WYKORZYSTANIE CHEMIZMU WÓD GŁĘBOKICH POZIOMÓW WODONOŚNYCH W REJONIE BEŁCHATOWA JAKO WSKAŹNIKA ICH PRZYDATNOŚCI DO LOKOWANIA DWUTLENKU WĘGLA

Abstract

USAGE OF CHEMISTRY OF DEEP AQUIFERS AS AN INDICATOR FOR THEIR SUITABILITYFOR STORAGE OF CARBON DIOXIDE IN BEŁCHATÓW REGION (CENTRAL POLAND)Abstract..Deep, saline aquifers used for the storage of CO2 must be covered by impermeable formations in order to prevent the migration of water into shallow zones. One of the methods of the assessment of the isolation degree of deep aquifers is the study of the chemical composition of waters. This method has been used at the first stage of the research program presented in this paper in the Bełchatów region (central Poland). Within this region several deep saline aquifers have been evaluated with respect to their storage potential represented by the geochemical maturity and isolation of saline waters measured by Na/Cl, Cl/Br ratios and TDS. Six types of groundwaters according to the degree of maturity and isolation have been identified, from the youngest waters with contact to meteoric waters (type 1 and 2) to the oldest, stagnant, highly mineralized brines (type 5 and 6). Saline aquifers of the Lower Triassic, Upper Triassic, Lower, Middle and Upper Jurassic, Cretaceous were examined. Between 518 and 4,530 m depth, these aquifers contain waters of 0.5–370 g/l of total dissolved solids (TDS). These waters are not an underground source of drinking water. The geochemical maturity of waters depends on the depth, the presence of the impermeable cover, the distance from the outcrops and also the presence of faults and fractures. Waters in the Jurassic reservoirs are of different types, from 1 and 2 which are not suitable for CO2 location to 3 and 4 (more suitable for CO2 location). The Triassic reservoirs are mostly of type 5 and 6 which are very suitable for CO2 location. This approach may be applied particularly in the preliminary studies not only due to its simplicity and low time consuming but also due to the savings of cost and time for the further studies of the reservoirs which may be excluded for storage of carbon dioxide using this method.