Dear Peter and isern,

less experimental work has been done on isotope fractionation upon
carbonate precipitation at low temperatures and especially from
seawater-like solutions.

A basic experimental paper is the work of Tarutani et al. (1969) on
the isotope fractionation upon formation of aragonite and the
influence of Mg substitution into the calcite lattice on 18O/16O
fractionation. Tarutani found no influence of precipitation
kinetics on oxygen isotope fractionation. However, I am certain that
this finding needs to be confirmed by a more detailed experimental
study!

For carbon isotopes, there is slightly more published work. See for
instance the paper by Chris Romanek et al. (1992) or the paper by
Turner (198i).

For theoretical relationships of isotope fractionation as a function
of temperature have a look into Golyshev et al. (1981; geoch. Int.)
and Zheng (1997; Chem. Geol).

If you need further references, just send me a mail.

Good luck!
Michael

PS: A PhD student of Prof. Yong-Fei Zheng is currently working on
isotope fractionation upon precipitation of carbonates. However,
I don t know if he uses seawater-like solutions.

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Dr. Michael E. Boettcher
Institute of Chemistry and Biology of the Marine Envrionment (ICBM)
Carl von Ossietzky University
P.O. Box 2503
D-26111 Oldenburg
FRG
Voice: +49-441-798-2534 (office)
                  -3403 (isotope lab)
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