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
