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Alleghenian Orogeny
The Alleghanian orogeny or Appalachian orogeny is one of the geological mountain-forming events that formed the Appalachian Mountains and Allegheny Mountains. The term and spelling Alleghany orogeny was originally proposed by H.P. Woodward in 1957. The Alleghanian orogeny occurred approximately 325 million to 260 million years ago over at least five deformation events in the Carboniferous to Permian period. The orogeny was caused by Africa's collision with North America. At the time, these continents did not exist in their current forms: North America was part of the Euramerica super-continent, while Africa was part of Gondwana. This collision formed the super-continent Pangaea, which contained all major continental land masses. The collision provoked the orogeny: it exerted massive stress on what is today the Eastern Seaboard of North America, forming a wide and high mountain chain. Evidence for the Alleghanian orogeny stretches for many hundreds of miles on the surface from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hercynides EN
The Variscan or Hercynian orogeny was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea. Nomenclature The name ''Variscan'', comes from the Medieval Latin name for the district '' Variscia'', the home of a Germanic tribe, the Varisci; Eduard Suess, professor of geology at the University of Vienna, coined the term in 1880. (Variscite, a rare green mineral first discovered in the Vogtland district of Saxony in Germany, which is in the Variscan belt, has the same etymology.) ''Hercynian'', on the other hand, derives from the Hercynian Forest. Both words were descriptive terms of strike directions observed by geologists in the field, ''variscan'' for southwest to northeast, ''hercynian'' for northwest to southeast. The ''variscan'' direction reflected the direction of ancient fold belts cropping out throughout Germany and adjacent countries and the meaning shifted from d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alps
The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Switzerland, Italy, Liechtenstein, Austria, Germany, and Slovenia. The Alpine arch generally extends from Nice on the western Mediterranean to Trieste on the Adriatic and Vienna at the beginning of the Pannonian Basin. The mountains were formed over tens of millions of years as the African and Eurasian tectonic plates collided. Extreme shortening caused by the event resulted in marine sedimentary rocks rising by thrusting and folding into high mountain peaks such as Mont Blanc and the Matterhorn. Mont Blanc spans the French–Italian border, and at is the highest mountain in the Alps. The Alpine region area contains 128 peaks higher than . The altitude and size of the range affect the climate in Europe; in the mountains, precipitation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West Virginia
West Virginia is a state in the Appalachian, Mid-Atlantic and Southeastern regions of the United States.The Census Bureau and the Association of American Geographers classify West Virginia as part of the Southern United States while the Bureau of Labor Statistics classifies the state as a part of the Mid-Atlantic regionMid-Atlantic Home : Mid-Atlantic Information Office: U.S. Bureau of Labor Statistics" www.bls.gov. Archived. It is bordered by Pennsylvania to the north and east, Maryland to the east and northeast, Virginia to the southeast, Kentucky to the southwest, and Ohio to the northwest. West Virginia is the 10th-smallest state by area and ranks as the 12th-least populous state, with a population of 1,793,716 residents. The capital and largest city is Charleston. West Virginia was admitted to the Union on June 20, 1863, and was a key border state during the American Civil War. It was the only state to form by separating from a Confederate state, the second to sepa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virginia
Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth are shaped by the Blue Ridge Mountains and the Chesapeake Bay, which provide habitat for much of its flora and fauna. The capital of the Commonwealth is Richmond; Virginia Beach is the most-populous city, and Fairfax County is the most-populous political subdivision. The Commonwealth's population was over 8.65million, with 36% of them living in the Baltimore–Washington metropolitan area. The area's history begins with several indigenous groups, including the Powhatan. In 1607, the London Company established the Colony of Virginia as the first permanent English colony in the New World. Virginia's state nickname, the Old Dominion, is a reference to this status. Slave labor and land acquired from displaced native tribes fueled the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tennessee
Tennessee ( , ), officially the State of Tennessee, is a landlocked state in the Southeastern region of the United States. Tennessee is the 36th-largest by area and the 15th-most populous of the 50 states. It is bordered by Kentucky to the north, Virginia to the northeast, North Carolina to the east, Georgia, Alabama, and Mississippi to the south, Arkansas to the southwest, and Missouri to the northwest. Tennessee is geographically, culturally, and legally divided into three Grand Divisions of East, Middle, and West Tennessee. Nashville is the state's capital and largest city, and anchors its largest metropolitan area. Other major cities include Memphis, Knoxville, Chattanooga, and Clarksville. Tennessee's population as of the 2020 United States census is approximately 6.9 million. Tennessee is rooted in the Watauga Association, a 1772 frontier pact generally regarded as the first constitutional government west of the Appalachian Mountains. Its name derives from "Tanas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Carolina
North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and South Carolina to the south, and Tennessee to the west. In the 2020 census, the state had a population of 10,439,388. Raleigh is the state's capital and Charlotte is its largest city. The Charlotte metropolitan area, with a population of 2,595,027 in 2020, is the most-populous metropolitan area in North Carolina, the 21st-most populous in the United States, and the largest banking center in the nation after New York City. The Raleigh-Durham-Cary combined statistical area is the second-largest metropolitan area in the state and 32nd-most populous in the United States, with a population of 2,043,867 in 2020, and is home to the largest research park in the United States, Research Triangle Park. The earliest evidence of human occupation i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fold (geology)
In structural geology, a fold is a stack of originally planar surfaces, such as sedimentary strata, that are bent or curved during permanent deformation. Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur as single isolated folds or in periodic sets (known as ''fold trains''). Synsedimentary folds are those formed during sedimentary deposition. Folds form under varied conditions of stress, pore pressure, and temperature gradient, as evidenced by their presence in soft sediments, the full spectrum of metamorphic rocks, and even as primary flow structures in some igneous rocks. A set of folds distributed on a regional scale constitutes a fold belt, a common feature of orogenic zones. Folds are commonly formed by shortening of existing layers, but may also be formed as a result of displacement on a non-planar fault (''fault bend fold''), at the tip of a propagating fault (''fault propagation fold''), by differential compaction or due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Appalachian Basin
The geology of the Appalachians dates back to more than 480 million years ago. A look at rocks exposed in today's Appalachian Mountains reveals elongate belts of folded and thrust faulted marine sedimentary rocks, volcanic rocks and slivers of ancient ocean floor – strong evidence that these rocks were deformed during plate collision. The birth of the Appalachian ranges marks the first of several mountain building plate collisions that culminated in the construction of the supercontinent Pangaea with the Appalachians and neighboring Anti-Atlas mountains (now in Morocco) near the center. These mountain ranges likely once reached elevations similar to those of the Alps and the Rocky Mountains before they were eroded. Geological history Paleozoic Era During the earliest part of the Paleozoic Era, the continent that would later become North America straddled the equator. The Appalachian region was a passive plate margin, not unlike today's Atlantic Coastal Plain Provin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphic Rock
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition. The protolith may be an igneous, sedimentary, or existing metamorphic rock. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by their protolith, their chemical and mineral makeup, and their texture. They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction, and distorti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rock
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of geological detritus (minerals) or biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies (marine snow). Sedimentation may also occur as dissolved minerals precipitate from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Igneous Rock
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main The three types of rocks, rock types, the others being Sedimentary rock, sedimentary and metamorphic rock, metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava. The magma can be derived from Partial melting, partial melts of existing rocks in either a Terrestrial planet, planet's mantle (geology), mantle or crust (geology), crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive (geology), extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form Volcanic glass, natural glasses. Igneous rocks occur in a wide range of geological settings: shields, platforms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sahara
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