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Caves are unique sedimentary archives that may record the evolution of the surrounding landscape. In this study, we applied combination of mineralogical data on allochthonous sediments with digital modelling of isobase surfaces to reconstruct the multi‐phased geomorphological development of the karst of the Harmanecká dolina Valley. The allochthonous cave sediments contain quartz and translucent heavy minerals (HMs) such as tourmaline, garnet, rutile, apatite, zircon, pyroxene, amphibole, staurolite, spinel, monazite, corundum, epidote, xenotime and florencite. Rounded shape and surface microtextures preserved on quartz and most HM grains point to predominantly a fluvial transport of detritus and its multiple recycling history. Pyroxene and amphibole are exceptions that denoted a very close source and the first‐cycle sedimentation from the adjacent volcanic Kremnické vrchy Mts. corresponding to obtained SHRIMP U–Pb detrital zircon ages of ~13.8–12.8 Ma. Heavy‐mineral geochemistry (e.g., zoned grossular‐rich garnet) and wide range of the Palaeozoic ages (Ordovician to Permian) confirms that the studied detritus sourced dominantly in the Western‐Carpathian crystalline basement rocks of the Veporic/Tatric tectonic units initially distributed by the palaeo‐Hron River and its tributaries from the east. Rare cummingtonite, remarkable tourmaline with omphacite inclusions and florencite point to the mixture of recycled sediments of Neogene Danube Basin formations containing also Austroalpine pre‐Neogene basement detritus, and confirm the original widespread distribution of the Neogene sediments currently eroded. Geomorphometric analyses of a LiDAR digital terrain model and derived isobase surface elevation models indicate the topographic development of wider area and support the findings about the transport direction of detritus. Presented multi‐method approach is suitable not only for the understanding of development of the surroundings of Harmanecká dolina Valley but also for the palaeogeographic and geomorphological reconstructions of similar karst and non‐karst areas. [ABSTRACT FROM AUTHOR]

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.

Dobšiná Ice Cave has attracted the attention of many researchers since its discovery more than 150 years ago. Although the cave is located outside the high-mountain area, it hosts one of the largest blocks of underground perennial ice. The topographic mapping of this unique UNESCO Natural Heritage site has led to several historical surveys. In the last decades of rapid climate change, this natural formation has been subject to rapid changes that are dynamically affecting the shape of the ice body. Not only increased precipitation, the rise in year-round surface temperatures, but also the gravity cause significant shape changes in the ice filling. This paper describes modern technological tools to comprehensively survey and evaluate interannual changes in both the floor and wall of the underground ice block. Technologies such as digital photogrammetry, in conjunction with precise digital tacheometry, make it possible to detect ice accumulation and loss, including the effect of sublimation due to airflow, as well as sliding movements of the ice block to the lower part of the cave. In the last two years, geophysical methods (microgravimetry and ground penetrating radar) have been added to determine the thickness of the floor ice in the upper parts of the cave due to the complexity of the measurements. The paper not only highlights the current technological possibilities but also points out the limitations of these technologies and then sets out solutions with a proposal of technological procedures for obtaining accurate geodetic and geophysical data. [ABSTRACT FROM AUTHOR]

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 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]

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]

The Večerná-Čárka cave system is the longest underground site of the Kuchyňa-Orešany Karst (Malé Karpaty Mountains, western Slovakia). Although its length is only 58 m, it is a site of remarkable interest in terms of speleogenesis that was strongly controlled by tectonic structure of the Middle Triassic limestone (Fatric Unit). Morphologically, the studied cave system represents a branched cave, formed by linear, and in some places intersecting passages. Their direction is strongly linked with two systems of steep parallel and crossing tectonic failures of N–S and NW–SE direction. Phreatic morphologies of passages show that the cave system originated by dissolution of limestone along these tectonic discontinuities, in several places the cave passages were enlarged by the destruction of parallel rock partitions. Probably, waters of deeper circulation ascended along steep tectonic fractures. Since these waters were relatively saturated, limestone mostly dissolved in the zone of mixing with seeping rainwater. A dense network of steep parallel and intersecting tectonic fractures allowed to diffuse groundwater circulation without much concentration of water flow into one or more main conduits. The absence of water table notches, ceiling cupolas as well as blind oval chimneys indicate that the caves formed below or just below the former piezometric surface of groundwater and without its significant oscillations, e.g. in the shallow phreatic zone. The estimated Pliocene (or late Pliocene?) age of the cave system (lying at an altitude of 413–419 m asl.) is determined based on its location above the recent hydrographic network (60 m above the floor of the valley) and by the remains of the Plio-Pleistocene planation surface located at 250–350 m asl. in the adjacent part of the Malé Karpaty Mountains. [ABSTRACT FROM AUTHOR]

The Moldavská jaskyňa Cave is the largest and most typical two-dimensional underground labyrinth in Slovakia. It was formed in Wetterstein Limestones, mainly due to the diffuse penetration and repeated flood injections of allochthonous waters from the Bodva River, and persistent ponded floodwaters in underground conduits. In relation to the uneven fracturation pattern in limestones, the cave is composed from an angular network and anastomotic-like, locally spongework segments. The former is predisposed on distinctive fractures, while the latter are predisposed mainly on less distinctive, small-scale discontinuities. Same as passages and halls of the cave labyrinth, small-scale phreatic and epiphreatic solution morphologies on the ceiling and walls (ceiling pockets, spongework cavities, paragenetic ceiling channels, rock pendants and partitions, inward-inclined facets, flat ceiling surfaces, water-table notches and some other forms) were sculpted in slowly flowing to stagnant waters. The bedrock floor is not visible in the whole cave, because it is covered by thick fine-grained allochthonous sediments (slackwater facies), in many places up to the ceiling. The Moldavská jaskyňa originated in the Late Pleistocene and Holocene, during several phases of erosion and accumulation in relation to the downcutting and aggradation of the Bodva river bed, lateral planation of the floodplain, and associated oscillations and stagnations of groundwater table, as well as repeated floods of underground passages and halls. [ABSTRACT FROM AUTHOR]

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