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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. publishedVersion

International audience; 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 Josva 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 (Be-10 and Al-26) 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 (similar to 900 ka), Santa Rosa excursion (similar to 932 ka) and Jaramillo magnetozone (similar to 1.001-1.069 Ma) were identified from the newly studied profile in the Sucha chodba Passage (the ages of flowstones in upper part of this profile are similar to 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 Josva 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.

Constructional caves in freshwater limestone appear to be the least described of the most commonly occurring types of cave. They are also known under the names “primary”, “syngenetic” or “framework” caves. Such caves develop in tufa and travertine during the growth of their host rock. Two main genetic categories of constructional caves have been recognized, described herein as progradational and aggradational. Progradational caves develop chiefly in tufa, less commonly in travertine, as the result of progradation occurring on a steep depositional surface. An empty void is often left between an older surface and a new carbonate mass growing outwards from it as a vertical or inclined curtain. The size and shape of a progradational cave depend on: (i) energy of water over the steep section, (ii) height of the steep section, (iii) shape of the depositional surface, (iv) water chemistry. The category of progradational caves includes also caves roofed by bridges of travertine or tufa. Progradational caves are richly decorated with speleothems like those seen in other limestone caves. The growth of the speleothems is facilitated by efficient percolation of water through the cave ceilings of carbonate with high effective porosity. Clastic sediments may accumulate in relict progradational caves, and often contain palaeontological, archaeological and palaeoanthropological finds. Aggradational caves may develop within freshwater carbonate (predominantly travertine) buildups at the outlets of artesian springs where the orifice lips constantly migrate upward. An active aggradational cave acts as a feeder channel for such a spring, so it is filled with water. The sizes and shapes of aggradational caves depend upon: (i) the nature of bedrock beneath travertine, (ii) local hydrological situation which controls the position of the piezometric surface, (iii) topography around the spring orifice, (iv) chemistry of water, and (v) evolution of the above conditions during the buildup growth. In addition to progradational and aggradational caves, tree-mould caves and cavities created by the subrosion of active carbonate buildups develop during their host carbonate growth. The majority of known constructional caves are of Quaternary, predominantly Holocene, age. This article is a review of constructional caves based on the available literature.

Multiphase cave conduit offset and related speleothem damage in the Demanova Cave System (DCS; the Low Tatra Mts, Central Western Carpathians) were dated with U-series methods, revealing five events: (1) 570 (442)–417 ka, (2) 306–291 ka, (3) 184–130 ka, (4) ~19 ka, and (5) 2.56–2.3 ka. To decipher the cause of the damage, we combined geochronological data with structural, geomorphological, and seismological research. Gravity sliding as a probable source of damage is unlikely since the Demanova Valley has deepened only to a small extent for the past 550 ka and the steep fissure guiding the studied parts of the DCS extends below the recent valley. However, coseismic block sliding cannot be unambiguously excluded, as Newmark displacement analysis revealed that any >M7 earthquake in the 25 km range could have produced a 10-cm pseudostatic displacement. The studied offsets were accompanied by shaking, as inferred from fallen stalagmites and stalactites; hence, distant earthquakes are plausible damage sources. We applied ground-motion models and compared them with seismicity and scant prehistoric and historical data to identify and quantify the probable seismic source, which is most likely the Sub-Tatric Fault located 17.5 km from the cave. As inferred from the applied ground-motion models, a > M7 event on the Sub-Tatric Fault would generate a PGA >4 m/s2 in the cave despite the attenuation, which is above the threshold horizontal ground acceleration forcing the majority of speleothems to break. Although the mechanism that leads to cave passage offsets remains unclear we consider them as an off-fault damage caused by secondary faulting related to postseismic surface vertical movements, or less likely but not out of the realm of possibility distributed rupturing.

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.

The aim of the contribution is to demonstrate the usefulness of the cave passage pattern analysis for neotectonics in suitable regions. The principal presumption is that the orientation of cave passages is perpendicular to the horizontal minimum stress (Shmin). The comparison of the obtained data with the neotectonic structures and the orientation of the Pliocene – Quaternary principal stress field (Shmin) is presented. The back-arc extension dominated in the Western Carpathians during the Pliocene–Early Pleistocene. The orogen-parallel extension has been determined for central part of the Western Carpathians (Slovakia) for the Late Pleistocene–Holocene. The results revealed a link between the passage patterns of the Western Carpathian caves and orientation of the principal extension obtained from structural data.

The EU-TecNet monitoring network uses customized three-dimensional extensometers to record transient deformations across individual faults. This paper presents the first results from two newly established monitoring points in the Balkan Mountains in Bulgaria. The data from Saeva Dupka, recorded across an EEN-WWS striking fault, show sinistral strike-slip along the fault and subsidence of the southern block. Much of the subsidence occurred around the time of the distal MW = 5.6 Pernik Earthquake. An important transient deformation event, which began in autumn 2012, was reflected by significant compression and following extension, across the monitored fault. The data from Bacho Kiro, recorded across a NE–SW striking fault, show sinistral strike-slip along the fault and subsidence of the north-western block. The same important deformation event was reflected by changes in the strike-slip, dip-slip, and horizontal opening/closing trends. These results have been compared to data from other monitoring points in the Western Carpathians, External Dinarides, and Tian Shan. Many of the sites show evidence of simultaneous displacement anomalies and this observation is interpreted as a reflection of the plate-wide propagation of a tectonic pressure pulse towards the end of 2012.

Ice caves feature various morphologies of ice surfaces in several scales. The gross morphology of cave ice blocks or other bodies depends on a cave’s morphology and morphometry, as well as sources and volume of ice. Several long-lasting and ephemeral forms originated on ice surfaces, mostly in caves with perennial ice fill. Long-lasting forms consist of supraglacial ice-deposited, ablation and compounded ice-deposited/ablation forms and more or less sporadic intraglacial and subglacial ablation forms. Intraglacial ablation forms are also deepened into ice walls and ceilings of artificial tunnels excavated trough an ice monolith in some show caves. Several ablation forms are similar or identical to those forms in glacier caves, i.e., ablation caves in glaciers. The ephemeral supraglacial ice-deposited and ablation forms in ice cave are observed seasonally during and after phases of intense seepage of rainfalls or snow-melting waters into the cave through overlying fractured and karstified limestone beds with a high permeability (mostly in temperate zones with a seasonal climate regime). Compared with cave bedrock morphology, the surface morphology of ice fill is dynamic and changed, first and foremost, in smaller sizes. In some cases, ice morphologies were modified or formed due to human impact in relation to show cave development for tourism or the speleological exploration of caves.

Ice caves belong to the significant natural phenomena in Slovakia. They occur mainly in mid- and high-mountain areas, and several of them are filled by ice only seasonally (during the winter season to the summer). Based on existing data, 45 caves are permanently filled with ice. The well-known Dobsinska ľadova jaskyňa Cave (Dobsina Ice Cave) presents a typical descending sack-like cavity with the largest ice volume in the world (despite the fact that it is located in the mid-mountain position, below 1000 m a.s.l.). Its ice body is an important natural archive with paleoclimatic evidence of approximately the past 1000 years. The Silicka ľadnica Cave (Silica Ice Cave) is the lowest situated perennial ice cave, up to a 50 degrees north latitude, in the temperate climate zone. Both caves (together with the Snežna diera Cave) are included in the World Heritage List within the Slovak-Hungarian site named Caves of Aggtelek and Slovak Karst. Two ice caves (Dobsinska ľadova jaskyňa Cave and Demanovska ľadova jaskyňa Cave) are open to the public. The Dobsina Ice Cave is one of the first electrically illuminated show caves in the world. But the development of both caves for tourism has resulted in some negative human impacts. At present, the caves are used as educational localities under the supervision of the State Nature Conservancy of the Slovak Republic. All caves in Slovakia are protected as natural monuments (the most significant caves as national natural monuments, including several ice caves).

During the Alpine orogeny of the Western Carpathians, hypogene caves have originated in different settings and epochs. Several caves of hydrothermal origin in crystalline limestones and metasomatic secondary quartzites (metasomatic silicites) are known in the central zone of the Stiavnica stratovolcano, Stiavnicke vrchy Mountains. The early phases of speleogenesis in the crystalline limestone near Sklene Teplice Spa were caused by post-magmatic dissolution linked either to the emplacement of subvolcanic granodiorite intrusions during Late Badenian time or to the spatially associated Late Sarmatian epithermal system. Speleogenesis in metasomatic secondary quartzites in the Sobov quarry is related to deep-seated hydrothermal processes associated with a diorite intrusion in the northern part of the central zone of the Stiavnica stratovolcano during its pre-caldera evolution phase in Upper Badenian. Unusual caves in metasomatic magnesite, with mineralogical evidences of their hydrothermal origin, were investigated in the Revucka vrchovina Mountains. Paleokarst geoda-like cavities and small hydrothermal caves occur in nappe structures of Triassic carbonates that were uplifted within the Tatra-Fatra belt of core mountains (many of these cavities are integrated into younger and larger non-hypogene caves). Cavities with thermal water in underlying and faulted Mesozoic carbonates (covered by Neogene or Paleogene sedimentary rocks) were identified by boreholes in some intermontane basins (Rimavska kotlina Basin, Liptovska kotlina Basin). A phreatic shaft formed by progradational collapse of non-carbonate beds disrupted by artesian karstification of underlying carbonates occurs at Tornaľa Town in the Rimavska kotlina Basin. Several caves with hypogene morphologies have originated along marginal faults of horst structures or fault edges of horst–graben structures (speleogenesis by thermal or slightly heated ascending waters, but mineralogical evidences of hydrothermal karstification were not found).

This study deals with the possibilities of expertdrivensemi-automated recognition of planation surfacesand other flat landforms in the area of the Aggtelek Karst,Hungary. Planation surfaces are the most debatable andvague landforms and can be defined as parts of terrainformed by long-lasting erosion-denudation processes underthe stagnant erosion base conditions. In terms of denudationchronology they can be considered as morphologicalindicators of different evolution stages of area. Inkarst areas planation surfaces and river terraces are mostlycorrelated with cave levels, which originated in relation tothe same stagnant erosion base. Because there is no generalmethod of delineation of planation surfaces, the mainobjective of the study was to find a suitable method forsemi-automated recognition of flat landforms in the AggtelekKarst, which should correspond to different phasesof the Jósva River incision and therefore could be correlatedto the multilevel cave system of the study area.Several methods for semi-automated landform classificationwere tested for recognition of flat surfaces in a relativelyobjective way. Slope gradient thresholding tool, andr.param.scale and r.geomorphon modules implemented inGRASS GIS were tested. As a result, the r.geomorphonmodule was proven as the most suitable method for delineationof relatively flat surfaces. Findings of the presentedwork can be used as a morphological indicator ofthe comprehensive reconstruction of evolution of the AggtelekKarst and the Slovak Karst.

The chemical composition of water samples was studied from different caves in Slovakia. The water samples were collected from caves of two karst regions: (1) the Demanovský Cave System (DCS), situated in the Low Tatra Mountains (Northern Slovakia), which is mainly formed of limestone and dolomites; and (2) the Slovakian Karst to the Southeast is formed of limestone. A considerable difference between water from the two regions was shown. The waters from the DCS, that were controlled by vadose water percolating through different types of host rocks, contained more Mg ions than those from the Slovakian Karst caves whereas, the concentration of SO4 was controlled by the dissolution of displacive gypsum and/or oxidation of pyrite. The distribution of NO3 in the studied samples was random, hence nitrates probably derived from few pollution sources. The total mineralization of the water was covariant with calcite and aragonite saturation indices. In general, both parameters are higher in the Slovakian Karst caves than in the DCS. It is controlled probably by differences in climatic conditions, soil and plant covers between these two regions. The main goal of this article is to characterize the major-ion water chemistry within the studied caves as well as some microelements. The results have confirmed the dominant role of the bedrock petrography in forming the general chemistry of cave waters.

In addition to the morphostructures and climatic conditions, landform ­evolution on the territory of Slovakia has been heavily influenced by the history of human settlement. Human impact on geomorphic processes has a longer history in the sub-Carpathian lowlands (embracing millennia) than in the Carpathian mountains (measured in centuries). In addition to the predominant gravitational processes (first of all landslides), major natural exogenic geomorphic agents in Slovakia include fluvial processes, soil erosion by water, karst and pseudokarst evolution, aeolian, cryogenic and nival actions. The slopes of agricultural areas were completely remodeled by tillage and water erosion processes. Increased frequency of extreme meteorological-hydrological events during the Little Ice Age resulted in enormous activation of gullying, floods and other precipitation-induced processes. Drastic terrain adjustments, including the levelling of terraced plots, were done due to collectivization in agriculture. The predicted climate change could contribute to an increase in natural ­hazards, particularly those related to precipitation extremes (floods and landslides).

Age of Black Coloured Laminae Within Speleothems from Domica Cave and Its Significance for Dating of Prehistoric Human Settlement 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 Bükk 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.