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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 subcutaneous zone is synonym for epikarst zone. see epikarstic zone.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for age (Keyword) returned 2952 results for the whole karstbase:
Showing 1 to 15 of 2952
Conduit enlargement in an eogenetic karst aquifer, , Moore Paul J. , Martin Jonathan B. , Screaton Elizabeth J. , Neuhoff Philip S.

Most concepts of conduit development have focused on telogenetic karst aquifers, where low matrix permeability focuses flow and dissolution along joints, fractures, and bedding planes. However, conduits also exist in eogenetic karst aquifers, despite high matrix permeability which accounts for a significant component of flow. This study investigates dissolution within a 6-km long conduit system in the eogenetic Upper Floridan aquifer of north-central Florida that begins with a continuous source of allogenic recharge at the Santa Fe River Sink and discharges from a first-magnitude spring at the Santa Fe River Rise. Three sources of water to the conduit include the allogenic recharge, diffuse recharge through epikarst, and mineralized water upwelling from depth. Results of sampling and inverse modeling using PHREEQC suggest that dissolution within the conduit is episodic, occurring only during 30% of 16 sampling times between March 2003 and April 2007. During low flow conditions, carbonate saturated water flows from the matrix to the conduit, restricting contact between undersaturated allogenic water with the conduit wall. When gradients reverse during high flow conditions, undersaturated allogenic recharge enters the matrix. During these limited periods, estimates of dissolution within the conduit suggest wall retreat averages about 4 × 10−6 m/day, in agreement with upper estimates of maximum wall retreat for telogenetic karst. Because dissolution is episodic, time-averaged dissolution rates in the sink-rise system results in a wall retreat rate of about 7 × 10−7 m/day, which is at the lower end of wall retreat for telogenetic karst. Because of the high permeability matrix, conduits in eogenetic karst thus enlarge not just at the walls of fractures or pre-existing conduits such as those in telogenetic karst, but also may produce a friable halo surrounding the conduits that may be removed by additional mechanical processes. These observations stress the importance of matrix permeability in eogenetic karst and suggest new concepts may be necessary to describe how conduits develop within these porous rocks.


Paleoclimate and location of the border between Mediterranean climate region and the Saharo-Arabian Desert as revealed by speleothems from the northern Negev Desert, Israel, , Vaks A. , Barmatthews M. , Ayalon A. , Matthews A. , Frumkin A. , Dayan U. , Halicz L. , Mogilabin A. , Schilman B. ,
Speleothem bearing karstic caves of the northern Negev Desert, southern Israel, provides an ideal site for reconstructing the paleoclimate and paleo-location of the border between Mediterranean climate region and the Saharo-Arabian Desert. Major periods of speleothem deposition (representing humid periods) were determined by high resolution 230Th-U dating and corresponding studies of stable isotope composition were used to identify the source of rainfall during humid periods and the vegetation type. Major humid intervals occurred during glacials at 190-150[no-break space]ka, 76-25[no-break space]ka, 23-13[no-break space]ka and interglacials at 200-190[no-break space]ka, 137-123[no-break space]ka and 84-77[no-break space]ka. The dominant rainfall source was the Eastern Mediterranean Sea, with a possible small contribution from southern tropical sources during the interglacial periods. When the interglacial interval rainfall was of Eastern Mediterranean origin, the minimum annual rainfall was ~ 300-350[no-break space]mm; approximately twice than of the present-day. Lower minimum amounts of precipitation could have occurred during glacial periods, due to the cooler temperatures and reduced evaporation. Although during most of the humid periods the vegetation remained steppe with mixed C3 C4 vegetation, Mediterranean C3 type steppe-forest vegetation invaded southward for short periods, and the climate in the northern Negev became closer to Mediterranean type than at present. The climate was similar to present, or even more arid, during intervals when speleothem deposition did not occur: 150-144[no-break space]ka, 141-140[no-break space]ka, 117-96[no-break space]ka, 92-85[no-break space]ka, 25-23[no-break space]ka, and 13[no-break space]ka-present-day.Precipitation increase occurred in the northern Negev during the interglacial monsoonal intensity maxima at 198[no-break space]ka, 127[no-break space]ka, 83[no-break space]ka and glacial monsoonal maxima at 176[no-break space]ka, 151[no-break space]ka, 61[no-break space]ka and 33[no-break space]ka. However, during interglacial monsoonal maxima at 105[no-break space]ka and 11[no-break space]ka, the northern Negev was arid whereas during glacial monsoonal minima it was usually humid. This implies that there is not always synchroneity between monsoonal activity and humidity in the region.Oxygen isotopic values of the northern Negev speleothems are systematically lower than contemporaneous speleothems of central and northern Israel. This part is attributed to the increased rainout of the heavy isotopes by Rayleigh fractionation processes, possibly due to the farther distance from the Mediterranean coast

Origin of the sedimentary deposits of the Naracoorte Caves, South Australia, , Forbes Ms, Bestland Ea,
The origin of the sediments located in the Naracoorte Caves (South Australia) was investigated via the analysis of strontium isotope ratios (87Sr/86Sr), elemental geochemistry, and mineralogy. Sedimentary deposits located in Robertson, Wet, Blanche and several other chambers in Victoria Cave are all variable mixes of fine sand and coarse silts, which display similar and consistent strontium isotope ratios (0.717-0.725). This suggests that over the 400[no-break space]ka time frame that these deposits span there has been minimal variation in the source of the clastic sediments. Increased strontium concentrations for these cave sediments correspond with increasing silt content, yet there is no correlation between 87Sr/86Sr ratios and silt content. This implies that the silt-sized component of the sediments is the main contributor of strontium to the cave sediments. Comparisons of 87Sr/86Sr with regional surficial deposits show a significant correlation between the cave sediments (avg: 0.7228; n = 27), the fine silt lunettes of the Bool Lagoon area (avg: 0.7224; n = 4), the sandy A horizons of the Coonawarra Red Brown Earths (RBEs; avg: 0.726; n = 5), and Holocene age podsolic sand deposits (0.723). These data suggest that there has been substantial flux from this group of deposits to the caves, as would be expected considering prevailing winds. This relationship is further supported by a strong correlation between many trace elements, including Ti, Zr, Ce, and Y; however, variations in clay mineralogy suggest that the fine silt-dominated lunettes and Padthaway RBEs were not significant contributors to the cave deposits. Hence, the detritus entering the caves was more than likely from areas proximal to the cave entrance and was dominated by medium grain-sized materials. Major regional deposits, including the coarser-grained, calcite-rich Bridgewater Formation sands, basalts from the lower SE, Padthaway Horst granites, Gambier limestone, and metamorphics from the Adelaide geosyncline show minimal correlation in 87Sr/86Sr ratios, elemental geochemistry, and mineralogy with the cave sediments, and are discounted as significant sources. In comparison, 87Sr/86Sr ratios for the Coorong silty sands (0.717-0.724), Lower Murray sands (0.727-0.730), and the medium size silt component of the Murray-Darling River system (0.71-0.72), compare favourably with the cave sediments. This relationship is further supported by similarities in elemental chemistry and mineralogy. Thus, much of the strontium-rich silt that is now located in the Naracoorte Cave sediments likely originated from the Murray-Darling basin. Over time, this material has been transported to the SE of South Australia, where it mixed with the medium sand component of the regressive dune ridge sequence, locally derived organic matter, limestone fragments, and fossil material to produce the unique deposits that we see evident in many of the chambers of the Naracoorte Cave system today

Significance and origin of very large regulating power of some karst aquifers in the Middle East. Implication on karst aquifer classification, , Elhakim M, Bakalowicz M,
SummaryKarst aquifers are the main groundwater resource in Lebanon as well as in most Mediterranean countries. Most of them are not exploited in a sustainable way, partly because their characteristics remain unknown. Karst aquifers are so complex that the assessment of their resource and their exploitable storage requires an analysis of their whole functioning, particularly by analysing the spring hydrograph. Among all various methods, the method proposed by Mangin aims to characterize at the same time the recharge conditions and the storage and recession of the saturated zone by analyzing the spring hydrograph. This method defines two parameters, the infiltration delay i, and the regulating power k which are the roots of a classification of karst systems. This classification makes the distinction between karst and porous aquifers considering the value of the regulating power. k is assumed to be lower than 0.5 in karst, and between 0.5 and 1 for all other aquifers, 1 being the upper limit.The study of karst aquifers in Lebanon shows values of k > 0.5, and even 1; former data from the literature show that other karst springs in Middle East have comparable characteristics. In fact, what is not considered by Mangin and others, k is equivalent to a mean residence time in years of water in the saturated zone. So long residence times are normally observed in poorly karstified aquifers, or containing abandoned, not functioning karstification. The geological framework in which the studied springs are located in fact shows that these aquifers have been subject to a long, complex evolution, as a consequence of the base level rising. This rising produced the flooding of the successive karst drainage network, which does not really function anymore and provides a large storage capacity to the aquifer. The very interesting properties of these aquifers make them prime targets for fulfilling the increasing needs of water

Predicting travel times and transport characterization in karst conduits by analyzing tracer-breakthrough curves, , Morales Tomas, De Valderrama Inigo, Uriarte Jesus A. , Antiguedad Inaki, Olazar Martin,
SummaryThis paper analyzes data obtained in 26 tracer tests carried out in 11 karstic connections following solutional conduits in karst aquifers in the Basque Country. These conduits are preferential drainage pathways in these aquifers and so they confer a marked anisotropy and high vulnerability to them. Consequently, their consideration in protection and management studies and projects is a priority.The connections studied cover a wide hydrogeological spectrum (a wide range of sizes, slopes, geomorphic and hydrologic types) and the tests have been carried out at different hydrodynamic states. It is noteworthy that they all follow a similar trend, which has allowed for the development of a statistical approximation for the treatment of the whole information.Relationships have been established involving velocity, solute time of arrival, attenuation of peak concentration and time of passage of tracer cloud. These relationships are a valuable tool for management and supporting decision-making and allow for making estimates in connections in which the information available was scarce. This information is especially useful, given that the complexity of transport in karst conduits gives way to important deviations between real data (empirical observations) and the data obtained by simple approaches based on the Fickian-type diffusion equation

The Aggitis karst system, Eastern Macedonia, Greece: Hydrologic functioning and development of the karst structure, , Novel Jean Paul, Dimadi Agoro, Zervopoulou Anna, Bakalowicz Michel,
SummaryThe Aggitis karst system developed in the marbles of the Rhodope massif. The conditions of the development of its karst drainage network are determined from the geological and geomorphologic settings by means of a microstructural analysis, following Eraso's method. This analysis shows that the karst conduit network intensely developed in the western part of the mountain Falakro where the majority of the open fractures oriented in the same direction as the hydraulic gradient, while the two directions are perpendicular in its eastern part drained by the spring of Drama.The behaviour of the system was analysed by means of hydrodynamic and water geochemical techniques. Despite the extension of the cave system and of the favourable development conditions of conduits, the functioning appears complex, with a significant storage, and a slow infiltration as well as an easy drainage. On the contrary the Drama karst system, characterised by a low variability in its hydrological and geochemical characteristics does not show any karst functioning.In the Aggitis karst system the initial groundwater flow conditions in combination with the aperture planes of which the directions are in agreement with the hydraulic gradient, favoured the rapid development of a drainage network system. The recharge from a large surface catchment area on non-karstic rocks, through swallow holes in a wide polje contributed to increase the groundwater flow through the karst part of the system, facilitating the development of the conduits

Assessing the importance of conduit geometry and physical parameters in karst systems using the storm water management model (SWMM), , Peterson Eric W. , Wicks Carol M. ,
SummaryQuestions about the importance of conduit geometry and about the values of hydraulic parameters in controlling ground-water flow and solute transport through karstic aquifers have remained largely speculative. One goal of this project was to assess the role that the conduit geometry and the hydraulic parameters have on controlling transport dynamics within karstic aquifers. The storm water management model (SWMM) was applied to the Devil's Icebox-Connor's Cave System in central Missouri, USA. Simulations with incremental changes to conduit geometry or hydraulic parameters were performed with the output compared to a calibrated baseline model. Ten percent changes in the length or width of a conduit produced statistically significant different fluid flow responses. The model exhibited minimal sensitivity to slope and infiltration rates; however, slight changes in Manning's roughness coefficient can highly alter the simulated output.Traditionally, the difference in flow dynamics between karstified aquifers and porous media aquifers has led to the idea that modeling of karst aquifers is more difficult and less precise than modeling of porous media aquifers. When evaluated against models for porous media aquifers, SWMM produced results that were as accurate (10% error compared to basecase). In addition, SWMM has the advantage of providing data about local flow. While SWMM may be an appropriate modeling technique for some karstic aquifers, SWMM should not be viewed as a universal solution to modeling karst systems

A comparative integrated geophysical study of Horseshoe Chimney Cave, Colorado Bend State Park, Texas, , Brown Wesley A. , Stafford Kevin W. , Shawfaulkner Mindy , Grubbs Andy

An integrated geophysical study was performed over a known cave in Colorado Bend State Park (CBSP), Texas, where shallow karst features are common within the Ellenberger Limestone. Geophysical survey such as microgravity, ground penetrating radar (GPR), direct current (DC) resistivity, capacitively coupled (CC) resistivity, induced polarization (IP) and ground conductivity (GC) measurements were performed in an effort to distinguish which geophysical method worked most effectively and efficiently in detecting the presence of subsurface voids, caves and collapsed features. Horseshoe Chimney Cave (HCC), which is part of a larger network of cave systems, provides a good control environment for this research. A 50 x 50 meter grid, with 5 m spaced traverses was positioned around the entrance to HCC. Geophysical techniques listed above were used to collect geophysical data which were processed with the aid of commercial software packages. A traditional cave survey was conducted after geophysical data collection, to avoid any bias in initial data collection. The survey of the cave also provided ground truthing. Results indicate the microgravity followed by CC resistivity techniques worked most efficiently and were most cost effective, while the other methods showed varying levels of effectiveness.


Transport and variability of fecal bacteria in carbonate conglomerate aquifers, , Goeppert N. , Goldscheider N.

Clastic sedimentary rocks are generally considered non-karstifiable and thus less vulnerable to pathogen contamination than karst aquifers. However, dissolution phenomena have been observed in clastic carbonate conglomerates of the Subalpine Molasse zone of the northern Alps and other regions of Europe, indicating karstification and high vulnerability, which is currently not considered for source protection zoning. Therefore, a research program was established at the Hochgrat site (Austria/Germany), as a demonstration that karst-like characteristics, flow behavior and high vulnerability to microbial contamination are possible in this type of aquifer. The study included geomorphologic mapping, comparative multi-tracer tests with fluorescent dyes and bacteria-sized fluorescent microspheres, and analyses of fecal indicator bacteria (FIB) in spring waters during different seasons. Results demonstrate that (i) flow velocities in carbonate conglomerates are similar as in typical karst aquifers, often exceeding 100 m/h; (ii) microbial contaminants are rapidly transported towards springs; and (iii) the magnitude and seasonal pattern of FIB variability depends on the land use in the spring catchment and its altitude. Different ground water protection strategies than currently applied are consequently required in regions formed by karstified carbonatic clastic rocks, taking into account their high degree of heterogeneity and vulnerability.

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GHOST-ROCK KARSTIFICATION IN ENTRE-DEUX-MERS (GIRONDE, FRANCE), IMPLICATIONS FOR KARSTOGENESIS AND KARSTIC MORPHOLOGY, , Dubois Caroline, Lans Benjamin, Kaufmann Olivier, Maire Richard, Quinif Yves

The formation of the Oligocene « calcaires à Astéries » in the region of « Entre-deux-Mers » is affected by a karstification with subhorizontal caves that drained rivers from swallow-holes to resurgences. Observations in quarries show that ghost-rock alterites are present. This paper describes the ghost-rocks in the quarry of Piquepoche exploiting the Frontenac stone. We have studied horizontally developed ghost-rocks with vertical extensions still containing the residual alterite. They can be badly consolidated calcarenites up to soft material which has been sampled. Speleogenesis is reviewed in the frame of the mechanical erosion of the alterite of a horizontal ghost-rock followed by an incision by free-flowing waters which form a passage with promontories and potholes. Finally, we show that ceiling anastomoses can form by ghost-rock karstification.


A New Equation Solver for Modeling Turbulent Flow in Coupled Matrix‐Conduit Flow Models, ,

Karst aquifers represent dual flow systems consisting of a highly conductive conduit system embedded in a less permeable rock matrix. Hybrid models iteratively coupling both flow systems generally consume much time, especially because of the nonlinearity of turbulent conduit flow. To reduce calculation times compared to those of existing approaches, a new iterative equation solver for the conduit system is developed based on an approximated Newton–Raphson expression and a Gauß–Seidel or successive over-relaxation scheme with a single iteration step at the innermost level. It is implemented and tested in the research code CAVE but should be easily adaptable to similar models such as the Conduit Flow Process for MODFLOW-2005. It substantially reduces the computational effort as demonstrated by steady-state benchmark scenarios as well as by transient karst genesis simulations. Water balance errors are found to be acceptable in most of the test cases. However, the performance and accuracy may deteriorate under unfavorable conditions such as sudden, strong changes of the flow field at some stages of the karst genesis simulations.

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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

Unusual speleothems resembling giant mushrooms occur in Cueva Grande de Santa
Catalina, Cuba. Although these mineral buildups are considered a natural heritage, their
composition and formation mechanism remain poorly understood. Here we characterize
their morphology and mineralogy and present a model for their genesis. We propose that
the mushrooms, which are mainly comprised of calcite and aragonite, formed during four
different phases within an evolving cave environment. The stipe of the mushroom is an
assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts
that were subsequently encrusted by cave clouds (mammillaries). More peculiar is the
cap of the mushroom, which is morphologically similar to cerebroid stromatolites and
thrombolites of microbial origin occurring in marine environments. Scanning electron
microscopy (SEM) investigations of this last unit revealed the presence of fossilized
extracellular polymeric substances (EPS)—the constituents of biofilms and microbial
mats. These organic microstructures are mineralized with Ca-carbonate, suggesting that
the mushroom cap formed through a microbially-influenced mineralization process. The
existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence
of phototrophs) has interesting implications for the study of fossil microbialites preserved
in ancient rocks, which are today considered as one of the earliest evidence for life on
Earth.


On the Geology of the Western States of North America, 0000, Owen David Dale,
The remarks here submitted will be confined chiefly to that part of the Western States of North America watered by the rivers Ohio, Wabash, Illinois, Rock, Wisconsin, Cumberland and Tennessee, lying between the 35th and 43rd degree of N. latitude and the 81st and 91st of W. longitude. The district includes the states of Illinois, Indiana, Ohio, Kentucky, Tennessee, and the Du Buque and Mineral Point districts of Iowa and Wisconsin. This territory occupies an area of about half a million of square miles, but its geological features are remarkably uniform, belonging, with a few partial exceptions, to the periods of the bituminous coal and carboniferous limestone as found in Europe, and the Silurian rocks as described by Sir R. Murchison; the exceptions are the superficial deposits which occasionally cover up these from view over considerable tracts, and these must either be referred to the age of gigantic mammalia and formations of a much newer date, or belong to a marl and greensand found in the western district of Tennessee, probably a portion of the greensand and other members of the cretaceous group. A general idea of the geological formations of the whole tract may be obtained from the annexed diagram. ... This 250-word extract was created in the absence of an abstract

The cycle of subterranean drainage as illustrated in the Bloomington Quadrangle (Indiana), 1911, Beede J. W.

Ein interessanter Fund in der Hhle im ''Blauen Bruch'' im Leithagebirge., 1950, Anonym,
[(2911/5), Pferde, Bronzpfeilspitze]

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