PŮVOD A CHEMICKÉ SLOŽENÍ FLUID POVARISKÉ HYDROTERMÁLNÍ MINERALIZACE NA LOKALITĚ ZLATÝ DŮL U HLUBOČEK (SPODNÍ KARBON NÍZKÉHO JESENÍKU)
Origin and chemical composition of fluids of hydrothermal ore veins at historical deposit Zlatý důl near Hlubočky (Lower Carboniferous of the Nízký Jeseník Upland) were studied using petrography, microthermometry and crush-leach analysis of fluid inclusions and analysis of stable isotopes of oxygen and carbon in carbonates, oxygen in quartz and sulphur in sulphides. Studied mineralization has epithermal and partly mesothermal character (Th = < 50 to 293 °C). The H2O-NaCl-CaCl2 system is mostly enclosed in the primary fluid inclusions in minerals of post-Variscan ore veins. These fluids had low to medium homogenization temperatures (68 to 293 °C) and moderate to high salinities (19–27 wt. % NaCl eq.). In contrast, low to moderate salinity (0–10 wt. % NaCl eq.) fluids of the system H2O-NaCl-KCl-(MgCl2-FeCl2) with low homogenization temperatures (< 50 to 110 °C) were enclosed in secondary fluid inclusions. The main source of water was probably evaporated seawater for older fluids. The source of carbon was in carbon of the homogenized Earth’s crust and partly in carbon of organic matter. Meteoric water is the main source for younger fluids. Origin of sulphur of sulphides is in the surrounding Lower Carboniferous sediments (shales). The high content of SO4 in fluids hosted by Fe-rich dolomite suggests the origin of the fluids in the evaporated Permian basins. Studied older quartz-galena vein is probably Variscan in age. Genetically similar mineralization can be found also at other localities in the Moravo-Silesian Lower Carboniferous (Culm, siliciclastics of the Lower Carboniferous age).