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Ice Wedge
An ice wedge is a crack in the ground formed by a narrow or thin piece of ice that measures up to 3–4 meters in length at ground level and extends downwards into the ground up to several meters. During the winter months, the water in the ground freezes and expands. Once temperatures reach −17 degrees Celsius or lower, the ice that has already formed acts like a solid and expands to form cracks in the surface known as ice wedges. As this process continues over many years ice wedges can grow, up to the size of a swimming pool. Ice wedges usually appear in a polygonal pattern known as ice wedge Polygon, polygons. The cracks can also be filled with materials other than ice, especially sand, and are then called sand wedges. Formation There are many theories that attempt to explain the origin of ice wedges but only one has been consistently supported by most prominent scientists: the thermal contraction theory. Thermal contraction theory The thermal contraction theory posits th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ice Wedge Iceland
Ice is water that is freezing, frozen into a solid state, typically forming at or below temperatures of 0 °Celsius, C, 32 °Fahrenheit, F, or 273.15 Kelvin, K. It occurs naturally on Earth, on other planets, in Oort cloud objects, and as interstellar ice. As a naturally occurring crystalline inorganic solid with an ordered structure, ice is considered to be a mineral. Depending on the presence of Impurity, impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less Opacity (optics), opaque bluish-white color. Virtually all of the ice on Earth is of a Hexagonal crystal system, hexagonal Crystal structure, crystalline structure denoted as ''ice Ih'' (spoken as "ice one h"). Depending on temperature and pressure, at least nineteen phases of ice, phases (Sphere packing, packing geometries) can exist. The most common phase transition to ice Ih occurs when liquid water is cooled below (, ) at standard atmospheric pressure. When water is coo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Mackenzie Delta Ice-Wedge Tuktoyaktuk Pingo (2)
Mackenzie, Mckenzie, MacKenzie, or McKenzie may refer to: People * Mackenzie (given name), a given name (including a list of people with the name) * Mackenzie (surname), a surname (including a list of people with the name) * Clan Mackenzie, a Scottish clan Places Cities, towns and roads Australia * Mackenzie, Queensland, a suburb of Brisbane * Mackenzie, Queensland (Central Highlands), a locality in the Central Highlands Region * Lake McKenzie, a perched lake in Queensland Canada * Mackenzie (provincial electoral district), a former constituency in British Columbia * Mackenzie, British Columbia, near Williston Lake in east central British Columbia * Mackenzie, Ontario, on Thunder Bay in west central Ontario * Mackenzie Mountains, a mountain range in northern Canada * District of Mackenzie, a former administrative district of Canada's Northwest Territories ''Alberta'' * Mackenzie County, a specialized municipality in northwestern Alberta * Mackenzie Highway, in Albert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Melting Pingo Wedge Ice
Melting, or Enthalpy of fusion, fusion, is a physical process that results in the phase transition of a chemical substance, substance from a solid to a liquid. This occurs when the internal energy of the solid increases, typically by the application of heat or Divorce, pressure, which increases the substance's temperature to the melting point. At the melting point, the ordering of ions or molecules in the solid breaks down to a less ordered state, and the solid melts to become a liquid. Substances in the molten state generally have reduced viscosity as the temperature increases. An exception to this principle is Allotropes of sulfur, elemental sulfur, whose viscosity increases in the range of 130 °C to 190 °C due to polymerization. Some organic compounds melt through mesophases, states of partial order between solid and liquid. First order phase transition From a thermodynamics point of view, at the melting point the change in Gibbs free energy ''∆G'' of the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ice Wedge
An ice wedge is a crack in the ground formed by a narrow or thin piece of ice that measures up to 3–4 meters in length at ground level and extends downwards into the ground up to several meters. During the winter months, the water in the ground freezes and expands. Once temperatures reach −17 degrees Celsius or lower, the ice that has already formed acts like a solid and expands to form cracks in the surface known as ice wedges. As this process continues over many years ice wedges can grow, up to the size of a swimming pool. Ice wedges usually appear in a polygonal pattern known as ice wedge Polygon, polygons. The cracks can also be filled with materials other than ice, especially sand, and are then called sand wedges. Formation There are many theories that attempt to explain the origin of ice wedges but only one has been consistently supported by most prominent scientists: the thermal contraction theory. Thermal contraction theory The thermal contraction theory posits th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Swimming Pool
A swimming pool, swimming bath, wading pool, paddling pool, or simply pool, is a structure designed to hold water to enable Human swimming, swimming and associated activities. Pools can be built into the ground (in-ground pools) or built above ground (as a freestanding construction or as part of a building or other larger structure), and may be found as a feature aboard ships. In-ground pools are most commonly constructed from materials such as concrete, natural stone, metal, plastic, composite or fiberglass, and may follow a standardized size, the largest of which is the Olympic-size swimming pool, or be of a custom shape. Many health clubs, fitness centers, and private clubs have pools for their members, often used for exercise. In much of the world, local governments provide publicly-run pools for their citizens. Many of these are outdoors; indoor pools are typically part of a leisure centre. Many hotels have a pool for the use of their guests. Pools as a feature in hotels ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Polygon
In geometry, a polygon () is a plane figure made up of line segments connected to form a closed polygonal chain. The segments of a closed polygonal chain are called its '' edges'' or ''sides''. The points where two edges meet are the polygon's '' vertices'' or ''corners''. An ''n''-gon is a polygon with ''n'' sides; for example, a triangle is a 3-gon. A simple polygon is one which does not intersect itself. More precisely, the only allowed intersections among the line segments that make up the polygon are the shared endpoints of consecutive segments in the polygonal chain. A simple polygon is the boundary of a region of the plane that is called a ''solid polygon''. The interior of a solid polygon is its ''body'', also known as a ''polygonal region'' or ''polygonal area''. In contexts where one is concerned only with simple and solid polygons, a ''polygon'' may refer only to a simple polygon or to a solid polygon. A polygonal chain may cross over itself, creating star polyg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Permafrost
Permafrost () is soil or underwater sediment which continuously remains below for two years or more; the oldest permafrost has been continuously frozen for around 700,000 years. Whilst the shallowest permafrost has a vertical extent of below a meter (3 ft), the deepest is greater than . Similarly, the area of individual permafrost zones may be limited to narrow mountain summits or extend across vast Arctic regions. The ground beneath glaciers and ice sheets is not usually defined as permafrost, so on land, permafrost is generally located beneath a so-called active layer of soil which freezes and thaws depending on the season. Around 15% of the Northern Hemisphere or 11% of the global surface is underlain by permafrost, covering a total area of around . This includes large areas of Alaska, Canada, Greenland, and Siberia. It is also located in high mountain regions, with the Tibetan Plateau being a prominent example. Only a minority of permafrost exists in the Southern Hemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Horizontal Compression
Horizontal may refer to: *Horizontal plane, in astronomy, geography, geometry and other sciences and contexts *Horizontal coordinate system, in astronomy *Horizontalism, in monetary circuit theory *Horizontalism, in sociology *Horizontal market, in microeconomics * ''Horizontal'' (album), a 1968 album by the Bee Gees ** "Horizontal" (song)" is a 1968 song by the Bee Gees See also *Horizontal and vertical *Horizontal and vertical (other) *Horizontal fissure (other), anatomical features *Horizontal bar The horizontal bar, also known as the high bar, is an apparatus used by male gymnasts in artistic gymnastics. It traditionally consists of a cylindrical metal (typically steel) bar that is rigidly held above and parallel to the floor by a syst ..., an apparatus used by male gymnasts in artistic gymnastics * Vertical (other) * {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Wedge
A wedge is a triangle, triangular shaped tool, a portable inclined plane, and one of the six simple machines. It can be used to separate two objects or portions of an object, lift up an object, or hold an object in place. It functions by converting a force applied to its blunt end into forces perpendicular (Surface normal, normal) to its inclined surfaces. The mechanical advantage of a wedge is given by the ratio of the length of its slope to its width..''McGraw-Hill Concise Encyclopedia of Science & Technology'', Third Ed., Sybil P. Parker, ed., McGraw-Hill, Inc., 1992, p. 2041. Although a short wedge with a wide angle may do a job faster, it requires more force than a long wedge with a narrow angle. The force is applied on a flat, broad surface. This energy is transported to the pointy, sharp end of the wedge, hence the force is transported. The wedge simply transports energy in the form of friction and collects it to the pointy end, consequently breaking the item. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Sediment
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension (chemistry), suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial, fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and stream channel, river channel deposits are examples of fluvial transport and deposition (geology), deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dirt
Dirt is any matter considered unclean, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debris: scattered pieces of waste or remains * Dust: a general powder of organic or mineral matter * Filth: foul matter such as excrement * Grime: a black, ingrained dust such as soot * Soil: the mix of clay, sand, and humus which lies on top of bedrock. The term 'soil' may be used to refer to unwanted substances or dirt that are deposited onto surfaces such as clothing. Etymology The word ''dirt'' first appears in Middle English and was probably borrowed from the Old Norse , meaning . Exhibitions and studies A season of artworks and exhibits on the theme of dirt was sponsored by the Wellcome Trust in 2011. The centrepiece was an exhibition at the Wellcome Collection showing pictures and histories of notable dirt such as the great dust heaps at Euston and King's Cross in the 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
