Hydrogeologiczne warunki odpływu podziemnego na Roztoczu Zachodnim

Abstract

HYDROGEOLOGICAL CONDITIONS OF GROUND-WATER DISCHARGE IN THE WEST ROZTOCZE REGIONSummaryThe article presents the results of the investigations made on ground-waterdis charge within the West Roztocze Region. In this area the author carried out his hydrogeological research in the years 1966–1971, and that on ground-water discharge in the years 1966–1969. The investigations were concentrated within seven catchment areas, whose source and alimentation regions are in the West Roztocze Region. Ground water occurs here in the Upper Cretaceous formations (Santonian, Campanian, Maestrichtian), and in the Tertiary formations represented by the Lower and Upper Tortonian and the Lower Sarmatian deposits. The occurrence of these formations is shown in Fig. 1.Fissures in the rocks of both formations are the main circulation system for ground water. The geological research allowed the following three kinds of fissures to be distinguished:– fissures of a NW–SE direction which is the main tectonic direction in the Roztocze Region;– fissures of a perpendicular NE–SW direction;­– interlayer fissures, parallel to the strike and dip of beds.The fissures of the first and the second directions cut the rock complexes of Cretaceous and Tertiary age, thus making one circulation system connected hydraulically.The drainage range of the individual catchment basins is presented in Fig. 2. Within the catchment basins (Fig. 3) seven water gauges have been installed, on which daily flows have been read off, and periodical hydrometric measurements executed to construct the appropriate consumption curves. The differentiation into the underground and surface discharges has been made according to the method of cutting inflow waves. The values of unit discharge are presented in Table 1. The comparison of the coefficients of surface runoff, ground-water discharge and; retention is shown in Table 3, and the mean comparative values of the coefficients of precipitation, discharge, retention and losses – in Table 4.