Hi Martin,

equilibrium carbon isotope fractionation between dolomite and CO2
at sedimentary temperatures has been treated theoretically by Golyshev
et al. (1981). However, the calculations are only valid for ideal
dolomite. The influence of

excess calcium or lattic distortion has not been evaluated. Kinetical
studies has, to my knowledge, not been published, yet. Additionally,
at lot of isotope data exist for natural co-existing dolomite-calcite
pairs.
See also Land (1980).


Cheers
Michael

******************************************************************
Dr.  Michael E. Boettcher
Biogeochemistry
Max-Planck-Institute of Marine Microbiology
Celsiusstr.1
D-28359 Bremen, FRG
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