Difference between revisions of "Chalk"
From Conservapedia
(Category (case), links) |
|||
| Line 1: | Line 1: | ||
[[Image:Four of the Seven Sisters.jpg|thumb|200px|Four of the "Seven Sisters" along the [[Sussex]] coast, [[England]]]] | [[Image:Four of the Seven Sisters.jpg|thumb|200px|Four of the "Seven Sisters" along the [[Sussex]] coast, [[England]]]] | ||
| − | '''Chalk''' is a white, sedimentary rock, composed of [[calcium carbonate]]. One of | + | '''Chalk''' is a white, sedimentary rock, composed of [[calcium carbonate]]. The calcium carbonate originates from the calcareous liths deposited by blooms of species of [[coccolithophore]] [[phytoplankton]]. |
| + | One of the most dramatic outcrops of chalk is along the south coast of [[England]] where it forms the "white cliffs of [[Dover]]", the Seven Sisters and parts of Englands [[Jurrasic Coast]], now a [[World Heritage Site]] in reckognition of its unusual geology. | ||
| − | + | As a useful commodity, chalk has been replaced by other substances. For example, the "chalk" that is used in blackboard writing or in sidewalk chalk is actually [[gypsum]]. | |
[[Category:Sedimentary Rocks]] | [[Category:Sedimentary Rocks]] | ||
Revision as of 12:27, August 8, 2008
Chalk is a white, sedimentary rock, composed of calcium carbonate. The calcium carbonate originates from the calcareous liths deposited by blooms of species of coccolithophore phytoplankton. One of the most dramatic outcrops of chalk is along the south coast of England where it forms the "white cliffs of Dover", the Seven Sisters and parts of Englands Jurrasic Coast, now a World Heritage Site in reckognition of its unusual geology.
As a useful commodity, chalk has been replaced by other substances. For example, the "chalk" that is used in blackboard writing or in sidewalk chalk is actually gypsum.
