Reactions in fluid inclusions in plagioclase: thermodynamic modelling, constrains on PT paths and a natural example

摘要

Thermodynamic modelling illustrates that reactions in inclusions between the entrapped fluid and a plagioclase host do take place at retrograde metamorphic conditions. The general form of the reactions is Plagioclase + Fluid = Products. The composition of both the plagioclase and fluid put important constrains on the occurrence of those reactions. Valuable petrogenetic information can be derived from the identification of these processes in fluid inclusion, and more precise estimation of PT conditions during earlier metamorphic stages of fluid entrapment can be obtained.