I have conducted a gravity survey of the Povir and Škocjanske jame area in order to determine the gravity anomaly. Measurements above the Škocjanske jame system, where the cave and conduit geometry is known, were taken on 205 points. The influence of latitude, height, topography, Earth tide an gravimeter drift were removed with appropriate corrections and reductions. Trend surface method for separation of gravity field was determined to be more suitable on the basis of comparison with the modelled anomaly in IGMAS+. Local anomaly map clearly shows two major negative anomalies above the Martelova dvorana (11th largest cave chamber in the world) and Šumeča jama, as well as a small negative anomaly above the Hankejev kanal. Measured negative anomaly is slightly lower than the modelled value, which could be a consequence of model simplification or missing mass deeper or shallower in relation to the cave system. I have also conducted multiphase gravity measurements on 119 points in the Povir area, where air blowing from beneath the ground that occurs at large rainfall events indicates the existence of a large cave system beneath the village. Local anomaly map exhibits a large negative anomaly in proximity of the highway and two smaller anomalies E and W of the village. The absence of a negative anomaly in the village centre refutes the assumption of a large cave system underneath the village, which means that the air gusts are related to a system of fissures. I have modelled the gravity response of a cave and a surface morphological depression filled with sediments, that represents the most plausible source of the anomaly. Due to extreme drought conditions and a total absence of large rainfall events the calculation of groundwater mass flux variations, that is based on continuous gravity measurements, was not implemented in the Master's thesis, but the measurements will be continued.
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