3 research outputs found

    Impact of rainfall infiltration on groundwater recharge of a deep quaternary aquifer

    Get PDF
    Verification of recharge of groundwater in the deep Quaternary sand layers covered with leaky deposits of silt and clay has been implemented using mathematical modelling of the aquifer system in conditions of test pumping and during the 10 year exploitation of the Osijek well field Vinogradi. An analytical method for the identification of local parameters of the leaky aquifer is shown using the Excel program that enables usage of data from the relatively short term testing period, while at the same time suppressing external impacts. Boundary conditions and regional aquifer parameters have been verified by a numeric aquifer model, calibrated on the basis of three years of data from functioning field wells. The 96 mm average yearly recharge of rainfall infiltration into the aquitard was identified by validation of the model, based on information obtained from observation of groundwater levels in piezometers and in the pumped wells over a ten year period. At the end of the validation period, there was a 20 month break in pumping of the entire well field, and the measured recovery of groundwater levels provided an additional check on the results. Variation in the groundwater levels from particular layers, and water quality during exploitation are explained by the combined effects of closing of some of the well screens and the heterogeneity of the aquifer system.</p

    HYDROGEOLOGICAL CONDITIONS OF OCCURRENCE OF CLAY INTERBED WITHIN VARAŽDIN AQUIFER

    Get PDF
    Varaždinski vodonosnik zauzima krajnji zapadni dio heterogenih kvartarnih naslaga dravske doline. Šljunčani vodonosnik koristi se za potrebe vodoopskrbe većih naselja. Interpretacije strukture naslaga i hidrogeoloških odnosa ovog područja u zadnje vrijeme potaknuta su regionalnim problemima vodoopskrbe i zaštite izvorišta. Istraživanja su naročito usmjerena na glineni proslojak koji dijeli varaždinski vodonosnik na dva izolirana sloja šljunka. Provedena su geofizička mjerenja i izvedene su nove istraživačke bušotine. Ovim su istraživanjima došlo do novih spoznaja te omogućio detaljniji prikaz rasprostiranja glinenog proslojka.Varaždin aquifer is developed in the far western part of the heterogeneous Quaternary deposits in Drava basin. Water captured from this gravel aquifer is used for water supply of major cities. Recent regional problems of water supply and water source protection prompted new interpretations of the structure of deposits and hydrogeological relations in this area. Research has been focused especially on clay interbed that separates Varaždin aquifer in two isolated gravel layers. Geophysical measurements have been carried out followed by drilling of new exploration boreholes. These studies have shown new insights and enabled detailed display of clay interbed within Varaždin aquifer

    HYDROGEOLOGICAL SIGNIFICANCE OF RECESSION COEFFICIENTS AT THE EXAMPLE OF ISTRIAN SPRINGS

    Get PDF
    Hidraulički izvod koeficijenta recesije za shematizirani tip krškoga vodonosnika razvidno izražava hidrogeloške i geometrijske parametre o kojima ovisi veličina ovoga koeficijenta i na tom tragu predstavlja vrlo dragocjen parametar pri identifikaciji vodonosnog sustava. Na primjeru istarskih izvora Bulaž, Gradole i Fonte Gajo koeficijent recesije ukazuje da je slijev izvora Gradole višestruko puta veći od slijevova ostalih istarskih izvora.Hydraulic extract of discharge coefficient for the type of schematized karstic aquifer clearly expresses hydrogeological and geometrical parameters on which depends the value of this coefficient and is a very valuable parameter in the identification of groundwater system. On the example of Istrian springs Bulaž, Gradole and Fonte Gajo discharge coefficient indicates that the drainage area of Gradole spring is multiple times greater than the drainage area of other Istrian springs
    corecore