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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 karst bridge is a natural bridge or arch in limestone [10].?

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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 snow (Keyword) returned 57 results for the whole karstbase:
Showing 46 to 57 of 57
Geomorphological Characteristics of the Italian Side of Canin Massif (Julian Alps) using Digital Terrain Analysis and Field Observations , 2011, Telbisz Tams, Mari Lszl, Szab Lnrd

In this paper, by the example of Canin Massif, it is demon­strated, how GIS-techniques can be used for the study of high mountain karst terrains. In case of Canin, elevation and slope histograms show characteristic differences in plateau levels and landforming processes between the northern, western and southern sectors of the mountains. Ridge and valley map (de­rived from the digital elevation model) and thalweg analysis are used to recognize drainage reorganizations north of the Italian Canin plateau. Potential snow accumulation locations and nu­nataks are determined based mainly on the slope map. Geo­morphological sketch maps and statistical analysis of closed depressions are also carried out in this study supporting the relatively young age of superficial karstification and the strong structural impact. Finally, it is concluded, that quantitative and visual capabilities of GIS are useful in discriminating the effects of glacial, fluvial, structural and karst processes.


Mechanisms of heat exchange between water and rock in karst conduits, 2011, Covington M. D. , Luhmann A. J. , Gabrovsek F. , Saar M. O. , Wicks C. M.

Previous studies, motivated by understanding water quality, have explored the mechanisms for heat transport and heat exchange in surface streams. In karst aquifers, temperature signals play an additional important role since they carry information about internal aquifer structures. Models for heat transport in karst conduits have previously been developed; however, these models make different, sometimes contradictory, assumptions. Additionally, previous models of heat transport in karst conduits have not been validated using field data from conduits with known geometries. Here we use analytical solutions of heat transfer to examine the relative importance of heat exchange mechanisms and the validity of the assumptions made by previous models. The relative importance of convection, conduction, and radiation is a function of time. Using a characteristic timescale, we show that models neglecting rock conduction produce spurious results in realistic cases. In contrast to the behavior of surface streams, where conduction is often negligible, conduction through the rock surrounding a conduit determines heat flux at timescales of weeks and longer. In open channel conduits, radiative heat flux can be significant. In contrast, convective heat exchange through the conduit air is often negligible. Using the rules derived from our analytical analysis, we develop a numerical model for heat transport in a karst conduit. Our model compares favorably to thermal responses observed in two different karst settings: a cave stream fed via autogenic recharge during a snowmelt event, and an allogenically recharged cave stream that experiences continuous temperature fluctuations on many timescales.


Influence of Karst Landscape on Planetary Boundary Layer Atmosphere: A Weather Research and Forecasting (WRF) ModelBased Investigation, 2011, Leeper R. Mahmood R, Quintanar A. I.

Karst hydrology provides a unique set of surface and subsurface hydrological components that affect soilmoisture variability. Over karst topography, surface moisture moves rapidly below ground via sink holes,vertical shafts, and sinking streams, reducing surface runoff and moisture infiltration into the soil. In addition,subsurface cave blockage or rapid snowmelt over karst can lead to surface flooding. Moreover, regionsdominated by karst may exhibit either drier or wetter soils when compared to nonkarst landscape. However,because of the lack of both observational soil moisture datasets to initialize simulations and regional landsurface models (LSMs) that include explicit karst hydrological processes, the impact of karst on atmosphericprocesses is not fully understood. Therefore, the purpose of this study was to investigate the importance ofkarst hydrology on planetary boundary layer (PBL) atmosphere using the Weather Research and ForecastingModel (WRF). This research is a first attempt to identify the impacts of karst on PBL. To model the influenceof karst hydrology on atmospheric processes, soil moisture was modified systematically over the WesternKentucky Pennyroyal Karst (WKYPK) region to produce an ensemble of dry and wet anomaly experiments.Simulations were conducted for both frontal- and nonfrontal-based convection. For the dry ensemble, cloudcover was both diminished downwind of karst because of reduced atmospheric moisture and enhanced slightlyupwind as moist air moved into a region of increased convection compared to control simulations (CTRL).Moreover, sensible (latent) heat flux and PBL heights were increased (decreased) compared to CTRL. Inaddition, the wet ensemble experiments reduced PBL heights and sensible heat flux and increased cloud coverover karst compared to CTRL. Other changes were noted in equivalent potential temperature (ue) andvertical motions and development of new mesoscale circulation cells with alterations in soil moisture overWKYPK. Finally, the location of simulated rainfall patterns were altered by both dry and wet ensembles withthe greatest sensitivity to simulated rainfall occurring during weakly forced or nonfrontal cases. Simulatedrainfall for the dry ensemble was more similar to the North American Regional Reanalysis (NARR) thanCTRL for the nonfrontal case. Furthermore, the initial state of the atmosphere and convective triggers werefound to either enhance or diminish simulated atmospheric responses


Eisdatierung und Eisvernderungen im Kraterschacht (1651/24, Sengsengebirge, Obersterreich) zwischen 1992 und 2009 , 2011, Weimair, R.
The Kraterschacht (1651/24) in the Sengsengebirge (Upper Austria) opens at an altitude of 1500 m at the southern flank of this high alpine mountain range. Discovered in 1990, the shaft leads to a depth of 250 m through two main chambers, the entrance shaft reaching 90 m and finally a huge chamber of some 150.000 m. This fault-oriented passage is largely filled with cave-ice that formed due to the compression of snow that easily entered through the entrance shaft with its cross sectional area of 700 m. From 1992 to 2009 the cave-ice body with an ice-density up to 880 kg/m lost 6000 m (6%) of its volume. This is only three times more than the annual fluctuation of ice volume. The 14C-age of a small twig from near the ice-base (1030 to 1225 AD) points towards a most likely high-medieval age of the cave-ice.

Verbindung des Unfallschachts mit der Dachstein-Mammuthhle (1547/9) , 2011, Behm, M.
On 21st of August, 2010, the connection between the Unfallschacht (1547/240) and the Dachstein-Mammuthhle (DMH, 1547/9) was found in 180 m depth of the Unfallschacht. This pit was explored in October 2009 when the discovery of a human corpse at the bottom of the 54 m deep entrance pit stopped further investigation of the cave. The body belonged to a snowboarder who was missing since February 2009. The Unfallschacht is located at an elevation of 1750 m and leads into a large canyon which can be descended down to the Riesenkluft of DMH. The upper parts of Riesenkluft have been explored since 2008 which included technical climbing of several high walls in an active canyon system. After 200 m vertical ele - vation had been surmounted, the horizontal base of a strongly ventilated and active canyon was reached. The stream is fed from a sump and eventually just above this sump the connection was made. Strong venti - lation in the upper part of the Unfallschacht indicates continuation of the canyon towards the south and the possible existence of higher entrances. The current length of the DMH is 66,532 m, and its difference in elevation is 1207 m.

Microbiological Activities in Moonmilk Monitored Using Isothermal Microcalorimetry (Cave of Vers Chez Le Brandt, Neuchatel, Switzerland), 2012, Braissant O. , Binderschedler S. , Daniels A. U. , Verrecchia E. P. , Cailleau G.

 

Studies of the influence of microbial communities on calcium carbonate deposits mostly rely on classical or molecular microbiology, isotopic analyses, and microscopy. Using these techniques, it is difficult to infer microbial activities in such deposits. In this context, we used isothermal microcalorimetry, a sensitive and nondestructive tool, to measure microbial activities associated with moonmilk ex-situ. Upon the addition of diluted LB medium and other carbon sources to fresh moonmilk samples, we estimated the number of colony forming units per gram of moonmilk to be 4.8 3 105 6 0.2 3 105. This number was close to the classical plate counts, but one cannot assume that all active cells producing metabolic heat were culturable. Using a similar approach, we estimated the overall growth rate and generation time of the microbial community associated with the moonmilk upon addition of various carbon sources. The range of apparent growth rates of the chemoheterotrophic microbial community observed was between 0.025 and 0.067 h21 and generation times were between 10 and 27 hours. The highest growth rates were observed for citrate and diluted LB medium, while the highest carbon-source consumption rates were observed for low molecular weight organic acids (oxalate and acetate) and glycerol. Considering the rapid degradation of organic acids, glucose, and other carbon sources observed in the moonmilk, it is obvious that upon addition of nutrients during snow melting or rainfall these communities can have high overall activities comparable to those observed in some soils. Such communities can influence the physico-chemical conditions and participate directly or indirectly to the formation of moonmilk.


Origin of the limestone pedestals at Norber Brow, North Yorkshire, UK: a re-assessment and discussion, 2012, Wilson Peter, Lord Tom C. , Vincent Peter. J.

Contrasting rates of limestone dissolution to account for the development of limestone pedestals beneath erratic boulders at Norber, North Yorkshire, have been proposed. Most of these estimates were made prior to reliable dates being available for erratic emplacement and prior to detailed knowledge of the pattern of regional 'post-glacial' climate change. The erratics were deposited c. 18 ka BP, and for a substantial part of the ensuing c. 4 ka a climate of Arctic severity prevailed until the abrupt warming at 14.7 ka BP, marking the onset of the Lateglacial Interstadial. We propose that nivation (snow-related) processes operated for much of that time, and again during the Younger Dryas Stadial (12.9 - 11.7 ka BP), and made a contribution to the lowering of the limestone surface by both mechanical and chemical action. Similar processes are likely to have operated for short periods on several occasions during the Holocene when, according to proxy records, climate deteriorated. We question previous views that dissolution occurred in an entirely temperate sub-regolith environment and/or was achieved solely by rainfall.


Quantifying Concentrated and Diffuse Recharge in Two Marble Karst Aquifers: Big Spring and Tufa Spring, Sequoia and Kings Canyon National Parks, California, USA, 2012, Tobin B. , Schwartz B. ,

To improve water management in mountain systems, it is essential that we understand how water moves through them. Researchers have documented the importance of porous-media aquifers in mountain river systems, but no previous research has explicitly included mountain karst as part of conceptual models. To do so, we used discharge and geochemical parameters measured along upstreamto- downstream transects under high- and low-flow conditions in 2010 to assess storage characteristics and geochemical properties of two mountain marble-karst systems, the Big Spring and Tufa Spring systems in Sequoia and Kings Canyon National Parks, California. During both high- and low-flow conditions, we quantified the relative contributions of concentrated and diffuse recharge in both karst systems, and we used a simple linear mixing model to calculate specific conductance in unsampled diffuse sources that ranged from 34 mS cm21 to 257 mS cm21. Data show that the Big Spring system has a much higher seasonal storage capacity than the Tufa Spring system, and that diffuse sources dominate discharge and geochemistry under baseflow conditions in both aquifer systems. Baseflow in Big Spring was 0.114 m3 s21 and in Tufa Spring it was 0.022 m3 s21. Snowmelt-derived allogenic recharge dominates both systems during high discharge periods, measured at Big Spring as 0.182 m3 s21 and Tufa Spring as 0.220 m3 s21. A conceptual model is proposed that explicitly includes the effects of karst aquifers on mountain hydrology when karst is present in the basin.


LAG AND TRANSFER TIME INFERRED FROM MELTING CYCLES RECORD IN THE COULOMP KARST SPRING (ALPES DE HAUTE-PROVENCE, FRANCE), 2013, Audra Philippe, Nobecourt Jeanclaude

 

A 11-days long period of snowmelt cycles was selected from the discharge and temperature data collected at Coulomp spring (Alpes de Haute-Provence, France), which is the largest of French Southern Alps with a discharge of 1 m3/s. Its catchment is 30–50 km2-large and mainly composed of marly limestones and poorly permeable covers, responsible of a combined diffuse and concentrated recharge. From Q data we extracted snowmelt discharge (Snowmelt Q = oscillating part of the discharge) and Basal Q. The contribution of Snowmelt Q is 30–50 % of Q. Amplitude of spring temperature (Tspring) is about 2 °C due to alternation of cold snowmelt water with low residence time and “warm” phreatic water with longer residence time. The lag between the peak of air temperature (Tair) corresponding to the maximum of snow melting and the peaks of Q, corresponding to the transfer time between surface and spring, is less than 10 h. This 10 h transfer time combines about 7 h of vertical transfer through the vadose zone and 3 h of horizontal transfer through the drain.


KARST DEVELOPMENT IN THE GLACIATED AND PERMAFROSTREGIONS OF THE NORTHWEST TERRITORIES, CANADA, 2013, Ford Derek

 

The Northwest Territories of Canada are ~1.2 million km2 in area and appear to contain a greater extent and diversity of karst landforms than has been described in any other region of the Arctic or sub-Arctic. The Mackenzie River drains most of the area. West of the River, the Mackenzie Mountains contain spectacular highland karsts such as Nahanni (Lat. 62° N) and Canol Road (Lat. 65° N) that the author has described at previous International Speleological Congresses. This paper summarizes samples of the mountain and lowland karst between Lats. 64–67° N that are located east of the River. The Franklin Mountains there are east-facing cuestas created by over-thrusting from the west. Maximum elevations are ~1,000 m a.s.l., diminishing eastwards where the cuestas are replaced by undeformed plateaus of dolomite at 300–400 m asl that overlook Great Bear Lake. In contrast to the Mackenzie Mountains (which are generally higher) all of this terrain was covered repeatedly by Laurentide Continental glacier ice flowing from the east and southeast. The thickness of the last ice sheet was >1,200 m. It receded c.10,000 years ago. Today permafrost is mapped as “widespread but discontinuous” below 350 m a.s.l. throughout the region, and “continuous” above that elevation. The vegetation is mixed taiga and wetlands at lower elevations, becoming tundra higher up. Access is via Norman Wells (population 1,200), a river port at 65° 37’N, 126° 48’W, 67 m a.s.l.: its mean annual temperature is -6.4 °C (January mean -20 °C, July +14 °C) and average precipitation is ~330 mm.y-1, 40 % falling as snow. In the eastern extremities a glacial spillway divides the largest dolomite plateau into “Mahony Dome” and “Tunago Dome”. The former (~800 km2) has a central alvar draining peripherally into lakes with overflow sinkholes, turloughs, dessicated turloughs, and stream sinks, all developed post-glacially in regular karst hydrologic sequences. Tunago Dome is similar in extent but was reduced to scablands by a sub-glacial mega-flood from the Great Bear basin; it is a mixture of remnant mesas with epikarst, and wetlands with turloughs in flood scours. Both domes are largely holokarstic, draining chiefly to springs at 160–180 m a.s.l. in the spillway. The eastern limit of overthrusting is marked by narrow ridges created by late-glacial hydration of anhydrite at shallow depth in interbedded dolostones and sulphate rocks. Individual ridges are up to 60 km long, 500–1,000 m wide, 50–250 m in height. They impound Lac Belot (300 km2), Tunago Lake (120 km2) and many lesser lakes, all of which are drained underground through them. In the main overthrust structures, the Norman Range (Franklin Mountains) is oriented parallel with the direction of Laurentide ice flow. It displays strongly scoured morphology with elongate sinkholes on its carbonate benches. In contrast, the Bear Rock Range is oriented across the ice flow, has multiple cuestas, is deeply furrowed and holokarstic but preserves pinnacle karst on higher ground due to karst-induced polar thermal (frozen-down) conditions at the glacier base there.


Karstification as a Predisposing Factor of Seismically Triggered Landslides: Case Study from the Crimean Mountains (Ukraine): Introduction to the Problem, 2013, Hradeck J. , Pnek T. , ilhn K. , Smolkov V.

Deep-seated gravitational deformations are significant denudational agents of rock slopes at the margins of karstified plateaus of the Crimean Mountains (CM). The CM evolved during Mesozoic–Cenozoic times as a response to the deformation between the Black Sea domain and East-European platform. The southwestern part of the area is characterized by steep, up to 1000-m-high coastal escarpments consisting of Late Jurassic limestones overlying tuff layers and weak Late Triassic flysch with sporadic small intrusions of Middle Jurassic diorites, gabbros and granites. Steep rock slopes contrast with elevated, highly karstified plateaus situated approximately 500–1300 m a.s.l. The aim of this article is to show long-term evolution of a giant rock slope failure close to the Black Sea coast in the southwestern tip of the CM near Foros Town. The failure evolved in highly anisotropic limestones overlying plastic flysch layers where the main head scarp follows a strike-slip fault. The Foros slope failure is an excellent demonstration of the significance of a preparatory stage in the evolution of large deep-seated slope deformations. Inherited and undisturbed horizontal slickensides on the sub-vertical, inactive fault surface serve as good evidence of significant extensional movement of the surface blocks away from the main headscarp. The studied deformation shows that in a relatively small area tensional (cutting) surfaces can be formed by a great variety of rock discontinuities such as the strike-slip fault, joints and steeply inclined bedding planes. The presence of well-developed, nowadays weathered, speleothems furthermore points to significant karstification that provided additional widening of spaces within rock mass. Gravitational movement destroyed and unroofed several cave systems originally presented at the former edge of a karst plateau. Our findings reveal that large rock slope failures can be added to the factors contributing to the evolution of unroofed caves. Although triggering factors of the activation of individual parts of slope deformations can be determined only hypothetically, lessons learned from widespread landslide activity during and after the 1927 Yalta earthquake and rainfall-driven landslides in the vicinity of Feodosia Town make us consider both seismic loading of slopes and high pore-pressures during heavy winter rainfalls or rapid spring snowmelt to be significant factors. Beside seismic activity, intensive Late Holocene slope processes can be attributed to intensive human activity.

 


The hydrogeology of high-mountain carbonate areas: an example of some Alpine systems in southern Piedmont (Italy), 2015,

The hydrogeological characteristics of some springs supplied by high-mountain carbonate rock aquifers, located in the south of Piedmont, in Italy, are presented in this work. The aquifers have different geological-structural conditions, including both deep and superficial karstification. Their catchment areas are located in a typical Alpine context at a high altitude of about 2000 m. These aquifers are ideal representations of the different hydrogeological situations that can be encountered in the high-altitude carbonate aquifers of the Mediterranean basin. It is first shown how the high-altitude zones present typical situations, in particular related to the climate, which control the infiltration processes to a great extent. Snowfall accumulates on the ground from November to April, often reaching remarkable thicknesses. The snow usually begins to melt in spring and continues to feed the aquifer for several months. This type of recharge is characterized by continuous daily variations caused by the typical thermal excursions. The hourly values are somewhat modest, but snowmelt lasts for a long time, beginning in the lower sectors and ending, after various months, in the higher areas. Abundant rainfall also occurs in the same period, and this contributes further to the aquifer supply. In the summer period, there is very little rainfall, but frequent storms. In autumn, abundant rainfall occurs and there are there fore short but relevant recharge events. It has been shown how the trend of the yearly flow of the high mountain springs is influenced to a great extent by the snowmelt processes and autumn rainfall. It has also been shown, by means of the annual hydrographs of the flow and the electric conductivity of the spring water, how the different examined aquifers are characterized by very different measured value trends, according to the characteristics of the aquifer.

 


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