Vývoj povariských fluid v lomech u Nejdku, Jakubčovic a Bohučovic v Nízkém Jeseníku


Two different types of fluid were described in studied post-Variscan vein mineralization from Nejdek, Jakubčovice and Bohučovice quarries. First high salinity (between 18 and 28 wt. % NaCl eq.) and low temperature (ranging from 50 to 140 °C) fluids of H2O-NaCl-CaCl2 (±MgCl2) type, present in dolomite, sphalerite and calcite I, II, was originated from the highly evaporated seawater. Second low salinity (between 0 and 9 wt. % NaCl eq.) and low temperature (ranging from 40 to 80 °C) fluids of H2O-NaCl (±KCl) type, present in calcite III, was originated from the less evaporated seawater. Fluids represent moderate mixing with the sea or meteoric water and they also indicate slight to progressive interaction with the rocks (mainly illitization, dissolution of K-feldspar and albitization).

Klíčová slova:
Nízký Jeseník Upland; fluid chemistry; fluid inclusions; stable isotopes

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