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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 pillar is 1. remnant of bedrock joining the cave floor and ceiling. not to be confused with a column, which is a calcite deposit. pillars are common in phreatic caves, formed by complexly looping ground-water flow, but may also be left as small oxbow cores of vadose origin. a spectacular group of pillars occurs in the ill-named chamber of columns in the sof omar cave, ethiopia [9]. 2. a column of rock remaining after solution of the surrounding rock. 3. a stalactite-- stalagmite that reaches from roof to floor in a cave; more properly termed a column. 4. a tall thin stalagmite that does not reach the roof of a cave [10]. see column; rock pillar.?

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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 fluxes (Keyword) returned 56 results for the whole karstbase:
Showing 46 to 56 of 56
Annual and transient signatures of gas exchange and transport in the Castaar de Ibor cave (Spain)., 2009, Fernandezcortes A. , Sanchezmoral S. , Cuezva S. , Caaveras J. C. And Abella R.
The large microclimatic stability is a basic characteristic of the subterranean karst systems and causes a high sensitivity to changes in environmental conditions. High-accuracy monitoring of Castaar de Ibor cave (Spain) determined the temporal evolution of the aerodynamic processes and ventilation rate by tracking CO2 and 222Rn levels over a twelve-month period. This cave is characterized by a very stable microclimate, with high and relatively constant radon content (the mean value is 32200 Bq/m3, roughly, and the standard deviation is 7600 Bq/m3) and a moderate and quite stable CO2 concentration (the mean value is 3730 ppm and the standard deviation is 250 ppm). Beside the general patterns of cave microclimate throughout an annual cycle, some particular microclimatic processes are described with regard to the gas exchange between the cave and the outside atmosphere. There is a complex microclimatic functional relationship between the meteorological and cave microclimate conditions and the diffusion and flow of tracer gases from the fractures and the pore system of soil and host rock to cave atmosphere. Transient variations of tracer gas on cave air are controlled by natural barometric fluxes and anthropogenic forced ventilation due to uncontrolled opening of cave entrance. The short-term fluctuations of gas levels on cave air reveal distinct patterns during the exhalation process of theses gases from the net of fissures and pores to the cave atmosphere, depending on the isolation effect of soil and host rock.

Annual and transient signatures of gas exchange and transport in the Castaar de Ibor cave (Spain), 2009, Fernandezcortes A. , Sanchezmoral S. , Cuezva S. , Caaveras J. C. , Abella R.

The large microclimatic stability is a basic characteristic of the subterranean karst systems and causes a high sensitivity to changes in environmental conditions. High-accuracy monitoring of Castañar de Ibor cave (Spain) determined the temporal evolution of the aerodynamic processes and ventilation rate by tracking CO2 and 222Rn levels over a twelve-month period. This cave is characterized by a very stable microclimate, with high and relatively constant radon content (the mean value is 32200 Bq/m3, roughly, and the standard deviation is 7600 Bq/m3) and a moderate and quite stable CO2 concentration (the mean value is 3730 ppm and the standard deviation is 250 ppm). Beside the general patterns of cave microclimate throughout an annual cycle, some particular microclimatic processes are described with regard to the gas exchange between the cave and the outside atmosphere. There is a complex microclimatic functional relationship between the meteorological and cave microclimate conditions and the diffusion and flow of tracer gases from the fractures and the pore system of soil and host rock to cave atmosphere. Transient variations of tracer gas on cave air are controlled by natural barometric fluxes and anthropogenic forced ventilation due to uncontrolled opening of cave entrance. The short-term fluctuations of gas levels on cave air reveal distinct patterns during the exhalation process of theses gases from the net of fissures and pores to the cave atmosphere, depending on the isolation effect of soil and host rock.


Scale Analysis of the Significance of Dispersion in Mixing-Transport in Conduits, 2010, Li Guangquan, Shang Yulei, Gao Jun

Mixing-transport of solute entering at sinkholes or from within the limestone matrix in cavernous conduits is an important process for contaminant  migration in karst aquifers. This process may be described with a one-dimensional advection-dispersion equation incorporating the fluxes of solute and water across the conduit wall. For the dilution-dispersion equation, which does not include solute flux across the wall but has the flux of water through the wall, the sufficient and necessary condition for neglecting conduit dispersion is showed by scale analysis to be LP &a, where a is the conduit radius, and LP is the spatial scale of the solute plume. A straightforward necessary and practically, though not strictly, sufficient condition is a=WTB %1, where W is the mean velocity of conduit flow, and TB is the time scale of the breakthrough curve. For the releasing-dispersion equation, which includes the fluxes of water and solute across the wall, LP &a is still a sufficient condition, but no longer a necessary one. The inequality a%WTB is neither a necessary condition nor a sufficient condition.E18


Role of sediment in speleogenesis; sedimentation and paragenesis, 2011, Farrant Andrew R. , Smart Peter L.

Although the effects of sedimentation in caves have been recognised for many years, its role in speleogenesis is frequently overlooked. Influxes of sediment into a cave system fundamentally alter the way cave passages develop, either by alluviation in a vadose environment, forcing lateral corrosion and the development of notches, or by upwards dissolution in a phreatic environment through a process known as paragenesis. Sediment influxes affect the hydrological functioning of a karst aquifer by changing the way conduits behave and subsequently develop both in plan and long section.

Here we give an overview of the mechanisms of cave sedimentation and describe how the process of alluviation and paragenesis affect speleogenesis. A characteristic suite of meso- and micro-scale dissolutional features can be used to recognise paragenetic development, which is reviewed here. In a vadose environment these include alluvial notches, whilst in a phreatic environment, half tubes, anastomoses and pendants, bedrock fins and paragenetic dissolution ramps result. Using these to identify phases of sedimentation and paragenesis is crucial for reconstructing denudation chronologies from cave deposits. We suggest that sedimentation and paragenesis are most likely to occur in certain geomorphological situations, such as ice marginal and periglacial environments, beneath thick residual soils and where rivers can transport fluvial sediment into a cave, either via stream sinks or back-flooding.


Contaminant Transport in Two Central Missouri Karst Recharge Areas, 2011, Lerch, R. N.

Karst watersheds with significant losing streams represent a particularly
vulnerable setting for groundwater contamination because of the direct connection to surface water. Because of the existing agricultural land-use and future likelihood of urbanization, two losing-stream karst basins were chosen for intensive monitoring in Boone County, Missouri: Hunters Cave and Devils Icebox. Both caves were formed in Burlington Limestone and have similar recharge areas (33 to 34 km2) and land uses. Year-round monitoring was conducted from April 1999 through March 2002 to characterize the water quality of the main cave streams relative to herbicide, nutrient, and sediment contamination. Water sampling entailed grab samples at regular intervals and runoff-event samples collected using automated sampling equipment. Total nitrogen, phosphorus, and sediment concentrations and loads were consistently higher in the Devils Icebox stream compared to Hunters Cave. Median total N fluxes were 96 g km22 d21 at Devils Icebox and 30 g km22 d21 at Hunters Cave, while median total P fluxes were 8.5 g km22 d21 at Devils Icebox and 3.3 g km22 d21 at Hunters Cave. Herbicides or their metabolites were detected in more than 80% of the samples from both cave streams, and herbicide concentrations and areal loss rates were generally similar between the sites. Overall, the greater loads and mass flux of contaminants in the Devils Icebox recharge area compared to Hunters Cave was a result of both greater stream discharge and the occurrence of more cropped fields (94%) on claypan soils with high runoff potential. These claypan soils are known to be especially problematic with respect to surface transport of contaminants. Prevailing land use has significantly degraded the water quality in both recharge areas, but a watershed plan has been developed for the Bonne Femme watershed, which encompasses these two recharge areas. With the baseline data collected in this study, the impact of changing land uses and the implementation of management practices or new ordinances designed to improve water quality can be documented.


A Leaky-Conduit Model of Transient Flow in Karstic Aquifers, 2011, Loper David E. , Chicken Eric

Karst Flow Model (KFM) simulates transient flow in an unconfined karstic aquifer having a well-developed conduit system. KFM treats the springshed as a two-dimensional porous matrix containing a triangulated irregular network of leaky conduits. The number and location of conduits can be specified arbitrarily, perhaps using field information as a guide, or generated automatically. Conduit networks can be tree-like or braided. Rainwater that has infiltrated down from the surface leaks into the conduits from the adjacent porous matrix at a rate dictated by Darcy’s law, then flows turbulently to the spring via the conduits. KFM is calibrated using the known steady state; geometry and recharge determine the steady fluxes in the conduits, and the head distribution determines conduit gradients and sizes. Spring flow can vary with time due to spatially and temporally variable recharge and due to prescribed variations in the elevation of the spring. KFM is illustrated by four examples run on a test aquifer consisting of 27 nodes, 42 elements, and 26 conduits. Three examples (drought, uniform rainstorm, storm-water input to one element) are simulations, while the fourth uses data from a spring-basin flooding event. The qualitative fit between the predicted and observed spring discharge in the fourth example provides support of the hypothesis that the dynamic behavior of a karst conduit system is an emergent property of a self-organized system, largely independent of the locations and properties of individual conduits.


Mapping permeability over the surface of the Earth, 2011, Gleeson T. , Smith L. , Moosdorf N. , Hartmann J. , Durr H. H. , Manning A. H. , Van Beek L. P. H. , Jellinek A. M.

Permeability, the ease of fluid flow through porous rocks and soils, is a fundamental but often poorly quantified component in the analysis of regional-scale water fluxes. Permeability is difficult to quantify because it varies over more than 13 orders of magnitude and is heterogeneous and dependent on flow direction. Indeed, at the regional scale, maps of permeability only exist for soil to depths of 1–2 m. Here we use an extensive compilation of results from hydrogeologic models to show that regional-scale (>5 km) permeability of consolidated and unconsolidated geologic units below soil horizons (hydrolithologies) can be characterized in a statistically meaningful way. The representative permeabilities of these hydrolithologies are used to map the distribution of near-surface (on the order of 100 m depth) permeability globally and over North America. The distribution of each hydrolithology is generally scale independent. The near-surface mean permeability is of the order of 5 x 10-14 m2. The results provide the first global picture of near-surface permeability and will be of particular value for evaluating global water resources and modeling the influence of climate-surface-subsurface interactions on global climate change.

 

From soil to cave: Transport of trace metals by natural organic matter in karst dripwaters, 2012, Hartland A. , Fairchild I. J. , Lead J. R. , Borsato A. , Baker A. , Frisia S. , Baalousha M.

This paper aims to establish evidence for the widespread existence of metal binding and transport by natural organic matter (NOM) in karst dripwaters, the imprint of which in speleothems may have important climatic significance. We studied the concentration of trace metals and organic carbon (OC) in sequentially filtered dripwaters and soil leachates from three contrasting sites: Poole's Cavern (Derbyshire, UK), Lower Balls Green Mine (Gloucestershire, UK) and Grotta di Ernesto (Trentino, Italy). The size-distribution of metals in the three soils was highly similar, but distinct from that found in fractionated dripwaters: surface-reactive metals were concentrated in the coarse fraction (>100 nm) of soils, but in the fine colloidal (b100 nm) and nominally dissolved (b1 nm) fractions of dripwaters. The concentration of Cu, Ni and Co in dripwater samples across all sites were well correlated (R2=0.84 and 0.70, Cu vs. Ni, Cu vs. Co, respectively), indicating a common association. Furthermore, metal ratios (Cu:Ni, Cu:Co) were consistent with NICA-Donnan n1 humic binding affinity ratios for these metals, consistent with a competitive hierarchy of binding affinity (Cu>Ni>Co) for sites in colloidal or dissolved NOM. Large shifts in Cu:Ni in dripwaters coincided with high fluxes of particulate OC (following peak infiltration) and showed increased similarity to ratios in soils, diagnostic of qualitative changes in NOMsupply (i.e. fresh inputs of more aromatic/hydrophobic soil organic matter (SOM) with Cu outcompeting Ni for suitable binding sites). Results indicate that at high-flows (i.e. where fracture-fed flow dominates) particulates and colloids migrate at similar rates, whereas, in slow seepage-flow dripwaters, particulates (>1 μm) and small colloids (1–100 nm) decouple, resulting in two distinct modes of NOM–metal transport: high-flux and low-flux. At the hyperalkaline drip site PE1 (in Poole's Cavern), high-fluxes of metals (Cu, Ni, Zn, Ti, Mn, Fe) and particulate NOM occurred in rapid, short-lived pulses following peak infiltration events, whereas low-fluxes of metals (Co and V>Cu, Ni and Ti) and fluorescent NOM (b ca. 100 nm) were offset from infiltration events, probably because small organic colloids (1–100 nm) and solutes (b1 nm) were slower to migate through the porous matrix than particulates. These results demonstrate the widespread occurrence of both colloidal and particulate NOM–metal transport in cave dripwaters and the importance of karst hydrology in affecting the breakthrough times of different species. Constraints imposed by soil processes (colloid/particle release), direct contributions of metals and NOM from rainfall, and flow-routing (colloid/particle migration) are expected to determine the strength of correlations between NOM-transported metals in speleothems and climatic signals. Changes in trace metal ratios (e.g. Cu:Ni) in speleothems may encode information on NOMcomposition, potentially aiding in targeting of compound-specific investigations and for the assessment of changes in the quality of soil organic matter.


Carbon cycle in the epikarst systems and its ecological effects in South China, 2012, Jiang Z. , Lian Y. , Qin X.

The carbon cycle in a global sense is the biogeochemical process by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the earth. For epikarst systems, it is the exchange of carbon among the atmosphere, water, and carbonate rocks. Southern China is located in the subtropical zone; its warm and humid weather creates favorable conditions for the dynamic physical, chemical, and ecological processes of the carbon cycle. This paper presents the mechanisms and characteristics of the carbon cycle in the epikarst systems in south China. The CO2 concentration in soils has clear seasonal variations, and its peak correlates well with the warm and rainy months. Stable carbon isotope analysis shows that a majority of the carbon in this cycle is from soils. The flow rate and flow velocity in an epikarst system and the composition of carbonate rocks control the carbon fluxes. It was estimated that the karst areas in south China contribute to about half of the total carbon sink by the carbonate system in China. By enhancing the movement of elements and dissolution of more chemical components, the active carbon cycle in the epikarst system helps to expand plant species. It also creates favorable environments for the calciphilic plants and biomass accumulation in the region. The findings from this study should help in better understanding of the carbon cycle in karst systems in south China, an essential component for the best management practices in combating rock desertification and in the ongoing study of the total carbon sink by the karst flow systems in China


The new global lithological map database GLiM: A representation of rock properties at the Earth surface, 2012, Hartmann Jens, Moosdorf Nils

Lithology describes the geochemical, mineralogical, and physical properties of rocks. It plays a key role in many processes at the Earth surface, especially the fluxes of matter to soils, ecosystems, rivers, and oceans. Understanding these processes at the global scale requires a high resolution description of lithology. A new high resolution global lithological map (GLiM) was assembled from existing regional geological maps translated into lithological information with the help of regional literature. The GLiM represents the rock types of the Earth surface with 1,235,400 polygons. The lithological classification consists of three levels. The first level contains 16 lithological classes comparable to previously applied definitions in global lithological maps. The additional two levels contain 12 and 14 subclasses, respectively, which describe more specific rock attributes. According to the GLiM, the Earth is covered by 64% sediments (a third of which are carbonates), 13% metamorphics, 7% plutonics, and 6% volcanics, and 10% are covered by water or ice. The high resolution of the GLiM allows observation of regional lithological distributions which often vary from the global average. The GLiM enables regional analysis of Earth surface processes at global scales. A gridded version of the GLiM is available at the PANGEA Database (http://dx.doi.org/10.1594/PANGAEA.788537).


Carbon fluxes in Karst aquifers: Sources, sinks, and the effect of storm flow, 2013, White William B.

An effective carbon loading can be calculated from measured alkalinity and pH of karst waters. The carbon loading is independent of the degree of saturation of the water and does not depend on the water being in equilibrium with the carbonate wall rock. A substantial data base of spring water analyses accumulated by students over the past 40 years has been used to probe the CO2 generation, transport, and storage in a variety of drainage basins that feed karst springs. Carbon loading in the water exiting karst drainage basins depends on the rate of CO2 generation in the soils of the catchment areas and on the partitioning between CO2 dissolved in infiltration water and CO2 lost by diffusion upward to the atmosphere. For any given drainage basin there are also influences due to vegetative cover, soil type, and the fraction of the water provided by sinking stream recharge. Losses of CO2 back to the atmosphere occur by speleothem deposition in air-filled caves, by degassing of CO2 in spring runs, and by tufa deposition in spring runs. There are seasonal cycles of CO2 generation that relate growing season and contrasts in winter/summer rates of CO2 generation. Overall, it appears that karst aquifers are a net, but leaky, sink for atmospheric CO2


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