Origin of the Badenian salts from East Slovakian basin indicated by the analysis of fluid inclusions

Chemical composition of the brines of primary fluid inclusions in sedimentary halite (from the boreholes: P-2, P-3, P-6, P-7 and P-8) of the Badenian evaporite of the Zbudza Fm. from East Slovakian basin indicates that the basinal brines belong to the Na-K-Mg-Cl-SO₄ type. The ratios of K+, Mg²⁺, and SO₄^2- ions are practically the same as they were in the Badenian seawater. Taking into account the information on the chemical evolution of seawater in the Phanerozoic (Kovalevich et al., 1998) and the calculations of this evolution for the Cenozoic (Zimmermann, 2000) it is suggested that the Badenian seawater was characterized by the reduced contents of Mg (by approximately 20%) and SO₄^2- (by approximately 40%) in comparison with the recent seawater. The postsedimentary recrystallization of salts occurred under the effect of buried brines, which inherited their composition from the primary basinal brines. The intensive recrystallization of salts occurred during the tectonic movements.