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Allochthon
upright=1.6, Schematic overview of a thrust system. The hanging wall block is (when it has reasonable proportions) called a window. A klippe is a solitary outcrop of the nappe in the middle of autochthonous material. An allochthon, or an allochthonous block, is a large block of rock which has been moved from its original site of formation, usually by low angle thrust faulting. The term is derived from Greek: ''allo'', meaning other, and ''chthon'', meaning earth. For other possible mechanisms see obduction. An allochthon which is isolated from the rock that pushed it into position is called a klippe. If an allochthon has a "hole" in it so that one can view the autochthon beneath the allochthon, the hole is called a "window" (or fenster). In generalized terms, the term is applied to any geologic units that originated at a distance from their present location. In the United States there are three notable allochthons, all of which were displaced nearly 50 km (31 miles) along ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autochthon (geology)
An autochthon in structural geology is a large block or mass of rock which is in the place of its original formation relative to its Basement (geology), basement or foundation rock. The word is derived from Greek: ''autos'' means self, and ''chthon'' means earth. It can be described as rooted to its basement rock as opposed to an allochthonous block or nappe which has been relocated from its site of formation. Autochthonous sediment is sediment found at or very close to its site of deposition. image:thrust system en.jpg, upright=1.6, Schematic overview of a thrust system. The hanging wall block is (when it has reasonable proportions) called a nappe which overlays the autochthonous (unrelocated) material. A hole in the nappe which exposes the underlying autochthonous material is called a window (geology), window. A klippe is a solitary outcrop of the nappe in the middle of autochthonous material. While an autochthon may have experienced some minor shifting, an allochthonous block ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golconda Thrust
The Golconda Thrust is a major oceanic terrane that was thrust over central and northern Nevada, North America, in possibly sometime between the late Permian and the late Jurassic. It is considered equivalent to the Tobin thrust fault. It contains the Havallah sequence. Timing the Golconda Thrust The time of the Golconda Thrust is not perfectly clear, and it may pre-date the Sonoma orogeny. Other references suspect it appears to have thrust during the Sonoma orogeny. See also * Geology of Nevada * Golconda, Nevada Golconda is a census-designated place in southeastern Humboldt County, Nevada, United States. As of the 2020 census it has a population of 182. It is located along Interstate 80 on the Humboldt River in the northwestern part of the state. Golco ... * Sonomia terrane References External links and references One link Geology of Nevada Terranes {{US-geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust System En
Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that system. The force applied on a surface in a direction perpendicular or normal to the surface is also called thrust. Force, and thus thrust, is measured using the International System of Units (SI) in newtons (symbol: N), and represents the amount needed to accelerate 1 kilogram of mass at the rate of 1 meter per second per second. In mechanical engineering, force orthogonal to the main load (such as in parallel helical gears) is referred to as static thrust. Examples A fixed-wing aircraft propulsion system generates forward thrust when air is pushed in the direction opposite to flight. This can be done by different means such as the spinning blades of a propeller, the propelling jet of a jet engine, or by ejecting hot gases from a rocke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust Fault
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. If the angle of the fault plane is lower (often less than 15 degrees from the horizontal) and the displacement of the overlying block is large (often in the kilometer range) the fault is called an ''overthrust'' or ''overthrust fault''. Erosion can remove part of the overlying block, creating a ''fenster'' (or ''window'') – when the underlying block is exposed only in a relatively small area. When erosion removes most of the overlying block, leaving island-like remnants resting on the lower block, the remnants are called ''klippen'' (singular '' klippe''). Blind thrust faults If the fault plane terminates before it reaches the Earth's surface, it is called a ''blind thrust'' fault. Because of the lack of surface evidence, blind thrust fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Obduction
Obduction is a geological process whereby denser oceanic crust (and even upper mantle) is scraped off a descending ocean plate at a convergent plate boundary and thrust on top of an adjacent plate. When oceanic and continental plates converge, normally the denser oceanic crust sinks under the continental crust in the process of subduction. Obduction, which is less common, normally occurs in plate collisions at orogenic belts (some of the material from the subducting oceanic plate is emplaced onto the continental plate)Dewey, J. F., 1975. The role of ophiolite obduction in the evolution of the Appalachian/Caledonian orogenic belt. In: N. Bogdanov (editor), Ophiolites in the Earth’s Crust. Acad. Sci. U.S.S.R. (in press) or back-arc basins (regions where the edge of a continent is pulled away from the rest of the continent due to the stress of plate collision). Obduction of oceanic lithosphere produces a characteristic set of rock types called an ophiolite. This assemblage consi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klippe
350px, Schematic overview of a thrust system. The shaded material is called a window or fenster. The klippe is the isolated block of the nappe overlying autochthonous material. A klippe ( German for cliff">German language">German for cliff or crag; plural klippen or ''klippes'') is a geological feature of thrust fault terrains. The klippe is the remnant portion of a nappe after erosion has removed connecting portions of the nappe. This process results in an outlier of exotic, often nearly horizontally translated strata overlying autochthonous strata. Examples * Chief Mountain, Montana *Mount Yamnuska, Alberta *The Rock of Gibraltar *Acropolis of Athens, Greece * Bac Grillera, Catalonia, Spain. The nappe of which this klippe once formed part had its root in the northern part of the Pyrenees mountain range. Klippes may also be found in the Pre-Alps of Switzerland and some of the isolated mountains in Assynt, Sutherland, in NW Scotland.Whittow, John (1984). ''Dictionary of Ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Window (geology)
350px, Schematic overview of a thrust system. The hanging wall block is (when it has reasonable proportions) called a erosion.html" ;"title="nappe. If an erosion">nappe. If an erosional hole is created in the nappe that is called a window. A klippe is a solitary outcrop of the nappe in the middle of autochthonous material. A tectonics, tectonic window, or fenster (lit. "window" in German language, German), is a geology, geologic structure formed by erosion or normal faulting on a thrust fault, thrust system. In such a system the rock mass ( fault (geology), hanging wall block) that has been transported by movement along the thrust is called a nappe. When erosion or normal faulting produces a hole in the nappe where the underlying autochthonous (i.e. un-transported) rocks crop out this is called a window. Klippen are also a feature near windows. The klippe is the remnant portion of a nappe after erosion has removed connecting portions of the nappe. This process results in an out ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nevada
Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, the 32nd-most populous, and the ninth-least densely populated U.S. state. Nearly three-quarters of Nevada's population live in Clark County, which contains the Las Vegas–Paradise metropolitan area, including three of the state's four largest incorporated cities. Nevada's capital is Carson City. Las Vegas is the largest city in the state. 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 (the words "Battle Born" also appear on its state flag); due to the presidency of Abraham Lincoln, the Union benefited immensely from the support of newly awarded statehood by the infusion of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New York (state)
New York, also called New York State, is a U.S. state, state in the northeastern United States. Bordered by New England to the east, Canada to the north, and Pennsylvania and New Jersey to the south, its territory extends into both the Atlantic Ocean and the Great Lakes. New York is the List of U.S. states and territories by population, fourth-most populous state in the United States, with nearly 20 million residents, and the List of U.S. states and territories by area, 27th-largest state by area, with a total area of . New York has Geography of New York (state), a varied geography. The southeastern part of the state, known as Downstate New York, Downstate, encompasses New York City, the List of U.S. cities by population, most populous city in the United States; Long Island, with approximately 40% of the state's population, the nation's most populous island; and the cities, suburbs, and wealthy enclaves of the lower Hudson Valley. These areas are the center of the expansive New ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Massachusetts
Massachusetts ( ; ), officially the Commonwealth of Massachusetts, is a U.S. state, state in the New England region of the Northeastern United States. It borders the Atlantic Ocean and the Gulf of Maine to its east, Connecticut and Rhode Island to its south, New Hampshire and Vermont to its north, and New York (state), New York to its west. Massachusetts is the List of U.S. states and territories by area, sixth-smallest state by land area. With a 2024 U.S. Census Bureau-estimated population of 7,136,171, its highest estimated count ever, Massachusetts is the most populous state in New England, the List of U.S. states and territories by population, 16th-most-populous in the United States, and the List of states and territories of the United States by population density, third-most densely populated U.S. state, after New Jersey and Rhode Island. Massachusetts was a site of early British colonization of the Americas, English colonization. The Plymouth Colony was founded in 16 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermont
Vermont () is a U.S. state, state in the New England region of the Northeastern United States. It borders Massachusetts to the south, New Hampshire to the east, New York (state), New York to the west, and the Provinces and territories of Canada, Canadian province of Quebec to the north. According to the most recent U.S. Census estimates, the state has an estimated population of 648,493, making it the List of U.S. states and territories by population, second-least populated of all U.S. states. It is the nation's List of U.S. states and territories by area, sixth smallest state in area. The state's capital of Montpelier, Vermont, Montpelier is the least populous List of capitals in the United States, U.S. state capital. No other U.S. state has a List of largest cities of U.S. states and territories by population, most populous city with fewer residents than Burlington, Vermont, Burlington. Native Americans in the United States, Native Americans have inhabited the area for abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laurentia
Laurentia or the North American craton is a large continental craton that forms the Geology of North America, ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of North America, although originally it also included the cratonic areas of Greenland and the Hebridean terrane in northwest Scotland. During other times in its past, Laurentia has been part of larger continents and supercontinents and consists of many smaller terranes assembled on a network of early Proterozoic Orogenic belt, orogenic belts. Small microcontinents and oceanic islands collided with and Suture (geology), sutured onto the ever-growing Laurentia, and together formed the stable Precambrian craton seen today. Etymology The craton is named after the Laurentian Shield, through the Laurentian Mountains, which received their name from the St. Lawrence River, named after Saint Lawrence of Rome. Interior platform In eastern and centra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
