Gips: Verskil tussen weergawes
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Lyn 8:
[[File:White Gypsum - geograph.org.uk - 2503198.jpg|thumb|left|Veins of gypsum in the silts/marls of the Tea Green and Grey Marls, Blue Anchor, Somerset, UK]]
[[File:Chugwater gypsum veins.jpg|thumb|left|Veins of gypsum in the [[Chugwater Formation|Chugwater Group]], Wyoming]]
File:Chugwater gypsum veins.jpg
Gypsum is a common mineral, with thick and extensive [[evaporite]] beds in association with [[sedimentary rock]]s. Deposits are known to occur in [[stratum|strata]] from as far back as the [[Archaean]] [[eon]].<ref name="Cockell">{{cite journal|last=Cockell|first=C.S.|coauthors=Raven J.A.|year=2007|title=Ozone and life on the Archaean Earth|journal=Philisophical Transactions of the Royal Society A|volume=365|pages=1889–1901|doi=10.1098/rsta.2007.2049|url=http://rsta.royalsocietypublishing.org/content/365/1856/1889.full.pdf|accessdate=16 February 2011|issue=1856}}</ref><!--What about the Messinian evaporites?--> Gypsum is deposited from lake and sea water, as well as in [[hot spring]]s, from [[volcano|volcanic]] vapors, and sulfate solutions in [[Vein (geology)|veins]]. [[Hydrothermal]] [[anhydrite]] in veins is commonly hydrated to gypsum by groundwater in near surface exposures. It is often associated with the minerals [[halite]] and [[sulfur]].
{{Saadjie}}
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