Groundwater characteristics and problems in carbonate rock aquifers

The lithology and tectonic structure of carbonate rocks are directly linked to the evolution of aquifers. Solubility is based on the dissolving ability of water, especially the carbon dioxide content, as well as on the dissolving readiness of carbonate rocks. Combined application of environmental and artificial tracers provides evidence on two main fields of hydrogeology: calculation of subsurface water storage and localization of recharge areas. Artificial tracing experiments usually show rapid flow characteristics in fractures and solution channels. In contrast, environmental isotopes and dissolved solids generally process the total aquifer. Hence, a comparison between natural and artificial tracing can be used to develop a model for aquifer dynamics. Concerning the localization of recharge areas, the effect of altitude on stable hydrogen and oxygen isotopes, the chemical constraints on rock-water interactions and artificial tracing should be applied in a synoptic way. Case studies are described from an Alpine karst massif and a coastal karst area in the Mediterranean region. (author). 3 refs, 6 figs, 1 tab