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St. Paul, Arkansas
St. Paul is a town in Madison County, Arkansas, United States. The population was 111 at the 2020 census. It is on the edge of the Northwest Arkansas region. St. Paul was platted in 1887 when the railroad was extended to that point. Geography St. Paul is located in southern Madison County. Arkansas Highways 16 and 23 run through the town together as 5th Street and Madison Avenue. Highway 23 leads north to Huntsville, the county seat, and south to Ozark, while Highway 16 leads northwest to Fayetteville and east along the spine of the Boston Mountains to Clinton. According to the United States Census Bureau, the town has a total area of , of which , or 0.22%, are water. The community is located along the upper reaches of the White River. The north boundary of the Ozark-St. Francis National Forest is adjacent to the south side of the community. Ecoregion St. Paul is located in the Upper Boston Mountains ecoregion. The ecoregion is generally higher and moister than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Town
A town is a human settlement. Towns are generally larger than villages and smaller than cities, though the criteria to distinguish between them vary considerably in different parts of the world. Origin and use The word "town" shares an origin with the German word , the Dutch word , and the Old Norse . The original Proto-Germanic word, *''tūnan'', is thought to be an early borrowing from Proto-Celtic *''dūnom'' (cf. Old Irish , Welsh ). The original sense of the word in both Germanic and Celtic was that of a fortress or an enclosure. Cognates of ''town'' in many modern Germanic languages designate a fence or a hedge. In English and Dutch, the meaning of the word took on the sense of the space which these fences enclosed, and through which a track must run. In England, a town was a small community that could not afford or was not allowed to build walls or other larger fortifications, and built a palisade or stockade instead. In the Netherlands, this space was a garden, mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fayetteville, Arkansas
Fayetteville () is the second-largest city in Arkansas, the county seat of Washington County, and the biggest city in Northwest Arkansas. The city is on the outskirts of the Boston Mountains, deep within the Ozarks. Known as Washington until 1829, the city was named after Fayetteville, Tennessee, from which many of the settlers had come. It was incorporated on November 3, 1836, and was rechartered in 1867. The three-county Northwest Arkansas Metropolitan Statistical Area is ranked 102nd in terms of population in the United States with 560,709 in 2021 according to the United States Census Bureau. The city had a population of 95,230 in 2021. Fayetteville is home to the University of Arkansas, the state's flagship university. When classes are in session, thousands of students on campus change up the pace of the city. Thousands of Arkansas Razorbacks alumni and fans travel to Fayetteville to attend football, basketball, and baseball games. The city of Fayetteville is collo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolomite (rock)
Dolomite (also known as dolomite rock, dolostone or dolomitic rock) is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite, CaMg(CO3)2. It occurs widely, often in association with limestone and evaporites, though it is less abundant than limestone and rare in Cenozoic rock beds (beds less than about 66 million years in age). The first geologist to distinguish dolomite rock from limestone was Belsazar Hacquet in 1778. Most dolomite was formed as a magnesium replacement of limestone or of lime mud before lithification. The geological process of conversion of calcite to dolomite is known as dolomitization and any intermediate product is known as dolomitic limestone. The "dolomite problem" refers to the vast worldwide depositions of dolomite in the past geologic record in contrast to the limited amounts of dolomite formed in modern times. Recent research has revealed sulfate-reducing bacteria living in anoxic conditions precipitate dolomite which ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for limes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siltstone
Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, pp.381-382 Although its permeability and porosity is relatively low, siltstone is sometimes a tight gas reservoir rock, an unconventional reservoir for natural gas that requires hydraulic fracturing for economic gas production. Siltstone was prized in ancient Egypt for manufacturing statuary and cosmetic palettes. The siltstone quarried at Wadi Hammamat was a hard, fine-grained siltstone that resisted flaking and was almost ideal for such uses. Description There is not complete agreement on the definition of siltstone. One definition is that siltstone is mudrock ( clastic sedimentary rock containing at least 50% clay and silt) in which at least 2/3 of the clay and silt fraction is composed of silt-sized particles. Silt is defined a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.Blatt, Harvey and Robert J. Tracy (1996) ''Petrology: Igneous, Sedimentary and Metamorphic'', 2nd ed., Freeman, pp. 281–292 Shale is characterized by its tendency to split into thin layers ( laminae) less than one centimeter in thickness. This property is called '' fissility''. Shale is the most common sedimentary rock. The term ''shale'' is sometimes applied more broadly, as essentially a synonym for mudrock, rather than in the more narrow sense of clay-rich fissile mudrock. Texture Shale typically exhibits varying degrees of fissility. Because of the parallel orientation of clay mineral flakes in shale, it breaks into thin layers, often splintery and usually parallel to the otherwise indistinguishable beddin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, 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, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pennsylvanian (geology)
The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timescale, the younger of two period (geology), subperiods (or upper of two system (stratigraphy), subsystems) of the Carboniferous Period. It lasted from roughly . As with most other geochronology, geochronologic units, the stratum, rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain by a few hundred thousand years. The Pennsylvanian is named after the U.S. state of Pennsylvania, where the coal-productive beds of this age are widespread. The division between Pennsylvanian and Mississippian (geology), Mississippian comes from North American stratigraphy. In North America, where the early Carboniferous beds are primarily marine limestones, the Pennsylvanian was in the past treated as a full-fledged geologic period between the Mississippian and the Permian. In parts of Europe, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesic Habitat
In ecology, a mesic habitat is a type of habitat with a moderate or well-balanced supply of moisture, e.g., a mesic forest, a temperate hardwood forest, or dry-mesic prairie. Mesic habitats transition to xeric shrublands in a non-linear fashion, which is evidence of a threshold. Mesic is one of a triad of terms used to describe the amount of water in a habitat. The others are xeric and hydric. Further examples of mesic habitats include streamsides, wet meadows, springs, seeps, irrigated fields, and high elevation habitats. These habitats effectively provide drought insurance as land at higher elevations warms due to seasonal or other change. Healthy mesic habitats act like sponges in that they store water in such a way that it can be deposited to neighboring habitats as needed. They are common in dryer regions of the western United States, and can be a good water source to neighboring desert habitats. Healthy mesic habitats also provide forb and insects for organisms belonging t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oak–hickory Forest
Oak–hickory forest is a type of North American forest ecosystem, and an ecoregion of the Temperate broadleaf and mixed forests Biome. Geography It has a range extending from Rhode Island and southern New York, west to Iowa, and south to Northern Georgia. Smaller, isolated oak–hickory communities can also be found as far west as North Dakota, south in Florida and in northeast Texas, and north to southern Maine and Ontario. They can also be found in Pennsylvania west to Illinois. Dominated by nut-bearing oak and hickory species of trees, the oak–hickory forest has the largest range of any deciduous forest ecosystem in eastern and central North America. Natural history The current oak–hickory forest includes the former range of the oak–chestnut forest region, which encompassed the northeast portion of the current oak–hickory range. When the American chestnut population succumbed to invasive fungal blight in the early 20th century, those forests shifted to an oak and hicko ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White River (Arkansas–Missouri)
The White River is a river that flows through the U.S. states of Arkansas and Missouri. Originating in the Boston Mountains of northwest Arkansas, it arcs northwards through southern Missouri before turning back into Arkansas, flowing southeast to its mouth at the Mississippi River. Hydrography Course The source of the White River is in the Boston Mountains of northwest Arkansas, in the Ozark–St. Francis National Forest southeast of Fayetteville. The river flows northwards from its source to loop through southwest Missouri before heading southeast through Arkansas to its mouth on the Mississippi River. On entering the Mississippi River Valley region near Batesville, Arkansas, the river becomes navigable to shallow-draft vessels, and its speed decreases considerably. The final serves as the last segment of the McClellan-Kerr Arkansas River Navigation System; this part of the channel is deeper than the rest of the river. Discharge Despite being much shorter than th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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