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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That network cave pattern is a type of maze cave characterized by a complex pattern of repeatedly connected passages in a cave system. in map view, this type of maze cave appears similar to a city street map. it is typically formed by solutionally aggressive water infiltrating through fractures in an overlying insoluble cap-rock thus exhibiting a jointcontrolled pattern. synonym: labyrinth.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for cave level (Keyword) returned 66 results for the whole karstbase:
Showing 31 to 45 of 66
Eis- und Lufttemperaturmessungen im Schnberg-Hhlensystem (1626/300) und Modellvorstellungen ber den Eiszyklus, 2008, Wimmer, M.
Currently 34 entrances to the Schnberg- Hhlensystem are known, giving rise to a complex air ventilation pattern. Ice is present in some near-surface parts of the cave and its volume and geometry varies significantly. A significant reduction of ice was observed between 1970 und 2002, and hitherto unknown entrances were released by the melting process. Measurements of ice profiles started in 1994 and the air temperature has been logged since 1995. These data showed that pits of the Raucherkarhhle extending to high altitude and connections to the Feuertal-Hhlensystem are responsible for the main supply with cold air. The presence of ice is subject to medium- to long-term variations depending on the changing circulation of air between the different cave levels which themselves are forced by the periodic opening and closing of pits by near-surface ice. In stark contrast to the current trend of atmospheric warming in the Alps the cave has been experiencing gradual cooling during the past years. Pits critical for cold air supply are currently open and cold winter air can reach the level of the Kleiner Rundgang, wherethe ice started to grow following an ice-free period. In the Eisstadion, the temperature is currently falling and the ice also began to grow after a long-lasting melting period due to positive year-around. A model is presented in which the apparently cyclic opening and closing of entrances control the complex ventilation pattern and hence the high extent of ice dynamics in this cave between 1965 to 2007.

Cryogenic cave carbonates from the Cold Wind Cave, Nzke Tatry Mountains, Slovakia: Extending the age range of cryogenic cave carbonate formation to the Saalian, 2009, k K. , Hercman H. , Orvoov M. , Ja?kov I.
Cold Wind Cave, located at elevations ranging between 1,600 and 1,700 m a. s. l. in the main range of the Nzke 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 Nzke 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 (?13C: 0.72 to 6.34 , ?18O: 22.61 to 13.68 V-PDB) and the negative relation between ?13C and ?18O, 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 (79.72.3, 104.02.9, and 180.06.3 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).

Constraints on alpine speleogenesis from cave morphology - A case study from the eastern Totes Gebirge (Northern Calcareous Alps, Austria), 2009, Plan Lukas, Filipponi Marco, Behm Michael, Seebacherd Robert, Jeutter Peter

The Totes Gebirge is the largest karst massif in the Northern Calcareous Alps (NCA). This paper focuses on the eastern part, where two major multiphase alpine cave systems (Burgunderschacht Cave System and DÖF–Sonnenleiter Cave System) are described with respect to morphology, hydrology, and sediments. The caves consist of Upper Miocene galleries of (epi)phreatic genesis and younger vadose canyon-shaft systems. Morphometrical analyses were used to determine the relevance of (1) cave levels (horizontal accumulations of galleries), (2) slightly inclined palaeo water tables of speleogenetic phases, (3) initial fissures, and (4) inception horizons on the development of the cave systems. (Epi)phreatic cave conduits developed preferentially along vertical faults and along only a restricted number of bedding planes, which conforms to the inception horizon hypothesis. For at least one of the systems, a development under epiphreatic conditions is certain and a hydrological behaviour in the “filling overflow manner” is likely.

Observations in further major cave systems in the Totes Gebirge identify palaeo water tables of speleogenetic phases that show inclinations of 1.5° ± 1°. Analyses of cave levels reveal distinct peaks for each cave but it is hardly possible to correlate these elevation levels between caves of different parts of the karst massif. Therefore, we conclude that cave levels (strictly horizontal) indicate speleogenetic phases or palaeo water tables respectively, but they cannot be correlated with palaeo base levels or on regional scale. An exact correlation between cave development and palaeo base levels at the surface is only possible with inclined palaeo water tables of speleogenetic phases.

For the Totes Gebirge, the inclination directions of the speleogenetic phases imply that palaeo drainage was radial and recharge was autogenic, which is in contrast to observations from other plateaus in the NCA. Differences in fracture properties seem to be the reason for the development of divergent types, according to the Four State Model. A simplified model for cave genesis and surface development in this area since the Upper Miocene is presented.


Cryogenic cave carbonates from the Cold Wind Cave, Nzke Tatry Mountains, Slovakia: Extending the age range of cryogenic cave carbonate formation to the Saalian, 2009, k K. , Hercman H. , Orvoov M. , Jač, Kov I.

Cold Wind Cave, located at elevations ranging between 1,600 and 1,700 m a. s. l. in the main range of the NÃzke 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 NÃzke 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).


Young uplift in the non-glaciated parts of the Eastern Alps, 2010, Wagner T. , Fabel D. , Fiebig M. , Hä, Uselmann Ph. , Sahy D. , Xu S. , Stü, We K.

We report the first incision rates derived from burial ages of cave sediments from the Mur river catchment at the eastern margin of the Eastern Alps. At the transition zone between the Alpine orogen and the Pannonian basin, this river passes through the Paleozoic of Graz — a region of karstifiable rocks called the Central Styrian Karst. This river dissects the study area in a north–south direction and has left behind an abundance of caves. These caves can be grouped into several distinct levels according to their elevation above the present fluvial base level. Age estimates of abandoned cave levels are constrained by dating fluvial sediments washed into caves during the waning stages of speleogenesis with the terrestrial cosmogenic nuclide method. These ages and the elevations of the cave levels relative to the current valley floor are used to infer a very complex history of 4 million years of water table position, influenced by the entrenchment and aggradation of the Mur river. We observe rather low rates of bedrock incision over the last 4 Ma (in the order of 0.1 mm/y) with an e-folding decrease in this trend to lower rates at younger times. We relate this incision history to a tectonic setting where an increase of drainage area of the Mur river due to stream piracy in Late Miocene to Pliocene times is linked to surface uplift. The later decrease in valley lowering rates is attributed to the rise of the base level related to aggradation of sediments within the valley. Sediment transport through the valley from the upstream section of the Mur river limited the erosional potential of the river to a transport limited state at the later stages of the incision history.


Geomorphologische Untersuchung und genetische Interpretation der Dachstein- Mammuthhle (sterreich), 2010, Plan L. , Xaver A.
The speleogenesis of Dachstein-Mammuthhle, the third-longest cave system in the Northern Calcareous Alps, has been discussed controversially in the past. Using morphologic mapping and morphometric data of the central parts of the cave in combination with modern speleogenetic models a re-evaluation of its development is attempted. The geometry of the cave and several small-scale features (e.g., scallops, karren, ceiling meanders), which date back to the early history of the cave formation, lead to the following interpretion: old phreatic parts (galleries, mazes, and some pits) developed under epiphreatic conditions during flood events, followed by younger, vadose canyon-shaft-systems. Scallops and sedimentary structures indicate a general westward flow direction. Sediments played an important role during the formation of the profiles, i.e. the profiles expanded upward (paragenesis) because the floor of the galleries was sealed by sediments, and only part of the cross section, as it can be seen today after removal of these sediments, was occupied by water. This is relevant for calculations of the palaeodischarge from mean scallop lengths and cross-section areas. Paragenesis can only be ruled out for the origin of the keyhole profile of the so-called Canyon (near the Westeingang) and the palaeodischarge was estimated to 16 m/s. This, however, was probably only a fraction of the total discharge of this system as several additional large galleries occur at the same cave level. The former catchment area was probably located south of todays Northern Calcareous Alps

Estimating the Timing of Cave Level Development with GIS, 2011, Jacoby B. S. , Peterson E. W. , Dogwiler T. , Kostelnick J C.

Identifying cave levels provides insight into cave development and climatic changes that have affected a karst system over time. Cosmogenic dating has been used to interpret levels in Mammoth Cave and the Cumberland Plateau. This absolute dating technique has proven successful in determining cave paleoclimates and regional geomorphic history, but is expensive. The study presented here is a preliminary method to cosmogenic dating that can outline a region’s speleogenesis using a Geographic Information System (GIS) and published denudation rates. The Carter Cave system in northeastern Kentucky is within the karst landscape found along the western edge of the Appalachians and contains multiple daylighted caves at various elevations along valley walls. These characteristics make the Carter Caves an ideal location to apply GIS to cave level identification and evolution as described by Jacoby et al. (in review), who identified the cave levels within the area. The authors concluded that an argument can be made for either four or five cave levels in the Carter Cave system; however, studies identified four levels in both Mammoth Cave and the Cumberland Plateau. Further analysis indicated that the fifth level formed as a result of a change in lithology rather than an event that influenced the local base level. This research is an extension of the conclusions presented by Jacoby et al. (in review). The GIS was used to calculate the volume of surficial material lost within each level as a result of degradational geomorphic processes. Then, level thickness lost and published denudation rates were used to calculate the relative time required to form each level. There was not one denudation rate applicable to each level within the cave system, but the rates varied between 12 m/Ma and 40 m/Ma. This study concludes that the cave system took between 3.4 and 5.7 Ma to form. This study did not perform an absolute dating of cave sediments or assess any detailed stratigraphic influence.


Recent developments on morphometric analysis of karst caves, 2011, Piccini, Leonardo

Nowadays, the use of computers and the digital techniques for survey processing easily allows to carry out morphometric analysis of caves and karst systems. Morphometric indices have been proposed by many authors in order to describe the genetic features of some particular types of caves, such as coastal ones, maze caves or isolated voids. Large cave systems can be analyzed through the reconstruction of a 3D model. The digital model can be used to evaluate the role of the structural setting or the evolution stages through the recognizing of particular levels where epi-phreatic passages are more developed. These levels are particularly significant when a lithological or structural control can be excluded. Some morphometric indices, obtained by the ratios of simple dimension parameters of caves, allow the statistical analysis of large databases, collected in the regional speleological inventories, in the attempt to recognize different geomorphic populations of caves. Further studies and a greater number of analysis could allow to use these morphometric indices to distinguish genetic categories of caves and to get a useful instrument for the study of the evolution of karst areas.


Recent developments on morphometric analysis of karst caves, 2011, Piccini L.

Nowadays, the use of computers and the digital techniques for survey processing easily allows to carry out morphometric analysis of caves and karst systems. Morphometric indices have been proposed by many authors in order to describe the genetic features of some particular types of caves, such as coastal ones, maze caves or isolated voids. Large cave systems can be analyzed through the reconstruction of a 3D model. The digital model can be used to evaluate the role of the structural setting or the evolution stages through the recognizing of particular levels where epi-phreatic passages are more developed. These levels are particularly significant when a lithological or structural control can be excluded. Some morphometric indices, obtained by the ratios of simple dimension parameters of caves, allow the statistical analysis of large databases, collected in the regional speleological inventories, in the attempt to recognize different geomorphic populations of caves. Further studies and a greater number of analysis could allow to use these morphometric indices to distinguish genetic categories of caves and to get a useful instrument for the study of the evolution of karst areas.


Correlations of cave levels, stream terraces and planation surfaces along the River MurTiming of landscape evolution along the eastern margin of the Alps, 2011, Wagner Thomas, Fritz Harald, Stü, We Kurt, Nestroy Othmar, Rodnight Helena, Hellstrom John, Benischke Ralf

The transition zone of the Eastern Alps to the Pannonian Basin provides one of the best sources of information on landscape evolution of the Eastern Alpine mountain range. The region was non-glaciated during the entire Pleistocene. Thus, direct influence of glacial carving as a landscape forming process can be excluded and relics of landforms are preserved that date back to at least the Late Neogene. In this study, we provide a correlation between various planation surfaces across the orogen-basin transition. In particular, we use stream terraces, planation surfaces and cave levels that cover a vertical spread of some 700 m. Our correlation is used to show that both sides of the transition zone uplifted together starting at least about 5 Ma ago. For our correlation we use recently published terrestrial cosmogenic nuclide (TCN) burial ages from cave sediments, new optically stimulated luminescence (OSL) ages of a stream terrace and U–Th ages from speleothems. Minimum age constraints of cave levels from burial ages of cave sediments covering the last ~ 4 Ma are used to place age constraints on surface features by parallelizing cave levels with planation surfaces. The OSL results for the top section of the type locality of the Helfbrunn terrace suggest an Early Würm development (80.5 ± 3.7 to 68.7 ± 4.0 ka). The terrace origin as a penultimate gravel deposit (in classical Alpine terminology Riss) is therefore questioned. U-series speleothem ages from caves nearby indicate formation during Marine Isotope Stages (MIS) 5c and 5a which are both interstadial warm periods. As OSL ages from the terrace also show a time of deposition during MIS 5a ending at the MIS 5/4 transition, this supports the idea of temperate climatic conditions at the time of deposition. In general, tectonic activity is interpreted to be the main driving force for the formation and evolution of these landforms, whilst climate change is suggested to be of minor importance. Obvious hiatuses in Miocene to Pleistocene sediments are related to ongoing erosion and re-excavation of an uplifting and rejuvenating landscape


Identifying the Stream Erosion Potential of Cave Levels in Carter Cave State Resort Park, Kentucky, USA, 2011, Jacoby B. S. , Peterson E. W. , Dogwiler T.

Cave levels, passages found at similar elevations and formed during the same constant stream base level event, reveal information about paleoclimates and karst geomorphology. The investigation presented here examines how Stream Power Index (SPI) relates to cave levels. The study area, Carter Caves State Resort Park (CCSRP), is a fluviokarst system in northeastern Kentucky containing multiple cave levels. SPI determines the erosive power overland flow based on the assumption that flow accumulation and slope are proportional to potential for sediment entrainment. Part of this digital terrain analysis requires the creation of a flow accumulation raster from a digital elevation model (DEM). In creating the flow accumulation raster, one has the option to fill depressions (also considered errors) within the DEM. Filling these depressions, or “sinks,” creates a well-connected stream network; however it also removes possible sinkholes from the DEM. This paper also investigates the effects a filled and an unfilled DEM have on SPI and what each reveals about erosion potential in the area. The data shows that low elevations within the filled DEM maintain a high SPI value when compared to the unfilled DEM. The filled DEM also created a stream network similar to reality. The unfilled DEM demonstrated similar SPI results between all levels, indicating a well-connected karst system. In order to truly understand the mechanics of this system, a combination of these two DEMs is required.


Structure des rseaux karstiques: les contrles de la splogense pigne, 2011, Audra P. , Palmer A. N.

Cave development is related to the geomorphic evolution. Their morphology, preserved far longer than correlative surface features allows reconstructing the regional history of the surrounding landscape. Modeling shows that initial cave development occurs along the water table with loops in the phreatic zone along fractures. Consequently, cave profiles and levels reflect the local base level and its changes. Cave profile is controlled by timing, geological structure, and recharge. In first exposed rocks, juvenile pattern displays steep vadose passages. In perched aquifers, vadose erosion produces large passage along aquiclude. In dammed aquifers, the main drain is established at the water table when recharge is fairly regular. But when irregular recharge causes backflooding, looping profiles develop throughout the epiphreatic zone. Interconnected cave levels correspond to some of the largest cave systems in the world. The oldest abandoned highest levels have been dated beyond 3.5 Ma (Mammoth Cave). However, when base level rises, the deepest parts of the karst are flooded; the flow rises along phreatic lifts, and discharges at vauclusian springs. In the epiphreatic zone, floodwater produces looping tubes above the low-flow water table. In such a case of baselevel rise, per ascensum speleogenesis can produce higher-elevation passages that are younger than passages at lower elevations. base-level rises occur after tectonic subsidence, filling of valleys, or sea-level rise, as for instance around the Mediterranean in response to the Messinian Crisis. Deep-phreatic karst, if not hypogenic, can generally be attributed to flooding by a base-level rise. 


Using Geographic Information System to Identify Cave Levels and Discern the Speleogenesis of the Carter Caves Karst Area, Kentucky, 2011, Peterson E. , Dogwiler T. , Harlan L.

Cave level delineation often yields important insight into the speleogenetic history of a karst system. Various workers in the Mammoth Cave System (MCS) and in the caves of the Cumberland Plateau Karst (CPK) have linked cave level development in those karst systems with the Pleistocene evolution of the Ohio River. This research has shown that speleogenesis was closely related to the base level changes driven by changes in global climate. The Carter Caves Karst (CCK) in northeastern Kentucky has been poorly studied relative to the MCS to the west and the CPK karst to the east. Previously, no attempt had been made to delineate speleogenetic levels in the CCK and relate them to the evolution of the Ohio River. In an attempt to understand cave level development in CCK we compiled cave entrance elevations and locations. The CCK system is a fluviokarst typical of many karst systems formed in the Paleozoic carbonates of the temperate mid-continent of North America. The CCK discharges into Tygarts Creek, which ultimately flows north to join the Ohio River. The lithostratigraphic context of the karst is the Mississippian Age carbonates of the Slade Formation. Karst development is influenced by both bedding and structural controls. We hypothesize that cave level development is controlled by base level changes in the Ohio River, similar to the relationships documented in MCS and the karst of the Cumberland Plateau The location and elevation of cave entrances in the CCK was analyzed using a GIS and digital elevation models (DEMs). Our analysis segregated the cave entrances into four distinct elevation bands that we are interpreting as distinct cave levels. The four cave levels have mean elevations (relative to sea level) of 228 m (L1), 242 m (L2), 261 m (L3), and 276 m (L4). The highest level—L4—has an average elevation 72 m above the modern surface stream channel. The lowest level—L1—is an average of 24 m above the modern base level stream, Tygarts Creek. The simplest model for interpreting the cave levels is as a response to an incremental incision of the surface streams in the area and concomitant adjustment of the water table elevation. The number of levels we have identified in the CCK area is consistent with the number delineated in the MCS and CPK. We suggest that this points toward the climatically-driven evolution of the Ohio River drainage as controlling the speleogenesis of the CCK area 


Datierung fluviatiler Hhlensedimente mittels kosmogener Nuklide am Beispiel des Grazer Berglandes, 2011, Wagner, T.
The Central Styrian Karst north of Graz comprises a great number of caves of which many are of phreatic origin. Due to a clustering of caves at certain elevations above the current base level, the Mur River, these caves can be assigned to distinct levels. Caves cannot be older than the rock in which they formed, i.e. in the case of the region studied here not older than about 400 Ma (million years ago). Cave deposits on the other hand allow to infer a minimum age of cave formation, because they are deposited in the cave during or (mostly) after its development. Besides numerous autochthonous (i.e. in situ) sediments and speleothems, also a number of allochthonous (transported into the cave from the surface) sediments are encountered. Burial ages of several quartz-rich allochthonous cave sediments were determined using the radioactive cosmogenic nuclides 26Al and 10Be. The present article provides an insight into this rela tively new dating method (burial age dating) to constrain the age of cave deposits. The current state of knowledge about the timing of cave formation in the Grazer Bergland (Highland of Graz) will be discussed by summarizing the results of two recent papers (Wagner et al., 2010, 2011). Based on these results, conclusions are drawn about the age of the cave levels, relative incision rates of the River Mur and the landscape evolution of the eastern rim of the Alps in general. Sedimentation ages of 0 to about 5 Ma ago are in good agreement with increasingly higher cave levels above the present base level. This in turn reflects the stepwise relative incision of the River Mur. Based on the oldest samples, the onset of karstification and thus the exhumation of the Central Styrian Karst occurred at least 4-5 Ma ago. The oldest level, assigned to an age of at least 4 Ma, is situated some 500 m above the current valley bottom. Therefore, a relative incision rate of the River Mur in the order of only about 100 meters per million year (m/Myr) for the last 4-5 Ma is inferred. A more detailed examination of the levels reveals on average a decrease in the incision rate. Burial ages of ~2.5 Ma are determined only 100 m above the current base level. Moreover, the formation of planation surfaces and terraces in the Grazer Bergland is constrained by the correlation with cave levels and as such an important contribution to the understanding of landscape evolution of this region is made.

Geomorphological and sedimentological comparison of fluvial terraces and karst caves in Zhangjiajie, northwest Hunan, China: an archive of sandstone landform development, 2011, Yang Guifang, Zhang Xujiao, Tian Mingzhong, Ping Yamin, Chen Anze, Ge Zhiliang, Ni Zhiyun, Yang Zhen,

The Zhangjiajie Sandstone Peak Forest Geopark (Zhangjiajie World Geopark) of northwest Hunan, China hosts a well-preserved sequence of fluvial terraces and karst caves. In this contribution, a comparative study of fluvial terraces with karst caves along the middle-lower Suoxi River in Zhangjiajie World Geopark is presented to improve the understanding of the development of striking sandstone landscape in the upper Suoxi River. By integrating geomorphological, sedimentological, and geochronological techniques, the possible correlation between fluvial terraces and karst caves, as well as their climatic and tectonic implications is investigated. The available electron spin resonance and thermo-luminescence numerical ages coupled with morphostratigraphic analysis indicate that aggradation of fluvial terrace levels occurred at ca. 347 ± 34 ka (T4), 104.45 ± 8.88 to 117.62 ± 9.99 ka (T3), 60.95 ± 5.18 ka (T2), and Holocene (T1), followed by the stream incision. Fluvial terrace levels (T4 to T1) correlate morphologically with the karst cave levels (L1 to L4), yet the proposed chronology for the fluvial terrace levels is a bit later than the chronological data obtained from karst caves. In northwest Hunan, where a unique sandstone peak forest landscape was extensively developed, the fluvial terrace sequences as well as the cave systems are the important archives for studying the evolution of the sandstone landscape. The beginning of the sandstone landscape development must be earlier than the aggradation of the fluvial terrace T4, allowing this unique landscape to occur in the Middle Pleistocene.


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