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Hypogene caves in the Plavecký hradný vrch Hill (Western Slovakia, Central Europe) were formed by waters ascending along faults in fractured Triassic carbonates related to the horst-graben structure at the contact of the Malé Karpaty Mountains and the NE part of the Vienna Basin. The Plavecká jaskyňa and Pec caves mostly contain horizontal passages and chambers with flat corrosion bedrock floors, fissure discharge feeders, wall water-table notches, replacement pockets, as well as a few other speleogens associated with sulfuric acid speleogenesis. The low-temperature sulfuric acid development phases of the Plavecká Jaskyňa are also indicated by the presence of sulfate minerals (i.e., gypsum and jarosite). Subaerial calcite popcorn rims were precipitated from water condensation at the edges of feeding fissures that were still active as thermal vents when the water table dropped. Hydrogen sulfide involved in the sulfuric acid speleogenesis was likely derived from anhydrites and/or hydrocarbon reservoirs with sulfate-saline connate waters in the fill of the adjacent Vienna Basin. It ascended to the surface along deep-rooted sub-vertical fault zones at the contact of the Vienna Basin with neighboring mountains. Three cave levels at 295 to 283 m asl in the Pec Cave, and five levels at 225 to 214 m asl in the Plavecká jaskyňa corresponded to phases of stable local erosional base levels in the bordering part of the Vienna Basin, most likely during periods of strongly decelerated and/or interrupted subsidence. Cave levels separated by vertical differences of only a few meters may also be related to the Pleistocene climatic cycles. The subhorizontal parts of the Pec Cave are probably of late Early Pleistocene age (>0.99-1.07 Ma?). The two highest levels of the Plavecká jaskyňa developed during the early Middle Pleistocene (>600 ka). Fine-grained sediments in the passage at 225 m asl with normal magnetic polarity contain jarosite. The middle level of the Plavecká jaskyňa at 220 m asl was formed in the mid-Middle Pleistocene, while the lower and lowermost levels formed in the late Middle Pleistocene (>270 ka). The water table in the lowermost cave level probably dropped after the tectonic reactivation of the Podmalokarpatská zníženina Depression just in the front of a marginal horst structure of the Malé Karpaty Mountains. [ABSTRACT FROM AUTHOR]

This case study from the renowned Demänová Cave System in the Carpathians of Slovakia demonstrates that the conventional methods of fluvial sedimentology, combined with an allostratigraphic mapping and speleothem U‐series isotopic dating, can give unprecedented insights into the hydrological history of underground karst conduit. The deposits studied are a relic compound sidebar ranging from gravel to mud and encapsulating the conduit's hydrological history from the middle Pleistocene to the present time. A succession of 10 allostratigraphic units, time‐constrained by speleothems, are recognized in the sidebar deposits, and the corresponding morphodynamics of an evolving cave‐floor sedimentation are reconstructed in considerable detail. The subterranean river water stages recognized from the deposits, time‐constrained by flowstone layers and stalagmites, correlate with and add to the regional record of climate changes. Two distinct episodes of flow ponding (high‐stage slackwater conditions) are recognized and attributed to the independently documented downstream cave‐roof collapses, probably triggered by the Carpathian post‐orogenic earthquakes. This multidisciplinary study may serve as a useful methodological guide for the analysis of fluviokarstic deposits in speleological research and reconstruction of their hosting cave hydrological history. [ABSTRACT FROM AUTHOR]

Five stalagmites from the Demänová Cave System (DCS, Western Carpathians, Slovakia), spanning the period from 13,000 to 500 a BP, were analyzed for their oxygen and carbon stable isotopic composition of the calcite. The isotopic data obtained from several stalagmites located in one cave system allow us to separate the changes of regional/global importance from the local changes. Oxygen isotope ratios point to dynamic changes in the environment at the onset of the Holocene. Despite the local differences, carbon isotope data express the gradual and steady development of vegetation on the surface above the cave from the beginning of the Holocene until 6,000 a BP. The oxygen isotope values in the DCS stalagmites are higher than that derived from the Rayleigh distillation model until approximately 9,000 a BP, suggesting (1) an increase in the isotopic gradient to the east of Europe, probably caused by a different seasonality in precipitation amount or (2) different sources of meteoric water, transported from the Mediterranean and Black Sea region, in Central and Eastern Europe compared to the Western, circum-Atlantic part of the continent. The younger part of the DCS records falls in the range described by the model and points to the increasing role of the westerlies in the determination of the climatic conditions of Central Europe during middle- and late-Holocene. [ABSTRACT FROM AUTHOR]

Detailed analyses of speleothems collected in caves of the Demänová Valley, Nízke Tatry, Slovakia, have found significant variability in uranium concentrations and initial 234U/238U activity ratios, plus correlation between these variables. They are related to the ages of samples and their differing locations in the caves. Strong variability of initial 234U/238U activity ratios is the reason for serious limitations in applying the 234U/238U Regional Uranium Best Estimate method as an age estimator for speleothems older than the range of the 230Th/234U method (500 ka). The strong variability of uranium contents in speleothems, rocks and waters and their isotopic compositions allowed us to distinguish distinct periods with changes in water circulation paths or distribution/weathering degrees of deposits in surface alimentation areas or in the epikarst zone, that result from the more ready leaching of the 234U isotope from sediments. Periods characterised with higher initial 234U/238U activity ratios are most likely associated with the deposition of "fresh" colluvial deposits and/or soil development (potential uranium source) in the alimentation area. Gradual decrease of initial 234U/238U activity values indicate prolonged stable weathering and uranium leaching conditions. The Demänová results indicate periods of intensive erosion and "fresh" sediment deposition in the alimentation areas at ~120 ka, ~80-70 ka, and during the Holocene. [ABSTRACT FROM AUTHOR]

Karst systems can control the amount of water flowing on the surface and thus the fluvial erosional efficiency. Here, we used the ages of speleothems from the active cave system to determine the middle Pleistocene history of the entrenchment of the Demänová Valley. By referencing the vertical position of fluvially active and inactive cave passages to the valley bottom, we estimated the deceleration magnitude of the valley incision due to karst drainage through the Demänová Cave System. The well-developed karst system captures a significant volume of surface water and reduces surface erosion. This, in turn, causes a delay in the incision of the valley drained by the caves in comparison to the downstream positions (below the springs of sinking waters), where river-driven erosion dominates. Karst drainage has reduced the erosional efficiency in the inflow part of the Demänová Valley due to a hydraulic gradient among inputs and outputs of allochthonous waters, mostly during the middle and late Pleistocene. The cave level that contains the active underground segment of the Demänovka River, previously dated to ~350 ka, definitely existed earlier than 600 ka. The period from approximately 600 to 395 ± 5 kyr ago was characterized by relatively stable conditions with continuous deposition of flowstones, regardless of the climate episodes, including several glacial–interglacial cycles. • Relatively old age of fluvially active cave level • Long time of continuous speleothem growth, also during cold MIS • Average incision rate of valley floor from 64 to 83 m/Ma • Surface erosion delayed due to capture of water by a cave [ABSTRACT FROM AUTHOR]

Cold Wind Cave, located at elevations ranging between 1,600 and 1,700 m a. s. l. in the main range of the Nízke Tatry Mountains (Slovakia), is linked in origin with the adjacent Dead Bats Cave. Together, these caves form a major cave system located within a narrow tectonic slice of Triassic sediments. Both caves have undergone complex multiphase development. A system of sub-horizontal cave levels characterized by large, tunnel-like corridors was formed during the Tertiary, when elevation differences surrounding the cave were less pronounced than today. The central part of the Nízke Tatry Mountains, together with the cave systems, was uplifted during the Neogene and Lower Pleistocene, which changed the drainage pattern of the area completely. The formation of numerous steep-sloped vadose channels and widespread cave roof frost shattering characterized cave development throughout the Quaternary. In the Cold Wind Cave, extensive accumulations of loose, morphologically variable crystal aggregates of secondary cave carbonate ranging in size between less than 1 mm to about 35 mm was found on the surface of fallen limestone blocks. Based on the C and O stable isotope compositions of the carbonate (δ13C: 0.72 to 6.34 ‰, δ18O: -22.61 to -13.68 ‰ V-PDB) and the negative relation between δ13C and δ18O, the carbonate crystal aggregates are interpreted as being cryogenic cave carbonate (CCC). Published models suggest the formation of CCC in slowly freezing water pools, probably on the surface of cave ice, most probably during transitions from stadials to interstadials. Though the formation of these carbonates is likely one of the youngest events in the sequence of formation of cave sediments of the studied caves, the 230Th/234U ages of three samples (79.7±2.3, 104.0±2.9, and 180.0±6.3 ka) are the oldest so far obtained for CCC in Central Europe. This is the first description of CCC formation in one cave during two glacial periods (Saalian and Weichselian). [ABSTRACT FROM AUTHOR]

Two speleothems from the Demänova Cave of Liberty, located in the Low Tatras in Slovakia, were studied in detail. Age-depth modelling based on U-series dating allowed us to constrain the growth period for both speleothems to between approximately 375 and 157 ka. Based on a multiproxy approach, it was possible to identify periods with dominant warm climatic conditions, which enabled long and continuous speleothem growth during most of the marine isotope stage (MIS) 9 and in MIS 7c. Unfavourable for speleothem growth climate included glacial conditions, such as in MIS 10 or MIS 8, and periods connected with diminished rainfall or lower temperature such as in MIS 9b, MIS 7e or MIS 7b. The growth interruptions of the speleothems are related to maximum glacial episodes like in MIS 10a and late MIS 6, or were connected with a decrease in rainfall in MIS 9a and cold, harsh climate conditions in MIS 7d. The obtained records suggest relatively mild glacial periods (MIS 8 and MIS 10) and warm interglacial periods (MIS 9 and MIS 7) enabling long periods of speleothem growth. Gathered results indicate a large diversity of climate conditions during MIS 7, with atypical MIS 7d major stadial occurring within the interglacial complex. Compared records also showed the important role of local factors and changes in the alimentation area, which affected the isotopic composition of speleothem and may cause significant differences in the isotope records from the same cave system, especially during intense climate changes. • A history of climatic changes from two Low Tatras speleothems. • Stable isotope and trace element records covering the MIS 11a – MIS 6c period. • The climate conditions of MIS 10, MIS 8 and MIS 6 enable speleothem growth. • A large diversity of paleoclimate conditions during MIS 7 was recorded in speleothem. [ABSTRACT FROM AUTHOR]

The U-series dating indicates five episodes of flowstone growth in Brestovská Cave, namely: ca. 200 ka, ca. 128-88 ka, ca. 82-65 ka, ca. 64-50 ka, and during the Holocene. The age of flowstones and their spatial distribution within the cave prove that the upper storey of the cave was dewatered before 200 ka. At that time the lower storey also existed and was able to carry the whole water flowing through the cave. It suggests that 200 ka ago the water-table was at similar level as it is at present. Hence, one should accept that the valley bottom was then also at the present level. During at least a part of the MIS 6 the growth of speleothems was possible in the cave. It suggests that the cave was located outside the permafrost zone then. Between 50 ka and Holocene, Brestovská Cave was flooded by invasion waters originating from the melting of the Würm glacier; the water-table was additionally raised due to the blockage of a resurgence by glacifluvial sediments. The flooding event caused the destruction of older deposits, including speleothems, and deposition of fine-grained clastics on the cave walls. [ABSTRACT FROM AUTHOR]

The paper deals with the black coloured laminae which occur within speleothems in Domica cave (Slovakia). The laminae are composed of non completely carbonized organic compounds and charcoal particles. The components were formed during combustion of plant material, mainly wood, inside the cave. Thus, they are a by-product of human activity inside the cave. The radiocarbon ages of organic fraction of these laminae fall between 6460 and 6640 cal BP and 7160 and 7330 cal BP. These dates indicate that the origin of the laminae is connected with two episodes of prehistoric occupation of the cave. The first one should be related either to later part of Gemer Linear Pottery or to early Buick culture populations. The second episode refers to the youngest phase of human occupation in Domica cave reflecting the last period of Bükk populations' existence in the Slovak Karst. [ABSTRACT FROM AUTHOR]

The Ochtiná Aragonite Cave (Western Carpathians) represents a unique natural phenomenon. It originated under particular lithological and hydrogeological conditions of the Ochtiná Karst in which several isolated lenses of Paleozoic crystalline limestone, partly metasomatically altered to ankerite, are enclosed by phyllites. Meteoric water seepage through non-carbonate rocks dissolved limestone and caused the oxidation of ankerite to Fe oxyhydroxides. Carbon dioxide produced during ankerite oxidation enhanced limestone dissolution. The maze cave consists of parallel fault-controlled linear passages and chambers interconnected by transverse horizontal passages. Phreatic and epiphreatic solution morphologies resulted from slowly moving or standing water. These include flat ceilings (Laugdecken), facets, lateral notches, convection ceiling cupola-shaped depressions, and spongework-like hollows. Flat ceilings were developed in several altitude positions, each of them probably closely below the slightly oscillated water table. Primary phreatic cupola-shaped depressions, truncated by flat ceilings, represent relics of the oldest cavities (pre-Quaternary? to Early Pleistocene). Inward-sloping smooth facets were not developed only in passages with flat ceilings, but also in the passages and halls with a vaulted ceiling. The asymmetrical shape of cusped depressions above the facets were documented in detail by a high-resolution cave topography with terrestrial laser scanning and digital photogrammetry. Middle--Late Pleistocene accumulation phases, identified by magnetostratigraphy of cave sediments and U-series dating of speleothems, are associated with phreatic and later epiphreatic development. The deposition on the bottom bedrock began before 1.8 Ma. The Brunhes/Matuyama boundary (0.773 Ma) and Jaramillo magnetozone (0.990-1.071 Ma) were recorded in the profile in the Oválna chodba Passage. Slow depositional rate (~0.09 cm/kyr) calculated from magnetostratigraphy resulted from slow water movement in confined conditions in marbles completely enclosed by phyllites and no direct relation to the surface. Only occasionally turbid water was loaded in extremely fine-grained infiltration material and autochthonous Fe oxyhydroxides. The depositional rate in Mn-rich layer was much slower (~0.03 cm/kyr). Additional U-series dating confirmed that old aragonite generations (with ages about 500-450 ka and 143-121 ka) were partly corroded by repeated floods during Late Pleistocene humid episodes. Aragonite younger than 13.5 ka is not corroded. [ABSTRACT FROM AUTHOR]

Abstract The trans-boundary Slovak-Hungarian Domica–Baradla cave system (Slovak and Aggtelek karsts), >26 km in length, consists of evolution levels that have been formed in relation to the incision phases of the Jósva Valley. Existing opinions on the age of the well-known cave system have not been based on the dating of cave sediments deposited during older evolution phases. Previous U-series dating and the first paleomagnetic analyses of dripstones, flowstones and fine-grained allochthonous sediments identified only younger accumulative phases of the cave evolution in Late Pleistocene. Our cosmogenic nuclide dating (10Be and 26Al) of allochthonous fluvial gravels from the upper and lower levels of the Domica Cave (Slovakia) reveal much older evolution phases. Two burial ages at 3.47 ± 0.78 Ma and 2.94 ± 0.50 Ma show that the upper level of the cave system originated in, or before, the Middle Pliocene. Its younger accumulation phases (Early–Middle Pleistocene) are documented based on magnetostratigraphy and U-series dating of fine-grained sediments and flowstones. The Brunhes/Matuyama boundary (780 ka), Kamikatsura excursion (~900 ka), Santa Rosa excursion (~932 ka) and Jaramillo magnetozone (~1.001–1.069 Ma) were identified from the newly studied profile in the Suchá chodba Passage (the ages of flowstones in upper part of this profile are ~130 ka, 173 ka and 199 ka). In some places, several small older (paleokarst?) solutional phreatic cavities are cut by this cave level. The lower evolution level, located 12–18 m below the upper level, originated in the Early Pleistocene (the burial age of allochthonous fluvial gravels is 1.92 ± 0.25 Ma). Low pre-burial denudation rates (3.1–5.6 m/Ma) correspond with the slowdown or interruption of tectonic uplift of the area and the long-term stabilized erosion base level during the formation of these cave levels. Their origin was linked with the formation of large pediments, of which remnants are preserved on both sides of the Jósva Valley (Hungary). The pediments probably correlate to the 'foothill' (Middle Pliocene) and 'river-side' (Late Pliocene–Early Pleistocene) levels in the denudation chronology of the Western Carpathians. Highlights • Fluvially-modelled cave levels developed in relation to the formation of large pediments. • Combined use of absolute dating methods for the reconstruction of cave chronology. • The largest cave levels in the marginal part of the Western Carpathians formed in the Middle Pliocene and Early Pleistocene. • Paleo-denudation rates during the formation of cave levels are equivalent to low denudation rates of old cratons. • Refined denudation chronology of the Western Carpathians during the Middle Pliocene. [ABSTRACT FROM AUTHOR]