Dear Micha,

sorry that the discussion went in the wrong direction. As I already mentioned
I am surely not an expert on the carbonate stuff, however, on a chemical view
I am rather sure that demagnetisation does not influence the delta value. The
reasons for this is the following:

1. Demagnetisation involves only the orientation of the electron spins. No
chemical reaction takes place.
2. Change in delta values involves preferential release of the lighter (or
heavier) element and thus chemical reactions have to take place. Concerning
only demagnetisation (and not release of organic matter or carbonates) no
chemical reaction should take place.

Kind regards

Bruno

Dr. Bruno Glaser
Insitute of Soil Science and Soil Geography
University of Bayreuth
D-95440 Bayreuth
Germany
.