Abstract
Some coelenterates of the class Hydrozoa and some anthozoan coelenterates from the subclass Octocorallia secrete skeletons of calcium carbonate. Skeletal carbonates of three hydrozoans and of two octocorals were analyzed for the stable isotopes of carbon and oxygen. The results suggest that each of these coelenterates deposits CaCO3 in oxygen isotopic equilibrium with seawater, and that at least one octocoral, Heliopora, has skeletal carbon in apparent isotopic equilibrium with atmospheric CO2. Two of these coelenterates, Millepora and Helipora, are significant contributors to the construction of coral reefs. Whereas δ18O of these corals is temperature dependent, δ13C is not obviously related to temperature. The δ18O-temperature relationship is not significantly different from the oxygen isotope paleotemperature scale developed by Epstein et al. (1953). These findings contrast with numerous analyses of the carbonate in scleractinian coelenterates, which have long been reported to deposit CaCO3 skeletons whose carbon and oxygen isotopic compositions are not in equilibrium with the external sea-water environment.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Literature cited
Bottinga, Y.: Calculation of fractionation factors for carbon and oxygen isotopic exchange in the system calcite-carbon dioxide — water. J. phys. Chem., Ithaca 72, 800–808 (1968).
Craig, H. and C. D. Keeling: The effects of atmospheric NO2[N2O] on the measured isotopic composition of atmospheric CO2. Geochim. cosmochim. Acta 27, 549–551 (1963).
Deines, P.: Mass spectrometer correction factors for the determination of small isotopic composition variations of carbon and oxygen. Int. J. Mass Spectrom. Ion Phys. 4, 283–295 (1970).
Deming, W. E.: Statistical adjustment of data, 243 pp. New York: Wiley and Sons 1943.
Emrich, K., D. H. Ehhalt and J. C. Vogel: Carbon isotope fractionation during the precipitation of calcium carbonate. Earth planet. Sci. Letters 8, 363–371 (1970).
Epstein, S., R. Buchsbaum, H. A. Lowenstam and H. C. Urey: Carbonate-water isotopic temperature scale. Bull. geol. Soc. Am. 62, 417–426 (1951).
—, —, — and —: Revised carbonate-water isotopic temperature scale. Bull. geol. Soc. Am. 64, 1315–1326 (1953).
Pearse, V. B.: Incorporation of metabolic CO2 into coral skeleton. Nature, Lond. 228, p. 383 (1970).
Revelle, R. and R. Fairbridge: Carbonates and carbon dioxide. Mem. geol. Soc. Am. 67, (1) 239–295 (1957).
Weber, J. N. and D. M. Raup: Fractionation of the stable isotopes of carbon and oxygen in marine calcareous organisms — the Echinoidea. Geochim. cosmochim. Acta 30, 681–736 (1966).
— and P. M. J. Woodhead: Carbon and oxygen isotope fractionation in the skeletal carbonate of reef-building corals. Chem. Geol. 6, 93–117 (1970).
Author information
Authors and Affiliations
Additional information
Communicated by J. Bunt, Miami
Rights and permissions
About this article
Cite this article
Weber, J.N., Woodhead, P.M.J. Stable isotope ratio variations in non-scleractinian coelenterate carbonates as a function of temperature. Mar. Biol. 15, 293–297 (1972). https://doi.org/10.1007/BF00401388
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00401388