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weathering
weathering collective term for the processes by which rock at or near the earth's surface is disintegrated and decomposed by the action of atmospheric agents, water, and living things. Some of these processes are mechanical, e.g., the expansion and contraction caused by sudden, large changes in temperature, the expansive force of water freezing in cracks, the splitting caused by plant roots, and the impact of running water; others are chemical, e.g., oxidation, hydration, carbonization, and loss of chemical elements by solution in water. Weathering is important because it aids in the formation of soil and prepares materials for erosion . Construction materials for buildings and roads are subject to weathering by water, carbon dioxide, aerosol gases, freeze-thaw cycles, and salt (see also formation of potholes ). New techniques in road construction, allowing a minimum of weathering, more weather-resistant aggregates, and better building materials have lowered costs for maintenance and repair. |
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Cite this article
"weathering." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "weathering." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-weatheri.html "weathering." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-weatheri.html |
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weathering
weathering The breakdown of rocks and minerals at and below the Earth's surface by the action of physical and chemical processes. Essentially it is the response of Earth materials to the low pressures, low temperatures, and presence of air and water that characterize the near-surface environment, but which were not typical of the environment of formation. There are several varieties of rock breakdown (see also MECHANICAL WEATHERING). Simple disintegration may occur, resulting in the production of coarse, angular blocks, of peels or skins (the process of ‘desquamation’), of sands, and of silts. Minerals may be removed in solution, and chemical weathering may form new, often easily eroded substances. See also CARBONATION; EROSION; FROST WEDGING; HYDRATION; HYDROLYSIS; and THERMOCLASTIS.
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Cite this article
AILSA ALLABY and MICHAEL ALLABY. "weathering." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "weathering." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-weathering.html AILSA ALLABY and MICHAEL ALLABY. "weathering." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-weathering.html |
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weathering
weathering The breakdown of rocks and minerals at and below the Earth's surface by the action of physical and chemical processes. Essentially it is the response of Earth materials to the low pressures, low temperatures, and presence of air and water that characterize the near-surface environment, but which were not typical of the environment of formation. There are several varieties of rock breakdown. Simple disintegration may occur, resulting in the production of coarse, angular blocks, of peels or skins (the process of ‘desquamation’), of sands, and of silts. Minerals may be removed in solution, and chemical weathering may form new, often easily eroded substances.
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Cite this article
MICHAEL ALLABY. "weathering." A Dictionary of Ecology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "weathering." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O14-weathering.html MICHAEL ALLABY. "weathering." A Dictionary of Ecology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-weathering.html |
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weathering
weathering Breakdown and chemical disintegration of rocks and minerals at the Earth's surface by physical and chemical processes. In physical weathering in cold, wet climates, water seeping into cracks in the rock expands on freezing, so causing the rock to crack further and to crumble. Extreme temperature changes in drier regions, such as deserts, also cause rocks to fragment. Chemical weathering can lead to a weakening of the rock structure by altering the minerals of a rock and changing their size, volume, and ability to hold shape. Unlike erosion, weathering does not involve transportation.
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"weathering." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "weathering." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-weathering.html "weathering." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-weathering.html |
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weathering
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Cite this article
JAMES STEVENS CURL. "weathering." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. JAMES STEVENS CURL. "weathering." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O1-weathering.html JAMES STEVENS CURL. "weathering." A Dictionary of Architecture and Landscape Architecture. 2000. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O1-weathering.html |
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