Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)
Hydrogeology bodies and regional groundwater flow in the Bohemian Karst
Abstract
Extensive hydrogeologic research of the Bohemian Karst was carried out between the years 1995 and 1999. Previous available archive data were complemented by field measurements. The most interesting new research results are as follows: One regional, mostly confined aquifer occurs within the area. It is represented typically by pure limestones of Lochkovian and Pragian formations. The aquifer permeability decreases from NW to SE due to changes in limestone facies. Regional groundwater flow is predominantly parallel with the main synclinorium axes. The results of research support the idea that groundwater flow reaches the depth up to 600 m. Less permeable limestones and shales, underlying and overlying the regional aquifer, represent aquitards. Groundwater flow is limited only to shallow weathered and fissured zones there. Storativity of the regional aquifer is about 3-7%. Therefore, the hydraulic diffusivity is high enough to cause responses in piezometric surface within the whole regional aquifer in a few days. On the contrary, in the unsaturated zone the period between a precipitation event and a groundwater level change can last up to one month.
