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Horst And Graben
In geology, horst and graben (or range and valley) refers to topography consisting of alternating raised and lowered fault blocks known as horsts and grabens. The features are created by normal faulting and rifting caused by crustal extension. Horst and graben are formed when normal faults of opposite dip occur in pairs with parallel strike, and are always formed together. Each feature can range in size from a few centimeters up to tens of kilometers, and the vertical displacement can be up to several thousand meters. The movement on either side of each block is typically equal, resulting in little tilting. Features Horst A horst is a section of crust that has been lifted relative to the blocks on either side, which is a result of its bounding faults dipping away from each other. Horsts can form features such as plateaus, mountain ranges or ridges on either side of the valleys. Graben A graben is a section of crust that has lowered relative to the blocks on either ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tilted Block Faulting
Tilted block faulting, also called rotational block faulting, is a mode of structural evolution in extensional tectonic events, a result of tectonic plates stretching apart. When the upper lithospheric crust experiences extensional pressures, the brittle crust fractures, creating detachment faults. These normal faults express themselves on a regional scale; upper crust fractures into tilted fault blocks, and ductile lower crust ascends. This results in uplift, cooling, and exhumation of ductilely deformed deeper crust. The large unit of tilted blocks and associated crust can form an integral part of metamorphic core complexes, which are found on both continental and oceanic crust. Origin of term The term "tilted block faulting" is a literal description of rotational extension on planar faults, which results in a uniform rotation of faults and crust. Often a "domino-style" stacking of the fault blocks occurs, creating the basis of the terminology. Formation Faulting, tiltin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half-graben
A half-graben is a geological structure bounded by a fault along one side of its boundaries, unlike a full graben where a depressed block of land is bordered by parallel faults. Rift and fault structure A rift is a region where the lithosphere extends as two parts of the Earth's crust pull apart. Often a rift will form in an area of the crust that is already weakened by earlier geological activity. Extensional faults form parallel to the axis of the rift. An extensional fault may be seen as a crack in the crust that extends down at an angle to the vertical. As the two sides pull apart, the hanging wall ("hanging over" the sloping fault) will move downward relative to the footwall. The crust thins and sinks, forming a rift basin. Warm mantle material wells up, melting the crust and often causing volcanoes to emerge in the rift basin. Extensional basins may appear to be caused by a graben, or depressed block of land, sinking between parallel normal faults that dip towards th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rift (geology)
In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben with normal faulting and rift-flank uplifts mainly on one side. Where rifts remain above sea level they form a rift valley, which may be filled by water forming a rift lake. The axis of the rift area may contain volcanic rocks, and active volcanism is a part of many, but not all, active rift systems. Major rifts occur along the central axis of most mid-ocean ridges, where new oceanic crust and lithosphere is created along a divergent boundary between two tectonic plates. ''Failed rifts'' are the result of continental rifting that failed to continue to the point of break-up. Typically the transition from rifting to spreading develops at a triple junction where three converging rifts meet over a hotspot. Two of these evolve to the point ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tapti River
The Tapti River (or Tapi) is a river in central India located to the south of the Narmada river that flows westwards before draining into the Arabian Sea. The river has a length of around and flows through the states of Maharashtra, Gujarat and Madhya Pradesh. It flows through Surat, and is crossed by the Magdalla, ONGC Bridge. On 7 August 1968, before the construction of the Ukai Dam to bring its waters under control and provide hydroelectric power, the Tapti River overflowed its banks during heavy rains during the monsoon season. More than 1,000 people drowned in the flood, and the city of Surat was submerged beneath 10 feet of water for several days. After the floodwaters receded, at least 1,000 more people died in Gujarat during a cholera epidemic from the contamination of the drinking water. Its basin covers the parts of Madhya Pradesh, Gujarat and Maharashtra. Course The Tapti River rises in Multai, in Madhya Pradesh, and has a total length of around . It is the se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satpura Range
The Satpura Range is a range of hills in central India. The range rises in eastern Gujarat running east through the border of Maharashtra and Madhya Pradesh and ends in Chhattisgarh. The range parallels the Vindhya Range to the north, and these two east-west ranges divide Indian Subcontinent into the Indo-Gangetic plain of northern India and the Deccan Plateau of the south. The Narmada River originates from north-eastern end of Satpura in Amarkantak, and runs in the depression between the Satpura and Vindhya ranges, draining the northern slope of the Satpura range, running west towards the Arabian Sea. The Tapti River originates in the eastern-central part of Satpura, crossing the range in the center and running west at the range's southern slopes before meeting the Arabian Sea at Surat, draining the central and southern slopes of the range. Multai, the place of Tapi river origin is located about 465 kilometer far, south-westerly to Amarkantak, separated across by the hill range ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wallonia
Wallonia (; french: Wallonie ), or ; nl, Wallonië ; wa, Waloneye or officially the Walloon Region (french: link=no, Région wallonne),; nl, link=no, Waals gewest; wa, link=no, Redjon walone is one of the three regions of Belgium—along with Flanders and Brussels. Covering the southern portion of the country, Wallonia is primarily French-speaking. It accounts for 55% of Belgium's territory, but only a third of its population. The Walloon Region and the French Community of Belgium, which is the political entity responsible for matters related mainly to culture and education, are independent concepts, because the French Community of Belgium encompasses both Wallonia and the bilingual Brussels-Capital Region. There is a German-speaking minority in eastern Wallonia, resulting from the annexation of three cantons previously part of the German Empire at the conclusion of World War I. This community represents less than 1% of the Belgian population. It forms the German-speak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ardennes
The Ardennes (french: Ardenne ; nl, Ardennen ; german: Ardennen; wa, Årdene ; lb, Ardennen ), also known as the Ardennes Forest or Forest of Ardennes, is a region of extensive forests, rough terrain, rolling hills and ridges primarily in Belgium and Luxembourg, extending into Germany and France. Geologically, the range is a western extension of the Eifel; both were raised during the Givetian age of the Devonian (382.7 to 387.7 million years ago), as were several other named ranges of the same greater range. The Ardennes proper stretches well into Germany and France (lending its name to the Ardennes department and the former Champagne-Ardenne region) and geologically into the Eifel (the eastern extension of the Ardennes Forest into Bitburg-Prüm, Germany); most of it is in the southeast of Wallonia, the southern and more rural part of Belgium (away from the coastal plain but encompassing more than half of the country's total area). The eastern part of the Ardennes forms the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condroz
The Condroz () is a natural region in Wallonia (the French-speaking part of Belgium), located to the north-west of the Ardennes. Its unofficial capital is Ciney. The region preserves the name of the Condrusi, a Germanic tribe which inhabited the area in the Roman era. Compared to other parts of Belgium, the Condroz is a sparsely populated, agricultural area. It consists of low hills of an average altitude of about 200 to 300 meters (670–970 feet). It is mainly situated in the provinces of Liège and Namur and also in smaller parts of the Belgian provinces of Hainaut and Luxembourg. It is bordered in the north by the Meuse river, in the east by the Ardennes, in the south by the Famenne region. Historically, the Condroz did not stretch west of the Meuse, but today there is a western section, south of Namur and the Sambre river stretching to the Thiérache and southern Hainaut. History Very little is known of the Roman era Condrusi, after whom the region was originally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basin And Range Province
The Basin and Range Province is a vast physiographic region covering much of the inland Western United States and northwestern Mexico. It is defined by unique basin and range topography, characterized by abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins. The physiography of the province is the result of tectonic extension that began around 17 million years ago in the early Miocene epoch. The numerous ranges within the province in the United States are collectively referred to as the "Great Basin Ranges", although many are not actually in the Great Basin. Major ranges include the Snake Range, the Panamint Range, the White Mountains, and the Sandia Mountains. The highest point fully within the province is White Mountain Peak in California, while the lowest point is the Badwater Basin in Death Valley at . The province's climate is arid, with numerous ecoregions. Most North American deserts are located within it. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
