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replacement
replacement Widely used geologic term denoting a process that involves some kind of transformation. In a petrological sense it refers to the partial or complete alteration of an original mineral to an aggregate of secondary minerals, by the diffusion of ions between the solid phases and an introduced, fluid (usually water-rich) phase. Such diffusion takes place easily when the temperature of the rock system is below the stability limit of an individual mineral and a fluid is present to act as a catalyst to initiate the diffusion reactions. The secondary minerals may be all of one type, or a combination of mineral types. For example, high-temperature, magnesium-rich olivine can be replaced by an aggregate of secondary serpentine and chlorite, while plagioclase can be replaced by a fine aggregate of white mica (sericite). See also FOSSILIZATION.
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AILSA ALLABY and MICHAEL ALLABY. "replacement." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "replacement." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1O13-replacement.html AILSA ALLABY and MICHAEL ALLABY. "replacement." A Dictionary of Earth Sciences. 1999. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-replacement.html |
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replacement
re·place·ment / riˈplāsmənt/ • n. the action or process of replacing someone or something: the replacement of religion by poetry| a hip replacement. ∎ a person or thing that takes the place of another. |
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"replacement." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. "replacement." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1O999-replacement.html "replacement." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-replacement.html |
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replacement
replacement The substitution of one amino acid for another as a consequence of a nonsynonymous mutation at the DNA level.
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MICHAEL ALLABY. "replacement." A Dictionary of Ecology. 2004. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "replacement." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1O14-replacement.html MICHAEL ALLABY. "replacement." A Dictionary of Ecology. 2004. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-replacement.html |
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