Isotopic equilibrium between shells and their environement.
The carbon-isotopic composition of shell carbonate is shown to be in isotopic equilibrium with bicarbonate dissolved in the water. By measurement of both 13C and 18O in a series of brackish-water shells a mean growth temperature can be deduced.
D000818:Animals; D001639:Bicarbonates / Q000032:analysis*; D002247:Carbon Isotopes / Q000032:analysis*; D002254:Carbonates / Q000032:analysis*; D008386:Marine Biology; D008974:Mollusca; D010103:Oxygen Isotopes / Q000032:analysis*; D014867:Water
D001639:Bicarbonates; D002247:Carbon Isotopes; D002254:Carbonates; D010103:Oxygen Isotopes; D014867:Water