ASGP (2001), vol. 71: 125-134

CHEMICAL COMPOSITION AND ORIGIN OF IONIC RATIOS IN THE IWONICZ ANTICLINE MINERALIZED GROUNDWATERS (POLISH OUTER CARPATHIANS)

Adam POROWSKI

Department of Hydrogeology, Institute of Geological Sciences Polish Academy of Sciences, Twarda 51/55, 00-818 Warsaw, e-mail: adamp at twarda.pan.pl

Porowski, A., 2001. Chemical composition and origin of ionic ratios in the Iwonicz anticline mineralized groundwaters (Polish Outer Carpathians). Annales Societatis Geologorum Poloniae, 71: 125-134.

Abstract: One of the generally distinguished types of mineralized groundwaters are oil-associated waters, the so-called oil-field brines. The position of mineralized groundwaters of the Iwonicz anticline occurring in the immediate vicinity of oil fields makes it possible to include them among waters of this type. Considerations concerning the waters' chemical composition and ionic ratios using BDP plot and Stiff's diagrams certify to this preliminary conclusion. Because the flysch sediments were deposited in the sea and the composition of seawater is considered to have been constant since the Cambrian, the comparison of seawater chemical composition and of mineralized waters of the Iwonicz anticline has been presented. Analysis of ionic ratios of main and specific components as well as seawater evaporation trajectories (S-E-T) indicates genetic similarities between these two water types. At the same time processes of mixing with fresh water have been noticed. This allows to set forth the hypothesis that the recent chemical composition of the Iwonicz anticline mineralized waters, undoubtedly belong- ing to "oil-field brines", stays under considerable influence of "old" seawater (connate water) and fresh water of the recent hydrologic cycle.