Coral skeletons

Initial U concentration. If uranium concentration has changed as a result of diagenetic reactions, one may, in principle detect this by comparison between uranium concentrations in modem corals and their fossil counterparts. Early work documenting and studying uranium concentrations in corals is extensive (e g., Barnes et al. 1956 Tatsumoto and Goldberg 1959 Veeh and Turekian 1968 Schroeder et al. 1970 Thompson and Livingston 1970 Gvirtzman et al 1973 Amiel et al. 1973 Swart 1980 Swart and Hubbard 1982 Cross and Cross 1983). This broad body of data shows that primary surface coral uranium concentrations lie between 1.5 and 4 ppm (see Fig. 1). Concentrations appear to be species dependent (Cross and Cross 1983). Furthermore, uranium concentrations vary within individual coral skeletons (Schroeder et al. 1970 Shen and Dunbar 1995 Min et al. 1995). 

Roy, D. M. Linnehan, S. Hydroxyapatite Formed from Coral Skeleton Carbonate by Hydrothermal Exchange. Nature (London) 1974,247, 220. 

Dodge, R.E. and T.R. Gilbert. 1984. Chronology of lead pollution contained in banded coral skeletons. Mar. Biol. 82 9-13. 

Pleistocene coral skeletons. Ph. D. Thesis Brown University, Providence, Rhode Island (1973). 

Buchsbaum, Pearse, V. Incorporation of metabolic CO2 into coral skeleton. Nature 228,... 

Larkum, A. W. D., High rates of nitrogen fixation on coral skeletons after predation by the crown of thorns starfish Acanthaster planci, Mar. Biol., 97, 503, 1988. 

Smith S.V., Buddemeier R.W., Redaije R.D. and Houck J.E. (1979) Strontium-calcium thermometry in coral skeletons. Science 204, 404-407. 

Swart P.K. and Hubbard J.A.E.B. (1982) Uranium in scleractinian coral skeletons. Coral Reefs 1, 13-19. 

Weil S.M., Buddemeir R.W., Smith S.V. and Kroopnick P.M. (1981) The stable isotopic composition of coral skeletons Control by environmental variables. Geochim. Cosmochim. Acta 45, 1147-1153. 

Constantz, B., and Weiner, S. (1988) Acidic macromolecules associated with the mineral phase of Scleractinian coral skeletons. J. Exp. Zool. 248, 253-258. 

Thin sections of blue coral and red soft coral can be capped and backed with plastic to give a smooth, shiny surface (Fig. 11.7). The main body of a coral skeleton of CoraUium, which can be very thick, can be carved into statues and figures of a substantial size -... 

Gorgonin A hom-like hard proteinaceous material, similar to keratin, that makes up all or part of some coral skeletons. 

Crossland, C. J., and Barnes, D. J. (1976). Acetylene reductionhy coral skeletons. Limnol. Oceanogr. 21, 153-156. 

Regeneration of organic nitrogen may occur in various components of the reef including within the diverse symbiotic associations (see Section 2.5). In addition to the surrounding sediments (DiSalvo, 1969 Entsch et al., 1983 Rasheed et al., 2002), structures on the reef proper may be important sources of regeneration of nutrients, including porewater within the coral skeletons themselves (Risk and... 

Davey, M., Holmes, G., andjohnstone, R. (2008). High rates of nitrogen fixation acetylene reduction on coral skeletons foUowing bleaching mortality. Coral Refs 27, 227—236. 

Ferrer, L. M., and Szmant, A. M. (1988). Nutrient regeneration by the endolithic community in coral skeletons. Proc. (6th) Int. Coral Reef Symp. 1—4. 

Muscatine, L., Goiran, C., Land, L., Jaubert, J., Cuif, J. P., and AUemand, D. (2005). Stable isotopes (delta C-13 and delta N-15) of organic matrix from coral skeleton. Proc. Natl. Acad. Sci. USA. 102(5), 1525-1530. 

Bar-Matthews M., Wasserburg G. J., and Chen J. H. (1993) Diagenesis of fossil coral skeletons—correlation between trace-elements, textures, and U-234/U-238. Geochim. Cos-mochim. Acta 57, 257-276. 

Two of these studies also looked at boron incorporation into the coral skeleton and observed that it also appears to be, at least in part, related to temperature (Sinclair et al., 1998 Fallon et al., 1999). The fact that at least four elements follow a seasonal pattern related to temperature suggests that elemental incorporation in coral skeletons is linked to calcification and is not simply driven by a thermodynamic temperature effect. If this applies generally, than all of the coral metal paleothermometers will have to be applied with attention to the possibihty of distortions caused by growth factors. 

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