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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 capillary conductivity is 1. the property of an unsaturated porous medium to transmit liquid [22]. 2. coefficient which expresses the extent to which an unsaturated permeable medium allows flow of water through its interstices, under a unit gradient of capillary potential [22].?

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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 dilution (Keyword) returned 44 results for the whole karstbase:
Showing 31 to 44 of 44
Inference of a karst conduit structure using quantitative tracer tests and geological observations, 2008, Perrin J. , Luetscher M.
Karst aquifers are known for being particularly heterogeneous with highly transmissive conduits embedded in low permeability volumes of rock matrix. Artificial tracer experiments have been carried out in a complex karst aquifer of the folded Jura Mountains in Switzerland with the aim of deciphering the conduit organisation. It is shown that tracer experiments with multiple injection points under different flow conditions can lead to useful information on the conduits? structure. This information has been combined with data from structural geology, spring hydrology, and speleological observations. A conceptual model of the conduit network shows that a detailed inference of the conduit organisation can be reached: geology controls conduit location and orientation; spring hydrology, including temporary springs, constrains conduit elevations and relative hydraulic heads in the aquifer subsystems; and tracer tests identify major flow paths and outlets of the system and dilution caused by nontraced tributaries, as well as the presence of secondary flow routes. This understanding of the Aubonne aquifer structure has important implications for the future management of the groundwater resource. Similar approaches coupling geological information, spring hydrology, and multi-tracer tests under various flow conditions may help to characterise the structure of the conduit network in karst aquifers.

Niche differentiation among sulfur-oxidizing bacterial populations in cave waters, 2008, Jennifer L Macalady, Sharmishtha Dattagupta, Irene Schaperdoth, Daniel S Jones, Greg K Druschel And Danielle Eastman
The sulfidic Frasassi cave system affords a unique opportunity to investigate niche relationships among sulfur-oxidizing bacteria, including epsilonproteobacterial clades with no cultivated representatives. Oxygen and sulfide concentrations in the cave waters range over more than two orders of magnitude as a result of seasonally and spatially variable dilution of the sulfidic groundwater. A full-cycle rRNA approach was used to quantify dominant populations in biofilms collected in both diluted and undiluted zones. Sulfide concentration profiles within biofilms were obtained in situ using microelectrode voltammetry. Populations in rock-attached streamers depended on the sulfide/oxygen supply ratio of bulk water (r¼0.97; Po0.0001). Filamentous epsilonproteobacteria dominated at high sulfide to oxygen ratios (4150), whereas Thiothrix dominated at low ratios (o75). In contrast, Beggiatoa was the dominant group in biofilms at the sediment?water interface regardless of sulfide and oxygen concentrations or supply ratio. Our results highlight the versatility and ecological success of Beggiatoa in diffusion-controlled niches, and demonstrate that high sulfide/oxygen ratios in turbulent water are important for the growth of filamentous epsilonproteobacteria.

Microscopic fungi isolated from the Domica Cave system (Slovak Karst National Park, Slovakia). A review, 2009, Novakova A.
A broad spectrum, total of 195 microfungal taxa, were isolated from various cave substrates (cave air, cave sediments, bat droppings and/or guano, earthworm casts, isopods and diplopods faeces, mammalian dung, cadavers, vermiculations, insect bodies, plant material, etc.) from the cave system of the Domica Cave (Slovak Karst National Park, Slovakia) using dilution, direct and gravity settling culture plate methods and several isolation media. Penicillium glandicola, Trichoderma polysporum, Oidiodendron cerealis, Mucor spp., Talaromyces flavus and species of the genus Doratomyces were isolated frequently during our study. Estimated microfungal species diversity was compared with literature records from the same substrates published in the past.

Microscopic fungi isolated from the Domica Cave system (Slovak Karst National Park, Slovakia). A review, 2009, Novkov, A.

A broad spectrum, total of 195 microfungal taxa, were isolated from various cave substrates (cave air, cave sediments, bat droppings and/or guano, earthworm casts, isopods and diplopods faeces, mammalian dung, cadavers, vermiculations, insect bodies, plant material, etc.) from the cave system of the Domica Cave (Slovak Karst National Park, Slovakia) using dilution, direct and gravity settling culture plate methods and several isolation media. Penicillium glandicola, Trichoderma polysporum, Oidiodendron cerealis, Mucor spp., Talaromyces flavus and species of the genus Doratomyces were isolated frequently during our study. Estimated microfungal species diversity was compared with literature records from the same substrates published in the past.

Automatic hydrochemical logging and in situ titration combined with laboratory analysis were used to understand the spatial and temporal hydrochemical variations of the spring-fed, travertine-depositing stream in celebrated Huanglong Ravine, Sichuan, SW China. This is essential for protection of the Huanglong World Natural Heritage travertine landscape. It was found that the deposition of travertine was due to very strong CO2 degassing from the water, leading to decrease in pCO2 and specific conductivity (SpC), and increase in pH and SIc downstream from the Spring. However, regular downstream hydrochemical evolution was interrupted by dilution with snowmelt water and by renewed CO2 from some downstream springs. The chemistry of Huanglong Spring itself was stable at a diurnal scale though it was altered by the great Wenchuan earthquake of May 12 2008. However, in spring-fed pools downstream, pCO2 and SpC were lower, and pH and SIc were higher in daytime than at night, which indicates that the deposition of travertine was faster during the daylight hours. This was due to the combined e?ects of higher water tempera-tures and higher aquatic algae photosynthesis. In addition, it was found that the phosphate concentration in the stream in-creased remarkably downstream in the tourist midseason, in-dicating water pollution by tourism activities. ?e increase of phosphate (an inhibitor of calcite precipitation) may be one of the reasons for the decrease in travertine deposition rates and accelerated propagation of discoloration by diatoms during the past decades, which needs to be given more comprehensive study and tackled in future for the protection of these world famous travertine deposits.Keywords: hydrochemical var

Catchment scale tracer testing from karstic features in a porous limestone, 2010, Maurice L. , Atkinson T. C. , Williams A. T. , Barker J. A. , Farrant A. R.

Tracer testing was undertaken from sinking streams feeding the Chalk, a porous limestone aquifer characterised by frequent small-scale surface karst features. The objective was to investigate the nature and extent of sub-surface karstic development in the aquifer. Previous tracer testing has demonstrated rapid flow combined with low attenuation of tracer. In this study, at two sites rapid groundwater flow was combined with very high attenuation and at two other sites no tracer was detected at springs within the likely catchment area of the stream sinks tested, suggesting that tracer was totally attenuated along the flowpath. It is proposed that the networks beneath stream sinks in the Chalk and other mildly karstic aquifers distribute recharge into multiple enlarged fractures that divide and become smaller at each division whereas the networks around springs have a predominantly tributary topology that concentrates flow into a few relatively large cavities, a morphology with similarities to that of the early stages of karstification. Tracer attenuation is controlled by the degree to which the two networks are directly connected. In the first state, there is no direct linkage and flow between the two networks is via primary fractures in which tracer attenuation is extreme. The second state is at a percolation threshold in which a single direct link joins the two networks. A very small proportion of tracer reaches the spring rapidly but overall attenuation is very high. In the third state, the recharge and discharge networks are integrated therefore a large fraction of tracer reaches the spring and peak concentrations are relatively high. Despite the large number of stream sinks that recharge the Chalk aquifer, these results suggest that sub-surface conduit development may not always be continuous, with flow down smaller fissures and fractures causing high attenuation of solutes and particulates providing a degree of protection to groundwater outlets that is not seen in more highly karstic aquifers. Bacteriophage tracers that can be detected at very large dilutions (1015) are recommended for investigating groundwater pathways where attenuation may be high.

The sulfidic thermal caves of Acquasanta Terme (central Italy), 2010, Galdenzi S. , Cocchioni F. , Filipponi G. , Morichetti L. , Scuri S. , Selvaggio R. , And Cocchioni M.

The caves of Acquasanta Terme (central Italy) open at the core of a wide anticline, in the valley of the Tronto River. Cave development is due to the rise of sulfidic thermal water flowing through a thick marine limestone sequence, overlain by thick, low- permeability formations. Some minor caves are developed in the terraced travertines deposited by the thermal water, but the major caves are developed in marine limestone in the small gorge of the Rio Garrafo stream, a tributary of the Tronto River. These caves have a rising pattern, due to the past flow of thermal water toward the surface. The deepening of the Tronto River Valley lowered the regional water table, perching the Rio Garrafo stream ,50 m above the thermal groundwater. At present, surface water sinks through the pre-existing karst passages to reach the thermal water flowing in the lower parts of the caves. Where these waters mix, rapid corrosion of the walls through sulfuric acid speleogenesis occurs. Annual temperature and chemistrymonitoring of the cave water showed that freshwater contributes up to 45% of the volume at the water table. Dilution events are associated with falling water temperature, which ranges between 44uC and 32uC. At the main spring, 2 km downstream, groundwater dilution was higher resulting in lower temperatures (32uC–21uC) and salinity. The periods of high freshwater dilution correspond with a lowering of pHin the phreatic water and with the release ofH2S and CO2 to the cave atmosphere. In the thermal zones, the concentration of H2S increased from 40 to over 240 ppm, while CO2 increased from 0.44% to 2.7%. These data evidence the influence of sinking surface water on the cave environment and speleogenesis.

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


This research is conducted in karst area, which is particularly enclosed by Bribin Underground River Catchment, Gunungkidul Regency. The objectives of this study are: (1) to understand spatial and temporal variation of flow characteristic as well as Diffuse Flow Proportion (PAD) of Bribin River; (2) to assess hydrogeochemistry and to recognize the relationship between hydrogeochemistry and flow characteristics of Bribin River, and (3) to define water agressivity of Bribin River with respect to carbonate mineral and to express the components of Karst Dynamic System (KDS) one-year behavior.
To define flow characteristic and PAD, three water level data loggers are installed within upper, lower and the leakage point along Bribin River continued by discharge measurement with the purpose of attaining stage-discharge rating curve. Afterwards, PAD is defined by conducting digital filtering baseflow separation approach after calculation of diffuse, fissure, and conduit recession constant. Next, to figure out hydrogeochemical condition, 120 sample of karst water are analyzed including rain, underground-river, and drip water. After that, scatter plots between hydrogeochemical parameters are conducted to achieve the correlation between PAD and hydrogeochemistry as well as to figure out hydrogeochemical processes to occur. Subsequently, Saturation Indices analysis with respect to calcite mineral and KDS components correlation is carried out to define karst water agressivity and its manners along flowpath of Bribin River.
The research’s result demonstrates that there is spatial and temporal differentiation of flow characteristics along Bribin River attributable to the comportment of karst aquifer toward discharging its diffuse, fissure, or conduit flow components, which consequence to the dissimilarity of PAD distribution along Bribin River. Accordingly, PAD characteristics result to dry season hydrogeochemical condition of Bribin River. However, wet season hydrogeochemical condition is more influenced by means of dilution by precipitation process within flood events, which exaggerates CO2 content of water. Generally, the upper-stream cave tend to more aggressive in dissolving limestone, contrast to down-steam cave that be inclined to precipitate carbonate mineral as a result of their differentiation of cavities configuration. In addition, down-stream cave is characterized by open system cavities, subsequent to the CO2 discharge to preserve dissolution process.

Hydrochemical variations of epikarst springs in vertical climate zones: a case study in Jinfo Mountain National Nature Reserve of China, 2011, Zhang Cheng, Yan Jun, Pei Jianguo, Jiang Yongjun

High temporal resolution (15 min) measurements of stage, pH, electric conductivity, temperature, and other hydrochemical parameters of groundwater at two sites in the Jinfo Mountain Nature Reserve of China were collected using automatic data loggers. Bitan Spring (BS 700 m a.s.l.) sits in subtropical climate zone, while Shuifang Spring (SS 2,060 m a.s.l.) is located in plateau temperate climate. The data show that hydrochemistry of epikarst springs at different altitudes is very sensitive to the changes of their physical environment, especially two factors: air temperature and soil CO2 concentration. Springs at lower altitude are associated with higher air temperature and soil CO2 concentration, thus more likely leading to more active karst processes than those at higher elevation. Water temperature and pH of BS showed a noticeable diurnal circle with high values in daytime and low values at night. The data also indicate that at least there are two effects that could impact the variations of groundwater hydrochemistry during flood pulse: dilution effect and CO2 effect.

The nature and distribution of flowing features in a weakly karstified porous limestone aquifer, 2012, Maurice L. D. , Atkinson T. C. , Barker J. A. , Williams A. T. , Gallagher A. J.

The nature and distribution of flowing features in boreholes in an area of approximately 400 km2 in a weakly karstic porous limestone aquifer (the Chalk) was investigated using single borehole dilution tests (SBDTs) and borehole imaging. One-hundred and twenty flowing features identified from SBDTs in 24 boreholes have densities which decrease from _0.3 m_1 near the water table to _0.07 m_1 at depths of more than 40 m below the water table; the average density is 0.20 m_1. There is some evidence of regional lithological control and borehole imaging of three boreholes indicated that most flowing features are associated with marls, hardgrounds and flints that may be developed at a more local scale. Borehole imaging also demonstrated that many flowing features are solutionally enlarged fractures, suggesting that even in carbonate aquifers where surface karst is developed on only a small scale, groundwater flow is still strongly influenced by dissolution. Fully connected solutional pathways can occur over 100s, sometimes 1000s of metres. However, conduits, tubules and fissures may not always be individually persistent along a flowpath, instead being connected together and also connected to unmodified fractures to create a relatively dense network of voids with variable apertures (<0.1 cm to >15 cm). Groundwater therefore moves along flowpaths made up of voids with varying shape and character. Local solutional development of fractures at significant depths below the surface suggests that mixing corrosion and in situ sources of acidity may contribute to solutional enhancement of fractures. The study demonstrates that single borehole dilution testing is a useful method of obtaining a large dataset of flowing features at catchment-regional scales. The Chalk is a carbonate aquifer with smallscale surface karst development and this study raises the question of whether other carbonate aquifers with small-scale surface karst have similar characteristics, and what hydrological role small-scale dissolutional features play in highly karstic aquifers.

Atmospheric Processes in Caves, 2013, James, J. M.

The cave atmosphere is placed in context as a geomorphic agent. The composition of cave air in well-ventilated caves isgoverned by exchange between surface and cave air. In poorly ventilated caves, its composition can be altered by dilution and production, and depletion of its components in the cave. Relative humidity is used to introduce water vapor as a critical component of cave air and its variations that result in evaporation of water and condensation of water vapor. The biogenicand inorganic reactions of oxygen and carbon dioxide control solution of limestone and precipitation of calcite. Condensation corrosion is a visual manifestation of atmospheric processes on bedrock and speleothems. Theories and experiment shave resulted in rates for condensation corrosion, which allow a preliminary assessment of its role as aspeleogenetic agent. The cave air carries particulates of both biogenic and inorganic origin; these can influence geomorphic processes in caves and provide significant paleoenvironmental information so as to past cave and surface events and climates. It is concluded that anthropogenic impacts can alter the atmospheric processes in caves.

Mycological study for a management plan of a neotropical show cave (Brazil)., 2013, Taylor E. L. S, Resendestoianoff M. A. A, Lopes Ferreira R.

Caves are stable environments with characteristics favoring the development of microorganisms. The allocthonous input of organic matter and microbes into the warm Neotropical caves may favor the development of filamentous fungi, including pathogenic species. Histoplasma capsulatum is a pathogenic species commonly found in caves and associated with bat and bird guano. Many Brazilian caves have been historically visited due to scenic and religious tourism. The objective of this study was to perform a microbiology study for a management plan of a show cave in Brazil, focusing on the presence and distribution of pathogenic and opportunistic fungi in the cave. Statistic analysis was used to verify the influence of touristic activity on airborne fungi spore load. Fungi were isolated from air and guano in Lapa Nova Cave. Samples were obtained through serial dilution, direct and settle plate techniques. For H. capsulatum, samples were incubated in specific media and conditions. Airborne fungal spore load was compared prior and during visitation and statistically analyzed. A total of 2,575 isolates from the genera Aspergillus, Calcarisporium, Chaetomium, Cladosporium, Curvularia, Emericella, Eurotium, Fusarium, Geotrichum, Gliocladium, Mucor, Purpureocillium, Paecilomyces, Penicillium, Rhizopus and Trichoderma were identified. Histoplasma capsulatum was not isolated from the cave. Eleven opportunistic species were identified. Significant (p<0.05) variations on fungal richness in the air occurred due to cave visitation. Areas of potential microbiologic risks were indicated and management actions suggested. The results suggest a diverse community inhabiting the cave. Possible opportunistic species should be monitored in show caves and microbiota should always be included in the elaboration of cave management plans. This is the first detailed microbiologic study for a management plan of a show cave in the country. It provides relevant information for future management plans.

Geochemistry and isotope geochemistry of the Monfalcone thermal waters (northern Italy): inference on the deep geothermal reservoir, 2013, Petrini R. , Italiano F. , Ponton M. , Slejko F. F. , Aviani U. , Zini L.

Geochemical investigations were carried out to define the origin of the low- to moderate-temperature thermal waters feeding the Monfalcone springs in northern Italy. Chemical data indicate that waters approach the composition of seawater. Mixing processes with cold low-salinity waters are highlighted. The δ18O and δD values are in the range −5.0 to −6.4 ‰, and −33 to −40 ‰, respectively, suggesting the dilution of the saline reservoir by karst-type freshwaters. A surplus of Ca2+ and Sr2+ ions with respect to a conservative mixing is ascribed to diagenetic reactions of the thermal waters with Cretaceous carbonates at depth. The measured Sr isotopic composition (87Sr/86Sr ratio) ranges between 0.70803 and 0.70814; after correction for the surplus Sr, a 87Sr/86Sr ratio indicating Miocene paleo-seawater is obtained. The dissolved gases indicate long-lasting gas–water interactions with a deep-originated gas phase of crustal origin, dominated by CO2 and marked by a water TDIC isotopic composition in the range −5.9 to−8.8 and helium signature with 0.08 < R/Ra < 0.27, which is a typical range for the crust. A possible scenario for the Monfalcone thermal reservoir consists of Miocene marine paleowaters which infiltrated through the karstic voids formed within the prevalently Cretaceous carbonates during the upper Eocene emersion of the platform, and which were entrapped by the progressive burial by terrigenous sediments.

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