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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 nival karst is alpine karst [1].?

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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 aquifer systems (Keyword) returned 37 results for the whole karstbase:
Showing 16 to 30 of 37
Tracer-test design for losing streamaquifer systems., 2006, Field M. F.

On the importance of geological heterogeneity for flow simulation, 2006, Eaton Tt,
Geological heterogeneity is recognized as a major control on reservoir production and constraint on many aspects of quantitative hydrogeology. Hydrogeologists and reservoir geologists need to characterize groundwater flow through many different types of geological media for different purposes. In this introductory paper, an updated perspective is provided on the current status of the long effort to understand the effect of geological heterogeneity on flow using numerical simulations. A summary is given of continuum vs. discrete paradigms, and zonal vs. geostatistical approaches, all of which are used to structure model domains. Using these methods and modern simulation tools, flow modelers now have greater opportunities to account for the increasingly detailed understanding of heterogeneous aquifer and reservoir systems.One way of doing this would be to apply a broader interpretation of the idea of hydrofacies, long used by hydrogeologists. Simulating flow through heterogeneous geologic media requires that numerical models capture important aspects of the structure of the flow domain. Hydrofacies are reinterpreted here as scale-dependent hydrogeologic units with a particular representative elementary volume (REV) or structure of a specific size and shape. As such, they can be delineated in indurated sedimentary or even fractured aquifer systems, independently of lithofacies, as well as in the unlithified settings in which they have traditionally been used. This reconsideration of what constitutes hydrofacies, the building blocks for representing geological heterogeneity in flow models, may be of some use in the types of settings described in this special issue

Observations on the biodiversity of sulfidic karst habitats, 2007, Engel Annette Summers
Recognition of the metabolic process of chemosynthesis has recently overthrown the ecological dogma that all life on earth is dependent on sunlight. In complete darkness, complex ecosystems can be sustained by the energy and nutrients provided by chemosynthetic microorganisms. Many of these chemosynthetically-based ecosystems result from microbial manipulation of energy-rich sulfur compounds that can be found in high concentrations in groundwater. Subsurface environments in general can be highly stressful habitats (i.e., darkness, limited food, etc.), but in the case of sulfidic groundwater habitats, organisms must also tolerate and adapt to different stresses (e.g., toxic levels of gases or lethally low oxygen concentrations). Nevertheless, these habitats, and specifically cave and karst aquifers, have a richly diverse fauna. This review focuses on the biodiversity (as the number and types of species) of sulfur-based cave and karst aquifer systems. The relationships among ecosystem productivity, biodiversity, and habitat and ecosystem stresses are explored. The relatively high numbers of species and complex trophic levels could be attributed to the rich and plentiful, chemosyntheticallyproduced food source that has permitted organisms to survive in and to adapt to harsh habitat conditions. The geologic age and the hydrological and geochemical stability of the cave and karst aquifer systems may have also influenced the types of ecosystems observed. However, similar to non-sulfidic karst systems, more descriptions of the functional roles of karst aquifer microbes and macroscopic organisms are needed. As subterranean ecosystems are becoming increasingly more impacted by environmental and anthropogenic pressures, this review and the questions raised within it will lead to an improved understanding of the vulnerability, management, and sustainability challenges facing these unique ecosystems.

Evaluating the impact of quarrying on karst aquifers of Salento (southern Italy), 2007, Le Rose M. , Parise M. , Andriani G. F. ,
This paper describes a case study in the Salento karst (Apulia, southern Italy) in a site that has been intensively used to quarry limestones in the last 30 years. After quarrying activity had stopped, the site was transformed into legal and illegal landfills where solid and liquid wastes have been repeatedly dumped, with serious consequences for the groundwater resources. In this paper, through a geological, petrographical and hydrogeological approach, we attempt to assess the consequences of the anthropogenic activities on the local hydrogeology, with particular regard to the surficial aquifer that is contained in the Plio-Quaternary calcarenites cropping out in the area. Application of some well-known methods to assess the vulnerability of aquifer systems to contamination by human activities (DRASTIC, SINTACS, LeGrand and GOD) highlights the limits of such an approach in karst environment, and the necessity to include in the methods data strictly related to the peculiarity of karst. This is further evidenced by application of the EPIK method, specifically designed for karst areas. The final part of the paper focuses on the need of a thorough understanding of the hydrogeological setting for a better management and policy action of karst environments

PROPOSED METHODOLOGY OF VULNERABILITY AND CONTAMINATION RISK MAPPING FOR THE PROTECTION OF KARST AQUIFERS IN SLOVENIA, 2007, Ravbar N. , Goldscheider N.

On the basis of work accomplished by the European COST Action 620, a comprehensive approach to groundwater vulnerability and contamination risk assessment is proposed, taking into account the special characteristics of Slovene karst aquifer systems. The Slovene Approach is consistent with national environmental legislation and enables comparison across European countries. The method integrates temporal hydrological variability in the concept of groundwater vulnerability and offers a new possibility to combine surface and groundwater source and resource protection, which required the development of a new K factor (karst groundwater flow within the saturated zone). The risk analysis considers intrinsic vulnerability, contamination hazards and the importance of the source or resource. It has been first applied to the Podstenjšek springs catchment in southwestern Slovenia and validated by means of two multi-tracer tests with a total of six injection points. The resulting vulnerability, hazard and risk maps are plausible, and the validation confirmed the vulnerability assessment at the representative sites that were selected for tracer injection. The maps provide improved source protection zones and make it possible to identify land mismanagement and to propose better practices for future planning.


Tracer tests in karst hydrogeology and speleology, 2008, Goldscheider N. , Meiman J. , Pronk M And Smart C.
This article presents an introduction to the fundamentals of tracing techniques and their application in cave and karst environments, illustrated by case studies from the Mammoth Cave, USA, and a small experimental site in Switzerland. The properties and limitations of the most important artificial tracers are discussed, and the available methods of tracer injection, sampling, online monitoring and laboratory analysis are presented. Fully quantitative tracer experiments result in continuous or discrete concentration-time data series, i.e. breakthrough curves, and concomitant discharge data, which make it possible to obtain detailed information about groundwater flow and contaminant transport. Within the frame of speleological investigations, tracer tests can help to resolve the active and often inaccessible part of cave and conduit networks and to obtain indications about the geometry and volume of the conduits. For hydrogeological studies, caves can in turn be used as natural experimental and monitoring sites inside the unsaturated or saturated zone of karst aquifer systems.

Tracer tests in karst hydrogeology and speleology, 2008, Goldscheider N. , Meiman J. , Pronk M. , Smart C.

This article presents an introduction to the fundamentals of tracing techniques and their application in cave and karst environments, illustrated by case studies from the Mammoth Cave, USA, and a small experimental site in Switzerland. The properties and limitations of the most important artificial tracers are discussed, and the available methods of tracer injection, sampling, online monitoring and laboratory analysis are presented. Fully quantitative tracer experiments result in continuous or discrete concentration-time data series, i.e. breakthrough curves, and concomitant discharge data, which make it possible to obtain detailed information about groundwater flow and contaminant transport. Within the frame of speleological investigations, tracer tests can help to resolve the active and often inaccessible part of cave and conduit networks and to obtain indications about the geometry and volume of the conduits. For hydrogeological studies, caves can in turn be used as natural experimental and monitoring sites inside the unsaturated or saturated zone of karst aquifer systems.


Characterization of Spatial Heterogeneity in Groundwater Applications , 2009, Trinchero, Paolo

Heterogeneity is a salient feature of every natural geological formation. In the past decades a large body of literature has focused on the effects of heterogeneity on flow and transport problems. These works have substantially improved the understanding of flow and transport phenomena but still fail to characterize many of the important features of an aquifer. Among them, preferential flows and solute paths, connectivity between two points of an aquifer, and interpretation of hydraulic and tracer tests in heterogeneous media are crucial points that need to be properly assessed to obtain accurate model predictions. In this context, the aim of this thesis is twofold:

· to improve the understanding of the effects of heterogeneity on flow and transport phenomena
· to provide new tools for characterizing aquifer heterogeneity

First, we start by theoretically and numerically examine the relationship between two indicators of flow and transport connectivity. The flow connectivity indicator used here is based on the time elapsed for hydraulic response in a pumping test (e.g., the storage coefficient estimated by the Cooper-Jacob method, Sest). Regarding transport, we select the estimated porosity from the observed breakthrough curve (Φ est) in a forced-gradient tracer test. Our results allow explaining the poor correlation between these two indicators, already observed numerically by Knudby and Carrera (2005).

Second, a geostatistical framework has been developed to delineate connectivity patterns using a limited and sparse number of measurements. The methodology allows conditioning the results to three types of data measured over different scales, namely: (a) travel times of convergent tracer tests, ta, (b) estimates of the storage coefficient from pumping tests interpreted using the Cooper-a Jacob method, S est, and (c) measurements of transmissivity point values, T. The ability of the methodology to properly delineate capture zones is assessed through estimations (i.e. ordinary cokriging) and sequential gaussian simulations based on different sets of measurements.


Third, a novel methodology for the interpretation of pumping tests in leaky aquifer systems, referred to as the double inflection point (DIP) method, is presented. The real advantage of the DIP method comes when it is applied with all the existing methods independently to a test in a heterogeneous aquifer. In this case each method yields parameter values that are weighted differently, and thus each method provides different information about the heterogeneity distribution. In particular, the combination of the DIP method and Hantush method is shown to lead to the identification of contrasts between the local transmissivity in the vicinity of the well and the equivalent transmissivity of the perturbed aquifer volume.

Fourth, the meaning of the hydraulic parameters estimated from pumping test performed in leaky aquifers is assessed numerically within a Monte Carlo framework. A synthetic pumping test is interpreted using three existing methods. The resulting estimated parameters are shown to be space dependent and vary with the interpretation method, since each method gives different emphasis to different parts of the timedrawdown data. Finally, we show that by combining the parameter estimates obtained from the different analysis procedures, information about the heterogeneity of the leaky aquifer system may be inferred.
Fifth, an unsaturated highly heterogeneous waste rock pile is modeled using a simple linear transfer function (TF) model. The calibration of the parametric model provides information on the characteristic time of the flow through the matrix and on the fraction of the water that, within each section, is channeled through the macropores. An analysis of the influence of the scale on the results is also provided showing that at large scales the behavior of the system tends to that of an equivalent matrix reservoir masking the effects of preferential flow.


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.

Groundwater fluctuations in heterogeneous coastal leaky aquifer systems , 2010, Chuang M. H. , Huang C. S. , Li G. H. , Yeh H. D.

In the past, the coastal leaky aquifer system, including two aquifers and an aquitard between them, was commonly assumed to be homogeneous and of infinite extent in the horizontal direction. The leaky aquifer system may however be heterogeneous and of finite extent due to variations in depositional and post depositional processes. In this paper, the leaky aquifer system is divided into several horizontal regions for the heterogeneous aquitard and underlying aquifer. A one-dimensional analytical model is developed for describing the head fluctuation in such a heterogeneous leaky aquifer system. The hydraulic head of the upper unconfined aquifer is assumed constant. It is found that both the length and location of the discontinuous aquitards presented in the coastal area have significant effects on the amplitude and phase shift of the head fluctuation in the lower aquifer. In addition, the influence of the formation heterogeneity on the spatial head distribution is also investigated.


Groundwater fluctuations in heterogeneous coastal leaky aquifer systems, 2010, Chuang M. H. , Huang C. S. , Li G. H. , Yeh H. D.

In the past, the coastal leaky aquifer system, including two aquifers and an aquitard between them, was commonly assumed to be homogeneous and of infinite extent in the horizontal direction. The leaky aquifer system may however be heterogeneous and of finite extent due to variations in depositional and post depositional processes. In this paper, the leaky aquifer system is divided into several horizontal regions for the heterogeneous aquitard and underlying aquifer. A one-dimensional analytical model is developed for describing the head fluctuation in such a heterogeneous leaky aquifer system. The hydraulic head of the upper unconfined aquifer is assumed constant. It is found that both the length and location of the discontinuous aquitards presented in the coastal area have significant effects on the amplitude and phase shift of the head fluctuation in the lower aquifer. In addition, the influence of the formation heterogeneity on the spatial head distribution is also investigated.


Karstification beneath dam-sites: From conceptual models to realistic scenarios, 2011, Hiller Thomas, Kaufmann Georg, Romanov Douchko

Dam-sites and reservoirs located above soluble rock are often damaged by increased leakage through the sub-surface within the life-time of the structure. The high hydraulic gradients driving the water through the fracture and fissure system of the bedrock have a strong impact on the aquifer evolution. The increased permeability, if not prevented, leads to an imminent danger of high leakage rates (breakthrough) as well. As a result, the structural safety of the dam-site itself is at risk. Past experience has shown that this may have large environmental and economical consequences.

For a better understanding of the evolution of karst aquifer systems in the vicinity of dam-sites, a three-dimensional conceptual model is presented. We show the evolution of the karst aquifer for simple three-dimensional dam-site setups. Keeping the symmetry and simplicity of the models we can relate our results to the two- and one-dimensional scenarios presented in the past. Implementing a statistical fracture network and topographic information to this basic setup we show that these complex three-dimensional properties of the real aquifers, have a significant influence on the karstification, and cannot always be addressed by two -and one-dimensional models.

Research highlights
- Three-dimensional karst evolution modeling of dam-sites. - Relating the 3D models to former 2D and 1D models. - Implementation of statistical fracture network and topography.


Review: The Yucatan Peninsula karst aquifer, Mexico , 2011, Bauergottwein Peter, Gondwe Bibi R. N. , Charvet Guillaume, Marin Luis E. , Rebolledovieyra Mario, Meredizalonso Gonzalo

The Yucatan Peninsula karst aquifer is one of the most extensive and spectacular karst aquifer systems on the planet. This transboundary aquifer system extends over an area of approximately 165,000 km2 in Mexico, Guatemala and Belize. The Triassic to Holocene Yucatan limestone platform is located in the vicinity of the North American/Caribbean plate boundary and has been reshaped by a series of tectonic events over its long geologic history. At the end of the Cretaceous period, the Yucatan Peninsula was hit by a large asteroid, which formed the Chicxulub impact crater. The Yucatan Peninsula karst aquifer hosts large amounts of groundwater resources which maintain highly diverse groundwater-dependent ecosystems. Large parts of the aquifer are affected by seawater intrusion. Anthropogenic pollution of the aquifer has been increasing over the past few decades, owing to relentless economic development and population growth on the Peninsula. This review summarizes the state of knowledge on the Yucatan Peninsula karst aquifer and outlines the main challenges for hydrologic research and practical groundwater-resources management on the Peninsula.


Review: The Yucatn Peninsula karst aquifer, Mexico, 2011, Bauergottwein P. , Gondwe B. R. N. , Charvet G. , Marn L. E. , Rebolledovieyra M. , Meredizalonso G.

The Yucatán Peninsula karst aquifer is one of the most extensive and spectacular karst aquifer systems on the planet. This transboundary aquifer system extends over an area of approximately 165,000 km2 in México, Guatemala and Belize. The Triassic to Holocene Yucatán limestone platform is located in the vicinity of the North American/Caribbean plate boundary and has been reshaped by a series of tectonic events over its long geologic history. At the end of the Cretaceous period, the Yucatán Peninsula was hit by a large asteroid, which formed the Chicxulub impact crater. The Yucatán Peninsula karst aquifer hosts large amounts of groundwater resources which maintain highly diverse groundwater-dependent ecosystems. Large parts of the aquifer are affected by seawater intrusion. Anthropogenic pollution of the aquifer has been increasing over the past few decades, owing to relentless economic development and population growth on the Peninsula. This review summarizes the state of knowledge on the Yucatán Peninsula karst aquifer and outlines the main challenges for hydrologic research and practical groundwater-resources management on the Peninsula


U.S. Geological Survey Karst Interest Group Proceedings, Fayetteville, Arkansas, April 2629, 2011/ Scientific Investigations Report 20115031, 2011, Av

Karst aquifer systems are present throughout parts of the United States and some of its territories and are developed in carbonate rocks (primarily limestone and dolomite) that span the entire geologic time frame. The depositional environments, diagenetic processes, and post-depositional tectonic events that form carbonate rock aquifers are varied and complex, involving both biological and physical processes that can influence the development of permeability. These factors, combined with the diverse climatic regimes under which karst development in these rocks has taken place result in the unique dual or triple porosity nature of karst aquifers. These complex hydrologic systems often present challenges to scientists attempting to study groundwater flow and contaminant transport.
The concept for developing a Karst Interest Group evolved from the November 1999 National Groundwater Meeting of the U.S. Geological Survey (USGS), Water Resources Division. As a result, the Karst Interest Group was formed in 2000. The Karst Interest Group is a loose-knit grass-roots organization of USGS employees devoted to fostering better communication among scientists working on, or interested in, karst hydrology studies.
The mission of the Karst Interest Group is to encourage and support interdisciplinary collaboration and technology transfer among USGS scientists working in karst areas. Additionally, the Karst Interest Group encourages cooperative studies between the different disciplines of the USGS and other Federal agencies, and university researchers or research institutes.
This fifth workshop is a joint workshop of the USGS Karst Interest Group and University of Arkansas HydroDays workshop, sponsored by the USGS, the Department of Geosciences at the University of Arkansas in Fayetteville. Additional sponsors are: the National Cave and Karst Research Institute, the Edwards Aquifer Authority, San Antonio, Texas, and Beaver Water District, northwest Arkansas. The majority of funding for the proceedings preparation and workshop was provided by the USGS Groundwater Resources Program, National Cooperative Mapping Program, and the Regional Executives of the Northeast, Southeast, Midwest, South Central and Rocky Mountain Areas. The University of Arkansas provided the rooms and facilities for the technical and poster presentations of the workshop, vans for the field trips, and sponsored the HydroDays banquet at the Savoy Experimental Watershed on Wednesday after the technical sessions.


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