OBRAZ FIZYCZNY ZWIERCIADŁA WÓD PIERWSZEGO POZIOMU WODONOŚNEGO W ŚWIETLE BADAŃ METODĄ TOMOGRAFII ELEKTROOPOROWEJ (ERT)

Abstract

PHYSICAL IMAGE OF WATER TABLE DETERMINED BY THE ELECTRICAL RESISTIVITY TOMOGRAPHY (ERT) METHOD

Abstract. The paper presents the results and interpretation of Electrical Resistivity Tomography (ERT) study of the first aquifer. The study was carried out in the Warsaw region on three selected test fields with different geological structure and hydrogeological conditions: two in the Wisla River valley (“Józefów” and “Tarchomin”) and one in a postglacial upland in Warsaw (“Pole Mokotowskie”). The river valley aquifers are unconfined, whereas in the upland, the first aquifer is confined and under pressure. The results clearly show the presence of aquifers on the ERT image, but the positioning of the water level is not always precise. The precision depends on granulometry of sediments, resistivity contrasts, chosen method of resistivity measurement and morphology of low-resistivity sediments (e.g. Pliocene clays in the Warsaw area).