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Pennyroyal Plateau
The Pennyroyal Plateau or Pennyroyal Region, often spelled Pennyrile, is a large physiographic region of Kentucky that features rolling hills, caves, and karst topography in general. It is named for a wild mint that grows in the area. It is also called the "Mississippian Plateau," for the Mississippian geologic age in which it was formed. The Pennyroyal is bordered by the Pottsville Escarpment in the east. The Pottsville Escarpment is the transition zone from the central part of Kentucky to the higher and geologically younger Cumberland Plateau in the eastern part of the state. The Pennyroyal is bordered on the north by Muldraugh Hill, the geological escarpment that forms the transition from the geologically older Bluegrass to the Pennyroyal. This is a series of knobs and ridges based on hard siltstones. The Pennyroyal is bordered on the west by the younger Jackson Purchase. The Pennyroyal is often thought by non-geologists to include the West Kentucky Coal Field of Pennsy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jackson Purchase
The Jackson Purchase, also known as the Purchase Region or simply the Purchase, is a region in the U.S. state of Kentucky bounded by the Mississippi River to the west, the Ohio River to the north, and the Tennessee River to the east. Jackson's Purchase also included all of Tennessee west of the Tennessee River. However, in modern usage the term refers only to the Kentucky portion of the Jackson Purchase. The southern portion is simply called West Tennessee. Geography The Purchase comprised what is now eight counties, with a combined land area of 3,394.8 square miles (6,202.5 km²), about 6.03 percent of Kentucky's land area. Its 2010 census population was 196,365 inhabitants, equal to 4.53 percent of the state's population. Paducah, the largest city and main economic center, has just over 25,000 residents. The region's other two largest cities, Murray and Mayfield, have about 18,000 and 10,000 residents respectively. The main educational institution is Murray State Univer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regions Of Kentucky
Kentucky ( , ), officially the Commonwealth of Kentucky, is a state in the Southeastern region of the United States and one of the states of the Upper South. It borders Illinois, Indiana, and Ohio to the north; West Virginia and Virginia to the east; Tennessee to the south; and Missouri to the west. Its northern border is defined by the Ohio River. Its capital is Frankfort, and its two largest cities are Louisville and Lexington. Its population was approximately 4.5 million in 2020. Kentucky was admitted into the Union as the 15th state on June 1, 1792, splitting from Virginia in the process. It is known as the "Bluegrass State", a nickname based on Kentucky bluegrass, a species of green grass found in many of its pastures, which has supported the thoroughbred horse industry in the center of the state. Historically, it was known for excellent farming conditions for this reason and the development of large tobacco plantations akin to those in Virginia and North Carolina in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammoth Cave
Mammoth Cave National Park is an American national park in west-central Kentucky, encompassing portions of Mammoth Cave, the longest cave system known in the world. Since the 1972 unification of Mammoth Cave with the even-longer system under Flint Ridge to the north, the official name of the system has been the Mammoth–Flint Ridge Cave System. The park was established as a national park on July 1, 1941, a World Heritage Site on October 27, 1981, an international Biosphere Reserve on September 26, 1990 and an International Dark Sky Park on October 28, 2021. The park's are located primarily in Edmonson County, with small areas extending eastward into Hart and Barren counties. The Green River runs through the park, with a tributary called the Nolin River feeding into the Green just inside the park. Mammoth Cave is the world's longest known cave system with more than of surveyed passageways, which is nearly twice as long as the second-longest cave system, Mexico's ... [...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] |
Middle Tennessee
Middle Tennessee is one of the three Grand Divisions of the U.S. state of Tennessee that composes roughly the central portion of the state. It is delineated according to state law as 41 of the state's 95 counties. Middle Tennessee contains the state's capital and largest city, Nashville, as well as Clarksville, the state's fifth largest city, and Murfreesboro, the state's sixth largest city and largest suburb of Nashville. The Nashville metropolitan area, located entirely within the region, is the most populous metropolitan area in the state, and the Clarksville metropolitan area is the state's sixth most populous. Middle Tennessee is both the largest, in terms of land area, and the most populous of the state's three Grand Divisions. Geographically, Middle Tennessee is composed of the Highland Rim, which completely surrounds the Nashville Basin. The Cumberland Plateau is located in the eastern part of the region. Culturally, Middle Tennessee is considered part of the Upland Sout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Highland Rim
The Highland Rim is a geographic term for the area in Tennessee surrounding the Central Basin. Nashville is largely surrounded by higher terrain in all directions. Geologically, the Central Basin is a dome. The Highland Rim is a cuesta surrounding the basin, and the border where the difference in elevation is sharply pronounced is an escarpment. Nashville is located in the northwestern corner of the basin. Geology and Physiography The Highland Rim is a physiographic section of the larger Interior Low Plateaus province, which in turn is part of the larger Interior Plains physiographic division. Most of the Highland Rim is located in U.S. EPA Ecoregion 71, Interior Plateau, which is a part of the Eastern Temperate Forest. The sections of the Highland Rim are referred to the four cardinal directions, e.g., "Northern Highland Rim", etc. The Highland Rim is rather continuous and any division of it, including the ones made below, are somewhat arbitrary. The term "highland" here is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illinois Basin
The Illinois Basin is a Paleozoic depositional and structural basin in the United States, centered in and underlying most of the state of Illinois, and extending into southwestern Indiana and western Kentucky. The basin is elongate, extending approximately northwest-southeast, and southwest-northeast. Boundaries and sedimentary rocks The basin is bordered on the northeast by the Kankakee Arch, on the southeast by the Cincinnati Arch, on the south by the Pascola Arch, on the southwest by the Ozark Dome, on the northwest by the Mississippi River Arch, and on the north by the Wisconsin Arch. The New Madrid Seismic Zone and the Wabash Valley Seismic Zone intersect the southern portion of the basin. The major structural features within the basin include the La Salle anticlinal belt, the DuQuoin monocline, the Cottage Grove fault system, and the Fairfield Basin. At its center beneath southern Illinois, the basin contains a thickness of about 15,000 feet of Cambrian throug ... [...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] |
West Kentucky Coal Field
The West Kentucky Coal Field comprises an area in the west-central and northwestern part of the state, bounded by the Dripping Springs Escarpment and the Pennyroyal Plateau and the Ohio River, but is part of the Illinois Basin that extends into Indiana and Illinois. It is characterized by Pennsylvanian age sandstones, shales and coal. Nearly all of the counties in the area are part of the television market known as the Kentucky–Illinois–Indiana tri-state area. Included areas The Western Coal Field region of Kentucky includes all of the following counties: * Butler County * Daviess County * Hancock County * Henderson County * Hopkins County * McLean County *Muhlenberg County * Ohio County * Union County * Webster County Additionally, the region includes parts of the following counties, mostly in the Clifty Area, which does not contain coal: * Breckinridge County *Christian County * Edmonson County * Grayson County * Hart County *Logan County * Todd County *Warren County T ... [...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] |
Physiography
Physical geography (also known as physiography) is one of the three main branches of geography. Physical geography is the branch of natural science which deals with the processes and patterns in the natural environment such as the atmosphere, hydrosphere, biosphere, and geosphere. This focus is in contrast with the branch of human geography, which focuses on the built environment, and technical geography, which focuses on using, studying, and creating tools to obtain,analyze, interpret, and understand spatial information. The three branches have significant overlap, however. Sub-branches Physical geography can be divided into several branches or related fields, as follows: * Geomorphology is concerned with understanding the surface of the Earth and the processes by which it is shaped, both at the present as well as in the past. Geomorphology as a field has several sub-fields that deal with the specific landforms of various environments e.g. desert geomorphology and fluvial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
