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stratigraphy
stratigraphy branch of geology specifically concerned with the arrangement of layered rocks (see stratification ). Stratigraphy is based on the law of superposition, which states that in a normal sequence of rock layers the youngest is on top and the oldest on the bottom. Local sequences are studied, and after considering such factors as the average rate of deposition of the different rocks, their composition, the width and extent of the strata, the fossils contained, and the periods of uplift and erosion, the geological history of the sequence is reconstructed. These sequences are then correlated to those of similar age in other regions with the ultimate aim of establishing a consistent geochronology for the entire earth. Statigraphy is therefore important in the relative dating of all types of rock. In areas where the strata have undergone folding, faulting, and erosion, stratigraphic techniques are used to determine their correct sequence. The principle of included fragments in stratigraphy states that any rock fragment included in another rock must be older than the surrounding rock. Fossils have been the most important means of correlation because, as a result of evolution , rock strata of approximately equal age exhibit similar flora and fauna. Dating and correlation of stratified rocks by means of fossils is called stratigraphic paleontology. See also dating .
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"stratigraphy." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stratigraphy." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-stratigr.html "stratigraphy." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-stratigr.html |
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stratigraphy
stratigraphy
1. The branch of the geologic sciences concerned with the study of stratified rocks in terms of time and space. It deals with the correlation of rocks from different localities. Correlation methods may involve the use of fossils (biostratigraphy), rock units (lithostratigraphy), or geologic-time units or intervals (chronostratigraphy). 2. The relative spatial and temporal arrangement of rock strata. |
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AILSA ALLABY and MICHAEL ALLABY. "stratigraphy." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "stratigraphy." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-stratigraphy.html AILSA ALLABY and MICHAEL ALLABY. "stratigraphy." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-stratigraphy.html |
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stratigraphy
stratigraphy The branch of geology concerned with the formation, chronology, and correlation of strata deposited on the surface of a planet or other body. Through the use of stratigraphy, the geological history of the body can be worked out.
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"stratigraphy." A Dictionary of Astronomy. 1997. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stratigraphy." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O80-stratigraphy.html "stratigraphy." A Dictionary of Astronomy. 1997. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-stratigraphy.html |
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stratigraphy
stratigraphy Branch of geology concerned with stratified or layered rocks. It deals with the correlation of rocks from different localities using fossils and distinct rock types.
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Cite this article
"stratigraphy." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stratigraphy." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-stratigraphy.html "stratigraphy." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-stratigraphy.html |
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