section of the Colorado River canyon in northern Arizona from Lee's Ferry to the confluence with the Little Colorado River, which marks the beginning of the Grand Canyon.
Lee's Ferry is a common launching point for river runners starting their journey through Marble Canyon and then onward to the Grand Canyon. Marble Canyon is also well known for the Navajo Bridge, where US Highway 89A crosses the Colorado River.
Marble Canyon marks the western boundary of the Navajo Nation. In 1975, the former Marble Canyon National Monument, which followed the Colorado River northeast from the Grand Canyon to Lee's Ferry, was made part of Grand Canyon National Park.
The name Marble Canyon is a misnomer because there is no marble there. Although John Wesley Powell knew this when he named the canyon, he thought the polished limestone looked like marble. In his words, "The limestone of the canyon is often polished, and makes a beautiful marble. Sometimes the rocks are of many colors – white, gray, pink, and purple, with saffron tints."
Marble Canyon is the site of one of the last great proposed dam projects on the Colorado, the Marble Canyon Dam. Proposed and investigated in the early 1950s by the United States Bureau of Reclamation, [1] the proposal met substantial opposition, notably from the Sierra Club, when a revived proposal was considered by the state of Arizona as part of the Central Arizona Project from 1965 to 1968. The proposed dam was finally abandoned in 1968. Exploratory holes, which were drilled in the Redwall Limestone of the canyon walls in an early phase of the abortive project, can still be seen at Mile 39.2. [2]
The uppermost walls of Marble Canyon are composed of Kaibab Limestone upon the Toroweap Formation upon Coconino Sandstone. [3]
Marble Canyon is the only home of the endangered cactus Pediocactus bradyi . [4]
The Grand Canyon 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.
The Colorado River is one of the principal rivers in the Southwestern United States and in northern Mexico. The 1,450-mile-long (2,330 km) river, the 5th longest in the United States, drains an expansive, arid watershed that encompasses parts of seven U.S. states and two Mexican states. The name Colorado derives from the Spanish language for "colored reddish" due to its heavy silt load. Starting in the central Rocky Mountains of Colorado, it flows generally southwest across the Colorado Plateau and through the Grand Canyon before reaching Lake Mead on the Arizona–Nevada border, where it turns south toward the international border. After entering Mexico, the Colorado approaches the mostly dry Colorado River Delta at the tip of the Gulf of California between Baja California and Sonora.
Glen Canyon Dam is a concrete arch-gravity dam in the southwestern United States, located on the Colorado River in northern Arizona, near the city of Page. The 710-foot-high (220 m) dam was built by the Bureau of Reclamation (USBR) from 1956 to 1966 and forms Lake Powell, one of the largest man-made reservoirs in the U.S. with a capacity of more than 25 million acre-feet (31 km3). The dam is named for Glen Canyon, a series of deep sandstone gorges now flooded by the reservoir; Lake Powell is named for John Wesley Powell, who in 1869 led the first expedition to traverse the Colorado River's Grand Canyon by boat.
The Little Colorado River is a tributary of the Colorado River in the U.S. state of Arizona, providing the principal drainage from the Painted Desert region. Together with its major tributary, the Puerco River, it drains an area of about 26,500 square miles (69,000 km2) in eastern Arizona and western New Mexico. Although it stretches almost 340 miles (550 km), only the headwaters and the lowermost reaches flow year-round. Between St. Johns and Cameron, most of the river is a wide, braided wash, only containing water after heavy snowmelt or flash flooding.
The geology of the Grand Canyon area includes one of the most complete and studied sequences of rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old. Most were deposited in warm, shallow seas and near ancient, long-gone sea shores in western North America. Both marine and terrestrial sediments are represented, including lithified sand dunes from an extinct desert. There are at least 14 known unconformities in the geologic record found in the Grand Canyon.
Lees Ferry is a site on the Colorado River in Coconino County, Arizona in the United States, about 7.5 miles (12.1 km) southwest of Page and 9 miles (14 km) south of the Utah–Arizona state line.
Navajo Bridge is the name of twin steel spandrel arch bridges that cross the Colorado River in the Grand Canyon National Park in northern Coconino County, Arizona, United States. The newer of the two spans carries vehicular traffic on U.S. Route 89A (US 89A) over Marble Canyon between Bitter Springs and Jacob Lake, allowing travel into a remote Arizona Strip region north of the Colorado River including the North Rim of Grand Canyon National Park.
Glen Canyon is a natural canyon carved by a 169.6-mile (272.9 km) length of the Colorado River, mostly in southeastern and south-central Utah, in the United States. Glen Canyon starts where Narrow Canyon ends, at the confluence of the Colorado River and the Dirty Devil River. A small part of the lower end of Glen Canyon extends into northern Arizona and terminates at Lee's Ferry, near the Vermilion Cliffs. Like the Grand Canyon farther downstream, Glen Canyon is part of the immense system of canyons carved by the Colorado River and its tributaries.
Horseshoe Bend is a horseshoe-shaped incised meander of the Colorado River located near the town of Page, Arizona, United States. It is also referred to as the "east rim of the Grand Canyon."
U.S. Route 89 (US 89) is a U.S. Highway in the U.S. state of Arizona that begins in Flagstaff and heads north to the Utah border northwest of Page. US 89 is among the first U.S. Highways established in Arizona between November 11, 1926 and September 9, 1927. Until 1992, US 89 started at the international border in Nogales and was routed through Tucson, Phoenix and Prescott between Nogales and Flagstaff. State Route 79 and State Route 89 are both former sections of US 89.
The Colorado River Storage Project is a United States Bureau of Reclamation project designed to oversee the development of the upper basin of the Colorado River. The project provides hydroelectric power, flood control and water storage for participating states along the upper portion of the Colorado River and its major tributaries.
Marble Canyon is an unincorporated community along the Colorado River in Coconino County, Arizona, United States. It is partially located within the Glen Canyon National Recreation Area and the Grand Canyon National Park.
Bridge Canyon Dam, also called Hualapai Dam, was a proposed dam in the lower Grand Canyon of the Colorado River, in northern Arizona in the United States. It would have been located near Bridge Canyon Rapids in an extremely rugged and isolated portion of the canyon, 235 miles (378 km) downstream of Lees Ferry and at the uppermost end of Lake Mead.
Pediocactus bradyi is a very rare species of cactus known by the common names Brady's pincushion cactus, Brady's hedgehog cactus, and Marble Canyon cactus. It is endemic to Arizona in the US, where it is restricted to Marble Canyon in Coconino County, though its exact distribution is not generally advertised due to poaching concerns. It is limited to a specific type of soil, it has a small distribution, and the species is threatened by a number of human activities. This has been a federally listed endangered species of the United States since 1979.
The Colorado River is a major river of the western United States and northwest Mexico in North America. Its headwaters are in the Rocky Mountains where La Poudre Pass Lake is its source. Located in north central Colorado it flows southwest through the Colorado Plateau country of western Colorado, southeastern Utah and northwestern Arizona where it flows through the Grand Canyon. It turns south near Las Vegas, Nevada, forming the Arizona–Nevada border in Lake Mead and the Arizona–California border a few miles below Davis Dam between Laughlin, Nevada and Needles, California before entering Mexico in the Colorado Desert. Most of its waters are diverted into the Imperial Valley of Southern California. In Mexico its course forms the boundary between Sonora and Baja California before entering the Gulf of California. This article describes most of the major features along the river.
The Middle Permian Toroweap Formation is a thin, darker geologic unit, between the brighter colored units of the Kaibab Limestone above, and Coconino Sandstone below. It is a prominent unit in Grand Canyon, Arizona, USA, found through sections of the South Rim, Grand Canyon, and the North Rim, of the Kaibab Plateau; also the Kaibab's southeast extension to Cape Royal, the Walhalla Plateau. The Colorado River of the Grand Canyon makes its excursion from due-south to due-west around the Walhalla Plateau, as it enters the east end of the Grand Canyon's interior, Granite Gorge. The formation is also found in southeast Utah.
Isis Temple is a prominence in the Grand Canyon, Arizona, Southwestern United States. It is located below the North Rim and adjacent to the Granite Gorge along the Colorado River. The Trinity Creek and canyon flow due south at its west border; its north, and northeast border/flank is formed by Phantom Creek and canyon, a west tributary of Bright Angel Creek; the creeks intersect about 3 mi (4.8 km) southeast, and 1.0 mi (1.6 km) north of Granite Gorge. The Isis Temple prominence, is only about 202 ft (62 m) lower than Grand Canyon Village, the main public center on Grand Canyon’s South Rim.
The Grand Canyon Supergroup is a Mesoproterozoic to a Neoproterozoic sequence of sedimentary strata, partially exposed in the eastern Grand Canyon of Arizona. This group comprises the Unkar Group, Nankoweap Formation, Chuar Group and the Sixtymile Formation, which overlie Vishnu Basement Rocks. Several notable landmarks of the Grand Canyon, such as the Isis Temple and Cheops Pyramid, and the Apollo Temple, are surface manifestations of the Grand Canyon Supergroup.
The Marble Canyon Dam, also known as the Redwall Dam, was a proposed dam on the Colorado River in Arizona. The dam was intended to impound a relatively small reservoir in the central portion of Marble Canyon to develop hydroelectric power. Plans centered on two sites between miles 30 and 40 in the canyon. At one point a 38-mile (61 km) tunnel was proposed to a site just outside Grand Canyon National Park to develop the site's full power generation potential, reducing the Colorado River to a trickle through the park.
Cathedral Rock is a 3,942-foot-elevation (1,202 m) pillar located within Glen Canyon National Recreation Area, in Coconino County of northern Arizona. It is situated less than one mile northwest of Navajo Bridge, and three miles (4.8 km) southwest of Lee's Ferry and the confluence of the Paria and Colorado Rivers, where it towers over 400 feet (120 m) above the surrounding terrain as a landmark of the area. It can be seen from nearby U.S. Route 89A (US 89A) at Marble Canyon. This geographical feature's name was bestowed prior to 1900, and officially adopted in 1969 by the U.S. Board on Geographic Names.