Karst hydrogeology of the Untersberg massif and its interaction with the porous aquifer in the adjacent Salzburg Basin

A new understanding of the karst hydrogeology of the Untersberg massif and its interaction with the adjacent Salzburg Basin challenges previous assumptions. Contrary to earlier hypotheses, this study finds no evidence that karst water from the Untersberg infiltrates into the porous aquifer of the basin. Instead, it reveals that the Fürstenbrunn spring, a significant karst spring in the area, exhibits unusual behavior with a mean residence time of approximately 0.4 years and highly constant water temperature and electrical conductivity. The study also shows that groundwater fluctuations in the basin occur even during winter when discharge from the Untersberg karst system is low, indicating that rainfall is the dominant source of recharge further into the basin. The research utilized tracer tests, stable isotope analysis, and hydrochemical data to shed light on these complex interactions.

Reischer, M., Bichler, B., Spötl, C., Höfer-Öllinger, G., & Wyhlidal, S. (2015). Karst hydrogeology of the Untersberg massif and its interaction with the porous aquifer in the adjacent Salzburg Basin. Austrian Journal of Earth Sciences, 108(2). https://doi.org/10.17738/ajes.2015.0014