Related to the thermodynamic stability of clay minerals at low temperatures
you may wish to look into

Lippmann (1977) N Jb Mineral Abh

or some approaches published in the 80s in GCA.

Good luck, Michael

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Dr. Michael E. Böttcher
Department of Biogeochemistry
Max-Planck-Institute for Marine Microbiology
Celsiusstr.1
D-28359 Bremen
Voice:  (+49)421-2028-632
Fax:    (+49)421-2028-580
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