Mineral, Thermal and Thermomineral Waters of Bosnia and Herzegovina

Abstract

Bosnia and Herzegovina, a country of Alpine orogene system, presents a terrain with a complex geological phenomenology and numerous mineral, thermal and thermomineral waters; there are 193 deposits of mineral, 57 thermal and 30 thermomineral waters with ca 400 natural springs and 170 drillholes and wells. The total yield of all deposits is 7,035 l/s, of which mineral waters contribute 4114 l/s, thermal 1828 l/s and thermomineral 1093 l/s. Drillings were performed in 50 deposits with natural springs and in 31 deposits without springs. Exploitation has been carried out in 47 deposits to establish the quality and quantity of these resources. The present use of mineral waters is in balneology, recreation, bottling and industrial use; thermal in balneology, recreation, bottling, water-supply, thermoenergetics and industrial use, and thermomineral in balneology, recreation, bottling, thermoenergetics and extraction of mineral raw materials. The total established power of 87 hydrogeothermal deposits is 251 MWt and potential power is ca 795 MWt with reference to 10 °C, while geothermal direct heat use is only about 22 MWt. Evidence clearly shows the potential of positive results of investigations and the sustainable and polyvalent use of these resources in numerous sites, though many obstacles make the feasibility of this application difficult. These waters are mostly renewable resources based on isotopic content and other data. There are a few waters of no meteoric origin in closed deep artesian horizons. All waters are dominantly prenuclear (“dead” waters—³H = 0). According to ¹⁴C content, a large number of waters are over 40,000 years old, with very slow circulation and long residence times in the aquifers, and they are naturally protected by insulating rocks as roof barriers to prevent any surface contamination of aquifers. Waters have various origins, content and concentration of constituents, and were formed in different rock ages and in complicated geological structures. There are specific waters of rare and effective physical and chemical composition which do not exist in surrounding countries. Mineral waters have a large range of TDS from 0.5 to 270 g/L, thermal from 0.15 to 0.8 g/L and the thermomineral from 1 to even 300 g/L; there is a great variety from the very acidic type (pH = 3) to hyperalkaline with pH = 12, with diverse contents of N₂, O₂, CO₂, H₂S composition with free and dissolved gases and different GWR. The CO₂ in most of the carbon acid waters, according to δ¹³C in the CO₂, is created at great depths and probably originates by thermal hydrolysis of marine carbonate rocks. In some deposits, the existence of higher homologues of methane and values of δ¹³C in CH₄ indicate an organic origin of CH₄ deriving from petroleum-gaseous deposits overlying ophiolitic rocks. Determining the plausible geological and geothermal models of terrain for the various types of groundwaters are basic theoretical and practical tasks, which allow the location of shallower wells for successful capturing of waters. Additional greater capacities of different groundwaters are possible to obtain by drillings of new deeper wells in almost all active mineral and hydrogeothermal deposits. It is of considerable interest to determine whether and in which sites and lithostratigraphic units there are as yet undiscovered hydrogeotherms of higher enthalpy in shallow and deeper horizons, particularly by investigating deposits with shallow drillings. Higher temperatures and greater yields have already been found in several deposits with shallow drillholes.