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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 decoration is cave features due to secondary precipitation of calcite, aragonite, gypsum, and other rarer minerals.?

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KarstBase a bibliography database in karst and cave science.

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 lag time (Keyword) returned 6 results for the whole karstbase:
Variation of Hardness in Cave Drips at Two Tasmanian Sites, 1981, Goede, Albert

Thirteen consecutive monthly samples were collected from two drip sites at each of two Tasmanian caves: Little Trimmer at Mole Creek and Frankcombe Cave in the Florentine Valley. At one of the two drip sites in Little Trimmer a positive relationship was found between the logarithm of precipitation and the total hardness without any detectable lag effect. No such relationship was detected at the other drip site despite its close proximity. At both drip sites the hardness values fail to show a seasonal pattern and are clearly unrelated to surface temperature variations. In strong contrast both drip sites in Frankcombe Cave showed significant seasonal variation and close positive correlation with mean monthly temperature with lag times of one and two months respectively. At one of the two drip sites the influence of monthly precipitation on variations in drip hardness could also be detected. The strong temperature dependence of cave drip hardness values at these sites may well be due to soil exposure to direct insolation following recent clearfelling and burning of vegetation in the area.

An examination of short-term variations in water quality at a karst spring in Kentucky, 1996, Ryan M. , Meiman J. ,
Water quality at many karst springs undergoes very high amplitude but relatively brief degradation following influxes of runoff. Accurately recording transient variations requires more rigorous sampling strategies than traditional methods, A pilot study to determine the usefulness of high-frequency, flow-dependent sampling strategies, combined with coincidental quantitative dye tracer tests, was implemented in the Big Spring Ground-Water Basin in Mammoth Cave National Park, Kentucky. Data recorded following two separate runoff events showed that the concentrations of two nonpoint source pollutants, fecal coliform bacteria and suspended sediment, greatly exceeded prerunoff event values for very short periods of time, A phreatic conduit segment, calculated at 17 million liters in volume, instantaneously propagated head changes, caused by direct runoff entering the aquifer, from the ground-water inputs to Big Spring, A significant delay between the initial increases in discharge and the arrival of direct runoff, as indicated by a steady decrease in specific conductance, represented the time required to displace this volume of phreatic water, The delay showed that sampling a karst spring only during peak discharge would be an unreliable sampling method. Runoff from two different subcatchments was tagged with tracer dye and the timing of the passage of the resultant dye clouds through Big Spring were compared to water quality variations, Distinct lag times between the arrival of direct runoff at Big Spring and the bacteria and suspended sediment waveforms were shown through the concurrent quantitative tracer tests to be related to the areal distribution of land-cover type within the basin

Influence of hydrological and climatic parameters on spatial-temporal variability of fluorescence intensity and DOC of karst percolation waters in the Santana Cave System, Southeastern Brazil, 2005, Cruz J, Karmann I, Magdaleno Gb, Coichev N, Viana J,
Fluorescence intensity (FI) and organic carbon concentration of groundwater percolating through soil and rock into the Santana Cave were monitored at eight different cave sites between 2000 and 2002 to investigate their relationships to climatic parameters, stalactite discharge and thickness of rock overlying the cave. FI values, compared among sampling sites, are inversely proportional to depth and directly proportional to discharge; in contrast, dissolved organic matter (DOC) shows no significant spatial variability. Time-series analysis demonstrated similarities in DOC trends of different waters, but no correlation was observed with FI trends. Combined evaluation of DOC of infiltration waters, rainfall data and chemical parameters of Fe, O2, pH, Eh in soil solution indicate that peaks in DOC content coincide with more reduced conditions in the soil and have a lag time of 2-3 months after heavy showers. Variation of FI throughout the year occurs at all sampling sites but only higher drip discharge and rimstone pool waters were correlatable to rainfall events. FI of lower discharge sampling sites shows similar trends, but no relationship between drip discharge and rainfall variation was observed. Ranges and means of FI for all drip waters were significantly higher in the 2001-2002 period than in the preceding 2000-2001 period, which correlates with a 5.5 [deg]C increase in mean austral winter temperatures in 2001. Hence, FI variations of karst waters that form carbonate speleothems under a humid subtropical climate may provide a useful proxy in paleoenvironmental reconstruction

Application of spectral analysis of daily water level and spring discharge hydrographs data for comparing physical characteristics of karstic aquifers, 2005, Rahnemaei M. , Zare M. , Nematollahi A. R. , Sedghi H. ,
Bivariate time series techniques (in spectral domain) of daily rainfall and water level of piezometers or discharge of springs in karstic aquifers are employed to evaluate the lag times (delay) of aquifers response to rainfall events. The evaluation results show that the physical characteristics of karstic aquifers can be compared with each other by using the outcomes of these analyses. With attention to dual porosity idea of karstic aquifers, two lag times (t(1), t(2)) can be computed, which, are related to flow of water through larger fractures (conduit flow) and matrix of the rock (diffuse flow), respectively. Results obtained from these functions, correspond to the findings of physical characteristics, compiled from field investigations. Comparable to dual porosity idea in regard to recharge through the larger fractures (in the first step) and finer porosity of the rock (in the second step), the idea of 'Dual Recharge' in karstic aquifers is presented. Application of these techniques is verified using daily rainfall and water level of Qara, Sabzpooshan and Kaftarak piezometers and daily discharge of Qasreqhomsheh karst spring in Maharlu basin in Iran (52 degrees 20 '-52 degrees 40 ' E and 29 degrees 20 '-29 degrees 40 ' N) having different degree of karstification in their surroundings. (c) 2005 Elsevier B.V. All rights reserved

Isotopic Investigations of Cave Drip Waters and Precipitation in Central and Northern Florida, USA, Msc.Thesis, 2007, Pacegraczyk, Kali J

A temperature, drip rate, and stable isotopic study (δ18O and δD) was undertaken in three caves in central and northern Florida. Both surface and cave temperatures were collected, as were precipitation, cave drip water and drip rates. All data were collected on a weekly basis to investigate the isotopic relationships between precipitation and cave drip waters. The objective of this study was to provide a calibration of the oxygen and hydrogen isotopic values in precipitation and cave drip water for future paleoclimate work in the Florida peninsula.Based on the steady annual cave temperature and high relative humidity (95% or above), all three caves are suitable locations for paleoclimate work. A spike in the cave drip rate is seen following precipitation events at both Legend and Jennings Caves. A lag time of 52 days between the date of the storm event and the increase in drip rate was found at Legend Cave.

Legend and Jennings Caves in central Florida show a relationship between the amount of precipitation and the δ18O values. The isotopic values in precipitation were more depleted after a large precipitation event, suggesting the amount effect is influential in this location. At Florida Caverns State Park tourist cave in northern Florida, the association between 18O and precipitation was weak while a relationship between 18O and temperature may be present; here the seasonal effect or latitude effect may be significant.
The monthly mean isotopic values of the drip waters were found to approximate those of the precipitation. The steady isotopic values of the drip water are due to a homogenization of water infiltrating into the epikarst and mixing with water already present in the karst storage. This finding is important for future paleoclimate research in the Florida peninsula. An important assumption in paleoclimate work is that the value of δ18O in calcite at the time of precipitation represents the mean annual δ18O of precipitation at the time of deposition. The ultimate objectives of this research were to assess the isotopic relationship between precipitation and cave drip waters in order to interpret paleoclimate data sets. Although the data were limited to a single year, it appears that a sufficient isotopic signal exists in central-north Florida precipitation and drip water to apply for paleoclimate studies.

Chemical and isotopic (d18O%, d2H%, d13C%, 222Rn%) multi-tracing for groundwater conceptual model of carbonate aquifer (Gran Sasso INFN underground laboratory central Italy), 2008, Adinolfi Falcone R. , Falgiani A. , Parisse B. , Petitta M. , Spizzico M. , Tallini M.

A hydrochemical and isotope study was conducted on the drainage waters of an underground laboratory, located inside the Gran Sasso massif (central Italy). The study was expected to improve the conceptual model of groundwater circulation at the base of an over 1000-thick unsaturated zone in the Gran Sasso partitioned karst aquifer. This lithostratigraphically and tectonically complex aquifer is typical of Africa–Europe thrust-andfold collision belt in the Mediterranean area. In this case, investigations on water–rock interactions during recharge in complex aquifers, overlaid by a thick unsaturated zone, have been made thanks to the strategic location of the Gran Sasso underground laboratories, located in the core of a huge carbonate aquifer. Knowledge of the local basic hydrogeological setting was the starting point for a detailed hydrogeochemical and isotopic study, which was carried out at the aquifer scale and at the fine scale in the underground laboratories. The water–rock interaction processes were investigated both spatially and in temporal sequences, analysing recharge waters and groundwater in the underground laboratories by multitracing techniques, including major ions and d18O&, d2H& and d13C& stable isotopes. Use of 222Rn provides information on transit time in the aquifer. Processes proved to be typical of carbonate rocks, with clear influence of vertical movement of water on chemical–physical parameters through the unsaturated zone. Conversely, in the saturated zone, these processes proved to be dominantly affected by local geological–structural conditions. A conceptual model with dual flow velocity is proposed, directly related to the local geological-structural setting. 222Rn decay enables to calculate an effective velocity of around 10 m/day for the fracture network, through the sequence of less permeable dolomites and underlying limestone. Lag time between recharge and chemical changes in the saturated zone testifies to an effective velocity of about 35 m/day for fast flow through recent and active extensional faults

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