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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 internal drainage is drainage in a closed basin and not reaching the sea [16]. it is common in maturely karsted terranes where surface water bodies are relatively nonexistent.?

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Karst environment, Culver D.C.
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Your search for conceptual models (Keyword) returned 33 results for the whole karstbase:
Showing 1 to 15 of 33
Conceptual models for carbonate aquifers, 1967, White W. B.

Conceptual models for carbonate aquifers: revisited, 1977, White W. B.

Cavern Development in the Dimensions of Length and Breadth. PhD Thesis, 1982, Ewers, Ralph Owen

Three conceptual models are proposed for the integration of the large systems of conduits responsible for groundwater flow in soluble rocks. These models are supported by laboratory experiments with scaled solution models, flow-field analogues, and evidence from existing caves.
The three models reflect different boundary conditions imposed by geologic structure and stratigraphy. They have three characteristics in common. First, the smaller elements of the larger systems propagate separately from points of groundwater input toward points of discharge as distributary networks. Second, the integration of the smaller networks proceeds headward from the resurgence, in a stepwise fashion. Third, the result of the integration process in each case is a tributary system with many inputs discharging through a single discharge point.
The potential for growth of each of the smaller networks, within a common pressure field, is related to its distance from the discharge boundary and the distribution of other inputs. The first input to establish a low-resistance link to the discharge boundary will effect a localized depression within the potential field, thus attracting the flow and redirecting the growth of nearby networks until they eventually link with it. As additional orders of links develop, the system takes on a tributary pattern.
The first model applies to steeply dipping rocks. Inputs occur where bedding planes are truncated by erosion, and discharge takes place to the strike. Conduits in this case evolve as a roughly rectangular grid of strike and dip oriented elements. Dip elements are the initial form, with subsequent integration along the strike. The type example is the Holloch in Switzerland.
The second model applies to flat-lying rocks. Inputs occur over a broad area, and discharge takes place along a linear boundary. Conduits in this case evolve in a trellised array with elements normal to the discharge boundary predating those parallel to it. These latter conduits integrate the flow. The type example is the Mammoth Cave Region, Kentucky.
The third model applies to simple systems which occur beneath an impermeable cap rock. Inputs occur where erosion has breached the capping beds. The type example is Cave Creek, Kentucky.


The role of the subcutaneous zone in karst hydrology, 1983, Williams Paul W. ,
The subcutaneous zone is the upper weathered layer of rock beneath the soil, but above the permanently saturated (phreatic) zone. It is of particular hydrological importance in karst because of its high secondary permeability, arising from the considerable chemical solution in this zone. However, corrosional enlargement of fissures diminishes with depth; thus permeability decreases in the same direction with the result that percolation is inhibited, except down widened master joints and faults. Storage of water consequently occurs in this zone, particularly after storms. The upper surface of this suspended saturated layer in the subcutaneous zone is defined by a perched water table, which slopes towards points of rapid vertical percolation. The potential induces lateral water movement converging on the most permeable areas such as beneath dolines. Leakage from the subcutaneous store sustains slow percolation in the vadose zone. Cross-correlation of rainfall with percolation rates in caves in New Mexico, U.S.A., and New Zealand reveal response lags of 2-14 weeks with no apparent relationship to depth below the surface. Other percolation sites show no correlation with rainfall; interpreted as being a consequence of considerable friction in tight fissure networks. The recognition of storage and rapid as well as very slow percolation from the subcutaneous zone requires re-interpretation of the components of hydrographs from karst springs and of some conceptual models of karst aquifers. The importance of subcutaneous storage in sustaining baseflow discharge at some sites must be recognised, as must the contribution of subcutaneous water to flood hydrographs. Methods of estimating the volumes of subcutaneous and phreatic components of karst-spring flood hydrographs are presented. The paper concludes with a discussion of the significance of subcutaneous hydrologic processes for an understanding of karst geomorphology. The desirability of explaining karst landform evolution in terms of hydrologic processes is stressed

Evolution and dynamics of soil-geomorphic systems in karst landscapes of the European north, 1997, Goryachkin S. V. , Shavrina E. V. ,
Six types of soil-geomorphic systems within sulfate-karst landscapes in the north of European Russia have been investigated. The distinctions in structure and composition of these systems are conditioned by the tectonic fault pattern and jointing of the karstland. The soil data obtained allow us to gain an insight into the essence of geomorphic processes and to evaluate the dynamics of land surface in karst landscapes. Conceptual models of the origin and dynamics of soil-geomorphic systems of karst landscapes and the model of their evolution within the zone of dense jointing of gypsum rocks under the impact of denudation processes are suggested. The assessment of geomorphic functions of the soils in karst area attests to their importance as the controls of potential erosion. Only soil-biotic processes (Litter accumulation) are undoubtedly protective, while other processes may either hinder or strongly intensify the erosion. After the Quaternary sediments are removed and the erosion starts to penetrate into the hard gypsum layer, a strong positive feedback between soil-forming and karst-forming processes appears. Thus, the final stages of the evolution of soil-geomorphic systems in karst landscapes are characterized by great dynamism

Role of cave information in environmental site characterization,, 1999, Jancin M.
For consultants concerned with developing site-specific conceptual models for flow and transport in karst, cave information can be worth accessingAt the scale of the basin, caves often display patterns that correlate with both the flow and recharge characteristics of their aquifersCharacterization of overall basin hydrology bolsters predictions and monitoring recommendations which address the siteAlthough the presence of caves beneath or near sites is rare, site-based information such as water-table maps (under both natural and pumping conditions), well water-level fluctuations, well turbidity observations, borehole-void yields during drilling, and dye-trace results, are potentially useful in defining conduit-flow boundaries to diffuse-flow blocksThe appropriate choice of dye-tracer methods should acknowledge whether most site conduits (or borehole voids, or even caves) are within the epikarst, the vadose zone, the phreatic zone, or the oscillation zoneFor inferences on site flow directions, it is useful to compare the directional frequencies of cave passages and joints, faults, and photolinears in the areaThere is evidence that where caves are well developed, there tends to be a low correlation between photolinear locations and relatively high well yieldsLNAPL migration will be retarded where main conduits are well beneath the water table, but an extensive overlying system of saturated epikarstic pores serve as trapsKarst with high seasonal or storm variations in water level will tend to repeatedly remobilize LNAPLsGiven sufficient volume, DNAPLs can penetrate vertically integrated networks of pores, fractures, or solution conduits to great depthHowever, where such pathway networks are lie above relatively tight lithologies at shallow depth, and are not sediment filled, lateral movement can greatly exceed vertical movementCharacterization of the 3-D nature of pores and pathways is an important element in understanding the migration of free product, and therefore in understanding the evolution of associated aqueous plumes

The surface-subsurface interface and the influence of geologic structure in karst, 1999, Kastning E. H.
Early studies on the development of karst focused principally on surface features (Sweeting, 1973) and dissolutional enlargement in relation to positions of the water table, influence of the lithologic and stratigraphic character of the bedrock, and geologic structureIn recent decades such studies have broadened to include the hydrodynamics of fluid flow through conduits and the geochemical kinetics of dissolution and mass transportThe history of physical speleology has been well documented by several authors (Davies, 1966; Kastning, 1981; LaMoreaux, 1994; LeGrand and Stringfield, 1973; Moore, 1960; Powell, 1975; Shaw, 1992; Sweeting, 1981; White, 1987)Emerging conceptual models of cavern development and subsurficial karst processes, in general, have evolved to include not only the characteristics of groundwater flow within the bedrock, but also the relationship of these systems to inputs and outputs at the surface (zones of recharge and discharge respectively)The general premises of conceptual models of cave and karst processes were proposed by White (1969) and expanded in subsequent revisions (White, 1977; White, this volume)Some recent landmark papers on speleogenesis include those of Ford and Ewers (1978), Palmer (1984,1991), and White (1976)For further information on karst, see the references cited in the Introduction to this volume

The development of basin-scale conceptual models of the active-flow conduit system, 1999, Meiman J. , Ryan M. T.

The sedimentary records in Mediterranean rockshelters and caves: Archives of environmental change, 2001, Woodward J. C. , Goldberg P. ,
It is important to develop rigorous methods and robust conceptual models for the interpretation of rockshelter and cave sediment records so that the cultural sequences they contain can be considered in their proper environmental context. Much of what we know about the prehistory of the Mediterranean region and adjacent areas has largely been pieced together from materials excavated from sedimentary sequences in these environments. The rockshelters and caves of the region form important environmental and sedimentary archives. Recent work has begun to consider if the remarkable climatic variability evident in the high resolution lacustrine and ice core records is manifest in the rockshelter and cave sediment records of the area, In this context, the two main characteristics of a rockshelter or cave site which control its usefulness as an archive of environmental change are the temporal resolution of the sedimentary record and the environmental sensitivity of the site. Many rockshelters and caves can be described as either Active Karst Settings (AKS) or Passive Karst Settings (PKS) and site type is an important influence on climatic sensitivity with a direct influence upon the usefulness of the sedimentary sequence as a proxy record of climate change. It is now clear that some sites may preserve detailed paleoclimatic records and the climatic signal may be represented by distinctive suites of micromorphological features, by variations in the input of allogenic sediment, or by fluctuations in the mineral magnetic properties of the fine sediment fraction. It can be argued that data derived from the analysis of bulk coarse-grained samples often lacks the stratigraphic resolution and environmental sensitivity that can be obtained from other approaches. The most favorable sites for detailed paleoclimatic reconstruction appear to be in active karst settings such as Theopetra Cave (Greece) and Pigeon Cave (Morocco) where micromorphological analyses offer insights into the stratigraphic record that are not otherwise obtainable. The temporal resolution of a site can only be established through a rigorous stratigraphic analysis and a comprehensive dating program. These are fundamental considerations in the study of rockshelter sediment records, especially when attempting to correlate between sites and draw comparisons with other proxy records of environmental change derived from sedimentary environments with rather different characteristics. Rockshelters and caves are part of a wider sediment system, and their investigation must be accompanied by detailed geomorphological, sedimentological, paleoecological, and geochronological studies of the off-site Quaternary record.

A decision-logic framework for investigating subsidence problems potentially attributable to gypsum karstification, 2002, Lamontblack J. , Younger P. L. , Forth R. A. , Cooper A. H. , Bonniface J. P. ,
Karst regions, especially gypsum ones, are prone to subsidence; this can cause severe problems in urban areas. However, this subsidence may have causes other than active karstification. A decision-logic framework designed to tackle this issue is presented. It comprises subsidence description identification of causal mechanisms; construction and evaluation of conceptual models; evaluation and parameterization of fundamental processes and development of a management strategy. This framework is applied to an area of active subsidence in the UK underlain by gypsiferous rocks. In this example, particular attention is paid to the evaluation of gypsum dissolution using four criteria: presence of evaporite; presence of undersaturated water; energy to drive water through the system; and an outlet for the water. Gypsum palaeokarst was identified from borehole evidence and contemporary karstification is indicated by groundwaters containing up to 1800 mg/l of dissolved sulphate. Strontium/sulphate ratios enabled the discrimination of gypsum and non-gypsum-derived sulphate ions and correlation with the hydrostratigrapby. Continuous measurement of groundwater levels showed differential potentiometric surfaces between stratigraphical horizons and indicated a complex pattern of groundwater movement. Integration of these data in a physically and chemically based groundwater model, incorporating a void evolution capability, is suggested. (C) 2002 Elsevier Science B.V. All rights reserved

Patterns of dissolutional porosity in carbonate rocks, 2003, Palmer, A. N.

This paper reviews the hydrochemical processes that determine the patterns of caves and other solutional features within carbonate rocks. The model presented relies on the functional relationships expressed by chemical mass balances, flow equations, and kinetic expressions for dissolution rate. Although it shares many aspects of purely conceptual models and is backed by field evidence, its quantitative basis places it into the realm of analytical models.
The conclusions merely summarize earlier work (mainly Palmer, 1981, 1991). Solutional enlargement of caves and other karst features is highly selective in water that is close to equilibrium with dissolved carbonate minerals, enlarging only the most favorable openings – i.e. those that transmit the greatest discharge. This is characteristic of long flow paths within a typical karst aquifer. In contrast, solutional enlargement will be rather uniform along many competing flow paths where there is (1) high discharge, (2) sustained steep hydraulic gradients, (3) short flow paths, or (4) local renewal of aggressiveness by mixing, oxidation of sulfides, etc. These conditions produce maze caves and epikarstic networks. In general, this condition prevails if Q/rL > 0.001 cm/sec (tubes), or /bL > 0.001 cm/sec (fissures), where Q = discharge, r = tube radius, b = long dimension of fissure cross section, and L = distance of flow from where the initial aggressive solution comes in contact with the carbonate rock.


Conceptual models for karstic aquifers, 2003, White, W. B.

Karstic carbonate aquifers are extremely heterogeneous with a distribution of permeability that spans many orders of magnitude. They often contain open conduit flow paths with hydraulic characteristics more like surface streams than ground water. Karstic carbonate aquifers have highly efficient interfaces with surface water through swallets and springs. Characterizing parameters include: area of ground-water basin, area of allogenic recharge basins, conduit carrying capacity, matrix hydraulic conductivity, fracture hydraulic conductivity, conduit system response time, and conduit/fracture coupling coefficients. The geologic setting provides boundary conditions that allow the generalized conceptual model to be applied to specific aquifers.


Composite transfer functions for karst aquifers, 2003, Icjukic V. , Jukic D. ,
Linear transfer functions have been extensively used in hydrological studies. Generally, we support this conclusion: rainfall-runoff models based on the convolution between rainfall rates and a nonparametric transfer function (NTF) are not successful at simulating karst spring discharges during long recession periods. The tails of identified transfer functions have irregular shapes and they are not accurate physical representation of the transport through a karst system. Irregularities are the result of unavoidable errors in input and output time series and simplifications made by considering the system as linear and time invariant. This paper deals with a new form of the transfer functions for karst aquifers, the so-called composite transfer function (CTF). The CTF simulates discharges by two transfer functions adapted for the quick flow and the slow flow hydrograph component modeling. NTF is responsible for the quick flow component. The slow flow component is modeled by a parametric transfer function that is an instantaneous unit hydrograph mathematically formulated and defined from a conceptual model. By using the CTF, the irregular shape of the tail of the identified transfer function can be avoided, and the simulation of long recession periods as well as the simulation of a complete hydrograph becomes more successful. The NTF, the Nash model, the Zoch model and other similar conceptual models can be considered separately as simplified forms of the CTF. The rainfall-runoff model based on the convolution between rainfall rates and the CTF was tested on the Jadro Spring in Croatia. The results of the application are compared with the results obtained by applying NTFs independently. (C) 2003 Elsevier Science B.V. All rights reserved

An example of sedimentary filling in the chalk karst of the Western Paris Basin: Characterization, origins and hydrosedimentary behaviour, 2004, Laignel B. , Dupuis E. , Rodet J. , Lacroix M. , Massei N. ,
The Petites Dales cave is a favourable site for studying the sedimentary fillings of the chalk karst of the Western Paris Basin. Our study is based on the lithological characterization of karstic sediments and mineralogical and chemical comparisons between these sediments and the likely sedimentary sources (insoluble residue of chalk, clay-with-flints, loess). Our results show that there are three main families of sediment in the Petites Dales karst: brown clayey silts, beige silts, pale beige silts. The karst sediments essentially originate in the mechanical erosion of loess. The insoluble residue of chalk, coming from the chalk weathering, is only located in the brown clayey silts, and constitutes a weak amount of this sediment type. According to these results, we propose three conceptual models of hydro sedimentary behaviour of the Petites Dales karstic system that could have resulted in such an intra-karstic deposition sequence

Groundwater in Karst: Conceptual Models, 2004, Worthington S. R. H. , Smart C.

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