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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 density current is a gravity-induced flow of one current through, over, or under another, owing to density differences. factors affecting density differences include temperature, salinity, and concentration of suspended particles.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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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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Featured articles from other Geoscience Journals
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 co2 concentration (Keyword) returned 33 results for the whole karstbase:
Showing 1 to 15 of 33
RECOGNITION OF MICROCLIMATE ZONES THROUGH RADON MAPPING, LECHUGUILLA CAVE, CARLSBAD-CAVERNS-NATIONAL-PARK, NEW-MEXICO, 1991, Cunningham Ki, Larock Ej,
Radon concentrations range from < 185 to 3,515 Bq m-3 throughout Lechuguilla Cave, Carlsbad Caverns National Park, New Mexico. Concentrations in the entrance passages and areas immediately adjacent to these passages are controlled by outside air temperature and barometric pressure, similar to other Type 2 caves. Most of the cave is developed in three geographic branches beneath the entrance passages; these areas maintain Rn levels independent of surface effects, an indication that Rn levels in deep, complex caves or mines cannot be simply estimated by outside atmospheric parameters. These deeper, more isolated areas are subject to convective ventilation driven by temperature differences along the 477-m vertical extent of the cave. Radon concentrations are used to delineate six microclimate zones (air circulation cells) throughout the cave in conjunction with observed airflow data. Suspected surface connections contribute fresh air to remote cave areas demonstrated by anomalous Rn lows surrounded by higher values, the presence of mammalian skeletal remains, CO2 concentrations and temperatures lower than the cave mean, and associated surficial karst features

Activity od the scientific commission of ''Grotta Grande del Vento'' (Genga, Ancona, Central Italy)., 1994, Bertolani Mario, Cigna Arrigo A.
The Grotta Grande del Vento (the Great Wind Cave) was discovered in 1971. An administrative body (the "Consorzio Frasassi") under the control of some local authorities took care of its development and the cave was opened to tourists in 1974. A Scientific Commission formed by some experts (choosen by the Consorzio Frasassi) of different disciplines was established in 1975. During these 15 years the Commission acted as an advisory committee for the Consorzio in order to guarantee the protection of the cave environment. In particular the Commission set up a monitoring network of the most important environmental parameters (air and water temperature. air currents, relative humidity and CO2 concentration) in some suitable locations and studied the best solutions to avoid algae and other plants proliferation in the vicinity of light sources. The Commission promoted and directed researches in the karst system under a strict co-operation with the Consorzio Frasassi which funded most of them. Some scientific papers resulted from these researches.

Influence of Pedo-chemical Field on Epi-karstification in Subtropical Humid Region-Field Monitoring and Laboratory Experiment , 1998, Pan Genxing, Tao Yuxiang, Teng Yogzhong, Xu Shenyou, Sun Yuhua, Han Fushun

The influence of pedo-chemical conditions on epi-karstification in a karst hydrogeochemical experiment site near Guilin was studied. The dissolution of limestone, and pH, CO2, HCO3- in soil and karst water under soil cover conditions was monitored by using filter tubes containing reference rock plate, and by using portable pH meter, CO2 gas meter and Aqumerck Kit. Laboratory experiments of dissolution under different soil conditions were also conducted by using leaching cylinders. In addition, 13C tracing was carried out on the samples of plant- litter- SOM-soil CO2-spring water-travertine-rock in the karst system. Soil pH, SOM status (subsequently CO2 concentration) and Ca+2 saturation constitutes a pedo-chemical field vigorously affecting the rock dissolution. The carbon in the form of HCO3- in the spring water and of CaCO3 in the travertine was closely related with the soil CO2 gas. Thus, soil carbon through the transferring pathway of air CO2-plant carbon-SOC-soil CO2 was involved in the epi-karstification process, and interface exchange of soil Ca+2, HCO3- with karst water existed in the karst hydrogeochemical flow. A modified model for epi-karstification in the studied area was suggested.


Microclimate Study of Kartchner Caverns, Arizona, 1999, Buecher, R. H.
A detailed two-year study of the microclimate in Kartchner Caverns determined that the most significant problem in maintaining the microclimate of the cave is the potential for drying out due to increased airflow. Two factorsa small, hypothesized upper second entrance and a slight geothermal warming of the cavecontrol natural airflow and increase the amount and intensity of winter air exchange. The average amount of water reaching the cave is 7.9 mm/yr, only twice the amount lost by evaporation from cave surfaces. Kartchner Caverns has an average relative humidity (RH) of 99.4%. Useful measurement of RH required a dewpoint soil psychrometer rather than a sling psychrometer. Moisture loss from cave surfaces is proportional to relative humidity, and small changes in RH have a dramatic effect on evaporation from cave surfaces. A lowering of RH to 98.7% would double the evaporation rate and start to dry out the cave. The volume of air exchange in the cave was estimated from direct measurement, changes in CO2 concentration, and temperature profile models. All of these methods are consistent with a volume of 4,000 m/day entering the cave during the winter. During the summer, the direction of airflow reverses and the volume of air leaving the cave is much smaller than during the winter months. Surface air is almost always drier than cave aironly during the summer months when rain occurs does outside air contain more moisture. However, the rate of air exchange is greatly reduced during the summer, which minimizes any potential effect of increased outside moisture. Radon concentrations in the cave are high enough to be of concern for long-time employees but not for the general public. Radon222 concentrations average 90 pCi/L and radon daughters average 0.77 Working Levels (WL) in the main part of the cave. During the winter, radon levels in the Echo Passage are up to six times higher than the rest of the cave due to the passages stable microclimate and limited air movement, which greatly reduces radon removal by plateout. Natural removal by ventilation is only a minor factor in determining radon levels in the rest of the cave.

CO2 source-sink in karst processes in karst areas of China, 1999, Jiang Z. C. , Yuan D. X. ,
The CO2 source-sink of atmospheric greenhouse has a close relationship with karst processes. The corrosion of carbonate rocks lends to the sink of atmospheric CO2, whereas the deposition of carbonate rocks gives off CO2 into atmosphere, which is one of the sources of atmospheric CO2. According to the exposed areas of carbonate rocks in China, the flux of atmospheric CO2 consumed in karst processes is estimated at about 1.77 x 10(13) g CO2/a, Considering the global karst area the flux Of atmospheric CO2 consumed in corrosion may be an important parr of the missing sink. And the sink has a tendency of continuous increase. The release of CO2 from karst water is usually less than the sink of atmospheric CO2 consumed in karst processes. But in active tectonic zone the release of high CO2 concentration of mantle source in the geothermal karst water should not be neglected

Role of mixing corrosion in calcite-aggressive H2O-CO2-CaCO3 solutions in the early evolution of karst aquifers in limestone, 2000, Gabrovsek F, Dreybrodt W,
Two cave-forming mechanisms in limestone are discussed currently. First, when two H2O-CO2-CaCO3 solutions, saturated with respect to calcite but with different chemical compositions mix, renewed aggressiveness to limestone dissolution occurs. This process called mixing corrosion [Bogli, 1964, 1980], in combination with linear dissolution kinetics, has been suggested as cave forming. Second, it has been shown that solely the action of nonlinear dissolution kinetics can generate extended karst conduits. This paper combines both mechanisms. By digital modeling of the evolution of the aperture widths of a confluence of two fractures into a third one it is shown that the first mechanism does not create large cave conduits. The combination of mixing corrosion and nonlinear kinetics, however, considerably intensifies karstification, compared to that of nonlinear kinetics solely. The times to terminate early evolution of karst are significantly reduced when the CO2 concentrations of the inflowing solutions differ by no more than 30%. We discuss the underlying mechanisms by inspection of the time dependence of the evolution of aperture widths, flow rates through them, and of the renewed undersaturation of the mixed solution at the confluence of two fractures. Finally, the evolution of a karst aquifer on a two-dimensional percolation network is modeled when mixing corrosion is present, and compared to that on an identical net with identical nonlinear dissolution kinetics, but mixing corrosion excluded. Large differences in the morphology of the net of cave conduits are found and also a reduction of the time of their evolution. From these findings we conclude that climatic changes, which influence the p(CO2) in the soil, can divert the evolving cave patterns

Equilibrium chemistry of karst water in limestone terranes, 2000, Dreybrodt W.
This chapter summarizes the equilibria of the chemical reactions occurring in CaCO3 - H2O - CO2 solutions, as they are typical for karst water. The evolution of the chemical composition of such solutions during their interaction with limestone depends on specific geological conditions, such as dissolution proceeding under the conditions of the open or closed system with respect to CO2. Since the CO2 concentration in karst water determines its further chemical evolution and the equilibrium concentration of Ca 2+ with respect to calcite in all cases of interest, equations are derived which describe the evolution of the chemical composition in the most general case, i.e. when a limited volume of gaseous CO2 is in contact with a solution dissolving limestone. This includes the cases of open and closed system with respect to CO2 as end members. Finally we discuss the influence of foreign ions common in karst, such as Mg 2+, SO4 2-, Na + and Cl - to the equilibrium concentration of dissolved Ca 2+ ions with respect to calcite.

Soil carbon dioxide in a summer-dry subalpine karst, Marble Mountains, California, USA, 2001, Davis J, Amato P, Kiefer R,
Studies of the seasonality, spatial variation and geomorphic effects of Soil CO2 concentrations in a summer-dry subalpine karst landscape in the Marble Mountains, Klamath National Forest, California, demonstrate the significance of soil moisture as a limiting factor. Modeled actual evapotranspiration (AET) in the four weeks prior to sampling explains 36% of the observed soil-CO2 concentrations, pointing to the importance of root respiration processes in these systems. Late snows are significant in controlling the timing of a snowmelt-initiated pulse of respiration and groundwater. CO2 concentrations were measured at multiple sites in two seasons - 1995 and 1997 - with contrasting patterns of snowmelt. Other than wet-meadow anomalies, where CO2 concentrations reached up to 3.8% in midsummer, alpine meadows on schist were the sites of the highest spring peak concentrations of approximately 1%. Forest sites and sites with thin soils on marble typically peaked at approximately 0.5%, also within a month of snowmelt exposure. Ongoing karstification in the upper bare karst is focused in soil-filled grikes where late-season snowmelt concentrates flow during high-respiration periods, but the lack of active speleothem development suggests that the carbonate solution system is greatly reduced from preglacial periods

CONTROL OF ENVIRONMENTAL PARAMETERS FOR MANAGEMENT AND CONSERVATION OF NERJA CAVE (MALAGA, SPAIN), 2002, Carrasco Francisco, Vadillo Iñ, Aki, Liñ, á, N Cristina, Andreo Bartolomé, , Durá, N Juan José,

The Nerja Cave receives on average more than 500,000 visitors per year. In order to know the possible impact in the underground environment by human visits, a monitoring network was installed since 1993, to control hourly several parameters. Also, since 1991 a hydrochemical control has been carried out in the drip water points of the cave and in the natural discharge points of the carbonate aquifer. This continuous record of physical-chemical parameters of drip water, its daily outflow, as well as temperature and relative humidity in the air, CO2 concentration and rock temperature shows the human influence. The main changes in environmental parameters are the following: 1. cave air temperature rises 0.2 °C by 1000 visitors/day; 2. a daily increase between 2 and 3 % in relative air humidity, reaching saturation on summer days; 3. CO2 concentration in air increases up to values between 500 and 700 ppm during low visitability periods and 10 times the background value during high visitability periods (2.800 ppm); 4. temperature of the rock rises between 0.02 °C and 0.15 °C/day, and (5) PCO2 of drip water also presents variations, increasing during the big influx of visits and decreasing the saturation index of carbonated minerals.


Study of soil leachates in doline above the Beke Cave, Hungary, 2004, Tatar E. , Mihucz V. G. , Tompa K. , Poppl L. , Zaray G. , Zambo L. ,
Fulvic acid, Ca and Mg concentrations as well as dissolved inorganic carbon (DIC), pH and electric conductivity values of soil solutions which resulted from injecting bidistilled water onto glass columns filled with different soils (black rendzina, brown rendzina, red clayey rendzina, red clay) characteristic of the Aggtelek karst system (NE Hungary), were determined. Identification and determination of fulvic acid were achieved by size exclusion chromatography (SEC) and adsorption chromatography, respectively, with fluorescent spectrometric detection. The Ca and Mg concentration of the samples was determined by applying an inductively coupled plasma atomic emission spectrometric (ICP-AES) method. DIC-expressed in CO2 concentration values-was determined by using a CO2 selective electrode. According to the SEC analysis, the apparent molecular weight of the fulvic acids of the samples were between 500 and 1600 Da. The fulvic acid concentration values of the percolated water samples decreased in function of the soils investigated as follows: black rendzina>brown rendzina>red clayey rendzina>red clay, which is in concordance with the organic matter content of these types of soils. The results obtained for fulvic acid, Ca and Mg concentrations as well as for DIC, pH and electric conductivity of the water samples collected from the column filled with red clay were in good agreement with those of a seepage water sample collected from an observation station built in red clay above the Beke Cave (Aggtelek). Since the artificially prepared red clay column was exposed to the same temperature and humidity conditions like red clay of the sampling site, this method seems to be suitable for modelling infiltration of fulvic acid and metals from red clay into seepage water under laboratory conditions. (C) 2003 Elsevier B.V. All rights reserved

Hydrochemical variations during flood pulses in the south-west China peak cluster karst: impacts of CaCO3-H2O-CO2 interactions, 2004, Liu Z. H. , Groves C. , Yuan D. X. , Meiman J. , Jiang G. H. , He S. Y. , Li Q. A. ,
High-resolution measurements of rainfall, water level, pH, conductivity, temperature and carbonate chemistry parameters of groundwater at two adjacent locations within the peak cluster karst of the Guilin Karst Experimental Site in Guangxi Province, China, were made with different types of multiparameter sonde. The data were stored using data loggers recording with 2 min or 15 min resolution. Waters from a large, perennial spring represent the exit for the aquifer's conduit flow, and a nearby well measures water in the conduit-adjacent, fractured media. During flood pulses, the pH of the conduit flow water rises as the conductivity falls. In contrast, and at the same time, the pH of groundwater in the fractures drops, as conductivity rises. As Ca2 and HCO3- were the dominant (>90%) ions, we developed linear relationships (both r(2) > 0.91) between conductivity and those ions, respectively, and in turn calculated variations in the calcite saturation index (SIc) and CO2 partial pressure (PCO2) of water during flood pulses. Results indicate that the PCO2 of fracture water during flood periods is higher than that at lower flows, and its SIc is lower. Simultaneously, PCO2 of conduit water during the flood period is lower than that at lower flows, and its SIc also is lower. From these results we conclude that at least two key processes are controlling hydrochemical variations during flood periods: (i) dilution by precipitation and (ii) water-rock-gas interactions. To explain hydrochemical variations in the fracture water, the water-rock-gas interactions may be more important. For example, during flood periods, soil gas with high CO2 concentrations dissolves in water and enters the fracture system, the water, which in turn has become more highly undersaturated, dissolves more limestone, and the conductivity increases. Dilution of rainfall is more important in controlling hydrochemical variations of conduit water, because rainfall with higher pH (in this area apparently owing to interaction with limestone dust in the lower atmosphere) and low conductivity travels through the conduit system rapidly. These results illustrate that to understand the hydrochemical variations in karst systems, considering only water-rock interactions is not sufficient, and the variable effects of CO2 on the system should be evaluated. Consideration of water-rock-gas interactions is thus a must in understanding variations in karst hydrochemistry. Copyright (C) 2004 John Wiley Sons, Ltd

Anthropogenic CO2-flux into cave atmosphere and its environmental impact: A case study in the Cisarska Cave (Moravian Karst, Czech Republic), 2006, Faimon J, Stelcl J, Sas D,
The evolution of CO2 levels was studied in the ventilated and unventilated Nagel Dome chamber (the Cisarska Cave) with- and without human presence. Based on a simplified dynamic model and CO2/Rn data (222Rn considered as a conservative tracer), two types of CO2-fluxes into the chamber were distinguished: (1) the natural input of (2-4) x 10- 6[no-break space]m3 s- 1, corresponding to a flux of (8.5-17) x 10- 10[no-break space]m3 m- 2 s- 1 and (2) an anthropogenic input of (0.6-2.5) x 10- 4[no-break space]m3 s- 1, corresponding to an average partial flux of (4.8-7.7) x 10- 6[no-break space]m3 s- 1 person- 1. The chamber ventilation rates were calculated in the range from 0.033 to 0.155[no-break space]h- 1. Comparison of the chamber CO2-levels with chamber dripwater chemistry indicates that the peak CO2-concentrations during stay of persons (log pCO2 ~ - 2.97, - 2.89, and - 2.83) do not reach the theoretical values at which dripwater carbonate species and air CO2 are at equilibrium (log pCO2[DW] ~ - 2.76 to - 2.79). This means that CO2-degassing of the dripwaters will continue, increasing supersaturation with respect to calcite (dripwater saturation index defined as SIcalcite = aCa2? / 10- 8.4 varied in the range from 0.76 to 0.86). The pCO2[DW] values, however, would easily be exceeded if the period of person stay in the chamber had been slightly extended (from 2.85 to 4[no-break space]h under given conditions). In such case, the dripwater CO2-degassing would be inverted into CO2-dissolution and dripwater supersaturation would decrease. Achieving the threshold values at which water become aggressive to calcite (log pCO2[EK] ~ - 1.99, - 2.02, and - 1.84) would require extreme conditions, e.g., simultaneous presence of 100 persons in the cave chamber for 14[no-break space]h. The study should contribute to a better preservation of cave environment

Seasonal Variations in Modern Speleothem Calcite Growth in Central Texas, U.S.A, 2007, Banner Jl, Guilfoyle A, James Ew, Stern La, Musgrove M,
Variations in growth rates of speleothem calcite have been hypothesized to reflect changes in a range of paleoenvironmental variables, including atmospheric temperature and precipitation, drip-water composition, and the rate of soil CO2 delivery to the subsurface. To test these hypotheses, we quantified growth rates of modern speleothem calcite on artificial substrates and monitored concurrent environmental conditions in three caves across the Edwards Plateau in central Texas. Within each of two caves, different drip sites exhibit similar annual cycles in calcite growth rates, even though there are large differences between the mean growth rates at the sites. The growth-rate cycles inversely correlate to seasonal changes in regional air temperature outside the caves, with near-zero growth rates during the warmest summer months, and peak growth rates in fall through spring. Drip sites from caves 130 km apart exhibit similar temporal patterns in calcite growth rate, indicating a controlling mechanism on at least this distance. The seasonal variations in calcite growth rate can be accounted for by a primary control by regional temperature effects on ventilation of cave-air CO2 concentrations and/or drip-water CO2 contents. In contrast, site-to-site differences in the magnitude of calcite growth rates within an individual cave appear to be controlled principally by differences in drip rate. A secondary control by drip rate on the growth rate temporal variations is suggested by interannual variations. No calcite growth was observed in the third cave, which has relatively high values of and small seasonal changes in cave-air CO2. These results indicate that growth-rate variations in ancient speleothems may serve as a paleoenvironmental proxy with seasonal resolution. By applying this approach of monitoring the modern system, speleothem growth rate and geochemical proxies for paleoenvironmental change may be evaluated and calibrated

Carbon dioxide concentration in air within the Nerja Cave (Malaga, Andalusia, Spain), 2008, Lin C. , Vadillo I. And Carrasco F.
From 2001 to 2005 the CO2 concentration of the air in the interior and exterior of the Nerja Cave was studied and its relation with the air temperature and visitor number. The average annual CO2 concentration outside of the cave is 320 ppmv, whilst inside, the mean concentration increases to 525 ppmv during autumn and winter, and in the order of 750 ppmv during spring and summer. The temporal variation of CO2 content in the air of the cave is strongly influenced by its degree of natural ventilation which is, in turn, determined by the difference between external and internal air temperatures. During autumn, winter and spring, a positive correlation between the CO2 content of the air inside the cave and the temperature difference between the external and internal air was observed, such that when this difference increased, there was a higher level of CO2 within the cave. Then, the ventilation is high and CO2 levels are mainly of human origin. During summer, there was a negative correlation between CO2 and the temperature difference between the air outside and that inside the cave: when the temperature difference increases, the CO2 content within the cave is lower. At this time of the year, the renovation of the air is much slower due to the lower ventilation. A positive correlation between CO2 concentration of the air in the cave and the visitor number can only be observed during August, the month that receives the most visits throughout the year averaging 100,000.

Palaeoclimate Research in Villars Cave (Dordogne, SW-France)., 2008, Genty D.
Villars Cave is a typical shallow cave from South-West France (45.44N; 0.78E; 175 m asl) that has provided several speleothem palaeoclimatic records such as the millennial scale variability of the Last Glacial period and the Last Deglaciation. Monitoring the Villars cave environment over a 13-year period has helped in the understanding of the stable isotopic speleothem content and in the hydrology. For example, it was demonstrated that most of the calcite CaCO3 carbon comes from the soil CO2, which explains the sensitivity of the ?13C to any vegetation and climatic changes. Drip rate monitoring, carried out under four stalactites from the lower and upper galleries, has shown a well marked seasonality of the seepage water with high flow rates during winter and spring. A time delay of about two months is observed between the water excess (estimated from outside meteorological stations) and the drip rate in the cave. A great heterogeneity in the flow rate amplitude variations and in the annual quantity of water between two nearby stalactites is observed, confirming the complexity of the micro-fissure network system in the unsaturated zone. At a daily scale, the air pressure and drip rates are anti-correlated probably because of pressure stress on the fissure network. Cave air CO2 concentration follows soil CO2 production and is correlated with its ?13C content. Since the beginning of the monitoring, the cave air temperature, in both lower and upper galleries, displays a warming trend of ~+0.4C0.1/10yrs. This might be the consequence of the outside temperature increase that reaches the Villars Cave galleries through thermal wave conduction. Chemistry monitoring over a few years has shown that the seepage water of the lower gallery stations is significantly more concentrated in trace and minor elements (i.e. Sr, Mg, Ba, U) than the upper stations, probably due to the 10-20 m depth difference between these galleries, which implies a different seepage pathway and different water/rock interaction durations. There is also, in the elemental concentration (i.e. [Ca]), a seasonal signal which causes variation in the speleothem growth rates. Modern calcite deposit experiments conducted for several years have permitted the calculation of vertical growth rates, which are extremely high in Villars (i.e. 1.0 to 1.75 mm/ yr). Pollen filter experiments in the cave have demonstrated that most of the pollen grain found in the cave comes from the air and not from the water. The specificity of the Villars Cave records is that the climatic variations were well recorded in the calcite ?13C whereas the ?18O is usually used in such studies. Overall, these results are helpful for the interpretation of speleothem records for palaeoclimatic reconstructions, but more work is needed, especially numerical modelling of the temperature, chemistry and hydrology.

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