e/Delta-O-18

Information
has gloss	eng: \| style="float:right" \| \|- \| \|- \| \|} In geochemistry, paleoclimatology and paleoceanography δ18O or delta-O-18 is a measure of the ratio of stable isotopes 18O:16O. It is commonly used as a measure of the temperature of precipitation, as a measure of groundwater/mineral interactions, as an indicator of processes that show isotopic fractionation, like methanogenesis. In paleosciences, 18O:16O data from foraminifera and ice core are used as a proxy for temperature. The definition is, in "per mil" (&permil;, parts per thousand): :\delta ^18}O = \Biggl( \frac\bigl( \frac^18}O}^16}O} \bigr)_sample}}\bigl( \frac^18}O}^16}O} \bigr)_standard}} -1 \Biggr) * 1000\ ^o}\!/\!_oo}
lexicalization	eng: Delta-O-18
lexicalization	eng: δ<sup>18</sup>O
instance of	(noun) a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust atomic number 8, oxygen, O