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Dating of cave sediments and reconstruction of karst morphology of the Nízké Tatry Mts
Kadlec, Jaroslav ; Danišík, M. ; Hercman, H. ; Pruner, Petr ; Chadima, Martin ; Schnabl, Petr ; Šlechta, Stanislav ; Grygar, Tomáš ; Granger, D.
The paleomagnetic polarities were measured both in clastic and chemogenic cave sediments preserved in eleven horizontal cave levels occur at different alitudes in the Jánska, Demänovská and Mošnica karst valleys in the Nízké Tatry Mts. Based on the obtained polarity data were are able to distinguish cave sediments deposited during the Brunhes, Matuyama and Gauss chrons. The stratigraphic interpretation was partly verified by U-series datings of speleothems preserved in the sedimentary sections. Except for the horizontal cave levels located in karst valleys, additional cave systems were formed at extremly high alitudes in the Nízké Tatry Mts. Preliminary data show predominantly reverse paleomagnetic orientations in fluvial activity in these caves and deposition of clastic sediments during Gilbert Chron.
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Study of stagnant water occurrences and dripping waters in caves: Chemical composition and remarks to corrosion of dripstones
Zeman, Ondřej ; Bruthans, J. ; Filippi, Michal ; Vysoká, H.
Slight stagnant water occurrences (drops) were studied in four caves in the Czech Republic and Slovakia. Major components were analyzed (Na+, K+, Ca2+, Mg2+, SO42-, Cl-, NO3-), pH, conductivity and temperature were measured in the field. Results are shown in table 1. Waters coming from condensation differs by higher amount of sulphate and some other components if compared with dripping waters.
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Environmental tracers (18O, 3H, CFCs, SF6) exploitation for study of mean residence time and flow pattern of dripping water and karst springs (Moravian Karst)
Bruthans, J. ; Zeman, Ondřej ; Jež, M. ; Himmel, J. ; Buzek, F. ; Melková, J. ; Oster, H. ; Geršl, M.
Mean residence time and flow pattern was studied in unsaturated zone of Ochoz Cave in southern part of Moravian Karst by means of 18O in the years 2001 to 2003. The results of study showed relatively long residence time in the unsaturated zone (about 50% komponent with residence time exceeding one year). The proportion components coming from different reservoirs were computed from two components (soil/epikarst; meltwater). The results clearly indicate, that more than 50% of water (nearly 100% in 2003) in dripping waters was derived from soil/epikarst water, which originate from (late) summer precipitations (heavy 18O content)! It means that infiltrating snowmelt water was expelling (by piston flow effect) the summer water from soil and/or epikarst. Water from snowmelt was then lost by evapotranspiration in summer time. If this effect is common in Langer period, it can change composition of d18O in dripping waters and hence also in dripstones precipitating from these waters.
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