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Magnetic fabric and mineralogy of cave deposits in Botovskaya Cave (Eastern Siberia, Russian Federation)
Kadlec, Jaroslav ; Hercman, H. ; Chadima, Martin ; Lisá, Lenka ; Oberhänsli, H. ; Osintsev, A.
The Botovskaya Cave is a typical example of a two-dimensional maze with a total length of explored passages exceeding 60 km, which represents the longest limestone cave system in the Russian Federation. The clastic cave sediments filling the cave passages differ in both mineral and mineral magnetic properties and were deposited under different hydrological conditions. The older portion of the clastic cave fills was derived from overlying sandstones, whereas the properties of younger cave sediments show closer affinity to the soils and weathering products originating on the sandstone plateau above the cave. The cave sediments underwent repeated periods of deposition and erosion during the Tertiary and Pleistocene.
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Valley incision in the Nízké Tatry Mts. (Slovakia) estimated based on paleomagnetic and radiometric cave sediment datings
Kadlec, Jaroslav ; Bella, P. ; Čížková, Kristýna ; Granger, D. E. ; Hercman, H. ; Holúbek, P. ; Chadima, Martin ; Orvošová, M. ; Pruner, Petr ; Schnabl, Petr ; Šlechta, Stanislav
Up to eleven horizontal cave levels occur at different altitudes in Jánska, Demänovská and Mošnická karst valleys in the Nízke Tatry Mts. Most of the caves are filled with allochthonous sediments transported from the area formed mostly by granite. The cave levels were filled with fluvial sediments in dependence on the valleys incision caused by Neogene and Pleistocene uplift of the mountain range. The fluvial sediments are intercalated with, or capped, by flowstone layers in the caves. The paleomagnetic polarities measured both in clastic and chemogenic sediments indicate the age of deposition. Based on obtained polarity data we are able to distinguish cave sediments deposited during the Brunhes, Matuyama and Gauss chrons. The paleomagnetic interpretation was partly verified by U-series datings of flowstones preserved in the sedimentary sections. Except for the horizontal cave levels located in the karst valleys, additional large cave systems were found at extremely high altitudes in the Nízke Tatry Mts. 600–700 m above the lowest horizontal cave level.
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The study of sediments and speleothems in the Zbrašov Aragonite Caves
Bosák, Pavel ; Šlechta, Stanislav ; Hercman, H. ; Pruner, Petr
The numerical dating of hydrothemal speleothems (doughnuts) from locality At Crocodile gave older data than was published in the literature: 123 to 127 thousand years (with range 108 to 144 thousand years). Speleothems crystallized in the time of climatic optimum of the last interglacial period (Eemian) corresponding to the marine isotope stage (MIS) 5e. Clastic sediments from excavations in the area At Crocodile show normal paleomagnetic polarity in all samples with nearly recent magnetic field directions. Studied sediments cover block of hydrothermal speleothems fallen from the wall and therefore they must be younger than 108 thousand years.
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Using the dye tracer for visualization of preferential flow in macro- and micro-scale
Kodešová, R. ; Němeček, K. ; Kodeš, V. ; Žigová, Anna
Study is focused on the visualization of the preferential flow in different soil types and their horizons using the dye tracer experiment. The field ponding dye infiltration experiments were performed in two soil types: Haplic Luvisol and Haplic Cambisol. In addition, the thin soil section were made and micromoprphological images were used to study soil aggregate structure and dye distribution in microscale. Images of the dye patterns (taken in macro- and micro-scales) documented very different nature of the preferential flow in different soil types and also within the soil profiles.
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