Deprecated: Function get_magic_quotes_gpc() is deprecated in /home/isthin5/public_html/addon-domains/speleogenesis.info/include/functions1.php on line 943
Abstract:

 

Water circulation in Niedźwiedzia Cave system is complicated. The system is fed by direct infiltration of precipitation, infiltration from the surface stream and, possibly, by rising flow from deep sources. The cave is drained by system of karst springs in the Kleśnica stream valley, but some part of water flows across border ridge and occurs in Morava stream valley, Czech Republic (Ciężkowski et al. 2009). We tried to use tritium and stable isotopes to describe hydrology of the cave system and analyzed 155 water samples for stable isotopes and 38 water samples for tritium content. The Niedźwiedzia Cave system is composed of three levels of halls and galleries. In the upper level, stable isotope composition in drip water plots close to the local meteoritic water line (LMWL) on the δ18O vs δD diagram. It varies during the year similar to stable isotope composition of precipitation (i.e. low δ18O values during winters and higher δ18O during summers). The delay between isotopic signal in precipitation and drip water is ~10–14 days and this can be interpreted as a time of infiltration from the surface to the cave upper level. The correlation between isotopic composition of precipitation and drip water is not observed in the lower level of the cave system. There isotopic composition of drip water is more stable during the year. We use tritium dating method to estimate the age of this water. It has shown that infiltration time to the lower level is 1.4±0.3 year. The “oldest” water was found in karst spring draining the cave system. The estimated transit time is 3–4 years and suggest admixture of some “old” water that was not sampled in the cave.