A tracer test was conducted with injection from the surface into a shaft in the central part of the aquifer. The results were compared to a previous tracer test with similar injection characteristics (the same tracer, injection into shaft vs karren) but with a significantly different vadose zone thickness. A conceptual model of flow and transport duality through the karst system was elaborated: part of the tracer flows rapidly through the primary drainage channels, while the other part is predominantly characterised by prolonged retention in less permeable zones. The results obtained support the idea that the thickness of the vadose zone has a very strong influence on residence times and dispersion.
COBISS.SI-ID: 43536685
Recent results of hydrogeological studies, including the research activities in Javorniki aquifer.
COBISS.SI-ID: 40276013
To estimate the outflow rate along the eastern ponor zone of Unica River , the discharge was measured upstream and downstream to the outflow zone. Seven velocity profiles were recorded with an Acoustic Doppler Current Profiler and the corresponding discharges were calculated. The measurements were taken within four hours during the flow recession following a partial flooding of the Planinsko Polje. Therefore, six outflow zones were evaluated with an outflow rate ranging between 1 m3/s and 5.6 m3 /s. The total loss of water along the eastern border summed up to 18 m3 /s under the given hydrological conditions. These results give new insight into the functioning of karst poljes and provide an important input for eventual future hydrological modelling of the area.
COBISS.SI-ID: 41880621
Introductiory review chapter in the book Advances in karst research : theory, fieldwork and applications, (Special publication - Geological Society of London) among other novel results, presents work and results obtained within the project. The cover picure of the book is from Planinska jama, made during the field work in the scope of the project.
COBISS.SI-ID: 43344429
The sub-surface flow path through the Postojnska jama cave system has been monitored with 7 stations distributed along the flow path, monitoring stage and temperature. We have used the stage data to model flow through the cave system with the program package SWMM, simulating the active parts of Postojnska jama with simplified geometry. From the comparison of stage observations and predictions, we identified key sections in the cave, which control the sub-surface flow, such as passage constrictions, sumps and by-passes. Using a formal inverse procedure, we determined the geometry of this key sections by fitting predicted to observed stages, and we achieved a very high degree of correlation.
COBISS.SI-ID: 40739373