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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]

Abstract The direct dating of pre- and postfaulting dislocated calcite speleothems afforded new insight into slope failure in the Tatra Mountains in southern Poland. A multi-approach study of the karstic Kalacka Cave (non-crevasse type) enabled us to infer the slope deformation structure, which had been poorly preserved in ground surface topography, using combined methods including geomorphological and structural mapping of cave and ground surfaces, paleostress analysis, near-surface electrical resistivity tomography (ERT) and induced polarization methods (IP), uranium series dating (234U/230Th), calcite microtexture analysis, and stable isotope (δ18O and δ13C) analysis. Here, slope deformation began with dilation between 280 ± 7 ka and 265 ± 8 ka and proceeded as deep-seated gravitational slope deformations. The final stage consisted of dilation rejuvenation and rockfall during the latest Pleistocene or Holocene (post 35 ± 4 ka). Additionally, some dilations are evident beyond the extent of the landslide detected by ERT, indicating further progradation of slope failure. Since this failure was initiated during the climatic transition from MIS 9 to MIS 8, stable isotope analysis of calcite flowstone layers was applied to test climate factors. The correlation of calcite microtexture and δ18O and δ13C compositional changes with the interval of dilation activity indicates that regional environment factors, chiefly an increase in precipitation, probably contributed to slope destabilization. Highlights • A previously unknown relict landslide was identified. • Dilation in speleothems was directly dated. • Three phases of landslide evolution were identified. • Stable isotope analysis implied an precipitation increase as a reason for slope failure. [ABSTRACT FROM AUTHOR]

The Houping Tiankeng cluster is a part of the South China Karst UNESCO World Natural Heritage Site. Within the distinctive Wulong plateau-gorge karst, > 200 km of cave passages have been documented to date. This paper focuses on detailed tectonic and morphological research on the Luo Shui Kong cave, enriched with U-series dating of speleothems and complemented by morphometric analysis of the San Wang Dong and Er Wang Dong caves. All of these caves exhibit three regional levels of cave development: 1) 1040–1020 m a.s.l.; 2) 900–840 m a.s.l.; and 3) 740–660 m a.s.l. The Houping Tiankeng area is a carbonate rock sequence several hundred meters thick, overlain by the less soluble Lower Ordovician strata, limiting recharge points to faults exposing underlying easily soluble formations. This leads to the domination of concentrated, high-volume inflow and thus results in caves of large volume in the plateau-gorge karst. Shafts connecting the surface with cave passages located underneath formed along faults, changing the hydrogeological pattern through karst water capture and remodeling of existing conduits, albeit mainly by increasing their overall dimensions rather than by deepening them. The most favorable structures for cave-level development are two sets of joints conjugated with gently inclined bedding. Since these joints are characterized by a small vertical extent, downward development is limited. Hence, most of the passages are wide but not deep canyons and typical of a water-table cave pattern. Places where the fault plane is eroded from the surface and where, at the same time, an underneath cave chamber ceiling expands upwards are particularly predisposed to the formation of a tiankeng. [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]

Caves are important markers of surface evolution, since they are, as a general rule, linked with ancient valley bottoms by their springs. However, caves can only be dated indirectly by means of the sediments they contain. If the sediment is older than common dating methods, one has to use multiple dating approaches in order to get meaningful results. U/Th dating, palaeomagnetic analysis of flowstone and sediment profiles, cosmogenic dating of quartz pebbles, and mammalian dating allowed a robust estimate of speleogenesis, sediment deposition, climatic change at the surface, and uplift history on the Periadriatic fault line during the Plio-Pleistocene. Our dates indicate that Snežna jama was formed in the (Upper) Miocene, received its sedimentary deposits during the Pliocene in a rather low-lying, hilly landscape, and became inactive due to uplift along the Periadriatic and Sava faults and climatic changes at the beginning of the Quaternary. Although it is only a single cave, the information contained within it makes it an important site of the Southern Alps. [ABSTRACT FROM AUTHOR]