To establish standards for the palaeoenvironmental interpretation of scleractinian coral-bearing strata, the geochemistry of the three major trace-element constituents of living scleractinian coral skeletons is discussed in relation to possible controls on their concentrations. Experiments were conducted in which the Sr/Ca and Mg/Ca ratios of the seawater were altered and the resultant change in skeletal composition monitored. The partition coefficient of strontium KSr was shown to be linear, ranging from approximately half to over ten times the normal seawater Sr/Ca ratio. Increases in the magnesium concentration of seawater decreased KSr. Growth rates were increased through the addition of calcium and strontium, but decreased by magnesium. The sodium and magnesium contents of the skeleton were unaffected by their seawater concentrations relative to calcium or strontium. Magnesium, however, was affected by growth while sodium by salinity.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Earth-Surface Processes