Purpose of this master thesis is to define the geological setting and complement the existing state of research of the Iška alluvial fan area and catchment areas of Smoligojnik, Draščica and Želimeljščica at the south-east part of the Ljubljansko barje. At the same time the purpose is also to give the interpretation of the hydrogeological setting of the aforementioned areas.
Iška alluvial fan and the Smoligojnik, Draščica and studied area of Želimeljščica catchments are located at the southern part of Ljubljansko barje. Structural faults with NNW-SSE direction are present at the area. Rocks that are present at the area are of Permian-Carboniferous, Lower Triassic, Carnian and Norian-Rhaetian eras. Iška alluvial fan and the marhes of Ljubljansko barje sediments are represented by Quaternary era with distictinct contrast in hydraulic permeability.
In the area of Smoligojnik, Draščica and Želimeljščica catchments 69 springs were mapped whereas in the area of Iška alluvial fan 53 were mapped. Electrical conductivity and the range of measured values in the Iška area are mostly linked to contamination, whereas at the aforementioned catchments the conductivity is linked to present lithology. Correlation between pH and other measured parameters is low. Temperature of the water at the springs is linked to sun exposure of the microlocation.
Želimeljščica, Draščica and Smoligojnik catchment is characterised by dispersed groundwater flow, which is in larger scale affected by structural faults. Geomorphological watershed and underground watershed differ one from another in the area. Hydrogeological units are directly linked to lithology, whereas the skitian and norian-rhaetian rocks are the one that have the highest amount of springs.
Existing classifications and the explanations of the »barjanska okna« spring formation are not suitable and are in multiple cases mutually exclusive. The proposed explanation of »barjanska okna« springs formation is linked to sedimentological heterogeneity and stratification rather than potential faults within sediments, alluvial and marshal sediments contact or hidden groundwater inflows from bedrock.