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Enviroscan Ukrainian Institute of Speleology and Karstology

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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 ground water, unconfined is water in an aquifer that has a water table. synonymous with phreatic ground water [22].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for geophysics (Keyword) returned 41 results for the whole karstbase:
Showing 16 to 30 of 41
Deep karst conduits, flooding, and sinkholes: lessons for the aggregates industry, 2002, Lolcama J. L. , Cohen H. A. , Tonkin M. J. ,
Limestone aggregate quarries in deeply penetrating karst terrain are often at considerable risk of artesian inflow from groundwater or surface water channeled through the karstic aquifer. The inflow occurs through what are likely to be complex conduits that penetrate hundreds of feet into bedrock. Rates of inflow can exceed the operation's pumping capabilities proving to be uneconomic to manage over the long term. Over time, inflow rates can increase dramatically as turbulent flow through the conduit erodes its soft residual clay-rich fill. One recent investigation observed an inflow rate of more than 40,000 gpm from a surface water source. Floodwater persistently laden with sediment is an indicator of conduit washout and implies increasing inflow rates over time. Conduits carrying floodwater can exist in a variety of forms: along deeply penetrating geologic faults, joints, or following the path of preferentially eroded bedding. Preferential structural deformation along faults or bedding can enhance dissolution during subsequent interaction with groundwater. The resulting conduit may be a complex combination of many geological features, making the exploration and remediation of the pathway difficult. Sinkholes at the site can occur within several contexts. Pre-existing subsidence structures can reactivate and subside further, forming new collapse sinkholes within soil directly overlying the conduit. Cover-collapse sinkhole development can be a direct result of increasing downward groundwater velocities and subsurface erosion associated with the enlargement of a conduit. Normal operation events such as a quarry blast can also provide a significant new linkage between the groundwater and the quarry, allowing rapid drainage of the groundwater reservoir. With such drainage and erosion of karst-fill, sinkholes will develop over localized water table depressions, most significantly over enhanced permeability zones associated with fractures. Paradoxically, although the rise in quarry water level will lead to regional reduction in the hydraulic gradients, on local scales, drainage of the groundwater reservoir increases gradients and leads to the development of cover-collapse sinkholes. Recommended methods for preliminary site investigation can include a detailed review of geological literature and drilling logs to compile a conceptual model of the site. A fracture trace analysis with EM geophysics can confirm the locations of major faults and fractures. Fingerprinting of the various water sources to the quarry and the water in the quarry is an inexpensive and effective means of identifying the source and likely direction of the groundwater and surface water flow. Automated geophysical equipment on the market for performing rapid resistivity and microgravity surveys speeds up the site screening process during reconnaissance exploration for deep structure. It is recommended that mine planning fully incorporate this information so that quarry operators can take proactive measures to avoid catastrophic and costly flooding events. (C) 2002 Elsevier Science B.V. All rights reserved

Integrated high-resolution geophysical investigations as potential tools for water resource investigations in karst terrain, 2002, Mcgrath R. J. , Styles P. , Thomas E. , Neale S. ,
Karstic aquifers can be particularly vulnerable to both pollution from surface activities and large-scale dewatering from mineral winning operations. This is because of the enhanced vertical and lateral flow paths, resulting from the dissolution of carbonate species by rainfall. Often this process results in the development of voids that can range in size from several centimetres to several tens of metres. To date, groundwater vulnerability maps for England and Wales, including karst areas, have been produced using a methodology that does not consider the presence of karst features. The uncertainties that are presented by the potential for pollution by the presence of water-carrying conduits in karst areas, where there are proposed or existing limestone quarries, require new techniques for detecting and delineating underground cave systems. In order for any mapping technique to provide an acceptable assessment of vulnerability, the location and spatial distribution of high permeability flow paths need to be established. Of the available geophysics techniques that may allow for the identification of such features, microgravity and resistivity imaging are likely to be the most successful. Microgravity surveying has the potential to identify the presence and location of such voids, and with the integration of electrical tomographic work, can provide 'targets' for the location of monitoring boreholes. Whilst these techniques are intensive and may not be cost effective on a regional scale, they do have the potential to provide high-resolution data over smaller areas, which would be invaluable to any site or area-specific assessment of vulnerability

Detecting preferential infiltration pathways in soils using geophysics, 2002, Carpenter Pj, Ahmed S,

Geophysical evidence for karst formation associated with offshore groundwater transport: An example from North Carolina, 2003, Evans Rl,
Marine geophysical data from Long Bay, North Carolina, involving a novel combination of electromagnetic and high-resolution Chirp seismics, show evidence of submarine karst formation associated with what has been inferred to be a site of high-flux submarine groundwater discharge (SGD) a substantial distance offshore. Recently observed temperature and chemical signals from wells in this area provide the basis for the interpretation of the high-flux SGD here, and they also suggest a terrestrial source for the groundwater and thus a potentially important route for nutrient transport to the oceans. Our data indicate that karstification is localized to the high-flux zone, and we suggest that mixing of the chemically distinct (but saline) groundwater with seawater has resulted in the karstification. As karstification increases permeability and flux, a positive feedback would tend to progressively enhance submarine groundwater discharge. Our data reveal a significant local anomaly in apparent porosity: a dense block that may have initiated the local focusing of groundwater flow. Conditions favorable to the formation of similar locally punctuated sites of high-flux SGD are likely to exist along the mid to inner shelf of the southeastern United States, where carbonate aquifers are prevalent

Localization of saturated karst aquifer with magnetic resonance sounding and resistivity imagery, 2003, Vouillamoz J. M. , Legchenko A. , Albouy Y. , Bakalowicz M. , Baltassat J. M. , Alfares W. ,
To answer one of the main questions of hydrogeologists implementing boreholes or working on pollution questions in a karst environment-i.e., where is the ground water?-numerous tools including geophysics are used. However, the contribution of geophysics differs from one method to the other. The magnetic resonance sounding (MRS) method has the advantage of direct detection of ground water over other geophysical methods. Eight MRSs were implemented over a known karst conduit explored and mapped by speleologists to estimate the MRS ability to localize ground water. Two direct current resistivity imageries (DC-2D imagery) were also implemented to check their capability to map a known cave. We found that the MRS is a useful tool to locate ground water in karst as soon as the quantity of water is enough to be detected. The threshold quantity is a function of depth and it was estimated by forward modeling to propose a support graph to hydrogeologists. The measured MRS's signals could be used to calculate transmissivity and permeability estimators. These estimators were used to map and to draw a cross section of the case study site, which underline accurately the known karst conduit location and depth. We also found that the DC-2D imagery could underline the karst structures: It was able to detect the known cave through its associated faults. We prepared a computer simulation to check the depth of such a cave to induce resistivity anomaly which could be measured in similar conditions

Inversion strategy in crosshole radar tomography using information of data subsets, 2004, Becht A, Tronicke J, Appel E, Dietrich P,
Detecting discrete anomalies, such as cavities or tunnels, is an important application of crosshole radar tomography. However, crosshole tomographic inversion results are frequently ambiguous, showing smearing effects and inversion artifacts. These ambiguities lead to uncertainties in interpretation; hence, the size and position of anomalies can only be interpreted with limited accuracy and reliability. We present an inversion strategy for investigating discrete anomalies with crosshole radar tomography. In addition to the full traveltime data set, we use subsets of specified ray-angle intervals for tomographic inversion. By analyzing inversion results from different ray-angle intervals, a more accurate interpretation of anomalies is possible. The second step of our strategy is to develop a good inhomogeneous starting model from joint interpretation of the inversion results from different subsets. The third step is to invert the full data set using this new starting model and to evaluate the inversion results by analyzing the distributions of mean square traveltime residuals with respect to the ray angles. We use a synthetic model with two discrete anomalies located roughly at the same depth to demonstrate and evaluate our approach. This inversion strategy is also applied to a field data set collected to investigate karst cavities in limestone. From the inversion results of both examples, we show that horizontal smearing of anomalies can be reduced by eliminating near-horizontal rays. A good starting model can be obtained based on the joint interpretation of the inversion results of the different subsets; it leads to a high-resolution final image of the full data set

Investigation of Karst Cavities and Earth Subsidence with Combined Application of Boring and Geophysics in the Progress of High-Speed Railway Routes, 2004, Lehmann Bodo, Ttler Rudolf, Radinger Alexander, K_ Hne,

Improved karst exploration by VLF-EM-gradient survey: comparison with other geophysical methods, 2005, Bosch Fp, Muller I,
The knowledge of size, density and both orientation and vertical distribution of fractures as well as their opening and filling material or overburden thickness is a valuable contribution to estimating hydraulic conductivity and to evaluating the vulnerability and protection strategy of karst aquifers. To obtain some of these parameters and to ascertain high-permeability zones, the Very Low Frequency-Electromagnetic Gradient (VLF-EM GRAD) method was applied, together with Radio Frequency-Electromagnetics (RF-EM), Radioinagnetotellurics (RMT), Geoelectrical Tomography and refraction seismics, over a karstic terrain in the Swiss Jura Mountains. In this area, karst springs infiltrate a porous aquifer. This survey investigated the highly permeable karst structures, which provide fast water-infiltration pathways into the karstic flow network. A dye tracer test validated the geophysical results. The results show the efficiency and reliability particularly of the VLF-EM GRAD method, for high-resolution investigation at shallow depths and for its potential for fast data acquisition over large surfaces at catchment area scale without ground contact

The search for Palmer's Chamber, Lamb Leer, Somerset, United Kingdom, 2006, Butcher, Antony, Phillip J Murphy, Simon Beaney And Roger Clark.
During the late 1930s and 1950s a series of geophysical resistivity measurements were acquired by Professor Leo Palmer of Hull University over the Lamb Leer cave system (referred to as Lamb Lair by Palmer), which is located within the Mendip Hills, Somerset. Through his surveys, Professor Palmer reportedly delineated a resistive zone that he believed to correspond to the location of the Great Chamber of Lamb Leer, a 30m-diameter cavity located at 35m below ground level. Additionally, he concluded that a further large cavern of similar size existed some 100m northeast of the Great Chamber. In an attempt to confirm the existence and establish the nature of "Palmer's Chamber", a series of resistivity and microgravity profiles were carried out during the summers of 2004 and 2006. The resistivity survey confirmed the presence of a resistive anomaly within the vicinity of "Palmer's Chamber"; however the resulting microgravity data do not suggest the presence of a mass deficiency feature that would be expected over a significant void.

Evidence for hydraulic heterogeneity and anisotropy in the mostly carbonate Prairie du Chien Group, southeastern Minnesota, USA, 2006, Tipping Robert G. , Runkel Anthony C. , Alexander Jr. E. Calvin, Alexander Scott C. , Green Jeffery A. ,
In southeastern Minnesota, Paleozoic bedrock aquifers have typically been represented in groundwater flow simulations as isotropic, porous media. To obtain a more accurate hydrogeologic characterization of the Ordovician Prairie du Chien Group, a new approach was tested, combining detailed geologic observations, particularly of secondary porosity, with hydraulic data. Lithologic observations of the depositional and erosional history of the carbonate-dominated bedrock unit constrained characterization of both primary (matrix) and secondary porosity from outcrops and core. Hydrostratigraphic data include outcrop and core observations along with core plug permeability tests. Hydrogeologic data include discrete interval aquifer tests, borehole geophysics, water chemistry and isotope data, and dye trace studies. Results indicate that the Prairie du Chien Group can be subdivided into the Shakopee aquifer at the top, consisting of interbedded dolostone, sandstone and shale, and the underlying Oneota confining unit consisting of thickly bedded dolostone. The boundary between these two hydrogeologic units does not correspond to lithostratigraphic boundaries, as commonly presumed. Groundwater flow in the Shakopee aquifer is primarily through secondary porosity features, most commonly solution-enlarged bedding planes and sub-horizontal and vertical fractures. Regional scale preferential development of cavernous porosity and permeability along specific stratigraphic intervals that correspond to paleokarst were also identified, along with a general depiction of the distribution of vertical and horizontal fractures. The combination of outcrop and core investigations, along with borehole geophysics, discrete interval aquifer tests, water chemistry and isotope data and dye trace studies show that the Prairie du Chien Group is best represented hydrogeologically as heterogeneous and anisotropic. Furthermore, heterogeneity and anisotropy within the Prairie du Chien Group is mappable at a regional scale (> 15,000 km2)

Application of carbonate cyclostratigraphy and borehole geophysics to delineate porosity and preferential flow in the karst limestone of the Biscayne Aquifer, SE Florida, 2006, Cunningham K. J. , Renken R. A. , Wacker M. A. , Zygnerski M. R. , Robinson E. , Shapiro A. M. , Wingard G. L.

Methods in Karst Hydrogeology, 2007,
The importance of investigating karstified aquifers lies in their significance as a major source of drinking water. This book describes methods that are basic to all hydrogeological studies, such as hydraulic investigations, hydrochemistry, geophysics, isotope chemistry and modelling, but with the emphasis placed on their application to karst systems. Other techniques are specific to the karst environment, such as the speleological exploration of aquifers and water tracing. The various chapters of this book are written by experts in different methods. Most of the chapters are multi-authored, and the authors include hydrogeologists who are experienced in evaluating a variety of karst environments and who together, provide a comprehensive review of karst methods.

GEOMETRY AND DRAINAGE OF A RETREATING GLACIER OVERLYING AND RECHARGING A KARST AQUIFER, TSANFLEURON-SANETSCH, SWISS ALPS, 2010, Gremaud V. , Goldscheider N.
Alpine glaciers store large amounts of freshwater contributing to groundwater recharge during warmer periods, but the interactions between glaciers and aquifers have rarely been investigated in detail. The Tsanfleuron-Sanetsch area, Switzerland, is an ideal test site to study glacier-aquifer interactions. It consists of a rapidly retreating glacier (2.8 km2) overlying a karst aquifer drained by a spring (mean discharge 600700 L/s) used for drinking water supply and irrigation. The geometry and structure of the glacier were assessed by means of geophysical surveys, using radiomagnetotellurics (RMT). The estimated ice volume is 1.0 x 10^8 m3 (0.92 x 10^8 m3 water equivalent), but the glacier currently loses 1.5 m ice thickness per year. Field observations, flow measurements and tracer tests allowed characterisation of glacier drainage and aquifer recharge. Three recharge pathways have been identified: 1) The main glacial stream sinks into the aquifer via swallow holes 3 km downstream of the glacier mouth; 2) Numerous small meltwater streams sink underground shortly below the glacier front; 3) Subglacial meltwaters and supraglacial streams sink into the glacier via moulins and contribute to aquifer recharge through fractures and swallow holes underneath the glacier. Recharge and spring discharge display strong diurnal and seasonal variability, with a general highflow period during snow and glacier melt from spring to autumn. Preliminary predictions of the future availability of spring water after disappearance of the glacier suggest that the discharge may decrease by 2030%. Nearly all of this loss will occur in summer and autumn, presumably resulting in temporary water shortage.

THE USE OF MULTIPLE TECHNIQUES FOR CONCEPTUALISATION OF LOWLAND KARST, A CASE STUDY FROM COUNTY ROSCOMMON, IRELAND, 2010, Hickey C.
This paper summarises research carried out in county Roscommon, Ireland to characterise the workings of low-lying karst, of which little is known. The research employed a combination of five main investigative techniques, in conjunction: geomorphological mapping, spring chemistry and discharge analyses, dye-tracing, microgravity geophysical investigations and bedrock core drilling. The results enabled the production of a detailed conceptual model for the area. Surface and subsurface karst landform mapping revealed a high level of karstification. Clustering and alignment of recharge landforms is found to be a significant aspect of the karst. Analyses of spring chemistry and discharge data revealed characteristics of the aquifer systems in operation. It was found that a significant percentage of flow is via enlarged conduits but that the smaller fractures are important for providing base flow. Water tracing experiments proved that water moved from highly karstified, elevated recharge zones to springs at the periphery. Microgravity geophysical investigations, detected and located solutionally enlarged voids in the bedrock and demonstrated the importance of the shallow epikarst system as well as a deeper conduit network. Bedrock core drilling detailed the nature of the bedrock underneath karst landforms and showed the successes and failings of the geophysical investigations. Spring catchment boundaries were then delineated using water balance equations and a combination of the information retrieved from the other methods. Using these results in combination large amounts of information were gathered leading to the production of the first conceptual model for the karst of Roscommon, which can be adapted and applied to Irish Lowlands in general. The use of multiple, complimentary, investigative techniques in conjunction greatly enhanced the accuracy and success of this project. The aim of this paper, therefore is to highlight the benefits of using many analytical techniques together.

Deep confined karst detection, analysis and paleohydrology reconstruction at a basin-wide scale using new geophysical interpretation of borehole logs, 2011, Laskow M. , Gendler M. , Goldberg I. , Gvirtzman H. , Frumkin A.

Deep karst voids can be identified by a new geophysical interpretation method of commonly used borehole logs at deeply confined carbonate aquifers. We show that deep, buried karst voids can be characterized by combining this geophysical interpretation together with geological and hydrological data, and known speleological constraints. We demonstrate how this characterization can reveal past hydrological regimes and allow mapping of karst distribution on a basin-wide scale.

A combined analysis of geophysical, geological, hydrological and speleological data in the confined Yarkon-Taninim aquifer, Israel, led us to reconstruct past groundwater levels at different sea levels and reliefs, with the karst voids as a marker for long-term flow close to the water table. Paleo-canyons along the Mediterranean Sea shoreline strongly affected the region’s paleohydrology, by serving as major outlets of the aquifer during most of the Cenozoic. We conclude that intensive karstification was promoted by flow periods of longer duration and/or higher flux and flow velocities close to the aquifer’s past and present outlets. In addition, we suggest that karst voids found under shallow confinement was developed by renewed aggressivity achieved by hypogene water rising in cross-formational flow, mixed with fresh lateral water flow from the east.


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