landform

landform
/land"fawrm'/, n. Geol.
a specific geomorphic feature on the surface of the earth, ranging from large-scale features such as plains, plateaus, and mountains to minor features such as hills, valleys, and alluvial fans.
[1890-95; LAND + FORM]

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 any conspicuous topographic feature on the Earth or a similar planetary body or satellite. Familiar examples are mountains (including volcanic cones), plateaus, and valleys. Comparable structures have been detected on Mars, Venus, the Moon, and certain satellites of Jupiter and Saturn. The term landform also can be applied to related features that occur on the floor of the Earth's ocean basins, as, for example, seamounts, mid-oceanic ridges, and submarine canyons.

      A brief treatment of landforms follows. For full treatment of those on the Earth, see continental landform. For coverage of the topographic features of the so-called terrestrial planets and of various major satellites, see solar system.

      The distribution and structure of landforms reflect the geomorphic processes that created them. Most landforms occurring at the surface of the terrestrial land masses result from the interaction of two fundamental types of processes over geologic time. These are (1) vertical tectonic (tectonics) movements and extrusion of magma (molten rock material) and (2) denudational processes, which encompass the weathering and erosion of rocks and the accumulation of the resulting sedimentary debris.

      Relief features produced chiefly by uplift and subsidence of the Earth's crust or by upward magmatic movements can be classified as tectonic landforms. They include rift valleys, plateaus, mountains, and volcanic cones. Other topographic features, such as pediments, sand dunes, subterranean caves, fjords, and beaches, are formed by denudational processes. These features, categorized as structural landforms, are attributable to the erosional and depositional action of rivers, wind, groundwater solution, glaciers, sea waves, and other external agents.

 Although tectonic and denudational processes account for the origin of most landform types, a few have been produced by other means. Impact craters, for one, are formed by collisions with asteroids, comets, and meteorites. Biogenic landforms, for another, are produced—as the term implies—by living organisms. They range from giant termite mounds and coral reefs to open-pit mines and dams created by humans.
 

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Universalium. 2010.

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  • landform —    Any physical, recognizable form or feature on the earth s surface, having a characteristic shape, internal composition, and produced by natural causes; a distinct individual produced by a set of processes. Landforms can span a large size (e.g …   Glossary of landform and geologic terms

  • landform — (n.) 1893; see LAND (Cf. land) (n.) + FORM (Cf. form) (n.). Perhaps immediately from Ger. Landform …   Etymology dictionary

  • landform — ► NOUN ▪ a natural feature of the earth s surface …   English terms dictionary

  • landform — [land′fôrm΄] n. any topographic feature on the earth s surface, as a plain, valley, hill, etc., caused by erosion, sedimentation, or movement …   English World dictionary

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  • landform — UK [ˈlæn(d)ˌfɔː(r)m] / US [ˈlændˌfɔrm] noun [countable] Word forms landform : singular landform plural landforms a feature on the Earth s surface such as a mountain or a valley …   English dictionary

  • landform — [[t]læ̱ndfɔrm[/t]] landforms also land form N COUNT A landform is any natural feature of the Earth s surface, such as a hill, a lake, or a beach. This small country has an amazing variety of landforms. ...glacial land forms …   English dictionary

  • landform — noun Date: 1893 a natural feature of a land surface …   New Collegiate Dictionary

  • Landform — Als Landformen oder Geländeform (auch Geländeformation, Erdform) werden in den Geowissenschaften die typischen Ausprägungen der regionalen Landschaft und des lokalen Geländes bezeichnet, wie sie je nach geologischen und geophysikalischen… …   Deutsch Wikipedia

  • landform — noun /ˈlænd.fɔːm,ˈlænd.fɔɹm/ Any geological feature, such as a mountain or valley …   Wiktionary

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