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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 rockfall is the falling of bedrock from a cliff or steep slope [16].?

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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 ventilation (Keyword) returned 26 results for the whole karstbase:
Showing 1 to 15 of 26
Cave-Air for Ventilation, 0000, Leonard W. H. ,

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

Subterranean Waterworks of Biblical Jerusalem: Adaptation of a Karst System, 1991, Gill Dan,
Ancient Jerusalem has long been known to possess a system of subterranean waterworks by which the spring of Gihon, which issues outside the walls, could be approached from within the city, and its waters diverted to an intramural pool. Most scholars regarded these waterworks as man-made, but the techniques of underground orientation and ventilation employed by the builders, as well as the numerous anomalies and ostensible mistakes in design, mystified investigators. Geological investigation has revealed the waterworks to be part of a well-developed karst system, a network of natural dissolution channels and shafts, in the limestone and dolomite underlying the city. Thus, it was not through primary planning but by means of skillful adaptation of these pre-existing natural features that the city was ensured of a dependable water supply during both war and peace. Likewise, knowledge of the subterranean access may have played a role in David's capture of the Jebusite city

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.

Radon concentration changes in the air of two caves in Poland, 1999, Przylibski T. A. ,
The paper presents spatial and seasonal radon concentration changes in the air of two caves in Poland on the basis of measurements during 1995-1997. A process of seasonal radon concentration changes in the caves' air was identified, based on research on radon occurrence in caves carried out for over 20 years. A major role in this process was ascribed to ventilation caused by atmospheric temperature changes. High radon concentrations are observed in the warm half-year (May-August), when the average air temperature exceeds the average temperature of the cave interior. Low concentrations occur, however, in the cold half-year (December-January), and a relatively sharp increase or decrease in radon concentration is related to changes in atmospheric temperatures relative to the average temperature in the cave interior. The amplitude of these radon concentration changes may reach several kBq m(-3). In the Radochowska Cave the lowest monthly radon concentration (0.06 kBq m(-3)) was recorded in December 1996, while the highest (1.37 kBq m(-3)) was observed in August 1996. In the Niedzwiedzia Cave the lowest value (0.10 kBq m(-3)) was observed in January 1997 and the highest (4.18 kBq m(-3)) was noted in March 1997. The spatial variation of radon concentrations is mainly due to the morphology of the chambers and corridors of a cave, and by the distance between the measurement point and the entrance holes. As a rule, locations further from the entrance have poorer ventilation and higher radon concentrations. (C) 1999 Elsevier Science Ltd. All rights reserved

The relationship between local climate and radon concentration in the Temple of Baal, Jenolan Caves, Australia, 2003, Whittlestone Stewart , James Julia , Barnes Craig
Radon measurements were collected over a period of one year in a large chamber known as the Temple of Baal at Jenolan Caves, near Sydney, Australia. Correlation of radon concentrations with rainfall, surface air pressure and temperature confirmed that radon originating from different locations was predominant under different conditions. During periods of low rainfall, radon concentrations varied in strong anti-correlation with the surface air pressure, indicating that most of the radon was coming from remote locations of large pore or void volume in rock of limited permeability. On the other hand, in wet periods the observed radon levels were low and steady, suggesting a local source. In both wet and dry conditions the correlation of radon concentrations with rainfall on a time-scale of a few days was positive, proving that permeability of surface strata affected the ventilation rate in the cave. The study achieved a detailed understanding of radon concentrations in the Temple of Baal, and the main conclusion reached was that the magnitude and variation of radon concentrations in the Temple of Baal were closely related to the degree of water saturation in the local surrounds.

The relationship between local climate and radon concentration in the Temple of Baal, Jenolan Caves, Australia, 2003, Whittlestone Stewart , James Julia, Barnes Craig

Radon measurements were collected over a period of one year in a large chamber known as the Temple of Baal at Jenolan Caves, near Sydney, Australia. Correlation of radon concentrations with rainfall, surface air pressure and temperature confirmed that radon originating from different locations was predominant under different conditions. During periods of low rainfall, radon concentrations varied in strong anti-correlation with the surface air pressure, indicating that most of the radon was coming from remote locations of large pore or void volume in rock of limited permeability. On the other hand, in wet periods the observed radon levels were low and steady, suggesting a local source. In both wet and dry conditions the correlation of radon concentrations with rainfall on a time-scale of a few days was positive, proving that permeability of surface strata affected the ventilation rate in the cave. The study achieved a detailed understanding of radon concentrations in the Temple of Baal, and the main conclusion reached was that the magnitude and variation of radon concentrations in the Temple of Baal were closely related to the degree of water saturation in the local surrounds.


Cryogenic cave calcite from several Central European caves: age, carbon and oxygen isotopes and a genetic model, 2004, Zak Karel, Urban Jan, Cilek Vaclav, Hercman Helena,
Cryogenic cave calcite (CCC), formed by segregation of solutes during water freezing, was found in three Central European caves. This calcite type forms accumulations of loose calcite grains on cave floor. The calcite grains are of highly variable crystal morphology, and of sizes ranging from less than 1 mm to over 1 cm. The most typical feature is their accumulation as loose (uncemented) crystals. U-series dating indicates the formation of CCC in the studied caves during several climatic oscillations of the Weichselian (between 61 and 36 ka BP in the Chelsiowa Jama-Jaskinia Jaworznicka cave system in Poland, between 34 and 26 ka BP in the BUML Cave in the Czech Republic, and between 26 and 21 ka BP in the Stratenska Jaskyna cave system, Slovakia). At the time of CCC formation, the studied caves were lying in a periglacial zone.Detailed C and O stable isotope study of CCC samples revealed that slow water freezing under isotope equilibrium was the dominant formational process in the studied Polish and Czech caves. Significantly higher [delta]13C values of CCC in the Stratenska Jaskyna Cave indicate either water freezing in a more opened system with continuous CO2 escape (Rayleigh fractional separation), or participation of another CO2 source. The model of slow water freezing under isotope equilibrium is supported by isolated character of the caves having limited ventilation.In contrast, modern cryogenic cave calcite powders sampled directly on the ice surface of two recently iced caves in Slovakia with high ventilation showed much higher [delta]18O and [delta]13C data, similar to cryogenic calcites obtained in experimental rapid water freezing

14C Activity and Global Carbon Cycle Changes over the Past 50,000 Years, 2004, Hughen K. , Lehman S. , Southon J. , Overpeck J. , Marchal O. , Herring C. , Turnbull J. ,
A series of 14C measurements in Ocean Drilling Program cores from the tropical Cariaco Basin, which have been correlated to the annual-layer counted chronology for the Greenland Ice Sheet Project 2 (GISP2) ice core, provides a high-resolution calibration of the radiocarbon time scale back to 50,000 years before the present. Independent radiometric dating of events correlated to GISP2 suggests that the calibration is accurate. Reconstructed 14C activities varied substantially during the last glacial period, including sharp peaks synchronous with the Laschamp and Mono Lake geomagnetic field intensity minimal and cosmogenic nuclide peaks in ice cores and marine sediments. Simulations with a geochemical box model suggest that much of the variability can be explained by geomagnetically modulated changes in 14C production rate together with plausible changes in deep-ocean ventilation and the global carbon cycle during glaciation

Prediction of condensation in caves, 2005, Defreitas C. R. , Schmekal A.

Condensation is an important process in karst environments, especially in caves where carbon dioxide enriched air can lead to high rates of condensation corrosion. The problem is there has been very little research reported in the literature dealing with condensation as a microclimate process. This study addresses the problem and reports on a method for measuring and predicting condensation rates in a limestone cave. Electronic sensors for measuring condensation and evaporation of the condensate as part of a single continuous process of water vapour flux are tested and used to collect 12 months of data. The study site is the Glowworm tourist cave in New Zealand. Condensation is a function of the vapour gradient between rock surfaces in the cave and cave air. The size of the gradient is largely determined by air exchange with the outside. The results show that the numerical model to predict condensation works well. Given that rock-surface temperature in the cave does not vary much, condensation is essentially a function of cave air temperature and the processes that affect it, mainly, air exchange with outside. The results show that condensation can be controlled by controlling ventilation of the cave.


Carbon dioxide sources, sinks, and spatial variability in shallow temperate zone caves: Evidence from Ballynamintra Cave, Ireland., 2006, Baldini J. U. L. , Baldini L. M. , Mcdermott F. , Clipson N.
Carbon dioxide concentrations in Ballynamintra Cave, S. Ireland, generally increase with distance from the entrance, but this trend is non-linear because physical constrictions and slope changes compartmentalize the cave into zones with distinct Pco2 signatures. In this cave, CO2 originates from the soil and enters the cave by degassing from drip-water and by seeping through fractures, and is then transported throughout the cave by advection. Elevated concentrations in roof fissures, joints, and adjacent to vails suggest that these locations shelter CO2 gas from advection and permit local accumulation. CO2 enrichment was noted over a sediment accumulation, suggesting that microbial oxidation of organic compounds in the sediment provided an additional CO2 source distinct from the soil zone above the cave. Advection driven by external barometric pressure variations caused ventilation, which is the principal CO2 sink. The data presented here underscore the need for high resolution data to adequately characterize cave air Pco2 variability.

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.

Carbon dioxide concentration in air within the Nerja Cave (Malaga, Andalusia, Spain)., 2008, Lin C. , Vadillo I. , 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.


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