Thanks a lot for comments and suggestions regarding CO2 analysis from
carbonates.
It is clear that the optimal experimental design as usual depends on what
results one needs. Learned a lot from the great list members!

Can anyone comment on the size of the error that oxygen isotopes in water
may add to 13C/12C measurements of CO2 from a carbonate?
Time aspects would be nice to learn about as well. If CO2 is liberated
within an hour - is there time for equilibration with water oxygen then?

I guess the answers depend on and can be divided into:
*       the impact oxygen isotopes have on the Craig correction formula
*       on the actual ratios of oxygen isotopes in water and carbonate
*       the amount of water that is allowed to exchange oxygen atoms with
the liberated CO2 (unless large exsess of water)
*       time from liberation of CO2 to equilibrium with water oxygen

Comments appreciated,

Lars
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