The influence of NaCl and KCl on phase relations in metamorphosed carbonate rocks.

Abstract

Phase relations in metamorphic fluids containing chloride components are discussed on the basis of chemical potential diagrams. With reference to the influence of concentrated brines on the stability of mineral assemblages formed during the metamorphism of carbonate rocks, evidence is cited from fluid and solid inclusions in metasomatic quartz-calcite-tremolite veins in dolomitic marbles at Campolungo, Switzerland. Correlations are drawn between the field evidence and the experimental and theoretical data.-M.S.