Determination of chloride anions in fluid inclusions from quartz (Madan ore district, Bulgaria)

摘要

Low Cl~- and other anion concentrations in the aqueous phase of fluid inclusions in quartz (Krushev Dol Pb-Zn deposit, Madan ore district, Rhodope Mountains, Bulgaria) were determined by ion chromatography of solutions obtained by bulk leach-ing. After optimizing of the analytical procedure decrepitation was found to be the best technique for opening the fluid inclusions prior to chromatographic analysis. The best leaching agent was proved to be 0.01 M CH_3COOH which was capable of leaching all cations and anions from the inclusions content as was estimated by ion charge and mass balance in the leachate. The acetic acid used for cleaning the mineral sample and for ions' leaching neither damaged the successive anions detection, nor saturated the chro-matography column. By combining ion chromatography and microcryoraetry, the real Cl~- concentrations, as well as some cations' concentrations, in the ore-forming fluid were determined.