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Grand Canyon
The Grand Canyon is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is long, up to wide and attains a depth of over a mile (). The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, Grand Canyon–Parashant National Monument, the Hualapai, Hualapai Indian Reservation, the Havasupai Indian Reservation and the Navajo Nation. 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 the Colorado River and its tributaries cut their Stream channel, channels through layer after layer of rock while the Colorado Plateau was Tectonic uplift, uplifted. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado River
The Colorado River () is one of the principal rivers (along with the Rio Grande) in the Southwestern United States and in northern Mexico. The river, the List of longest rivers of the United States (by main stem), 5th longest in the United States, drains an expansive, arid drainage basin, 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 Mexico–United States border, 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. Known for its dramatic canyons, whitewater rapids, and eleven National parks of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arizona
Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the northwest and California to the west, and shares Mexico-United States border, an international border with the Mexican states of Sonora and Baja California to the south and southwest. Its Capital city, capital and List of largest cities, largest city is Phoenix, Arizona, Phoenix, which is the most populous state capital and list of United States cities by population, fifth most populous city in the United States. Arizona is divided into 15 List of counties in Arizona, counties. Arizona is the list of U.S. states and territories by area, 6th-largest state by area and the list of U.S. states and territories by population, 14th-most-populous of the 50 states. It is the 48th state and last of the contiguous United States, contiguous states to be a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science (journal)
''Science'' is the peer review, peer-reviewed academic journal of the American Association for the Advancement of Science (AAAS) and one of the world's top academic journals. It was first published in 1880, is currently circulated weekly and has a subscriber base of around 130,000. Because institutional subscriptions and online access serve a larger audience, its estimated readership is over 400,000 people. ''Science'' is based in Washington, D.C., United States, with a second office in Cambridge, UK. Contents The major focus of the journal is publishing important original scientific research and research reviews, but ''Science'' also publishes science-related news, opinions on science policy and other matters of interest to scientists and others who are concerned with the wide implications of science and technology. Unlike most scientific journals, which focus on a specific field, ''Science'' and its rival ''Nature (journal), Nature'' cover the full range of List of academ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2021 Revised NPS Geologic Stratigraphic Column Of The Grand Canyon
1 (one, unit, unity) is a number, numeral, and glyph. It is the first and smallest positive integer of the infinite sequence of natural numbers. This fundamental property has led to its unique uses in other fields, ranging from science to sports, where it commonly denotes the first, leading, or top thing in a group. 1 is the unit of counting or measurement, a determiner for singular nouns, and a gender-neutral pronoun. Historically, the representation of 1 evolved from ancient Sumerian and Babylonian symbols to the modern Arabic numeral. In mathematics, 1 is the multiplicative identity, meaning that any number multiplied by 1 equals the same number. 1 is by convention not considered a prime number. In digital technology, 1 represents the "on" state in binary code, the foundation of computing. Philosophically, 1 symbolizes the ultimate reality or source of existence in various traditions. In mathematics The number 1 is the first natural number after 0. Each natural number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arizona State Route 67
State Route 67 (SR 67) is a long, north–south state highway in northern Arizona. Also called the Kaibab Plateau – North Rim Parkway, SR 67 is the sole road that links U.S. Route 89A (Arizona), U.S. Route 89A (US 89A) at Jacob Lake, Arizona, Jacob Lake to the North Rim of Grand Canyon National Park. Along the route, the road heads through the national park as well as Kaibab National Forest and traverses extensive coniferous forests. The section inside the national park is maintained by the National Park Service (NPS), whereas the section north of the entrance, completely within Kaibab National Forest, is owned by the Arizona Department of Transportation (ADOT). The road was built in the late 1920s and improved through the 1930s. In 1941, the road received its number, and was given its designation as the parkway in the 1980s. The parkway has received designations as a National Forest Scenic Byway as well as a National Scenic Byway. Route description Signage for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaibab Plateau
The Kaibab Plateau is a plateau almost entirely in Coconino County, Arizona (but extending slightly north into Kane County, Utah) in the Southwestern United States. The high plain is also known as the Buckskin Mountain, Buckskin Plateau, and Kaibab Mountain. Description The plateau, part of the larger Colorado Plateau, is bordered on the south by the Grand Canyon and reaches an elevation of . The plateau is divided between Kaibab National Forest and the "North Rim" portion of Grand Canyon National Park. Tributary canyons of the Colorado River form the plateau's eastern and western boundaries, and tiers of uplifted cliffs define the northern edges of the landform. Winter snowfall is often heavy (sometimes exceeding ), and this creates opportunities for backcountry Nordic skiing and snow camping. This broad feature is heavily forested with aspen, spruce-fir, ponderosa pine, and pinyon-juniper woodland, and stands in sharp contrast to the arid lowlands encircling it. The cool fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kali Gandaki Gorge
The Kali Gandaki Gorge or Andha Galchi is the gorge of the Kali Gandaki (or Gandaki River) in the Himalayas in Nepal. By some sources, it may be one of the deepest gorges in the world. The upper part of the gorge is also called Thak Khola after the local Thakali people who became prosperous from trans-Himalayan trade. Geologically, the gorge is within a structural graben. Background The gorge separates the major peaks of Dhaulagiri () on the west and Annapurna () on the east. The portion of the river directly between Dhaulagiri and Annapurna I ( downstream from Tukuche) is at an elevation of , which is lower than Annapurna I.''Annapurna'' (1:100,000 map), Nepal-Kartenwerk der Arbeitgemeinschaft für vergleichende Hochgebirgsforschung Nr. 9, Nelles Verlag, Munich, 1993. Also seGoogle Earth/ref> As tectonic activity has forced the mountains higher, the river has cut through the uplift. This region is known for shaligram fossils, revered by Hindus as one of five non-living ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratum
In geology and related fields, a stratum (: strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as either '' bedding surfaces'' or ''bedding planes''.Salvador, A. ed., 1994. ''International stratigraphic guide: a guide to stratigraphic classification, terminology, and procedure. 2nd ed.'' Boulder, Colorado, The Geological Society of America, Inc., 215 pp. . Prior to the publication of the International Stratigraphic Guide, older publications have defined a stratum as being either equivalent to a single bed or composed of a number of beds; as a layer greater than 1 cm in thickness and constituting a part of a bed; or a general term that includes both ''bed'' and '' lamina''.Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A. , eds., 2005. ''Glossary of Geology'' 5th ed. Alexandria, Virginia, American Geological Institute. 779 pp. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleozoic
The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma at the start of the Mesozoic Era. The Paleozoic is subdivided into six period (geology), geologic periods (from oldest to youngest), Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. Some geological timescales divide the Paleozoic informally into early and late sub-eras: the Early Paleozoic consisting of the Cambrian, Ordovician and Silurian; the Late Paleozoic consisting of the Devonian, Carboniferous and Permian. The name ''Paleozoic'' was first used by Adam Sedgwick (1785–1873) in 1838 to describe the Cambrian and Ordovician periods. It was redefined by John Phillips (geologist), John Phillips (1800–1874) in 1840 to cover the Cambrian to Permian periods. It is derived from the Ancient Greek, Greek ''palaiós'' (π� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proterozoic
The Proterozoic ( ) is the third of the four geologic eons of Earth's history, spanning the time interval from 2500 to 538.8 Mya, and is the longest eon of Earth's geologic time scale. It is preceded by the Archean and followed by the Phanerozoic, and is the most recent part of the Precambrian "supereon". The Proterozoic is subdivided into three geologic eras (from oldest to youngest): the Paleoproterozoic, Mesoproterozoic and Neoproterozoic. It covers the time from the appearance of free oxygen in Earth's atmosphere to just before the proliferation of complex life on the Earth during the Cambrian Explosion. The name ''Proterozoic'' combines two words of Greek origin: meaning "former, earlier", and , meaning "of life". Well-identified events of this eon were the transition to an oxygenated atmosphere during the Paleoproterozoic; the evolution of eukaryotes via symbiogenesis; several global glaciations, which produced the 300 million years-long Huronian glaciation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
