1.
Moenkopi, Arizona
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Moenkopi is a census-designated place in Coconino County, Arizona, United States, adjacent to the southeast side of Tuba City off U. S. Route 160. The population was 964 at the 2010 census, a Hopi community, it was founded in 1870 as a summer farming area by people from the Hopi Third Mesa village of Oraibi, Arizona. It is 40 miles west of Third Mesa and is divided into the villages of Upper Moenkopi and it lies in a 250.306 km2 exclave of the Hopi Reservation which is separated from the main part of the reservation which lies to the east. Both parts are surrounded by Navajo Nation territory, the smaller section comprises only 3.8 percent of the Hopi Reservations land area and 13.2 percent of its population. Located in the center of a valley, Moenkopi is located at 36°6′42″N 111°13′15″W. According to the United States Census Bureau, the CDP has an area of 1.6 square miles. As of the census of 2000, there were 901 people,242 households, the population density is 561.9 people per square mile. There are 284 housing units at a density of 177. 1/sq mi. The racial makeup of the CDP was 96. 67% Native American,1. 66% from two or more races,1. 44% White,0. 22% from other races, and Hispanic or Latino of any race were 0. 78% of the population. 14. 0% of all households were made up of individuals and 5. 8% had someone living alone who was 65 years of age or older, the average household size was 3.72 and the average family size was 4.06. In the CDP, the age distribution of the population shows 35. 2% under the age of 18,9. 4% from 18 to 24,23. 1% from 25 to 44,20. 0% from 45 to 64, the median age was 31 years. For every 100 females there were 96.7 males, for every 100 females age 18 and over, there were 89.0 males. The median income for a household in the CDP was $38,710, males had a median income of $49,063 versus $28,409 for females. The per capita income for the CDP was $11,432, about 15. 6% of families and 13. 8% of the population were below the poverty line, including 15. 8% of those under the age of 18 and 4. 5% of those 65 and older
2.
Geochronology
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Geochronology is the science of determining the age of rocks, fossils, and sediments using signatures inherent in the rocks themselves. Absolute geochronology can be accomplished through radioactive isotopes, whereas relative geochronology is provided by such as palaeomagnetism. By combining multiple geochronological indicators the precision of the age can be improved. Biostratigraphy does not directly provide an absolute age determination of a rock, both disciplines work together hand in hand however, to the point where they share the same system of naming rock layers and the time spans utilized to classify layers within a stratum. By measuring the amount of decay of a radioactive isotope with a known half-life. A number of isotopes are used for this purpose. More slowly decaying isotopes are useful for longer periods of time, two or more radiometric methods can be used in concert to achieve more robust results. Some of the commonly used techniques are, Radiocarbon dating and this technique measures the decay of carbon-14 in organic material and can be best applied to samples younger than about 60,000 years. This technique measures the ratio of two isotopes to the amount of uranium in a mineral or rock. Often applied to the mineral zircon in igneous rocks, this method is one of the two most commonly used for geologic dating. Monazite geochronology is another example of U-Pb dating, employed for dating metamorphism in particular, uranium-lead dating is applied to samples older than about 1 million years. This technique is used to date speleothems, corals, carbonates and its range is from a few years to about 700,000 years. These techniques date metamorphic, igneous and volcanic rocks and they are also used to date volcanic ash layers within or overlying paleoanthropologic sites. The younger limit of the method is a few thousand years. Electron spin resonance dating A series of related techniques for determining the age at which a surface was created. Exposure dating uses the concentration of exotic nuclides produced by cosmic rays interacting with Earth materials as a proxy for the age at which a surface, such as an alluvial fan, was created. Burial dating uses the radioactive decay of 2 cosmogenic elements as a proxy for the age at which a sediment was screened by burial from further cosmic rays exposure. Luminescence dating techniques observe light emitted from such as quartz, diamond, feldspar
3.
Early Triassic
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The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 252.17 Ma and 247.2 Ma, rocks from this epoch are collectively known as the Lower Triassic, which is a unit in chronostratigraphy. The Early Triassic is the oldest epoch of the Mesozoic Era and is divided into the Induan and Olenekian ages, the Lower Triassic series is coeval with the Scythian stage, which is today not included in the official timescales but can be found in older literature. In Europe, most of the Lower Triassic is composed of Buntsandstein, the Permian-Triassic extinction event spawned the Triassic period. The massive extinctions that ended the Permian period and Paleozoic era caused extreme hardships for the surviving species, many types of corals, brachiopods, molluscs, echinoderms, and other invertebrates had completely disappeared. The most common Early Triassic hard-shelled marine invertebrates were bivalves, gastropods, ammonites, echinoids, the most common land vertebrate was the small herbivorous synapsid Lystrosaurus. Early Triassic faunas lacked biodiversity and were relatively homogenous throughout the epoch due to the effects of the extinction, the climate during the Early Triassic epoch was generally arid, rainless and dry and deserts were widespread, however the poles possessed a temperate climate. Until recently the existence of an event about 3 million years following the end-Permian extinctions was not recognised. Large and mobile species disappeared from the tropics, and amongst the species such as molluscs only the ones that could cope with the heat survived. On land the tropics were practically devoid of life, big, active animals only returned to the tropics, and plants recolonised on land when temperatures returned to normal around 247 million years ago. Geologic time scale GeoWhen Database - Early Triassic Palaeos scotese
4.
Zion National Park
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Zion National Park is located in the Southwestern United States, near Springdale, Utah. The lowest elevation is 3,666 ft at Coalpits Wash, located at the junction of the Colorado Plateau, Great Basin, and Mojave Desert regions, the parks unique geography and variety of life zones allow for unusual plant and animal diversity. Numerous plant species as well as 289 species of birds,75 mammals, and 32 reptiles inhabit the parks four life zones, desert, riparian, woodland, and coniferous forest. Zion National Park includes mountains, canyons, buttes, mesas, monoliths, rivers, slot canyons, human habitation of the area started about 8,000 years ago with small family groups of Native Americans, the semi-nomadic Basketmaker Anasazi stem from one of these groups. In turn, the Virgin Anasazi culture developed as the Basketmakers settled in permanent communities, a different group, the Parowan Fremont, lived in the area as well. Both groups moved away by 1300 and were replaced by the Parrusits, Mormons came into the area in 1858 and settled there in the early 1860s. In 1909 the President of the United States, William Howard Taft, named the area a National Monument to protect the canyon, under the name of Mukuntuweap National Monument. In 1918, however, the director of the newly created National Park Service changed the parks name to Zion. According to historian Hal Rothman, The name change played to a prevalent bias of the time, many believed that Spanish and Indian names would deter visitors who, if they could not pronounce the name of a place, might not bother to visit it. The new name, Zion, had greater appeal to an ethnocentric audience, the United States Congress established the monument as a National Park on November 19,1919. The Kolob section was proclaimed a separate Zion National Monument in 1937, the geology of the Zion and Kolob canyons area includes nine formations that together represent 150 million years of mostly Mesozoic-aged sedimentation. At various periods in that warm, shallow seas, streams, ponds and lakes, vast deserts. Uplift associated with the creation of the Colorado Plateaus lifted the region 10,000 feet starting 13 million years ago, the park is located in southwestern Utah in Washington, Iron and Kane counties. Geomorphically, it is located on the Markagunt and Kolob plateaus, the northern part of the park is known as the Kolob Canyons section and is accessible from Interstate 15, exit 40. The 8, 726-foot summit of Horse Ranch Mountain is the highest point in the park, streams in the area take rectangular paths because they follow jointing planes in the rocks. The stream gradient of the Virgin River, whose North Fork flows through Zion Canyon in the park, the road into Zion Canyon is 6 miles long, ending at the Temple of Sinawava. At the Temple the canyon narrows and a foot-trail continues to the mouth of the Zion Narrows, the Zion Canyon road is served by a free shuttle bus from early April to late October and by private vehicles the other months of the year. Other roads in Zion are open to private vehicles year-round, the east side of the park is served by Zion-Mount Carmel Highway, which passes through the Zion–Mount Carmel Tunnel and ends at Mount Carmel
5.
Geological formation
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A formation or geological formation is the fundamental unit of lithostratigraphy. A formation consists of a number of rock strata that have a comparable lithology. Formations are not defined on the thickness of the strata they consist of. The concept of formally defined layers or strata is central to the discipline of stratigraphy. Formations can be divided into members and are themselves frequently parcelled together in groups, the definition and recognition of formations allow geologists to correlate geologic strata across wide distances between outcrops and exposures of rock strata. Formations were initially described to be the essential geologic time markers based on relative ages, the divisions of the geological time scale were the formations described and put in chronological order by the geologists and stratigraphers of the 18th and 19th centuries. Geologic formations are sedimentary rock layers, but may also be metamorphic rocks. Igneous intrusive rocks are not divided into formations. Formations are the only formal lithostratigraphic units into which the stratigraphic column everywhere should be divided completely on the basis of lithology, Formations must be able to be delineated at the scale of geologic mapping practiced in the region. The thickness of formations may range from less than a meter to several thousand meters, geologic formations are typically named for the geographic area in which they were first described. Strictly, formations cannot be defined on any other criteria except primary lithology, sequence stratigraphy is a concept which challenges the idea of strict lithostratigraphic units by defining units based on events in sedimentary basins such as oceanic regressions and transgressions. The term formation is used informally to refer to a specific grouping of rocks. Formation is also used informally to describe the sometimes odd shapes that rocks acquire through erosional or depositional processes, such a formation is said to be abandoned when it is no longer affected by the geologic agent that produced it. Some well known cave formations include stalactites and stalagmites, geochronology List of Rock Formations List of Chinese geological formations List of fossil sites
6.
Kaibab Limestone
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The Kaibab Limestone is a resistant cliff-forming, Permian geologic formation that crops out across the U. S. states of northern Arizona, southern Utah, east central Nevada and southeast California. It is also known as the Kaibab Formation in Arizona, Nevada, the Kaibab Limestone forms the rim of the Grand Canyon. In the Big Maria Mountains, California, the Kaibab Limestone is highly metamorphosed, the Kaibab Limestone was named by Darton in 1910 for the Kaibab Plateau, which is on the north side of Grand Canyon in Coconino County, Arizona. In his definition of the Kaibab Limestone formation, no type locality was designated and he also designated the Kaibab Limestone as the upper formation of the Aubrey Group, a now-abandoned stratigraphic unit. In 1921, Bassler and Reeside revised Dartons work and defined the Harrisburg Member of the Kaibab Limestone and he also revised Kaibab Limestones lower contact and divided it into informal alpha, beta and gamma members. Later in the 1970s, its contact was revised and its aerial extent were defined. Also, unsuccessful attempts were made to raise the formation to group rank, in 1982, Warren Hamilton renamed it as the Kaibab Marble and determined its areal extent for California. In 1991, Sorauf and Billingsley subdivided the Kaibab Limestone into Fossil Mountain Member and they designated the strata comprising McKees alpha member as the Harrisburg Member and the strata comprising McKees beta member as the Fossil Mountain Member. The Fossil Mountain Member was named for Fossil Mountain along the south rim near the Bass Trail, McKees gamma member is considered to be part of the Fossil Mountain Member. Later research has further redefined the extent of the Kaibab Limestone. The Kaibab Limestone is an assemblage of sedimentary rock types. It consists of a complexity of interfingering and interbedded carbonate and siliciclastic sedimentary rocks, in addition, intense post-depositional changes have created more composition variation by the alteration of limestone to dolostone and the silicification of limestone to form chert. In the western Grand Canyon region, the Fossil Mountain Member consists of fossiliferous and cherty limestone with an abundant, within the Grand Canyon region, the Kaibab Limestone overlies gypsum and contorted sandstones of the Toroweap Formation. Originally, geologists interpreted the lower contact of the Kaibab Limestone to be an unconformity based on the presence of local intraformational breccias, as a result, this contact is inferred to be conformable or only locally a disconformity. South and east of the Grand Canyon, the evaporites and contorted sandstones of Toroweap Formation interfinger with and are replaced by cross-bedded sandstones of the Coconino Sandstone, as a result, the Kaibab Limestone directly overlies the Coconino Sandstone in the Mogollon Rim region. The Kaibab Limestone directly overlies the White Rim Sandstone in northeastern Arizona, the upper contact of the Kaibab Limestone with the overlying Moenkopi Formation is an erosional unconformity and disconformity. These paleovalleys are often filled with conglomerates and breccias that are known as the Rock Canyon conglomerate, within the Marble Canyon and eastern Grand Canyon regions and south into Verde Valley, upper contact of the Kaibab Limestone with the Moenkopi Formation is an erosional disconformity. The unconformity and disconformity are inferred to represent most of Permian time, as a result, the Kaibab Limestone forms the surface of many of the vast plateaus that border the Grand Canyon
7.
Sandstone
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Sandstone is a clastic sedimentary rock composed mainly of sand-sized minerals or rock grains. Most sandstone is composed of quartz or feldspar because these are the most common minerals in the Earths crust, like sand, sandstone may be any color, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, quartz-bearing sandstone is converted into quartzite through heating and pressure, usually related to tectonic compression within orogenic belts. They are formed from cemented grains that may either be fragments of a rock or be mono-minerallic crystals. The cements binding these grains together are typically calcite, clays, grain sizes in sands are defined within the range of 0.0625 mm to 2 mm. The formation of sandstone involves two principal stages, first, a layer or layers of sand accumulates as the result of sedimentation, either from water or from air. Typically, sedimentation occurs by the settling out from suspension. The most common cementing materials are silica and calcium carbonate, which are derived either from dissolution or from alteration of the sand after it was buried. Colours will usually be tan or yellow, a predominant additional colourant in the southwestern United States is iron oxide, which imparts reddish tints ranging from pink to dark red, with additional manganese imparting a purplish hue. Red sandstones are seen in the Southwest and West of Britain, as well as central Europe. The regularity of the latter favours use as a source for masonry, either as a building material or as a facing stone. These physical properties allow the grains to survive multiple recycling events. Quartz grains evolve from rock, which are felsic in origin. Feldspathic framework grains are commonly the second most abundant mineral in sandstones, Feldspar can be divided into two smaller subdivisions, alkali feldspars and plagioclase feldspars. The different types of feldspar can be distinguished under a petrographic microscope, below is a description of the different types of feldspar. Alkali feldspar is a group of minerals in which the composition of the mineral can range from KAlSi3O8 to NaAlSi3O8. Plagioclase feldspar is a group of solid solution minerals that range in composition from NaAlSi3O8 to CaAl2Si2O8. Lithic framework grains are pieces of ancient source rock that have yet to weather away to individual mineral grains, accessory minerals are all other mineral grains in a sandstone, commonly these minerals make up just a small percentage of the grains in a sandstone
8.
Arizona
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Arizona is a state in the southwestern region of the United States. It is also part of the Western United States and the Mountain West states and it is the sixth largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix, Arizona is one of the Four Corners states. It has borders with New Mexico, Utah, Nevada, California, and Mexico, Arizonas border with Mexico is 389 miles long, on the northern border of the Mexican states of Sonora and Baja California. Arizona is the 48th state and last of the states to be admitted to the Union. Historically part of the territory of Alta California in New Spain, after being defeated in the Mexican–American War, Mexico ceded much of this territory to the United States in 1848. The southernmost portion of the state was acquired in 1853 through the Gadsden Purchase, Southern Arizona is known for its desert climate, with very hot summers and mild winters. There are ski resorts in the areas of Flagstaff, Alpine, in addition to the Grand Canyon National Park, there are several national forests, national parks, and national monuments. To the European settlers, their pronunciation sounded like Arissona, the area is still known as alĭ ṣonak in the Oodham language. Another possible origin is the Basque phrase haritz ona, as there were numerous Basque sheepherders in the area, There is a misconception that the states name originated from the Spanish term Árida Zona. See also lists of counties, islands, rivers, lakes, state parks, national parks, Arizona is in the Southwestern United States as one of the Four Corners states. Arizona is the sixth largest state by area, ranked after New Mexico, of the states 113,998 square miles, approximately 15% is privately owned. The remaining area is public forest and park land, state trust land, Arizona is well known for its desert Basin and Range region in the states southern portions, which is rich in a landscape of xerophyte plants such as the cactus. This regions topography was shaped by volcanism, followed by the cooling-off. Its climate has hot summers and mild winters. The state is well known for its pine-covered north-central portion of the high country of the Colorado Plateau. Like other states of the Southwest United States, Arizona has an abundance of mountains, despite the states aridity, 27% of Arizona is forest, a percentage comparable to modern-day France or Germany. The worlds largest stand of pine trees is in Arizona
9.
Nevada
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Nevada is a state in the Western, Mountain West, and Southwestern regions of the United States of America. Nevada is the 7th most extensive, the 34th most populous, nearly three-quarters of Nevadas people live in Clark County, which contains the Las Vegas–Paradise metropolitan area where three of the states four largest incorporated cities are located. Nevada is officially known as the Silver State because of the importance of silver to its history and economy. It is also known as the Battle Born State, because it achieved statehood during the Civil War, as the Sage-brush State, for the plant of the same name. Nevada borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, Nevada is largely desert and semi-arid, much of it located within the Great Basin. Areas south of the Great Basin are located within the Mojave Desert, while Lake Tahoe, about 86% of the states land is managed by various jurisdictions of the U. S. federal government, both civilian and military. Before European contact, Native Americans of the Paiute, Shoshone, the first Europeans to explore the region were Spanish. They called the region Nevada because of the snow covered the mountains in winter. The area formed part of the Viceroyalty of New Spain, the United States annexed the area in 1848 after its victory in the Mexican–American War, and it was incorporated as part of Utah Territory in 1850. The discovery of silver at the Comstock Lode in 1859 led to a boom that became an impetus to the creation of Nevada Territory out of western Utah Territory in 1861. Nevada became the 36th state on October 31,1864, as the second of two added to the Union during the Civil War. Nevada has a reputation for its libertarian laws, in 1940, with a population of just over 110,000 people, Nevada was by far the least-populated state, with less than half the population of the next least-populated state. However, legalized gambling and lenient marriage and divorce laws transformed Nevada into a major tourist destination in the 20th century, Nevada is the only U. S. state where prostitution is legal, though it is illegal in Clark County, Washoe County and Carson City. The tourism industry remains Nevadas largest employer, with mining continuing as a sector of the economy. The name Nevada comes from the Spanish nevada, meaning snow-covered, most Nevadans pronounce the second syllable of their state name using the vowel of trap. Many from outside the Western United States pronounce it with the vowel of father, although the latter pronunciation is closer to the Spanish pronunciation, it is not the pronunciation preferred by most Nevadans. State Assemblyman Harry Mortenson proposed a bill to recognize the alternate pronunciation of Nevada, though the bill was not supported by most legislators, the Nevadan pronunciation is the de facto official one, since it is the one used by the state legislature. Nevada is almost entirely within the Basin and Range Province, and is broken up by many mountain ranges
10.
Utah
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Utah is a state in the western United States. It became the 45th state admitted to the U. S. on January 4,1896, Utah is the 13th-largest by area, 31st-most-populous, and 10th-least-densely populated of the 50 United States. Utah has a population of more than 3 million, approximately 80% of whom live along the Wasatch Front, Utah is bordered by Colorado to the east, Wyoming to the northeast, Idaho to the north, Arizona to the south, and Nevada to the west. It also touches a corner of New Mexico in the southeast, approximately 62% of Utahns are reported to be members of The Church of Jesus Christ of Latter-day Saints or LDS, which greatly influences Utahn culture and daily life. The LDS Churchs world headquarters is located in Salt Lake City, Utah is the only state with a majority population belonging to a single church. The state is a center of transportation, education, information technology and research, government services, mining, in 2013, the U. S. Census Bureau estimated that Utah had the second fastest-growing population of any state. St. George was the metropolitan area in the United States from 2000 to 2005. Utah also has the 14th highest median income and the least income inequality of any U. S. state. A2012 Gallup national survey found Utah overall to be the best state to live in based on 13 forward-looking measurements including various economic, lifestyle, the name Utah is derived from the name of the Ute tribe. It means people of the mountains in the Ute language, according to other sources Utah is derived from the Apache name Yudah which means Tall. These Native American tribes are subgroups of the Ute-Aztec Native American ethnicity and were sedentary, the Ancestral Pueblo people built their homes through excavations in mountains, and the Fremont people built houses of straw before disappearing from the region around the 15th century. Another group of Native Americans, the Navajo, settled in the region around the 18th century, in the mid-18th century, other Uto-Aztecan tribes, including the Goshute, the Paiute, the Shoshone, and the Ute people, also settled in the region. These five groups were present when the first European explorers arrived, the southern Utah region was explored by the Spanish in 1540, led by Francisco Vásquez de Coronado, while looking for the legendary Cíbola. A group led by two Catholic priests—sometimes called the Dominguez-Escalante Expedition—left Santa Fe in 1776, hoping to find a route to the coast of California, the expedition traveled as far north as Utah Lake and encountered the native residents. The Spanish made further explorations in the region, but were not interested in colonizing the area because of its desert nature, in 1821, the year Mexico achieved its independence from Spain, the region became known as part of its territory of Alta California. European trappers and fur traders explored some areas of Utah in the early 19th century from Canada, the city of Provo, Utah was named for one, Étienne Provost, who visited the area in 1825. The city of Ogden, Utah was named after Peter Skene Ogden, in late 1824, Jim Bridger became the first known English-speaking person to sight the Great Salt Lake. Due to the salinity of its waters, Bridger thought he had found the Pacific Ocean
11.
New Mexico
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New Mexico is a state located in the southwestern region of the United States of America. It was admitted to the Union as the 47th state on January 6,1912 and it is usually considered one of the Mountain States. New Mexico is fifth by area, the 36th-most populous, inhabited by Native Americans for thousands of years before European exploration, New Mexico was colonized by the Spanish in 1598 Imperial Spanish viceroyalty of New Spain. Later, it was part of independent Mexico before becoming a U. S. territory and eventually a U. S. state as a result of the Mexican–American War. Among U. S. states, New Mexico has the highest percentage of Hispanics, the major Native American nations in the state are Navajo, Pueblo, and Apache peoples. The demography and culture of the state are shaped by these strong Hispanic and Native American influences and its scarlet and gold colors are taken from the royal standards of Spain, along with the ancient sun symbol of the Zia, a Pueblo-related tribe. New Mexico, or Nuevo México in Spanish, is incorrectly believed to have taken its name from the nation of Mexico. The name simply stuck, even though the area had no connection to Mexico or the Mexica Indian tribes, Mexico, formerly a part of New Spain, adopted its name centuries later in 1821, after winning independence from Spanish rule. New Mexico was a part of the independent Mexican Empire and Federal Republic of Mexico for 27 years,1821 through 1848, New Mexico and Mexico developed as neighboring Spanish-speaking communities under Spanish rule, with relatively independent histories. The states total area is 121,412 square miles, the eastern border of New Mexico lies along 103° W longitude with the state of Oklahoma, and 2.2 miles west of 103° W longitude with Texas. On the southern border, Texas makes up the eastern two-thirds, while the Mexican states of Chihuahua and Sonora make up the western third, the western border with Arizona runs along the 109°03 W longitude. The southwestern corner of the state is known as the Bootheel, the 37° N latitude parallel forms the northern boundary with Colorado. The states New Mexico, Colorado, Arizona, and Utah come together at the Four Corners in the corner of New Mexico. New Mexico, although a state, has very little water. Its surface water area is about 250 square miles, the New Mexican landscape ranges from wide, rose-colored deserts to broken mesas to high, snow-capped peaks. Despite New Mexicos arid image, heavily forested mountain wildernesses cover a significant portion of the state, the Sangre de Cristo Mountains, the southernmost part of the Rocky Mountains, run roughly north-south along the east side of the Rio Grande in the rugged, pastoral north. The most important of New Mexicos rivers are the Rio Grande, Pecos, Canadian, San Juan, the Rio Grande is tied for the fourth-longest river in the United States. Tourists visiting these sites bring significant money to the state, other areas of geographical and scenic interest include Kasha-Katuwe Tent Rocks National Monument and the Gila Wilderness in the southwest of the state
12.
Colorado
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Colorado is a state in the United States encompassing most of the Southern Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains. Colorado is part of the Western United States, the Southwestern United States, Colorado is the 8th most extensive and the 21st most populous of the 50 United States. The United States Census Bureau estimates that the population of Colorado was 5,540,545 on July 1,2016, the state was named for the Colorado River, which Spanish travelers named the Río Colorado for the ruddy silt the river carried from the mountains. The Territory of Colorado was organized on February 28,1861, Colorado is nicknamed the Centennial State because it became a state in the same year as the centennial of the United States Declaration of Independence. Colorado is noted for its landscape of mountains, forests, high plains, mesas, canyons, plateaus, rivers. Denver is the capital and the most populous city of Colorado, residents of the state are properly known as Coloradans, although the term Coloradoan has been used archaically and lives on in the title of Fort Collins newspaper, the Coloradoan. Colorado, Wyoming and Utah are the states which have boundaries defined solely by lines of latitude and longitude. The summit of Mount Elbert at 14,440 feet elevation in Lake County is the highest point in Colorado, Colorado is the only U. S. state that lies entirely above 1,000 meters elevation. The point where the Arikaree River flows out of Yuma County, Colorado and this point, which holds the distinction of being the highest low elevation point of any state, is higher than the high elevation points of 18 states and the District of Columbia. A little less than one half of the area of Colorado is flat, East of the Rocky Mountains are the Colorado Eastern Plains of the High Plains, the section of the Great Plains within Nebraska at elevations ranging from roughly 3,350 to 7,500 feet. The Colorado plains were mostly prairies, but they have many patches of forests, buttes. Eastern Colorado is presently covered in farmland and rangeland, along with small farming villages. Precipitation is fair, averaging from 15 to 25 inches annually, corn, wheat, hay, soybeans, and oats are all typical crops, and most of the villages and towns in this region boast both a water tower and a grain elevator. Irrigation water is available from the South Platte, the Arkansas River, and a few other streams, however, heavy use of ground water from wells for irrigation has caused underground water reserves to decline. As well as agriculture, eastern Colorado hosts considerable livestock, such as cattle ranches. Roughly 70% of Colorados population resides along the edge of the Rocky Mountains in the Front Range Urban Corridor between Cheyenne, Wyoming, and Pueblo, Colorado. This region is protected from prevailing storms that blow in from the Pacific Ocean region by the high Rockies in the middle of Colorado. The Front Range includes Denver, Boulder, Fort Collins, Loveland, Colorado Springs, Pueblo, Greeley and other townships, on the other side of the Rockies, the significant population centers in Western Colorado are the cities of Grand Junction, Durango, and Montrose
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Southwestern United States
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The population of the area is around 11 million people, with over half that in Arizona, the most populous cities are Phoenix, El Paso, Las Vegas, Albuquerque, and Tucson. Most of the area was part of the Viceroyalty of New Spain in the Spanish Empire before becoming part of Mexico and it became part of the United States through the Treaty of Guadalupe Hidalgo and the Gadsden Purchase. The deserts dominate the southern and western reaches of the area, the two major rivers of the region are the Colorado River, running in the northern and western areas, and the Rio Grande, running in the south. Formed approximately 8000 years ago, the Chihuahuan Desert is a dry desert. The Chihuahuan Desert spreads across the portion of the region, covering from southeastern Arizona, across southern New Mexico. While it is the second largest desert in the United States, only a third of the desert is within the United States, El Paso is the major city in this desert, with other smaller cities being Las Cruces and Roswell in New Mexico. The Chihuahuan is a rain shadow desert, formed two mountain ranges which block oceanic precipitation from reaching the area. The most prolific plants in this region are agave, yucca and creosote bushes, when people think of the desert southwest, the landscape of the Sonoran Desert is what mostly comes to mind. Rainfall averages between 4–12 inches per year, and the deserts most widely known inhabitant is the saguaro cactus and it is bounded on the northwest by the Mojave Desert, to the north by the Colorado Plateau and to the east by the Arizona Mountains forests and the Chihuahuan Desert. The portion of the Sonora Desert which lies in the Southwestern United States is the most populated area within the region. Six of the top ten major population centers of the region are found within its borders, Phoenix, Tucson, Mesa, Chandler, Glendale, also within its borders are Yuma and Prescott Arizona. The most northwest portion of the American Southwest is covered by the Mojave Desert, bordered on the south by the Sonoran Desert and the east by the Colorado Plateau, its range within the region makes up the southeast tip of Nevada, and the northwestern corner of Arizona. In terms of topography, the Mojave is very similar to the Great Basin Desert, the Mojave is the smallest, driest and hottest desert within the United States. The Mojave gets less than six inches of rain annually, the most prolific vegetation is the tall Joshua tree, which grow as tall as 40 feet, and are thought to live almost 1000 years. Other major vegetation includes the Parry saltbush and the Mojave sage, the Colorado Plateau varies from the large stands of forests in the west, including the largest stand of ponderosa pine trees in the world, to the Mesas to the east. Although not called a desert, the Colorado Plateau is mostly made up of high desert, the Plateau is characterized by a series of plateaus and mesas, interspersed with canyons. The most dramatic example is the Grand Canyon, but that is one of many dramatic vistas included within the Plateau, which includes spectacular lava formations, painted deserts, sand dunes, and badlands. One of the most distinctive features of the Plateau is its longevity, the Plateau can be divided into six sections, three of which fall into the Southwest region
14.
United States
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Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east, the state of Hawaii is an archipelago in the mid-Pacific Ocean. The U. S. territories are scattered about the Pacific Ocean, the geography, climate and wildlife of the country are extremely diverse. At 3.8 million square miles and with over 324 million people, the United States is the worlds third- or fourth-largest country by area, third-largest by land area. It is one of the worlds most ethnically diverse and multicultural nations, paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century, the United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the following the Seven Years War led to the American Revolution. On July 4,1776, during the course of the American Revolutionary War, the war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power. The current constitution was adopted in 1788, after the Articles of Confederation, the first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties. During the second half of the 19th century, the American Civil War led to the end of slavery in the country. By the end of century, the United States extended into the Pacific Ocean. The Spanish–American War and World War I confirmed the status as a global military power. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the sole superpower. The U. S. is a member of the United Nations, World Bank, International Monetary Fund, Organization of American States. The United States is a developed country, with the worlds largest economy by nominal GDP. It ranks highly in several measures of performance, including average wage, human development, per capita GDP. While the U. S. economy is considered post-industrial, characterized by the dominance of services and knowledge economy, the United States is a prominent political and cultural force internationally, and a leader in scientific research and technological innovations. In 1507, the German cartographer Martin Waldseemüller produced a map on which he named the lands of the Western Hemisphere America after the Italian explorer and cartographer Amerigo Vespucci
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U.S. state
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A U. S. state is a constituent political entity of the United States of America. There are 50 states, which are together in a union with each other. Each state holds administrative jurisdiction over a geographic territory. Due to the shared sovereignty between each state and the government, Americans are citizens of both the federal republic and of the state in which they reside. State citizenship and residency are flexible, and no government approval is required to move between states, except for persons covered by certain types of court orders. States range in population from just under 600,000 to over 39 million, four states use the term commonwealth rather than state in their full official names. States are divided into counties or county-equivalents, which may be assigned some local authority but are not sovereign. County or county-equivalent structure varies widely by state, State governments are allocated power by the people through their individual constitutions. All are grounded in principles, and each provides for a government. States possess a number of powers and rights under the United States Constitution, Constitution has been amended, and the interpretation and application of its provisions have changed. The general tendency has been toward centralization and incorporation, with the government playing a much larger role than it once did. There is a debate over states rights, which concerns the extent and nature of the states powers and sovereignty in relation to the federal government. States and their residents are represented in the federal Congress, a legislature consisting of the Senate. Each state is represented in the Senate by two senators, and is guaranteed at least one Representative in the House, members of the House are elected from single-member districts. Representatives are distributed among the states in proportion to the most recent constitutionally mandated decennial census, the Constitution grants to Congress the authority to admit new states into the Union. Since the establishment of the United States in 1776, the number of states has expanded from the original 13 to 50, alaska and Hawaii are the most recent states admitted, both in 1959. The Constitution is silent on the question of states have the power to secede from the Union. Shortly after the Civil War, the U. S. Supreme Court, in Texas v. White, as a result, while the governments of the various states share many similar features, they often vary greatly with regard to form and substance
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California
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California is the most populous state in the United States and the third most extensive by area. Located on the western coast of the U. S, California is bordered by the other U. S. states of Oregon, Nevada, and Arizona and shares an international border with the Mexican state of Baja California. Los Angeles is Californias most populous city, and the second largest after New York City. The Los Angeles Area and the San Francisco Bay Area are the nations second- and fifth-most populous urban regions, California also has the nations most populous county, Los Angeles County, and its largest county by area, San Bernardino County. The Central Valley, an agricultural area, dominates the states center. What is now California was first settled by various Native American tribes before being explored by a number of European expeditions during the 16th and 17th centuries, the Spanish Empire then claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its war for independence. The western portion of Alta California then was organized as the State of California, the California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom. If it were a country, California would be the 6th largest economy in the world, fifty-eight percent of the states economy is centered on finance, government, real estate services, technology, and professional, scientific and technical business services. Although it accounts for only 1.5 percent of the states economy, the story of Calafia is recorded in a 1510 work The Adventures of Esplandián, written as a sequel to Amadis de Gaula by Spanish adventure writer Garci Rodríguez de Montalvo. The kingdom of Queen Calafia, according to Montalvo, was said to be a land inhabited by griffins and other strange beasts. This conventional wisdom that California was an island, with maps drawn to reflect this belief, shortened forms of the states name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, various estimates of the native population range from 100,000 to 300,000. The Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups also were diverse in their organization with bands, tribes, villages. Trade, intermarriage and military alliances fostered many social and economic relationships among the diverse groups, the first European effort to explore the coast as far north as the Russian River was a Spanish sailing expedition, led by Portuguese captain Juan Rodríguez Cabrillo, in 1542. Some 37 years later English explorer Francis Drake also explored and claimed a portion of the California coast in 1579. Spanish traders made unintended visits with the Manila galleons on their trips from the Philippines beginning in 1565
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Stratigraphic unit
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Units must be mappable and distinct from one another, but the contact need not be particularly distinct. For instance, a unit may be defined by such as when the sandstone component exceeds 75%. Sequences of sedimentary and volcanic rocks are subdivided on the basis of their lithology, going from smaller to larger in scale, the main units recognised are Bed, Member, Formation, Group and Supergroup. A bed is a distinct layer within a member or formation and is the smallest recognisable stratigraphic unit. These are not normally named, but may be in the case of a marker horizon, a member is a named lithologically distinct part of a formation. Not all formations are subdivided in this way and even where they are recognized, formations are the primary units used in the subdivision of a sequence and may vary in scale from tens of centimetres to kilometres. They should be distinct lithologically from other formations, although the boundaries do not need to be sharp, to be formally recognised, a formation must have sufficient extent to be useful in mapping an area. A group is a set of two or more formations that share certain lithological characteristics, a group may be made up of different formations in different geographical areas and individual formations may appear in more than one group. A supergroup is a set of two or more associated groups and/or formations that share certain lithological characteristics, a supergroup may be made up of different groups in different geographical areas. A sequence of fossil-bearing sedimentary rocks can be subdivided on the basis of the occurrence of fossil taxa. A unit defined in this way is known as a biostratigraphic unit, the five commonly used types of biozone are assemblage, range, abundance, interval and lineage zones. An assemblage zone is a stratigraphic interval characterised by an assemblage of three or more coexisting fossil taxa that distinguish it from surrounding strata. A range zone is an interval that represents the occurrence range of a specific fossil taxon. An abundance zone is an interval in which the abundance of a particular taxon is significantly greater than seen in neighbouring parts of the succession. An interval zone is a stratigraphic interval whose top and base are defined by horizons that mark the first or last occurrence of two different taxa, a lineage zone is a stratigraphic interval that contains fossils that represent parts of the evolutionary lineage of a particular fossil group. This is a case of a range zone. Chronostratigraphy Glaciology Magnetostratigraphy Sedimentology Sequence stratigraphy Stratigraphy International Commission on Stratigraphy Stratigraphic Guide
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Colorado Plateau
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The province covers an area of 337,000 km2 within western Colorado, northwestern New Mexico, southern and eastern Utah, and northern Arizona. About 90% of the area is drained by the Colorado River and its tributaries, the Green, San Juan. Most of the remainder of the plateau is drained by the Rio Grande, the Colorado Plateau is largely made up of high desert, with scattered areas of forests. In the southwest corner of the Colorado Plateau lies the Grand Canyon of the Colorado River, much of the Plateaus landscape is related, in both appearance and geologic history, to the Grand Canyon. The nickname Red Rock Country suggests the brightly colored rock left bare to the view by dryness, domes, hoodoos, fins, reefs, river narrows, natural bridges, and slot canyons are only some of the additional features typical of the Plateau. The Colorado Plateau has the greatest concentration of U. S. National Park Service units in the country outside of the Washington, DC metropolitan area. Among its ten National Parks are Grand Canyon, Glen Canyon, Zion, Bryce Canyon, Capitol Reef, Canyonlands, Arches, Mesa Verde, and Petrified Forest. The province is bounded by the Rocky Mountains in Colorado, and by the Uinta Mountains and Wasatch Mountains branches of the Rockies in northern and it is also bounded by the Rio Grande Rift, Mogollon Rim and the Basin and Range Province. Isolated ranges of the Southern Rocky Mountains such as the San Juan Mountains in Colorado, north-south trending normal faults that include the Hurricane, Sevier, Grand Wash, and Paunsaugunt separate the sections component plateaus. This fault pattern is caused by the forces pulling apart the adjacent Basin and Range province to the west. Occupying the southeast corner of the Colorado Plateau is the Datil Section, thick sequences of mid-Tertiary to late-Cenozoic-aged lava covers this section. Development of the province has in part been influenced by structural features in its oldest rocks. Part of the Wasatch Line and its various faults form the edge of the province. Faults that run parallel to the Wasatch Fault that lies along 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 created by movement along structural weaknesses in the regions oldest rock. Some sources also include the Tushar Mountain Plateau as part of the Colorado Plateau, the mostly flat-lying sedimentary rock units that make up these plateaus are found in component plateaus that are between 1500 m to over 3350 m above sea level. A supersequence of these rocks is exposed in the various cliffs, within these rocks are abundant mineral resources that include uranium, coal, petroleum, and natural gas. Study of the unusually clear geologic history has greatly advanced that science. A rain shadow from the Sierra Nevada far to the west, higher areas receive more precipitation and are covered in forests of pine, fir, and spruce
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Basin and Range Province
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The Basin and Range Province is a vast physiographic region that covers much of the inland Western United States and northwestern Mexico. It is defined by unique basin and range topography, characterized by changes in elevation. The physiography of the province is the result of tectonic extension that began around 17 Mya in Early Miocene time, the numerous ranges within the Province in the United States are collectively referred to as the Great Basin Ranges, although many are not actually in the Great Basin. Major ranges include the Snake Range, the Panamint Range, the White Mountains, the Sandia Mountains, pico de Orizaba is unambiguously part of the Trans-Mexican Volcanic Belt which has little in common with the Basin and Range Province. The highest point fully within the Province is White Mountain Peak in California, the Provinces climate is arid, with numerous ecoregions. Most North American deserts are located in the Province, the Basin and Range Province includes much of western North America. The Basin and Range Province extends north to the Columbia Plateau and south as far as the Trans-Mexican Volcanic Belt in Mexico, though the boundaries of the Basin. In Mexico, the Basin and Range Province is dominated by, common geographic features include numerous endorheic basins, ephemeral lakes, plateaus, and valleys alternating with mountains. The area is arid and sparsely populated, although there are several major metropolitan areas, including Mexico City. It is generally accepted that basin and range topography is the result of extension and thinning of the lithosphere, extensional environments like the Basin and Range are characterized by listric normal faulting, or faults that level out with depth. Opposing normal faults link at depth producing a horst and graben geometry, the average crustal thickness of the Basin and Range Province is approximately 30 –35 km and is comparable to extended continental crust around the world. The crust in conjunction with the mantle comprises the lithosphere. The base of the lithosphere beneath the Basin and Range is estimated to be about 60 –70 km, opinions vary regarding the total extension of the region, however, the median estimate is about 100% total lateral extension. Evidence exists to suggest that extension began in the southern Basin and Range. The tectonic mechanisms responsible for extension in the Basin and Range province are controversial. Most of the pertinent tectonic plate movement associated with the Basin and Range Province occurred in Neogene time, by Early Miocene time, much of the Farallon Plate had been consumed, and the seafloor spreading ridge that separated the Farallon Plate from the Pacific Plate approached North America. The movement at this boundary divided the East Pacific Rise and spawned the San Andreas transform fault, today, the Pacific Plate moves north-westward relative to North America, a configuration which has given rise to increased shearing along the continental margin. The tectonic activity responsible for the extension in the Basin and Range is a complex, the most accepted hypothesis suggests that crustal shearing associated with the San Andreas Fault caused spontaneous extensional faulting similar to that seen in the Great Basin
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Coconino County, Arizona
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Coconino County is a county located in the north central part of the U. S. state of Arizona. The population was 134,421 at the 2010 census, the county takes its name from Cohonino, a name applied to the Havasupai. It is the second-largest county by area in the contiguous United States, behind San Bernardino County, California, Coconino County comprises the Flagstaff, AZ Metropolitan Statistical Area. Coconino County contains Grand Canyon National Park, the Havasupai Nation, and parts of the Navajo Nation, Hualapai Nation, and Hopi Nation. It has a relatively large Native American population at nearly 30% of the total population, being mostly Navajo with smaller numbers of Havasupai, Hopi. The county was the setting for George Herrimans early-20th-century Krazy Kat comic strip, after the building of the Atlantic & Pacific Railroad in 1883 the region of northern Yavapai County began experiencing rapid growth. The people of the northern reaches had tired of the rigors of travelling all the way to Prescott for county business and they also believed that they were a significant enough entity that they should have their own county jurisdiction. Therefore, they decided in 1887 to petition for secession from Yavapai and they remained part of Yavapai, however, until 1891 when Coconino County was formed and its seat declared to be Flagstaff. According to the U. S. Census Bureau, the county has an area of 18,661 square miles. It is the largest county by area in Arizona and the second-largest county in the United States after San Bernardino County in California. It has more area than each of the following U. S. states, Connecticut, Delaware, Hawaii, Maryland, Massachusetts, New Hampshire, New Jersey, Rhode Island. The highest natural point in the county, as well as the state, is Humphreys Peak at 12,637 feet or 3,852 metres. The Barringer Meteor Crater is located in Coconino County, the Havasupai Reservation is the only one that lies entirely within the countys borders. As of the 2000 census, there were 116,320 people,40,448 households, the population density was 6 people per square mile. There were 53,443 housing units at a density of 3 per square mile. 10. 94% of the population were Hispanic or Latino of any race,18. 59% reported speaking Navajo at home, while 6. 58% speak Spanish. 22. 10% of all households were made up of individuals and 4. 50% had someone living alone who was 65 years of age or older, the average household size was 2.80 and the average family size was 3.36. In the county, the population was out with 28. 70% under the age of 18,14. 40% from 18 to 24,29. 20% from 25 to 44,20. 70% from 45 to 64
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Grand Canyon
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The Grand Canyon is a steep-sided canyon carved by the Colorado River in the U. S. state of Arizona in North America. President Theodore Roosevelt was a proponent of preservation of the Grand Canyon area. The Grand Canyon is 277 miles long, up to 18 miles wide, since that time, the Colorado River has driven 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 inhabited by Native Americans. The Pueblo people considered the Grand Canyon a holy site, the first European known to have viewed the Grand Canyon was García López de Cárdenas from Spain, who arrived in 1540. It is not the deepest canyon in the world, however, the Grand Canyon is known for its visually overwhelming size and its intricate and colorful landscape. Geologically, it is significant because of the sequence of ancient rocks that are well preserved and exposed in the walls of the canyon. These rock layers record much of the geologic history of the North American continent. Uplift associated with mountain formation later moved these sediments thousands of feet upward, 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 Grand Canyon bisects is over a one thousand feet higher at the North Rim than at the South Rim. Almost all runoff from the North Rim flows toward the Grand Canyon, 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 the South Rim because of the greater elevation, heavy rains are common on both rims during the summer months. Access to the North Rim via the route leading to the canyon 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 40 million years, a recent study places the origins of the canyon beginning about 17 million years ago. Previous estimates had placed the age of the canyon at 5–6 million years, 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. There is an amount of controversy because this research suggests such a substantial departure from prior widely supported scientific consensus. In December 2012, a study published in the journal Science claimed new tests had suggested the Grand Canyon could be as old as 70 million years, the canyon is the result of erosion which exposes one of the most complete geologic columns on the planet. The major geologic exposures in the 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
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Jurassic
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The Jurassic is a geologic period and system that spans 56.3 million years from the end of the Triassic Period 201.3 million years ago to the beginning of the Cretaceous Period 145 Mya. The Jurassic constitutes the middle period of the Mesozoic Era, also known as the Age of Reptiles, the start of the period is marked by the major Triassic–Jurassic extinction event. The Jurassic is named after the Jura Mountains within the European Alps, by the beginning of the Jurassic, the supercontinent Pangaea had begun rifting into two landmasses, Laurasia to the north and Gondwana to the south. This created more coastlines and shifted the continental climate from dry to humid, on land, the fauna transitioned from the Triassic fauna, dominated by both dinosauromorph and crocodylomorph archosaurs, to one dominated by dinosaurs alone. The first birds also appeared during the Jurassic, having evolved from a branch of theropod dinosaurs, other major events include the appearance of the earliest lizards, and the evolution of therian mammals, including primitive placentals. Crocodilians made the transition from a terrestrial to a mode of life. The oceans were inhabited by marine reptiles such as ichthyosaurs and plesiosaurs, the chronostratigraphic term Jurassic is directly linked to the Jura Mountains. The name Jura is derived from the Celtic root jor, which was Latinised into juria, the Jurassic period is divided into the Early Jurassic, Middle, and Late Jurassic epochs. The Jurassic System, in stratigraphy, is divided into the Lower Jurassic, Middle, the separation of the term Jurassic into three sections goes back to Leopold von Buch. The Jurassic North Atlantic Ocean was relatively narrow, while the South Atlantic did not open until the following Cretaceous period, the Tethys Sea closed, and the Neotethys basin appeared. Climates were warm, with no evidence of glaciation, as in the Triassic, there was apparently no land over either pole, and no extensive ice caps existed. In contrast, the North American Jurassic record is the poorest of the Mesozoic, the Jurassic was a time of calcite sea geochemistry in which low-magnesium calcite was the primary inorganic marine precipitate of calcium carbonate. Carbonate hardgrounds were thus very common, along with calcitic ooids, calcitic cements, the first of several massive batholiths were emplaced in the northern American cordillera beginning in the mid-Jurassic, marking the Nevadan orogeny. Important Jurassic exposures are found in Russia, India, South America, Japan, Australasia. As the Jurassic proceeded, larger and more groups of dinosaurs like sauropods and ornithopods proliferated in Africa. Middle Jurassic strata are well represented nor well studied in Africa. Late Jurassic strata are also poorly represented apart from the spectacular Tendaguru fauna in Tanzania, the Late Jurassic life of Tendaguru is very similar to that found in western North Americas Morrison Formation. During the Jurassic period, the primary living in the sea were fish
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Permian
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The Permian is a geologic period and system which spans 46.7 million years from the end of the Carboniferous Period 298.9 million years ago, to the beginning of the Triassic Period 252.2 Mya. It is the last period of the Paleozoic Era, the following Triassic Period belongs to the Mesozoic Era, the concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the city of Perm. The Permian witnessed the diversification of the early amniotes into the groups of the mammals, turtles, lepidosaurs. The world at the time was dominated by two known as Pangaea and Siberia, surrounded by a global ocean called Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior, amniotes, who could better cope with these drier conditions, rose to dominance in place of their amphibian ancestors. The Permian ended with the Permian–Triassic extinction event, the largest mass extinction in Earths history, in which nearly 90% of marine species and it would take well into the Triassic for life to recover from this catastrophe. Recovery from the Permian-Triassic extinction event was protracted, on land, the term Permian was introduced into geology in 1841 by Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil, the region now lies in the Perm Krai of Russia. This could have in part caused the extinctions of marine species at the end of the period by severely reducing shallow coastal areas preferred by many marine organisms. During the Permian, all the Earths major landmasses were collected into a supercontinent known as Pangaea. The Cimmeria continent rifted away from Gondwana and drifted north to Laurasia, a new ocean was growing on its southern end, the Tethys Ocean, an ocean that would dominate much of the Mesozoic Era. Large continental landmass interiors experience climates with extreme variations of heat and cold, deserts seem to have been widespread on Pangaea. Such dry conditions favored gymnosperms, plants with seeds enclosed in a cover, over plants such as ferns that disperse spores in a wetter environment. The first modern trees appeared in the Permian, the climate in the Permian was quite varied. At the start of the Permian, the Earth was still in an Ice Age, glaciers receded around the mid-Permian period as the climate gradually warmed, drying the continents interiors. In the late Permian period, the drying continued although the temperature cycled between warm and cool cycles, Permian marine deposits are rich in fossil mollusks, echinoderms, and brachiopods. By the close of the Permian, trilobites and a host of other groups became extinct. Terrestrial life in the Permian included diverse plants, fungi, arthropods, the period saw a massive desert covering the interior of Pangaea
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Capitol Reef National Park
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Capitol Reef National Park is a United States National Park, in south-central Utah. The park is approximately 60 miles long on its north–south axis, the park was established in 1971 to preserve 241,904 acres of desert landscape and is open all year with May through September being the highest visitation months. Located partially in Wayne County, Utah, the area was originally named Wayne Wonderland in the 1920s by local boosters Ephraim P. Pectol, easy road access only came in 1962 with the construction of State Route 24 through the Fremont River Canyon. The majority of the nearly 100 mi long up-thrust formation called the Waterpocket Fold—a rocky spine extending from Thousand Lake Mountain to Lake Powell—is preserved within the park, Capitol Reef is the name of an especially rugged and spectacular segment of the Waterpocket Fold by the Fremont River. The local word reef refers to any rocky barrier to land travel, Capitol Reef encompasses the Waterpocket Fold, a warp in the earths crust that is 65 million years old. It is the largest exposed monocline in North America, in this fold, newer and older layers of earth folded over each other in an S-shape. This warp, probably caused by the same colliding continental plates that created the Rocky Mountains, has weathered and eroded over millennia to expose layers of rock, the park is filled with brilliantly colored sandstone cliffs, gleaming white domes, and contrasting layers of stone and earth. The fold forms a barrier that even today has barely been breached by roads. Early settlers referred to parallel, impassable ridges as reefs, from which the park gets the half of its name. The first paved road was constructed through the area in 1962, today, State Route 24 cuts through the park traveling east and west between Canyonlands National Park and Bryce Canyon National Park, but few other paved roads invade the rugged landscape. The park is filled with canyons, cliffs, towers, domes, the Fremont River has cut canyons through parts of the Waterpocket Fold, but most of the park is arid desert country. A scenic drive shows park visitors some of the highlights, hundreds of miles of trails and unpaved roads lead the more adventurous into the equally scenic backcountry. Fremont culture Native Americans lived near the perennial Fremont River in the part of the Capitol Reef Waterpocket Fold around the year 1000. They irrigated crops of lentils, maize, and squash and stored their grain in stone granaries, in the 13th century, all of the Native American cultures in this area underwent sudden change, likely due to a long drought. The Fremont settlements and fields were abandoned, many years after the Fremont left, Paiutes moved into the area. These Numic speaking people named the Fremont granaries moki huts and thought they were the homes of a race of people or moki. In 1872 Alan H. Thompson, an attached to United States Army Major John Wesley Powells expedition. Geologist Clarence Dutton later spent several summers studying the areas geology, none of these expeditions explored the Waterpocket Fold to any great extent, however
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Canyonlands National Park
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Canyonlands National Park is a U. S. National Park located in southeastern Utah near the town of Moab. It preserves a colorful landscape eroded into countless canyons, mesas, and buttes by the Colorado River, the Green River, legislation creating the park was signed into law by President Lyndon Johnson on September 12,1964. The park is divided into four districts, the Island in the Sky, the Needles, the Maze, while these areas share a primitive desert atmosphere, each retains its own character. Author Edward Abbey, a frequent visitor, described the Canyonlands as the most weird, wonderful, Canyonlands is a popular recreational destination. Since 2007, more than 400,000 people have visited the park each year with a record of 776,218 visitors in 2016, the geography of the park is well suited to a number of different recreational uses. Hikers, mountain bikers, backpackers, and four-wheelers all enjoy traveling the rugged, the White Rim Road traverses the White Rim Sandstone level of the park between the rivers and the Island in the Sky. Since 2015, day-use permits must be obtained before travelling on the White Rim Road due to the popularity of driving and bicycling along it. The park services intent is to provide a wilderness experience for all visitors while minimizing impacts on the natural surroundings. Rafters and kayakers float the calm stretches of the Green River, below the Confluence, Cataract Canyon contains powerful whitewater rapids, similar to those found in the Grand Canyon. However, since there is no large impoundment on the Colorado River above Canyonlands National Park, river flow through the Confluence is determined by snowmelt, not management. As a result, and in combination with Cataract Canyons unique graben geology, as of 2016, the Island in the Sky district, with its proximity to the Moab, Utah area, attracts 76.7 percent of total park visitors. The Needles district is the second most visited, drawing 20.7 percent of visitors, the remote Maze district accounts for only about 1.5 percent of visitors, while river rafters and other river users account for the remaining 1.1 percent of total park visitation. Political compromise at the time of the parks creation limited the area to an arbitrary portion of the Canyonlands basin. Conservationists hope to complete the park by bringing the boundaries up to the high sandstone rims that form the border of the Canyonlands landscape. The Colorado River and Green River combine within the park dividing it into three districts called the Island in the Sky, the Needles and the Maze, the Colorado River flows through Cataract Canyon below its confluence with the Green River. The area was home of the Ancestral Puebloans, of which many traces can be found. Although the items and tools used have been largely taken away by looters, some of their stone. The Ancestral Puebloans also left traces in the form of petroglyphs, the Maze district is located west of the Colorado and Green rivers, and is the least accessible section of the park, and one of the most remote and inaccessible areas of the United States
26.
Navajo Sandstone
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Navajo Sandstone frequently overlies and interfingers with the Kayenta Formation of the Glen Canyon Group. Together, these formations can result in immense vertical cliffs of up to 2,200 feet, atop the cliffs, Navajo Sandstone often appears as massive rounded domes and bluffs that are generally white in color. Navajo Sandstone frequently occurs as spectacular cliffs, cuestas, domes and it can be distinguished from adjacent Jurassic sandstones by its white to light pink color, meter-scale cross-bedding, and distinctive rounded weathering. The wide range of colors exhibited by the Navajo Sandstone reflect a history of alteration by groundwater and other subsurface fluids over the last 190 million years. The iron in these strata originally arrived via the erosion of iron-bearing silicate minerals, initially, this iron accumulated as iron-oxide coatings, which formed slowly after the sand had been deposited. Later, after having been buried, reducing fluids composed of water. The dissolution of the iron coatings by the reducing fluids bleached large volumes of the Navajo Sandstone a brilliant white, reducing fluids transported the iron in solution until they mixed with oxidizing groundwater. Where the oxidizing and reducing fluids mixed, the iron precipitated within the Navajo Sandstone, the precipitation of iron oxides also formed laminea, corrugated layers, columns, and pipes of ironstone within the Navajo Sandstone. The age of the Navajo Sandstone is somewhat controversial and it may originate from the Late Triassic but is at least as young as the Early Jurassic stages Pliensbachian and Toarcian. There is no type locality of the name and it was simply named for the Navajo Country of the southwestern United States. The two major subunits of the Navajo are the Lamb Point Tongue and the Shurtz Sandstone Tongue, the Navajo Sandstone was originally named as the uppermost formation of the La Plata Group by Gregory and Stone in 1917. Baker reassigned it as the formation of Glen Canyon Group in 1936. Its age was modified by Lewis and others in 1961, the name was originally not used in northwest Colorado and northeast Utah, where the name Glen Canyon Sandstone was preferred. Its age was modified again by Padian in 1989, the sandstone was deposited in an arid erg on the Western portion of the Supercontinent Pangaea. This region was affected by monsoons that came about each winter when cooler winds. Theropod tracks are located in Arizona, Colorado, and Utah. Ornithischian tracks located in Arizona, USA, the Navajo Sandstone is also well known among rockhounds for its hundreds of thousands of iron oxide concretions. They are believed to represent an extension of Hopi Native American traditions regarding ancestor worship, informally, they are called Moqui marbles after the local proposed Moqui Native American tribe
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Kayenta Formation
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Kayenta, Arizona is a settlement in the Navajo reservation. This rock formation is prominent in southeastern Utah, where it is seen in the main attractions of a number of national parks. These include Zion National Park, Capitol Reef National Park, the San Rafael Swell, the Kayenta Formation frequently appears as a thinner dark broken layer below Navajo Sandstone and above Wingate Sandstone. Together, these three formations can result in immense vertical cliffs of 2,000 feet or more, Kayenta layers are typically red to brown in color, forming broken ledges. In most sections that include all three formations of the Glen Canyon group the Kayenta is easily recognized. Even at a distance it appears as a dark-red, maroon and its position is also generally marked by a topographic break. Its weak beds form a bench or platform developed by stripping the Navajo sandstone back from the face of the Wingate cliffs, the Kayenta is made up of beds of sandstone, shale, and limestone, all lenticular, uneven at their tops, and discontinuous within short distances. They suggest deposits made by shifting streams of fluctuating volume, the sandstone beds, from less than 1-inch to more than 10 feet thick, are composed of relatively coarse, well-rounded quartz grains cemented by lime and iron. The thicker beds are indefinitely cross bedded, the shales are essentially fine-grained, very thin sandstones that include lime concretions and balls of consolidated mud. The limestone appears as solid gray-blue beds, a few inches to a few feet thick, most of the limestone lenses are less than 25 feet long, but two were traced for nearly 500 feet and one for 1,650 feet. Viewed as a whole, the Kayenta is readily distinguished from the formations above. It is unlike them in composition, color, manner of bedding, but in many sections the contact between the two formations is unconformable, the basal Kayenta consists of conglomerate and lenticular sandstone that fills depressions eroded in the underlying beds. In Moqui Canyon near Red Cone Spring nearly 10 feet of Kayenta limestone conglomerate rests in a long meandering valley cut in Wingate. The red and mauve Kayenta siltstones and sandstones that form the slopes at base of the Navajo Sandstone cliffs record the record of low to moderate energy streams, poole has shown that the streams still flowed toward the east depositing from 150 to 210 m of sediment here. The sedimentary structures showing the channel and flood deposits of streams are well exposed on switchbacks below the tunnel in Pine Creek Canyon. In the southeastern part of Zion National Park a stratum of cross bedded sandstone is roughly halfway between the top and bottom of the Kayenta Formation. It is a tongue of sandstone that merges with the Navajo formation east of Kanab and this tongue is the ledge that shades the lower portion of the Emerald Pool Trail, and it is properly called Navajo, not Kayenta. Fossil mudcracks attest to seasonal climate, and thin limestones and fossilized trails of aquatic snails or worms mark the existence of ponds
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Wingate Sandstone
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The Wingate Sandstone is a geologic formation in the Glen Canyon Group of the Colorado Plateau province of the United States outcropping in northern Arizona, northwest Colorado, Nevada, and Utah. Wingate Sandstone is particularly prominent in southeastern Utah, where it forms attractions in a number of national parks and these include Capitol Reef National Park, the San Rafael Swell, and Canyonlands National Park. Wingate sandstone frequently appears just below the Kayenta Formation and Navajo Sandstone, together, these three formations can result in immense vertical cliffs of 2000 feet or more. Wingate layers are pale orange to red in color, the remnants of wind-born sand dunes deposited approximately 200 million years ago in the Late Triassic. Long dated to the Early Jurassic only, fossils and other evidence indicate that part of the Wingate Sandstone is as old as Late Triassic in age, the upper part of the formation, which laterally interfingers with the Moenave Formation to the west, is Early Jurassic in age. U. S. G. S Lexicon of Colorado Plateau Stratigraphy
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Chinle Formation
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The Chinle is controversially considered to be synonymous to the Dockum Group of eastern Colorado and New Mexico, western Texas, the Oklahoma panhandle, and southwestern Kansas. The Chinle is sometimes named as a formation within the Dockum Group in New Mexico. The Chinle Formation is part of the Colorado Plateau, Basin and Range, a probable separate depositional basin within the Chinle is found in northwestern Colorado and northeastern Utah. The southern portion of the Chinle reaches a thickness of a little over 520 m. Typically, the Chinle rests unconformably on the Moenkopi Formation, there is no designated type locality for this formation. United States Geological Survey economic geologist Raymond C, robeck in 1956 revised the unnamed members of Gregory by identifying and naming the Temple Mountain member as the basal-most unit in the area of the San Rafael Swell of Utah. In 1957 John H. Stewart revised the Shinarump Conglomerate of G. K. Gilbert,1875, and Edwin E. Howell,1875, and Gregory,1917, and renamed it the Shinarump member of the Chinle formation. An overview of the geology of the area was created by USGS geologist Forrest G. Poole, sikich revised the unit and assigned more members assigned in 1965. The areal extent of the unit was mapped by Wilson and Stewart in 1967, in 1972 the areal limits were modified and an overview created by Stewart and others. Kelley assigned more members and revised the unit in 1972, Lucas and Hayden did the same thing in 1989. The Rock Point Member was assigned by Dubiel in 1989, the Chinle was raised to group status by Lucas in 1993, thus also raising many of the members to formation status. He also included the formations of the Dockum Group of eastern New Mexico and this modified nomenclature is controversial, many still retain the Chinle as a formation and separate out the Dockum Group. The Dockum was named in 1890, before the Chinle, if Lucas is correct, his Chinle Group should be named the Dockum Group due to stratigraphic nomenclature rules. Overviews of the Chinle were created by Dubiel and others and Hintze, the formation members and their thicknesses are highly variable across the Chinle. The stratigraphically lowest formation is the Temple Mountain Member, however, in most areas, the basal member is the Shinarump Member. The Shinarump is a braided-river system channel-deposit facies, the Monitor Butte Member overlies the Shinarump in most areas. The Monitor Butte is an overbank facies with lacustrine deposits and this is overlain in western areas by the channel-deposit facies Moss Back Member. More commonly, the Monitor Butte grades into the Petrified Forest Member, the Petrified Forest is predominately overbank deposits with thin lenses of channel-deposit facies and lacustrine deposits
30.
Cutler Formation
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The Cutler Formation or Cutler Group is a rock unit that is spread across the U. S. states of Arizona, northwest New Mexico, southeast Utah and southwest Colorado. It was laid down in the Early Permian during the Wolfcampian stage and its subunits, therefore, are variously called formations or members depending on the publication. Members, De Chelly Sandstone White Rim Sandstone Organ Rock Shale Cedar Mesa Sandstone Elephant Canyon Formation Halgaito Shale - There is no designated type locality for the Cutler. It was named by Cross and Howe in 1905 after Cutler Creek, baker and Reeside revised Cross and Howes work in 1929 by dividing the formation into the Halgaito Tongue, Cedar Mesa Sandstone Member, Organ Rock Tongue, and White Rim Sandstone Member. Cutlers geographic extent was established by Wood and Northrop in 1946, in 1958 Wengerd and Matheny raised the formation to group rank. Cutler outcrops are found in these locations in Arizona, Colorado, New Mexico. 1958, Pennsylvanian system of the Four Corners region, American Association of Petroleum Geologists Bulletin, v.42, no
31.
Glen Canyon National Recreation Area
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The Glen Canyon NRA was established in 1972 to provide for public use and enjoyment and to preserve the areas scientific, historic, and scenic features. The stated purpose of Glen Canyon NRA is for recreation as well as preservation, as such, the area has been developed for access to Lake Powell via 5 marinas,4 camping grounds, two small airports, and houseboat rental concessions. The southwestern end of Glen Canyon NRA in Arizona can be accessed via U. S. Route 89, State Route 95 and State Route 276 lead to the northeastern end of the recreation area in Utah. The current Lake Powell lies above Glen Canyon, which was flooded by the Glen Canyon Dam, completed in 1966. Lake Powell has nearly 2,000 miles of fish-holding shoreline and provides opportunity to fish for bass, smallmouth bass. Lake Powell National Golf Course Championship is an 18-hole course sitting on a mesa overlooking the Glen Canyon Dam, Lake Powell. Several local marinas provide houseboats, powerboats, jet skis, kayaks, fishing gear, the Geology of the area is dominated by the Glen Canyon Group, consisting of the Navajo Sandstone, Kayenta Formation, and Wingate Sandstone. The entire stratigraphic section included rocks dating from the Cretaceous to Pennsylvanian, with over one million visitors per year, it is inevitable that some will deface the rock faces of the canyon. The Glen Canyon NRA has implemented a program wherein volunteers sign up for a five-day houseboat trip to remove graffiti from the canyon walls
32.
Great Basin
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The Great Basin is the largest area of contiguous endorheic watersheds in North America. The region spans several physiographic divisions, biomes/ecoregions, and deserts, the term Great Basin is applied to hydrographic, biological, floristic, physiographic, topographic, and ethnographic geographic areas. The name was coined by John C. Frémont, who, based on information gleaned from Joseph R. Walker as well as his own travels, the hydrographic definition is the most commonly used, and is the only one with a definitive border. The other definitions yield not only different geographical boundaries of Great Basin regions, the Great Basin physiographic section is a geographic division of the Basin and Range Province defined by Nevin Fenneman in 1931. The United States Geological Survey adapted Fennemans scheme in their Physiographic division of the United States, the section is somewhat larger than the hydrographic definition. The culture area covers approximately 400,000 sq mi, or just less than twice the area of the hydrographic Great Basin, the hydrographic Great Basin is a 209,162 square miles area that drains internally. All precipitation in the region evaporates, sinks underground or flows into lakes, as observed by Frémont, creeks, streams, or rivers find no outlet to either the Gulf of Mexico or the Pacific Ocean. The region is bounded by the Wasatch Mountains to the east, the Sierra Nevada and Cascade Ranges to the west, the south rim is less distinct. The Great Basin includes most of Nevada, half of Utah, substantial portions of Oregon and California and small areas of Idaho, Wyoming, the term Great Basin is slightly misleading, the region is actually made up of many small basins. The Great Salt Lake, Pyramid Lake, and the Humboldt Sink are a few of the drains in the Great Basin, the Salton Sink is another closed basin within the Great Basin. The Great Basin Divide separates the Great Basin from the watersheds draining to the Pacific Ocean, the southernmost portion of the Great Basin is the watershed area of the Laguna Salada. The Great Basins longest and largest river is the Bear River of 350 mi, Lake Tahoe, North Americas largest alpine lake, is part of the Great Basins central Lahontan subregion. The hydrographic Great Basin contains multiple deserts and ecoregions, each with its own set of flora. The ecological boundaries and divisions in the Great Basin are unclear, the Great Basin overlaps four different deserts, portions of the hot Mojave and Colorado Deserts to the south, and the cold Great Basin and Oregon High Deserts in the north. The deserts can be distinguished by their plants, the Joshua tree and creosote bush occur in the hot deserts, the cold deserts are generally higher than the hot, and have their precipitation spread throughout the year. The climate and flora of the Great Basin is strongly dependent on elevation, as the elevation increases, because of this, forests occur at higher elevations. Utah juniper/single-leaf pinyon and mountain mahogany form open pinyon-juniper woodland on the slopes of most ranges, stands of limber pine and Great Basin bristlecone pine can be found in some of the higher ranges
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Green River (Colorado River tributary)
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The Green River, located in the western United States, is the chief tributary of the Colorado River. The watershed of the river, known as the Green River Basin, covers parts of Wyoming, Utah, and Colorado. The Green River is 730 miles long, beginning in the Wind River Mountains of Wyoming and flowing through Wyoming and Utah for most of its course, much of the route is through the Colorado Plateau and through some of the most spectacular canyons in the United States. It is only smaller than the Colorado when the two rivers merge, but typically carries a larger load of silt. The average yearly mean flow of the river at Green River, the status of the Green River as a tributary of the Colorado River came about for mainly political reasons. In earlier nomenclature, the Colorado River began at its confluence with the Green River, above the confluence the Colorado was called the Grand River. Representative Edward T. Taylor petitioned the Congressional Committee on Interstate and it rises in western Wyoming, in northern Sublette County, on the western side of the Continental Divide in the Bridger-Teton National Forest in the Wind River Range. It flows south through Sublette County and western Wyoming in a known as the Upper Green River Valley. At the town of La Barge, it flows into Fontenelle Reservoir, prior to the creation of the reservoir, the Blacks Fork joined the Green River south of Green River, today the mouth of Blacks Fork is submerged by the reservoir. It turns westward back into Utah along the edge of the Uintas in Whirlpool Canyon. In Utah it meanders southwest across the Yampa Plateau and through the Uintah and Ouray Indian Reservation, two miles south of Ouray, Utah, it is joined by Duchesne River, and three miles downstream by the White River. Ten miles farther downstream it is joined by the Willow River, south of the plateau, it is joined by Nine Mile Creek, then enters the Roan Cliffs where it flows south through the back-to-back Desolation and Gray Canyons, with a combined length of 120 mi. In Gray Canyon, it is joined by the Price River, south of the canyon it passes the town of Green River, Utah and is joined by the San Rafael River in southern Emery County. In eastern Wayne County it meanders through Canyonlands National Park where it joins the Colorado, the Flaming Gorge Dam in Utah is a significant regional source of water for irrigation and mining, as well as for hydroelectric power. Begun in the 1950s and finished in 1963, it was highly controversial, originally, a dam was to be built in Whirlpool Canyon, but the conservationist movement traded the Flaming Gorge dam for halting that proposal. Apocryphally, the Sierra Club, an environmental organization, lost its tax-exempt status for political action in opposing the proposed dam. The Green is a large, deep, powerful river and it ranges from 100 to 300 feet wide in the upper course to 300 to 1,500 feet wide in its lower course and ranges from 3 to 50 feet in depth. It is navigable by small craft throughout its course and by large motorboats upstream to Flaming Gorge Dam, near the areas where the Oregon Trail crosses, the river is 400 -500 feet wide and averages about 20 feet deep at normal flow
34.
Paradox Basin
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The Paradox Basin 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 on the west by the Circle Cliffs Uplift. Its areal size is around 33,000 square miles, the combined sedimentary strata of the Paradox Basin are more than 15,000 feet thick in some places. Unlike most Rocky Mountain basins, the Paradox Basin is a basin containing sediments from alternating cycles of deep marine. Natural resources extracted from the basin include petroleum, uranium, copper, 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 age Leadville Limestone, the Pennsylvanian Age Hermosa Group and the Permian age Cutler Formation. Discoveries in the cane creek formation have resulted in new oil production in the cane creek unit, near Moab, Paradox Valley, which gave the basin its name
35.
Piceance Basin
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The Piceance Basin is a geologic structural basin in northwestern Colorado, in the United States. It includes geologic formations from Cambrian to Holocene in age, the basin contains reserves of coal, natural gas, and oil shale. The basin has come to increasing attention in recent years because of widespread drilling to extract natural gas. The primary target of gas development has been the Williams Fork Formation of the Mesaverde Group, the Williams Fork is a several-thousand-foot thick section of shale, sandstone and coal deposited in a coastal plain environment. The formation has long known to contain natural gas. The sandstone reservoirs have low permeability and limited extent, however. Project Rulison, as it was called, was a failure, advances in hydraulic fracturing within the past decade, along with higher gas prices, have made gas wells broadly economic in the area. In 2007 the basin contained five of the top 50 US gas fields in proved reserves, increased gas drilling in recent years has been criticized by some. There is strong criticism of drilling for gas in previously undeveloped areas such as the Roan Plateau, increasing demand for energy resources has spurred interest in energy alternatives such as oil shale. The Piceance Basin contains one of the thickest and richest oil shale deposits in the world and is the focus of most on-going oil shale research, the Piceance Basin has an estimated 1.525 trillion barrels of in-place oil shale resources. This studyalso found an estimated 43.3 billion tons of in-place nahcolite resources in the Piceance Basin and this mineral is embedded with oil shale in many areas. On 2 April 2009 The U. S. Geological Survey updated its assessment of in-place oil shale resources in the Piceance Basin in western Colorado and this new assessment is about 50 percent larger than the 1989 assessment of about one trillion barrels. Almost all of this increase is due to assessments of new areas and subsurface zones that had too little data for previous research. For the first time in 20 years, we have an assessment of in-place oil shale in the Piceance Basin of Colorado. The USGS scientific report shows significant quantities of oil locked up in the rocks of the Piceance Basin. I believe it demonstrates the need for our research and development efforts. Oil is obtained when oil shale rock is heated to 530° to 930 °F and these temperatures are required because oil shale does not contain crude oil but instead contains kerogen, which is an organic precursor to oil that must be heated for oil production. The United States Geological Survey has researched the geology of oil shale, especially the extensive Green River deposits of Colorado, Utah, and Wyoming
36.
San Juan Basin
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The San Juan Basin is a geologic structural basin located near the Four Corners region of the Southwestern United States. The basin covers 7,500 square miles and resides in northwestern New Mexico, southwestern Colorado, specifically, the basin occupies space in the San Juan, Rio Arriba, Sandoval, and McKinley counties in New Mexico, and La Plata and Archuleta counties in Colorado. The basin extends roughly 100 miles N-S and 90 miles E-W, the San Juan Basin is an asymmetric structural depression in the Colorado Plateau province, with varying elevation and nearly 3,000 in topographic relief. Its most striking features include Chaco Canyon and Chacra Mesa, the basin lies west of the Continental Divide, and its main drainage is the southwest- to west-flowing San Juan River, which eventually joins the Colorado River in Utah. Climate of the basin is arid to semiarid, with a precipitation of 15 inches. The San Juan Basin has been a producer of oil and natural gas since the early 20th century, with currently more than 300 oil fields. As of 2009, cumulative production reached 42.6 trillion cubic feet of gas and 381 million barrels of oil, the area is especially known for gas reservoirs from its coal-bed methane formations. The San Juan Basin contains the largest coal-bed methane field in the world, during the mid-Paleozoic, the San Juan Basin was part of the ancient landmass called Laurentia, this was a supercontinent that contained much of current-day North America. The ancient landmass called Gondwana contained most of the southern continents, during the late-Mississippian, the landmasses of Laurentia and Gondwana collided to form the giant landmass of Pangea. This continental collision resulted in several pivotal orogenic episodes, the collision of supercontinents Gondwana and Laurentia resulted in the Alleghanian and Ouachita orogenies. The Alleghanian Orogeny was the collision of Africa with the current-day southeastern United States, the Ancestral Rockies gave way to the Uncompahgre Mountain Range, which bound the San Juan Basin on the northeast. During the late Jurassic, continental collision of the Farallon and North American plates resulted in low-angle subduction beneath the western margin of the United States. Pressure on the underlying lithosphere resulting in a depression of the interior. During late-Cretaceous to early-Tertiary, compressional forces continued to act and caused the uplift of the modern Rocky Mountains via the Laramide Orogeny, early-Tertiary tilting towards the northwest resulted in over 2,000 of erosion in the southeast. As compression shifted to extension and the formation of the Rio Grande Rift began, Uplift in the northwest and continued deposition brought the basin to its current-day configuration. The San Juan Basin is a syncline with three components, the Central Basin Platform, the Four Corners Platform, and the Chaco Slope. The basin is bound on the northwest by the Hogback Monocline, on the northeast by the Archuleta Anticlinorium, on the east by the Nacimiento Uplift, the Permian continued to be a time of terrestrial deposits, including late-Permian eolian deposits. The Cretaceous was a time of three major transgressive-regressive cycles, as changes in sea-level caused fluctuations on the Western Interior Seaways shoreline
37.
Uintah Basin
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The Uinta Basin, is a physiographic section of the larger Colorado Plateaus province, which in turn is part of the larger Intermontane Plateaus physiographic division. It is also a structural basin in eastern Utah, east of the Wasatch Mountains. The Uinta Basin is fed by creeks and rivers flowing south from the Uinta Mountains, many of the principal rivers flow into the Duchesne River which feeds the Green River—a tributary of the Colorado River. The Uinta Mountains forms the border of the Uinta Basin. They contain the highest point in Utah, Kings Peak, with a summit 13,528 feet above sea level, the climate of the Uinta Basin is semi-arid, with occasionally severe winter cold. Father Escalantes expedition visited the Uinta Basin in September 1776, the Northern Ute Indian Reservation was established in 1861 by presidential decree. The United States opened the reservation for homesteading by non-Native Americans in 1905, the largest community in the Utah part of the Uinta Basin is Vernal. According to the U. S. Census, the population in 2010 was 9,089. Other communities in the Utah part of the region include Duchesne, Roosevelt, Altamont, Tabiona, the Uinta Basin is also the location of the Uintah and Ouray Indian Reservation, home to the Ute Tribe of the Uinta and Ouray Agency. The Ute Tribe is the source of Utahs state name, local attractions include Dinosaur National Monument, Starvation Reservoir State Park, Flaming Gorge National Recreation Area, Raven Ridge and Fantasy Canyon. The local economy, once based on agriculture and mining, has diversified, in order to move oil out of the region, a new railroad is proposed to be constructed into the basin. In addition, Utah State University operates Branch campuses at Vernal and Roosevelt, the Uintah Basin is the most northerly section of the Colorado Plateau sections. The basin is 5,000 to 10,000 ft above sea level, on the south side of the plateau the descent of 3,000 ft, to the general level of eastern Utah on the south, is made in two steps. The first is the Roan Cliffs and the second, the Book Cliffs, eastward in Colorado the two lines of cliffs are poorly distinguished. The Green River flows southward out of the Uinta Mountains to the north, crossing the Uintah Basin, the Uintah Basin forms a geologic structural basin, and is the source of commercial oil and gas production. Population, Housing Units, Area, and Density,2000, U. S. Census Bureau Utah History to Go The Uintah Basin Standard Utah State University, Uintah Basin Campus Uinta Basin
38.
Grand Canyon National Park
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Grand Canyon National Park is the United States 15th oldest national park. Named a UNESCO World Heritage Site in 1979, the park is located in northwestern Arizona, the parks central feature is the Grand Canyon, a gorge of the Colorado River, which is often considered one of the Seven Natural Wonders of the World. The park covers 1,217,262 acres of unincorporated area in Coconino, the park received nearly six million recreational visitors in 2016, which is the second highest count of all U. S. national parks after Great Smoky Mountains National Park. Grand Canyon was officially designated a park in 1919, though the landmark had been well known to Americans for over thirty years prior. In 1903, President Theodore Roosevelt visited the site and said and it is beyond comparison—beyond description, absolutely unparalleled through-out the wide world. Let this great wonder of nature remain as it now is, do nothing to mar its grandeur, sublimity and loveliness. But what you can do is to keep it for children, your childrens children. Despite Roosevelts enthusiasm and his strong interest in preserving land for public use, harrison unsuccessfully reintroduced his bill in 1883 and 1886, after his election to the presidency, he established the Grand Canyon Forest Reserve in 1893. Theodore Roosevelt created the Grand Canyon Game Preserve by proclamation on 28 November 1906, the National Park Service, established in 1916, assumed administration of the park. The creation of the park was a success of the conservation movement. Its national park status may have helped thwart proposals to dam the Colorado River within its boundaries, in 1975, the former Marble Canyon National Monument, which followed the Colorado River northeast from the Grand Canyon to Lees Ferry, was made part of Grand Canyon National Park. In 1979, UNESCO declared the park a World Heritage Site, in 2010, Grand Canyon National Park was honored with its own coin under the America the Beautiful Quarters program. The Grand Canyon, including its system of tributary canyons, is valued for its combination of size, depth. The canyon itself was created by the incision of the Colorado River and its tributaries after the Colorado Plateau was uplifted, the primary public areas of the park are the North and South Rims of the Grand Canyon itself. The rest of the park is rugged and remote, although many places are accessible by pack trail. Only the Navajo Bridge near Page connects the rims by road in Arizona, otherwise, the two rims of the Canyon are connected via the Mike OCallaghan–Pat Tillman Memorial Bridge and the Hoover Dam. The park headquarters are at Grand Canyon Village, not far from the entrance to the park. Park accommodations are operated by Xanterra Parks and Resorts, the North Rim is a smaller, more remote area with less tourist activity
39.
Monument Valley
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Monument Valley is a region of the Colorado Plateau characterized by a cluster of vast sandstone buttes, the largest reaching 1,000 ft above the valley floor. It is located on the Arizona–Utah border, near the Four Corners area, the valley lies within the range of the Navajo Nation Reservation and is accessible from U. S. Highway 163. Monument Valley has been featured in many forms of media since the 1930s, the area is part of the Colorado Plateau. The elevation of the valley ranges from 5,000 to 6,000 feet above sea level. The floor is largely siltstone of the Cutler Group, or sand derived from it, the valleys vivid red color comes from iron oxide exposed in the weathered siltstone. The darker, blue-gray rocks in the valley get their color from manganese oxide, the buttes are clearly stratified, with three principal layers. The lowest layer is the Organ Rock Shale, the middle is de Chelly Sandstone, the valley includes large stone structures including the famed Eye of the Sun. Monument Valley is officially a large area includes much of the area surrounding Monument Valley Navajo Tribal Park. Oljato, for example, is also within the designated as Monument Valley. Visitors may pay a fee and drive through the park on a 17-mile dirt road. Parts of Monument Valley, such as Mystery Valley and Hunts Mesa, are only by guided tour. Monument Valley experiences a climate with cold winters and hot summers. While the summers may be hot, the heat is tempered by the high altitude. Although the valley experiences an average of 54 days above 90 °F annually, summer nights are comfortably cool, and temperatures drop quickly after sunset. Winters are cold, but daytime highs are usually above freezing, even in the winter, temperatures below 0 °F are uncommon, though possible. Monument Valley receives a light snowfall in the winter, however. Monument Valley has been featured in computer games, films. Valley of the Gods Thomas J
40.
Navajo Nation
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This is the largest land area retained by a U. S. tribe, with a total population of 173,667. The original territory has expanded several times since the 1800s. In 2016 under the Tribal Nations Buy-Back Program, some 149,524 acres of land were returned by the Department of Interior to the Navajo Nation for tribal communal use, the program is intended to help restore the land bases of reservations. The executive system manages a large law enforcement and social services apparatus, health services, Diné College, the population continues to disproportionately struggle with health problems, unemployment, and the effects of past uranium mining accidents. In English, the name for the area was Navajo Indian Reservation. On April 15,1969, the changed its official name to the Navajo Nation. This was a period of Native American activism and assertion of sovereignty, in 1994, the Tribal Council rejected a proposal to change the official designation from Navajo to Diné. It was remarked that the name Diné represented the time of suffering before the Long Walk, in Navajo, the geographic entity with its legally defined borders is known as Naabeehó Bináhásdzo. This contrasts with Diné Bikéyah and Naabeehó Bikéyah for the idea of Navajoland. Neither of these terms should be confused with Dinétah, the used for the traditional homeland of the Navajo. It is situated in the area among the four sacred Navajo mountains of Dookʼoʼoosłííd, Dibé Ntsaa, Sisnaajiní, the Navajo peoples tradition of governance is rooted in their clans and oral history. The clan system of the Diné is integral to their society, singer argues in 2007s Government Reform Project. In the mid-19th century, the Navajo were forced from their lands by the US Army following defeat, after they were allowed to return, the Navajo Indian Reservation was established according to the Treaty of 1868 with the United States. Though the treaty had provided for one hundred miles in the New Mexico Territory. This initial piece of land is represented in the design of the Navajo Nations flag by a dark-brown rectangle, as no physical boundaries or signposts were set in place, many Navajo ignored these formal boundaries and returned to where they had been living prior to captivity. A significant population of Navajo still resided along the Little Colorado and Colorado rivers and they had never lived in the Hwéeldi near. The first expansion of the territory occurred on October 28,1878, further additions followed throughout the late 19th and early 20th century. The eastern border was shaped primarily as a result of allotments of land to individual households under the Dawes Act of 1887, the government determined that land left over after all members had received allotments was to be considered surplus and available for sale to non-Native Americans
41.
Dinosaur National Monument
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Dinosaur National Monument is a U. S. National Monument located on the southeast flank of the Uinta Mountains on the border between Colorado and Utah at the confluence of the Green and Yampa Rivers. Although most of the monument area is in Moffat County, Colorado, the nearest communities are Jensen, Utah and Dinosaur, Colorado. This park contains over 800 paleontological sites and has fossils of dinosaurs including Allosaurus, Deinonychus, Abydosaurus and various long-neck and it was declared a National Monument on October 4,1915. The rock layer enclosing the fossils is a sandstone and conglomerate bed of alluvial or river bed known as the Morrison Formation from the Jurassic Period some 150 million years old. The dinosaurs and other ancient animals were carried by the system which eventually entombed their remains. The pile of sediments were buried and lithified into solid rock. The layers of rock were later uplifted and tilted to their present angle by the mountain building forces that formed the Uintas during the Laramide orogeny, the relentless forces of erosion exposed the layers at the surface to be found by paleontologists. The dinosaur fossil beds were discovered in 1909 by Earl Douglass and he and his crews excavated thousands of fossils and shipped them back to the museum in Pittsburgh, Pennsylvania for study and display. President Woodrow Wilson proclaimed the dinosaur beds as Dinosaur National Monument in 1915, though lesser-known than the fossil beds, the petroglyphs in Dinosaur National Monument are another treasure the monument holds. Due to problems with vandals, many of the sites are not listed on area maps, the controversy assumed major proportions, dominating conservation politics for years. They argued that, if a national monument was not safe from development, after much debate, Congress settled on a compromise that eliminated Echo Park Dam and authorized the rest of the project. The Colorado River Storage Project Act became law on April 11,1956. It stated, “that no dam or reservoir constructed under the authorization of the Act shall be within any National Park or Monument. ”Historians view the Echo Park Dam controversy as signaling the start of an era that includes major conservationist political successes such as the Wilderness Act and the Wild and Scenic Rivers Act. Mantles Cave is a prehistoric Fremont culture residential site from 499 BC - AD1749, typical of high deserts, summer temperatures can be exceedingly hot, while winter temperatures can be very cold. Snowfall is common, but the snow melts rapidly in the arid, rainfall is very low, and the evaporation rate classifies the area as desert, even though the rainfall just barely exceeds 10 inches. The Wall of Bones located within the Dinosaur Quarry building in the consists of a steeply tilted rock layer which contains hundreds of dinosaur fossils. The enclosing rock has been chipped away to reveal the fossil bones intact for public viewing, in July 2006, the Quarry Visitor Center was closed due to structural problems that since 1957 had plagued the building because it was built on unstable clay. It was announced in April 2009 that Dinosaur National Monument would receive $13.1 million to refurbish, the Park Service successfully rebuilt the Quarry Exhibit Hall, supporting its weight on 70-foot steel micropile columns that extend to the bedrock below the unstable clay
42.
Walnut Canyon National Monument
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Walnut Canyon National Monument is a United States National Monument located about 10 mi southeast of downtown Flagstaff, Arizona, near Interstate 40. The canyon rim elevation is 6,690 ft, the floor is 350 ft lower. Other contemporary habitations of the Sinagua people are preserved in the nearby Tuzigoot, Sinagua is Spanish for without water, an acknowledgement that the Sinagua people were able to live in such a dry region. By living in such a region the Sinagua became experts at conserving water, the Sinagua were also believed to have been active traders that stretched to the Gulf of Mexico and even as far as Central America. The Sinagua, who inhabited the dwellings in Walnut Canyon, left mysteriously around 1250 CE and it is thought that the Sinagua left because of fear of neighboring tribes or droughts, but it is not certain. The Sinagua left over 80 cliff dwellings behind, the dwellings themselves were small, but large enough for the inhabitants to cook and sleep. Most of the dwelling rooms are situated near the loop trail, typically slightly above the trail. A typical room might have been the dwelling of a single family, because of the areas dry climate, the water present in the canyon was essential for its inhabitants over 700 years ago as it is for animal and plant life today. The plant life is diverse in Walnut Canyon, with more than 387 different plant species, including the Prickly Pear cactus. The biodiversity of the area includes high concentrations of plant species that probably contributed to the decision made by prehistoric people to settle in the area. There are other ruins in the 20-by-10-mile area, but none are publicly accessible, many more dwellings to be seen up close in the canyon just east of the Monument, although it is illegal to enter the canyon. Walnut Canyon was proclaimed a monument on November 30,1915 by President Woodrow Wilson to preserve the ancient cliff dwellings. It was transferred from the USDA Forest Service to the National Park Service on August 10,1933, as with all historic areas administered by the National Park Service, the national monument was listed on the National Register of Historic Places on October 15,1966. At Walnut Canyon, there are trails for tourists to get a view of the dwellings. Walnut Canyon lies on the Colorado Plateau and cuts through the Permian Kaibab Limestone, the Kaibab formation also forms the rim of the Grand Canyon. Crossbedding is present in the Coconino Sandstone, the Walnut Canyon site contains Walnut Creek, which carved a 600 foot deep canyon that flows east. The creek joins into the Little Colorado River en route to the Grand Canyon, the creek has also created a varied and abundant array of vegetation. The shaded, north- facing walls are covered in fir and ponderosa pine trees, the sunny, south facing slopes have agaves and several species of cactus including opuntia, echnocereus and cholla
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Wupatki National Monument
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The Wupatki National Monument is a U. S. National Monument located in north-central Arizona, near Flagstaff. Rich in Native American ruins, the monument is administered by the National Park Service in close conjunction with the nearby Sunset Crater Volcano National Monument, Wupatki was listed on the National Register of Historic Places on October 15,1966. The listing included three contributing buildings and 29 contributing structures on 35,253.2 acres, the many settlement sites scattered throughout the monument were built by the Ancient Pueblo People, more specifically the Cohonina, Kayenta Anasazi, and Sinagua. Wupatki was first inhabited around 500 AD, nearby secondary structures have also been uncovered, including two kiva-like structures. By 1182, approximately 85 to 100 people lived at Wupatki Pueblo but by 1225, based on a careful survey of archaeological sites conducted in the 1980s, an estimated 2000 immigrants moved into the area during the century following the eruption. Agriculture was based mainly on maize and squash raised from the land without irrigation. In the Wupatki site, the residents harvested rainwater due to the rarity of springs, the dwellings walls were constructed from thin, flat blocks of the local Moenkopi sandstone giving the pueblos their distinct red color. Held together with mortar, many of the walls still stand, each settlement was constructed as a single building, sometimes with scores of rooms. The largest settlement on monument territory is the Wupatki Ruin, built around a rock outcropping. With over 100 rooms, this ruin is believed to be the areas tallest and largest structure for its time period and this site also contains a geological blowhole. Other major sites are Wukoki and The Citadel, today Wupatki appears empty and abandoned, but it is remembered and cared for. Though it is no longer occupied, Hopi believe the people who lived and died here remain as spiritual guardians. Stories of Wupatki are passed on among Hopi, Navajo, Zuni, members of the Hopi Bear, Katsina, Lizard, Rattlesnake, Sand, Snow, and Water Clans return periodically to enrich their personal understanding of their clan history. Wupatki Ruins In James Rollins seventh Sigma Force novel The Devil Colony, Painter Crowe takes a contingent to explore Sunset Crater, during the course of their preparations and explorations, the group discusses the history of the people and geology at the two sites. AZ-152-A, Wupatki, Wupatki Ruin, U. S. Highway 89, Loop Road, Flagstaff vicinity, Coconino County, aZ-152-B, Wupatki, Wukoki Ruin, U. S. Highway 89, Loop Road, Flagstaff vicinity, Coconino County, AZ HABS No. AZ-152-C, Wupatki, Citadel Ruin, U. S. Highway 89, Loop Road, Flagstaff vicinity, Coconino County, aZ-152-D, Wupatki, Ball Court, U. S. Highway 89, Loop Road, Flagstaff vicinity, Coconino County, AZ
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Basal (phylogenetics)
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In phylogenetics, basal is the direction of the base of a rooted phylogenetic tree or cladogram. Clade C may be described as basal within a larger clade D if its root is linked to the root of D. If C is a clade within D that has the lowest taxonomic rank of all basal clades within D, C may be described as the basal taxon of that rank within D. While there must always be two or more equally basal clades sprouting from the root of every cladogram, those clades may differ widely in rank or species diversity. In general, clade A is more basal than clade B if B is a subgroup of the group of A. Within large groups, basal may be used loosely to mean closer to the root than the great majority of. A core clade is a clade representing all but the clade of lowest rank within a larger clade. While basal applies to clades, characters or traits are considered derived if they are absent in a basal group. This assumption only holds if the basal group is a good analogy for the last common ancestor of the group. Ancestral or plesiomorphic are preferred to primitive, which may carry false connotations of inferiority or a lack of complexity, within the primate family Hominidae, gorillas are a sister group to common chimpanzees, bonobos and humans. These five species form a clade, the subfamily Homininae, of which Gorilla is the basal genus, however, if the analysis is not restricted to genera, the Homo plus Pan clade is also basal. This semantic ambiguity is discussed in the Criticism section, moreover, orangutans are a sister group to Homininae and are the basal genus in the family as a whole. Subfamilies Homininae and Ponginae are both basal within Hominidae, but given that there are no subfamilies in the cladogram it is unlikely the term would be applied to either. In general, a statement to the effect that one group is basal, or branches off first, if that level cannot be specified a more detailed description of the relevant sister groups may be needed. In this example, orangutans differ from the genera in their Eurasian range. This fact plus their basal status provides a hint that the most recent common ancestor of extant great apes may have been Eurasian, despite the ubiquity of the usage of the term, some systematists believe its application to extant groups is unnecessary and misleading. This is because a pair of branches of a phylogenetic tree are equally ranked. The term tends to be applied when one branch is less diverse than another branch and this situation raises an equivocal usage for the term basal in that it also refers to the direction of the root of the tree
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Shark
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Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha and are the group to the rays. Under this broader definition, the earliest known sharks date back to more than 420 million years ago, acanthodians are often referred to as spiny sharks, though they are not part of Chondrichthyes proper, they are a paraphyletic assemblage leading to cartilaginous fish as a whole. Since then, sharks have diversified into over 500 species, Sharks are found in all seas and are common to depths of 2,000 metres. They generally do not live in freshwater although there are a few exceptions, such as the bull shark and the river shark. Sharks have a covering of dermal denticles that protects their skin from damage and they have numerous sets of replaceable teeth. Well-known species such as the white shark, tiger shark, blue shark, mako shark. Many shark populations are threatened by human activities, until the 16th century, sharks were known to mariners as sea dogs. The etymology of the shark is uncertain. One theory is that it derives from the Yucatec Maya word xok, however, the Middle English Dictionary records an isolated occurrence of the word shark in a letter written by Thomas Beckington in 1442, which rules out a New World etymology. Evidence for the existence of sharks dates from the Ordovician period, 450–420 million years ago, before land vertebrates existed and before many plants had colonized the continents. Only scales have been recovered from the first sharks and not all agree that these are from true sharks. The oldest generally accepted shark scales are from about 420 million years ago, the first sharks looked very different from modern sharks. The majority of sharks can be traced back to around 100 million years ago. Most fossils are of teeth, often in large numbers, partial skeletons and even complete fossilized remains have been discovered. Estimates suggest that sharks grow tens of thousands of teeth over a lifetime, the teeth consist of easily fossilized calcium phosphate, an apatite. When a shark dies, the decomposing skeleton breaks up, scattering the apatite prisms, preservation requires rapid burial in bottom sediments. Among the most ancient and primitive sharks is Cladoselache, from about 370 million years ago, which has been found within Paleozoic strata in Ohio, Kentucky, and Tennessee
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Coelacanth
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They follow the oldest known living lineage of Sarcopterygii, which means they are more closely related to lungfish, reptiles and mammals than to the common ray-finned fishes. They are found along the coastlines of the Indian Ocean and Indonesia, since there are only two species of coelacanth and both are threatened, it is the most endangered order of animals in the world. The West Indian Ocean coelacanth is a endangered species. Coelacanths belong to the subclass Actinistia, a group of lobed-finned fish related to lungfish and certain extinct Devonian fish such as osteolepiforms, porolepiforms, rhizodonts, and Panderichthys. Coelacanths were thought to have become extinct in the Late Cretaceous, around 66 million years ago, however, several recent studies have shown that coelacanth body shapes are much more diverse than previously thought. The word Coelacanth is an adaptation of the Modern Latin Cœlacanthus and it is a common name for the oldest living line of Sarcopterygii, referring to the hollow caudal fin rays of the first fossil specimen described and named by Louis Agassiz in 1839. The genus name Latimeria commemorates Marjorie Courtenay-Latimer who discovered the first specimen in a fish market, the coelacanth, which is related to lungfishes and tetrapods, was believed to have been extinct since the end of the Cretaceous period. More closely related to tetrapods than to the fish, coelacanths were considered transitional species between fish and tetrapods. On 23 December 1938, the first Latimeria specimen was found off the east coast of South Africa, Museum curator Marjorie Courtenay-Latimer discovered the fish among the catch of a local angler, Captain Hendrick Goosen. A Rhodes University ichthyologist, J. L. B, smith, confirmed the fishs importance with a famous cable, MOST IMPORTANT PRESERVE SKELETON AND GILLS = FISH DESCRIBED. Since 1938, Latimeria chalumnae have been found in the Comoros, Kenya, Tanzania, Mozambique, Madagascar, only a photograph of the first specimen of this species was made at a local market by Erdmann and his wife Arnaz Mehta before it was bought by a shopper. The coelacanth has no commercial value apart from being coveted by museums. As a food fish it is almost worthless, as its tissues exude oils that give the flesh a foul flavor, the coelacanths continued survival may be threatened by commercial deep-sea trawling, in which coelacanths are caught as bycatch. Coelacanths are a part of the clade Sarcopterygii, or the lobe-finned fishes, externally, several characteristics distinguish the coelacanth from other lobe-finned fish. They possess a three-lobed caudal fin, also called a fin or a diphycercal tail. A secondary tail extending past the tail separates the upper and lower halves of the coelacanth. Cosmoid scales act as armor to protect the coelacanths exterior. Several internal traits also aid in differentiating coelacanths from other lobe-finned fish, at the back of the skull, the coelacanth possesses a hinge, the intracranial joint, which allows it to open its mouth extremely wide
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Lungfish
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The Queensland lungfish, Neoceratodus forsteri, is a surviving member of the family Neoceratodontidae and order Ceratodontiformes. It is one of six extant lungfish species in the world. Endemic to Australia, the Neoceratodontidae are an ancient family belonging to the class Sarcopterygii, fossil records of this group date back 380 million years, around the time when the higher vertebrate classes were beginning to evolve. It is one of six extant representatives of the ancient air-breathing Dipnoi that flourished during the Devonian period and is the most primitive surviving member of this lineage. The five other freshwater species, four in Africa and one in South America, are very different morphologically from N. forsteri. The Queensland lungfish can live for days out of the water, if it is kept moist. The small settlement of Ceratodus, Queensland, derives its name from that of the Queensland lungfish, the Queensland lungfish is native only to the Mary and Burnett River systems in south-eastern Queensland. It has been distributed to other, more southerly rivers, including the Brisbane, Albert, Stanley, and Coomera Rivers. The Queensland lungfish has also introduced to the Pine, Caboolture, and Condamine Rivers. Formerly widespread, at one time at least seven species of lungfish were in Australia and this species lives in slow-flowing rivers and still water that have some aquatic vegetation present on banks. It occurs over mud, sand, or gravel bottoms, the lungfish is tolerant of cold, but prefers waters with temperatures between 15 and 25 °C. The Queensland lungfish is incapable of surviving complete desiccation of its habitat, unlike the African species, Protopterus, it does not survive dry seasons by secreting a mucous cocoon and burying itself in the mud. The Queensland lungfish is essentially a sedentary species, spending its life within a restricted area and its home range rarely extends beyond a single pool or, occasionally, two adjacent pools. It does not follow a set path, but may actively seek out suitable spawning habitats between July and December. Queensland lungfish are olive-green to dull brown on the back, sides, tail, and fins and they have been described as having a reddish colouring on their sides which gets much brighter in the males during the breeding season. This colouration is the only distinguishing sexual characteristic of the lungfish and they have stout, elongated bodies and flattened heads with small eyes. The mouth is small and in a subterminal position, the lungfish can grow to a length of about 150 cm, and a weight of 43 kg. It is commonly found to be about 100 cm and 20 kg on average, both sexes follow similar growth patterns, although the females grow to a slightly larger size
