ECOTERRA Journal of Environmental Research and Protection A hydrochemical approach to the mineral waters from the Eastern Carpathians Boglárka-Mercedesz Kis, Călin Baciu Faculty of Environmental Science and Engineering, University Babeş-Bolyai Cluj-Napoca, Romania. Corresponding author: B. M. Kis,
[email protected] Abstract. The Eastern Carpathians are renowned for their mineral water resources, exploited since long time for their therapeutic value. In the present paper we summarize the chemical findings of a research carried out on 104 mineral water spring in the Eastern Carpathians. Two major types of waters (Ca-Na- HCO3 and Na-Cl) were identified based on the analysis of the major ions. The overlapping chemical features give birth to the mixed type of waters found in the southern part of the Eastern Carpathians. All of the waters are associated to bubbling gases of CO2, CH4 or H2S. The chemistry of mineral waters is highly influenced by the type of rocks they are leaching. Considering this aspect the mineral waters from the Eastern Carpathians are mainly influenced by the Neogene to Quaternary volcanic rocks of the Călimani-Gurghiu-Harghita Mountains, the sedimentary deposits of the Transylvanian Basin and the flysch deposits of the Carpathian arc. Key Words: Eastern Carpathians, mineral waters, major ions, CO2. Introduction. When speaking abount mineral waters, or defining the notion of “mineral water”, three aspects must be taken into consideration: geological, medical and social aspects or recent trends on water consumption. These aspects, together with the actual definition of the „mineral water” has changed several times during history from the past until the present.