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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 geology is the study of the planet earth-the materials of which it is made, the processes that act on these materials, the products formed, and the history of the planet and its life forms since its origin. geology considers the physical forces that act on the earth, the chemistry of its constituent materials, and the biology of its past inhabitants as revealed by fossils. clues on the origin of the planet are sought in a study of the moon and other extraterrestrial bodies. the knowledge thus obtained is placed in the service of man-to aid in discovery of minerals and fuels of value in the earth's crust, to identify geologically stable sites for major structures, and to provide foreknowledge of some of the dangers associated with the mobile forces of a dynamic earth [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 methodology (Keyword) returned 82 results for the whole karstbase:
Showing 1 to 15 of 82
Remarks on the significance of experiences in karst geodynamics., 1964, Renault Philippe
Distinction is made between the experiment which "demonstrates" having an argumentative value; and the experiment which "questions" nature by isolating one factor and by determining the mode of its action. The concept of experiment in geology and in geodynamics and the distinctions between geodynamics and geophysics are discussed. Karstic geodynamics considers the action of fluids; mainly liquids; on a soluble rock. It is a science bordering the different branches of geochemistry, hydrology, the mechanics of rocks, and geophysics. Researches in karstic geodynamics are based upon measurements obtained through field surveys, or upon the utilization of a subterranean laboratory. However, in the laboratory this hardly surpasses the stage of experimental demonstration. A series of simple experiments are enumerated to exemplify the above statement, like the one where the attack of a diluted acid on a soluble rock is utilized, in order to enable us to classify the major problems encountered in karstic corrosion. The last chapter discusses the bicarbonate equilibriums of Ca-CO2. Experiment furnishes the empiric criterion on which scientific theory is founded. Each discipline has its own methodology dependent on the object under study having experimental criteria of different nature. This is particularly true in case of such distant phenomena which no longer have a common ground with human dimensions like space for astronomy or time for geology. In such cases the possibilities of "instrumental" experimentations are very limited. After a brief recollection of the principles of experimental procedure and the history of the experiments attempted by geodynamicians (tectonics, geomorphology, etc.) we will analyze several methods of investigation and by relying exactly on the example of karstic corrosion we shall determine those which have a value for the science of karstology.

Symposium Abstract: Leaching of Soil and Rock samples from two Northern European cave sites - Methodology and preliminary results, 1997, Tooth A. F.

Risk assessment methodology for karst aquifers .2. Solute-transport modeling, 1997, Field Ms,
Ground-water flow and solute-transport simulation modeling are major components of most exposure and risk assessments of contaminated aquifers. Model simulations provide information on the spatial and temporal distributions of contaminants in subsurface media but are difficult to apply to karst aquifers in which conduit flow is important. Ground-water flow and solute transport in karst conduits typically display rapid-flow velocities, turbulent-flow regimes, concentrated pollutant-mass discharge, and exhibit open-channel or closed-conduit how Conventional groundwater models, dependent on the applicability of Darcy's law, are inappropriate when applied to karst aquifers because of the (1) nonapplicability of Darcian-flow parameters, (2) typically nonlaminar flow regime, and (3) inability to locate the karst conduits through which most flow and contaminant transport occurs. Surface-water flow and solute-transport models conditioned on a set of parameters determined empirically from quantitative ground-water tracing studies may be effectively used to render fate-and-transport values of contaminants in karst conduits. Hydraulic-flow and geometric parameters developed in a companion paper were used in the surface-water model, TOXI5, to simulate hypothetical slug and continuous-source releases of ethylbenzene in a karst conduit. TOXI5 simulation results showed considerable improvement for predicted ethylbenzene-transport rates and concentrations over qualitative tracing and analytical ground-water model results. Ethylbenzene concentrations predicted by TOXI5 simulations were evaluated in exposure and risk assessment models

RISK ASSESSMENT METHODOLOGY FOR KARST AQUIFERS: (2) SOLUTE-TRANSPORT MODELING, 1997, Field Ms,

Risk assessment methodology for karst aquifers .1. Estimating karst conduit-flow parameters, 1997, Field Ms, Nash Sg,
Quantitative ground-water tracing of conduit-dominated karst aquifers allows for reliable and practical interpretation of karst ground-water flow. Insights into the hydraulic geometry of the karst aquifer may be acquired that otherwise could not be obtained by such conventional methods as potentiometric-surface mapping and aquifer testing. Contamination of karst aquifers requires that a comprehensive tracer budget be performed so that karst conduit hydraulic-flow and geometric parameters be obtained. Acquisition of these parameters is necessary for estimating contaminant fate-and-transport. A FORTRAN computer program for estimating total tracer recovery from tracer-breakthrough curves is proposed as a standard method. Estimated hydraulic-flow parameters include mean residence time, mean flow velocity, longitudinal dispersivity, Peclet number, Reynolds number, and Froude number. Estimated geometric parameters include karst conduit sinuous distance, conduit volume, cross-sectional area, diameter, and hydraulic depth. These parameters may be used to (1) develop structural models of the aquifer, (2) improve aquifer resource management, (3) improve ground-water monitoring systems design, (4) improve aquifer remediation, and (5) assess contaminant fate-and-transport. A companion paper demonstrates the use of these hydraulic-flow and geometric parameters in a surface-water model for estimating contaminant fate-and-transport in a karst conduit. Two ground-water tracing studies demonstrate the utility of this program for reliable estimation of necessary karst conduit hydraulic-flow and geometric parameters

RISK ASSESSMENT METHODOLOGY FOR KARST AQUIFERS: (1) ESTIMATING KARST CONDUIT-FLOW PARAMETERS, 1997, Field Ms, Nash Sg,

Hydrogeological exploration of the Rjecina river spring in the Dinaric Karst., 1997, Biondic B. , Dukaric F. , Kuhta M. , Biondic R.
The Rjecina spring is one of the major springs in the Dinaric Karst. It appears at the contact between permeable carbonate and impermeable clastic rocks, with a discharge of up to 120 m3/s but it dries up during the dry seasons. The spring occurs close to the town of Rijeka, 325 m above sea level and offers an outstanding opportunity to cover gravitationally the public water demand of a town of about 200 000 inhabitants, and turistic needs of the whole region. This hydrogeological research project is a part of efforts to solve the problems of water deficiency during the dry summer seasons up to a maximum of three months. It was necessary to enter the parts of karst aquifer that are active in time of any outflow from the Rjecina spring by complex geological, hydrogeological and geophysical exploration accompanied with deep exploratory boreholes. During earlier explorations, it was determined that there are no active inflows in the immediate hinterland of the spring and that it is necessary to discover the inflows from other karst structures, that behave as retentions of karst springs in the zones of permanent discharge. The presence of multiple overthrusted structures in the zone around the spring site suggests the existence of deep zones of water retention, which may be reached by an access gallery from the Rjecina canyon. This work represents a substantial change in the exploration methodology for Dinaric Karst aquifers, because it directs the researchers toward deep, unknown retention spaces, which contain large reserves of high-quality groundwater outside urban areas.

Vertical leakage and vertically averaged vertical conductance for karst lakes in Florida, 1998, Motz L. H. ,
In the karst lake district in peninsular Florida in the southeastern United States, as many as 70% of the lakes lack surface outlets, and groundwater outflow is an important part of the water budgets of these: lakes. For 11 karst lakes in the Central Lake District, vertical leakage from the lakes to the upper Floridan aquifer averages 0.12 to 4.27 m yr(-1). The vertically averaged vertical conductance K-v/b, a coefficient that represents the average of the vertical conductances of the hydrogeologic units between the bottom of a lake and the top of the upper Floridan aquifer, was determined to range from 0.0394 to 1.00 yr(-1) for these lakes. For six of the lakes, various hydraulic parameters previously calculated by other investigators are shown to be equivalent to the K,ib values calculated in this study. If K-v/b is determined for a lake, then vertical leakage can be estimated for other conditions of lake stage and hydraulic head in the upper Floridan aquifer, using K-v/b for the lake and Darcy's equation written for vertical flow. The methodology described in this paper for quantifying K-v/b, which requires only limited data (i.e., vertical leakage, lake stage, and hydraulic head in the upper Floridan aquifer), could be used to investigate the apparent association between relatively large K-v/b values and lake level instabilities at some lakes in the Central Lake District and similar hydrogeologic settings. This methodology for calculating vertical leakage is applicable to the Central Lake District in Florida and to other similar lake and groundwater systems

Contribution to knowledge of gypsum karstology, PhD thesis, 1998, Calaforra Chordi, J. M.

The objective of this study was not to establish a definitive judgement regarding a topic for which very little previous information was available, but rather to open new routes for research into karst by means of a particularized analysis of some of the factors involved in the speleogenesis of gypsiferous materials. The main obstacle to the attainment of this goal has been the scientific community's lack of interest in karst in gypsum, particularly in our country, until the nineteen eighties. To overcome this neglect it was decided, in my opinion quite correctly, to extend the bounds of the study as far as possible, so that the information obtained from the contrast found between the most important worldwide zones of karst in gypsum could be applied to the gypsiferous karst in our country, and in particular, to the most significant, the karst in gypsum of Sorbas.
This is the justification for the numerous references in the text to the gypsiferous karst and cavities in gypsum that are most relevant in Spain (Sorbas, Gobantes, Vallada, Archidona, Estremera, Baena, the Ebro Basin, Estella, Beuda, Borreda, etc.) and also to the best-known gypsiferous karsts worldwide (Podolia, Secchia, Venna del Gesso Romagnolo, Sicily and New Mexico). By means of these comparisons, the initial lack of information has been overcome.
The study is based on three central tenets, which are interrelated and make up the first three chapters of this report. The first consideration was to attempt to characterize the particular typology of gypsiferous karst from the geological (both stratigraphic and structural) point of view. This chapter also provides an introduction to each of the gypsiferous karsts examined. The second chapter is dedicated to the geomorphology of gypsiferous karst, under both superficial and subterranean aspects. It is important to note that the study of a gypsiferous karst from the speleological point of view is something that may seem somewhat unusual; however, this is one of the points of principle of this paper, the attempt to recover the true meaning of a word that has historically been unfairly condemned by a large part of the Spanish scientific community. Thirdly, a detailed study has been made of the hydrochemistry of the most important gypsiferous karsts in our region, together with the presentation of a specific analytical methodology for the treatment of the hydrochemical data applicable to the gypsiferous karst.
Geological characterization of gypsum karst
In the characterization of karst in gypsum, the intention was to cover virtually all the possibilities from the stratigraphic and structural standpoints. Thus, there is a description of widely varying gypsiferous karsts, made up of Triassic to Miocene materials, some with a complex tectonic configuration and others hardly affected by folding. The gypsiferous karsts described, and their most significant geological characteristics, are as follows:
Karst in gypsum at Sorbas (Almeria): composed of Miocene gypsiferous levels with the essential characteristic of very continuous marly interstrata between the layers of gypsum, which decisively affect the speleogenesis of the area. The gypsum layers have an average thickness of about 10 m and, together with the fracturing in the zone, determine the development of the gypsiferous cavities. These are mainly selenitic gypsum - occasionally with a crystal size of over 2 m - and their texture also has a geomorphologic and hydrogeologic influence. This area is little affected by folding and so the tectonic influence of speleogenesis is reduced to the configuration of the fracturing.
The Triassic of Antequera (Malaga): this is, fundamentally, the gypsiferous outcrop at Gobantes-Meliones, originating in the Triassic and located within the well-known "Trias" of Antequera. It is made up of very chaotic gypsiferous materials containing a large quantity of heterometric blocks of varied composition; the formation may be defined as a Miocene olitostromic gypsiferous breccia that is affected by important diapiric phenomena. The presence of hypersoluble salts at depth is significant in the modification of the hydrochemical characteristics of the water and in the speleogenetic development of the karst.
The Triassic of Vallada (Valencia): Triassic materials outcrop in the Vallada area; these mainly correspond to the K5 and K4 formations of the Valencia Group, massive gypsum and gypsiferous clays. The influence of dolomitic intercalations in the sequence is crucial to the speleogenesis of the area and this, together with intense tectonic activity, has led to the development in this sector of the deepest gypsiferous cavity in the world: the "Tunel dels Sumidors". As in the above case, the presence of hypersoluble salts at depth and the varied lithology influence the variations in the hydrodynamics and hydrochemistry of the gypsiferous aquifer.
Other Spanish gypsum karsts: this heading covers a group of gypsiferous areas and cavities of significant interest from the speleogenetic standpoint. They include the area of Estremera (Madrid), with Miocene gypsiferous clays and massive gypsum arranged along a large horizontal layer; this has produced the development of the only gypsiferous cavity in Spain with maze configuration, the Pedro Fernandez cave. The study of this cave has important hydrogeological implications with respect to speleogenesis in gypsum in phreatic conditions. The Baena (Cordoba) sector, in terms of its lithology, is comparable to the "Trias de Antequera". Here, the cavities developed in gypsiferous conglomerates, following structural discontinuities have enabled contact between carbonate and gypsiferous levels, and so we may speak of a mixed karstification: a karst in calcareous rocks and gypsum. The karst of Archidona (Malaga) is similar to that of the Gobantes-Meliones group and is significant because of the geomorphologic evolution of the karst, which is related to the diapiric ascent of the area and the formation of karstic ravines. The karst in the Miocene and Oligocene gypsum of the Ebro Basin (Zaragoza), has been taken as a characteristic example of a gypsiferous karst developed under an alluvial cover, with the corresponding geomorphological implications in the evolution of the surface landforms. In the gypsiferous area of Borreda (Barcelona), the presence of anhydritic levels in the sequence might have influenced the speleogenesis of its cavities. The cavity of La Mosquera, in Beuda (Girona), developed in massive Paleogene gypsum. This is the only Spanish example of a phreatic gypsiferous cavity developed in saccaroid gypsum, which is related to the particular subterranean morphology discovered. Finally, this group includes other Spanish gypsiferous outcrops visited during the preparation of this report, the references to which may be found in the relevant chapters.
Karst in gypsum in Europe and America: In order to complete the study of karst in gypsum, and with the idea of using all the available data on the karstology of gypsiferous materials for comparative studies of data for our country, a complementary activity was to define the most significant geological characteristics of the most important gypsiferous karsts in the world. An outstanding example is the gypsiferous karst at Podolia (Ukraine), developed in microcrystalline Miocene gypsum which has undergone block tectonics related to the collapse of the Precarpatic foredeep. This gypsum provides interesting data on speleogenesis in gypsiferous materials, as its evolution is related to the confining of the only gypsiferous stratum (of 10 to 20 m depth) producing interconnected labyrinthine galleries of over 100 km in length. Another well-known karst in gypsum is the one located at "Venna del Gesso Romagnolo" (Italy), in the Bologna region, with a lithology that is very similar to that which developed at Sorbas, but with the difference that it underwent more intense tectonics with folding and fracturing of the Tertiary sediments of the Po basin. In the same Italian province, in "L'alta Val di Sec-chia", there are outcrops of karstified Triassic materials which correspond to the formation of Burano, composed of gypsum and anhydrite with hypersoluble salts at depth and very notable diapiric phenomena. The study of this area has been used for a comparative analysis - geomorphology and hydrogeochemistry - with the Spanish gypsiferous karsts developed in Triassic levels. The third Italian gypsiferous karst to be considered is the one developed in Sicily, which has extensive Messinian outcrops of microcrystalline and selenitic gypsum as well as a great variety of lithologic types within the gypsiferous sequence, which we term the "gessoso solfifera" sequence. This gypsiferous karst is especially interesting from the geomorphologic standpoint due to the great quantity and variety of present superficial karstic forms. This has also served as a guide for the study of Spanish gypsiferous karsts. Finally, considering the relation between climatology and the development of karstic forms, we have also studied the karst in gypsum in New Mexico, where there is an extensive outcrop of Permian gypsum, both micro and macrocrystalline, situated on a large platform almost unaffected by deformation, and where the conditions of aridity are very similar to those found in the gypsiferous karst of Sorbas.
Geomorphological characterization of gypsum karst
From the geomorphological standpoint, the intention is to give an overview of the great variety of karstic forms developed in gypsum, traditionally considered less important than those developed in carbonate areas. This report shows this is not the case.
The theory of Convergence of Forms has been shown to be an efficient tool for the study of the morphology of karst in gypsum. Here, its principles have been used to provide genetic explanations for various gypsiferous forms derived from carbonate studies, and for the reverse case. In fact, studying a karst in gypsum is like having available a geomorphological laboratory where not only are the processes faster but they are also applicable to the karstology of carbonate rocks.
A large number of minor karstic forms (Karren) have been identified. The most important factors conditioning their formation are the texture of the rock, climatology and the presence of overlying deposits. The first, particularly, is largely responsible for determining the abundance of certain forms with respect to others. Thus, Rillenkarren, Trittkarren and small "kamenitzas" are more frequently found in microcrystalline and sandstone gypsum (for example, karst in gypsum in Sicily (Italy) and Va-llada (Valencia, Spain). Others seem to be more exclusive to selenitic gypsum, such as exfoliation microkarren, or are closely related to the climatology of the area (Spitzkarren develops from the alteration of gypsum in semiarid conditions). Others are related either to the presence of developed soil cover (Rundkarren, using Convergence of Forms), or to their specific situation (candelas and Wallkarren around dolines and sinkholes) or to the microtexture of the gypsum and the orientation of the 010 and 111 crystalline planes and twinning planes for the development of nanokarren.
The tumuli are the most peculiar forms of the Sorbas karst in gypsum, though they have also been identified in other gypsiferous karsts (Bolonia, New Mexico, Vallada, etc.). These are subcircular domes of the most superficial layer of the gypsum. Their formation has been related to processes of precipitation-solution and of capillary movement through the gypsiferous matrix. Their extensive development is largely determined by the climatology of the area and by the structural organization. It is therefore clear that the best examples are found in the karst of Sorbas due to the abrupt changes in temperature and humidity that occur in a semiarid climate, and because of the horizontality of the gypsiferous sequence.
Karst in gypsum and its larger exokarstic forms, apart from being climatically determined, also depend on the structural state and lithological determinants of the area. Thus, it is possible to differentiate between gypsiferous karsts where the lithology, together with erosive breakup, is more important (Sorbas and New Mexico) and others where confining hydraulic conditions persist (Estremera and Podolia). In other cases, tectonics has played a significant modelling role, and there is a clear possibility of an inversion of the relief (Bolonia or Sicily) or of the effect of diapiric processes (Secchia, Vallada, Antequera). The typological diversity of the dolines is obviously also related to these premisses. Another example is the relation existing between carbonate precipitation and gypsum solution, as evidenced in contrasting examples (Bolonia versus Sorbas).
Subterranean karstic forms have been examined from a double perspective: the morphology of the passages and the mineralization within the cavities. With respect to the former, a noteworthy example is the interstratification karst of Sorbas, where subterranean channels have developed during two well-differentiated phases, the phreatic and the vadose. The first was responsible for the formation of the small proto-galleries, currently relicts that are observable as false dome channels in the bottom of the gypsiferous strata. The second, with an erosive character, enabled the breakup of the marly interstrata and the formation of the large galleries found today. Other aspects considered include the speleogenetic influence of the presence of calcareous intercalations in the gypsiferous sequence (Vallada karst), gypsiferous agglomerates (Baena karst), anhydrite (Rotgers karst), suffusion processes (Sorbas karst) and the importance of condensation.
Spelothemes in gypsiferous cavities have been approached with special concern for gypsiferous speleothemes, in particular those which, due to their genetic peculiarity or to the lack of previous knowledge about them, are most significant. Among these are gypsum balls, with phenomena of solution, detritic filling, capillarity and evaporation; gypsum hole stalagmites, where the precipitation-solution of the gypsum controlling the formation of the central orifice is related to the previous deposit of carbonate speleothemes; gypsum trays that mark the levels of maximum evaporation; gypsum dust, determined by abrupt changes in temperature and humidity in areas near the exterior of gypsiferous cavities. All of these are characteristic of, and practically exclusive to, gypsiferous karsts in semiarid ztenes such as Sorbas and New Mexico.
Karst in gypsum has been morphologically classified with reference to the previously-mentioned criteria: the presence and typology of epigean karstic forms, both macro and microform; the typology of hypogean karstic forms (passages) and the type of speleothemes within the cavities (gypsiferous or carbonate). All these variables are clearly influenced by climatology, and so a study of the geomorphology of gypsiferous karst is seen to be an efficient tool for the analysis of the paleoclimatology of an area.
Hydrogeochemical characterization of gypsum karst
The hydrogeochemical characterization of karst in gypsum was approached in two stages. The first one was intended to establish themodels to be applied to the hydrochemistry approach, while the second provided various examples of hydrochemical studies carried out in gypsiferous karsts.
The theoretical framework which has been shown to be most accurate with respect to the formulation of chemical equilibria in water related to gypsiferous karst is the Virial Theory and the Pitzer equations.
For this study, we used a simplification of these equations as far as the second virial coefficient by means of a simple, polynomial variation to obtain the equilibrium state of the water with respect to the gypsum, for an ionic strength value greater than 0.1 m and temperatures of between 0.5 and 40 "C. This was the case of the gypsiferous karsts found to be related to hypersaline water at depth (Vallada, Gobantes-Meliones, Poiano). In the remaining situations, where the ionic strength was below 0.1 m, only the theory of ionic matching was used.
The hydrochemical study of the gypsiferous karst of Gobantes-Meliones (Malaga) led to the hypothesis of the possible influence of hypersaline water on karstification in gypsum. Using theoretical examples of the mixing of water derived both from hypersaline water and from water related only to the gypsiferous karst, it was shown that above a percentage content of 0.1:0.9 of saline and sulphated water, the mixture is subsaturated with respect to gypsum and other minerals. On reaching percentages greater than 0.5:0.5, values of oversaturation are again found. This could mean that the contact between sulphated and hypersaline water is a karstification zone in gypsum at depth.
In the gypsiferous karst at Salinas-Fuente Camacho (Granada), a study has been made of the hydrochemical influence of dolomitic levels in the sequence by means of the analysis of the hydrochemical routes between hydraulically-connected points. The generic case of mass transfer in this gypsiferous aquifer implies a precipitation of calcite which is in-congruent with dolomitic solution, proving that the process of dedolomitization in gypsiferous aquifers with an abundance of dolomitic rocks can be an effective process. In situations of high salinity, with contributions of hypersaline water, the process may be inverted, such as occurs in coastal carbonate aquifers influenced by the fresh-saltwater interface.
The gypsiferous aquifer of Sorbas-Tabernas (Almeria) provides the best case of karstification in gypsum in Spain; the hydrochemical study carried out has been used as an example of karstification in gypsum completely uninfluenced by sodium-chloride facies. It is shown, from the hydrochemical similarities between the different sectors, that the uniformity of the flow from the system main spring (Los Molinos) responds to the delayed hydraulic input through the overlying post-evaporitic materials and to the pelitic intercalations of the gypsiferous sequence. The aquifer is partially semiconfined, a situation which is comparable to the onset of the karstification stage, while the area of the Sorbas karst, strictly speaking, bears no hydriaulic relation to the rest of the system, behaving like a free aquifer intrinsically related to the epikarstic zone. This fact is demonstrated by the hydrochemical differences between the main spring and those related to gypsiferous cavities.
Apart from the general study of the Sorbas-Tabemas aquifer, a study was also made of the hydrochemical-time variations within cavities, and in particular within the Cueva del Agua, where it is possible to observe particular processes affecting karstification in gypsum, such as the precipitation of carbonates on the floor of the cavity which produce, in that area, a greater solution of gypsum (the phenomenon of hyperkarstification). Furthermore, the temporal evolution of the chemistry of the cavity, along 800 m of subterranean flow through its interior, shows the existence of inertial sectors where the variations were less abrupt. Only in the case of particular sectors, related to sporadic hydriaulic contributions or to the proximity to points of access., was a notable seasonal influence detected.
A similar hydrochemical study was carried out in the karst of Vallada (Valencia), along the cavity of the Tunel dels Sumidors. The chemistry here was compared with that of the springs of Brolladors (whose water rapidly infiltrates into the cavity) and Saraella (a saline resurgence of the whole system). Unexpected increases in the ionic content of certain salts (sulphates and chlorides) were detected during periods of increased flow; these were interpreted as the effect of the recharging of the Saraella spring arising from the immediate contribution of rapidly circulating sulfated water coming from the cavity and the subsequent mobilization of interstitial water with an ionic content higher than the characteristic level of the spring.
We present as a hypothesis the idea that, in addition to the hydrogeochemical processes described that can affect the evolution of a gypsiferous karst, the processes of sulphate reduction also influence karstification in gypsum, at least during the earliest stages. Some examples such as the presence of gypsum with abundant organic matter reprecipitated into phreatic channels (Sorbas) or veins of sulphur related to gypsiferous karsts (Podolia, Sicily) lend support to this idea.
Studies of the solution-erosion of gypsum have been performed by physical methods (tablets and M.E.M.) showing that the solution-erosion of gypsum within cavities is minimal (0.03 mm/ year) compared to that existing in the exterior (0.3 mm/year). The speleogenetic effect of condensation within the cavities has also been shown, with solution-erosion rates of 0.005 mm/year to be like the equivalent surface lowering. These data correspond to the karst in gypsum at Sorbas, where, additionally, a study about the time variation of the solution-erosion was carried out. It was found that the process is not continuous but clearly sporadic. During periods of torrential rain, the solution-erosion ranges from a weight loss of 400 mg/cm2/year on the surface of the karst to 75 mg/cm2/year inside the caves, while during the rest of the year the weight loss was barely 1 mg/cm2/year. The physical methods were compared with the results obtained from chemical methods, and it was found that, in general, higher values were obtained with the former (10-20% higher when weighted for the rainfall during the measuring periods). Thus it is reasonable to consider that the erosive process is more marked than was at first assumed.
In total, three cavity tracing experiments were carried out, all with fluoresceine, two of them in Cueva del Agua in Sorbas (during periods of high and low water levels) and the other in Tunel dels Sumidors in Vallada. At the first site, the comparison of the two tracing tests reveals a differential hydrodynamic behaviour of the cavity for the two contrasting situations; periods of high water input and periods of low rainfall. This behaviour is characteristic of well developed karstic aquifers, where the hydrodynamic effect of the circulation of water through small channels or, in this case, through the gypsiferous matrix and interbedded marly layers, seems to be more important under conditions of low hydraulic input than when rainfall is abundant. The two situations tested seem to confirm that the Cueva del Agua system, an epikarstic aquifer, which is representative of karstification in gypsum, has scarce retentive power and so large volumes of precipitation are totally discharged via the spring within a few days. However, the explanation of the small but continuous flow from the base of the cavity requires the inclusion of other factors in the interpretation. In this case, the flow seems to be fairly independent of rainfall and attributable to other processes, in addition to the previously described ones, such as the retentive power of the gypsiferous matrix and the marly interstrata. These might include the high degree of condensation measured over long periods, both on the surface of the karst in gypsum and within the cavities. In the case of the Tunel dels Sumidors, a highly irregular response was found, despite the fact that the coefficient of dispersivity was found to be 0.4. This value is similar to that obtained for the karst in gypsum at Sorbas in response to low water conditions, and so, here too, one might assume the influence of greater than expected flow-retaining processes, between the entry and exit points. Doubtless the karstic system of the Tunel dels Sumidors is more complex than was initially expected and in fact, the irregularity reflected by the fluoresceine concentration curve over time implies the existence of other factors to explain the diversity of the relative maxima obtained. Firstly, the presence of numerous Triassic clay intercalations might delay the flow, in addition to retaining a certain quantity of fluoresceine by ionic exchange. There is also a possibility that the flow is dispersed through a network of small conduits and pores, due to the permeability of the gypsiferous matrix. Finally, we cannot discount the possible existence of a deep-level input which, in this case, would be responsible for the variation in the flow and the chemical composition. This set of suppositions, as a whole, would explain the fact that the response of the spring to tracing is so irregular, even though we cannot achieve a definition of the qualitative influence of each one on the hydrodynamics of the system.
In order to verify some of the above hypotheses, particularly those referring to the process of condensation within cavities, an experiment was designed, consisting of a microtracing test at some points where condensation had been detected within the Cueva del Agua at Sorbas. The test produced a range of condensation flow speed values of 0.2 to 30 cm/hour and shows that, in those sections where the presence of condensation flow is visually apparent, there is a rapid dispersion of the colourant. However, it also shows that at points where there is no apparent condensation the process also occurs, but at a lower rate of efficiency. The importance of condensation within cavities has two aspects; firstly, speleogenetic, with the development of solution forms (cupolas) and deposit forms (capillarity boxwork); and secondly, hydrogeological, as this is the reason why certain processes (strong changes in temperature and humidity, multiple routes of airflow exchange with the exterior) may in themselves constitute a hydraulic contribution, of slight importance, but sufficient to explain a large part of the base flow (0.2 - 0.8 L/s) of a whole cavity system such as the Cueva del Agua in semiarid conditions.
With the intention of completing the analyses carried out in various karsts in gypsum, instruments were installed in the Cueva del Agua at Sorbas to measure, by continuous registration, some important physico-chemical parameters that might provide additional data on the hydro-geologic behaviour of this gypsiferous karst, especially at the level of the epikarstic zone. The parameters of temperature and water conductivity were considered most important, due to their singular behaviour patterns. During the experiment there were two periods of rainfall that modified the chemistry of the cavity, one of 30 mm in two days and another of 200 mm (almost the annual total) in four days. In the second case, which was much more extreme, a very significant increase in water temperature (up to 7 °C during the initial period of high water flow) was detected, while conductivity fell. But suddenly, when the minimum conductivity was reached, the temperature dropped sharply by 6-7 °C to return to the base temperature of the cavity. Subsequently, the temperature again stabilized at about 7 °C above the data recorded during the dry period. This behaviour pattern was not detected when the rainfall was slight. The explanation for this dual behaviour observed is fundamentally based on the quantity of rainfall and on the differences between the exterior air temperature, the temperature of interstitial water and the temperature recorded in the spring during high water flow. When water temperature in the cavity during high water flow is higher than the base temperature recorded in the period immediately before, it means that the interstitial water does not mobilize. However, when at any time the two temperatures coincide, one might suppose that there might have existed a process of mobilization of the water previously resident in the rock, by a piston effect, but in the unsaturated zone. On the other hand, the temporal variations of these parameters during the months following periods of high rainfall have enabled us to detect the existence of distinct periods during the return to normal cavity conditions. By carefully examining the decrease curve of water temperature inside the cavity while conductivity regained its maximum stable value, two periods may be differentiated. The first may be termed the "inertial influence period", when the rainfall occurring removes all signs of natural variation in the cavity. Thus, the daily external influences are not clearly detectable and the curve is downward-sloping and asymptotic with no significant oscillations. In the second period, which ends with the total stabilization of the parameter at the level of the initial conditions, the asymptotic descent is seen to be affected by daily temperature variations. This is termed the "inertial recovery period", during which external variations start to have an effect on the interior of the cavity such that there is a progressive increase in the amplitude of the daily variation in water temperature, air temperature and relative humidity. This behaviour pattern of variation of these parameters during periods of high rainfall, might be extended to all karstic systems, varying only in magnitude and temporal extent.


Water circulation in karst and determination of catchment areas: example of the River Zrmanja, 1999, Bonacci O,
Karst hydrological investigation of the sinking stream problem of the River Zrmanja is presented. The aim of this analysis is to assess the feasibility of constructing three hydroelectric power plants (HEPP) along the River Zrmanja course. This paper presents a suitable and simple hydrological methodology that can be applied to scarce available data obtained on complex karat terranes. The paper presents a complex but common case of water circulation in a karst system. The primary objectives of the investigations were: (a) to analyse the underground karst connections, (b) to analyse discharge conditions along the River Zrmanja, and (c) to define variations in the catchment area along the River Zrmanja. The fact that the hydrological regime of the River Zrmanja is highly variable, due to the water losses along the open streamflow, strongly influenced the selection of the locations and heights of the HEPP dams. In spite of many hydrological, meteorological and hydrogeological measurements, the River Zrmanja catchment is insufficiently gauged. This dictates the use of a simple, empirically-based hydrological methodology. The Turc (1954) and Coutagne (1954) formulas were used in determination of annual total runoff. Using these simple hydrological methods, some important engineering answers were obtained. This is a first step towards application of sophisticated hydrological models, needing large amounts of reliable data

Groundwater protection zone delineation at a large karst spring in western Ireland, 2000, Deakin J,
Pouladower Spring is a large karst spring in County Clare, Ireland which is being considered for use as a public supply. Groundwater protection zones have been delineated as a water quality management strategy for the spring. The Irish national groundwater protection scheme methodology is adapted to take account of the hydrological and hydrogeological complexities of the karst regime. The catchment area for the spring is large (approximately 380 km2) and comprises the zones of contribution for two major outlets of water, the spring and the River Fergus. The actual zone of contribution to the spring varies with different water level conditions and the risk to the source from any point within the catchment, at any given time, is less than that for a conventional groundwater source. The catchment area is highly vulnerable, but dilution and sedimentation occurring in the lakes up gradient of the source, the high throughput, and the contribution from fissures outside the main flow conduits have helped maintain good water quality at the spring. The source is considered to be a combination of both groundwater and surface water as they are intricately inter-linked throughout the catchment. An Inner Protection Area is delineated which does not provide the 100-days travel time to the source required by the national scheme, as this would be impractically large and over-protective. Rather, it delineates the area of highest hydrogeological risk to the source and should allow the local authority sufficient time to act in the event of an accidental spill. A certain degree of microbial contamination is inevitable in a karst regime and treatment is essential, as it would be for a surface water source. The remainder of the catchment is classed as an Outer Protection Area. These protection areas are then combined with the vulnerability in a GIS to give groundwater protection zones which will be used by the planners, in conjunction with groundwater protection responses, to control potentially contaminating activities

Speleogenesis: Evolution of Karst Aquifers., 2000,
The aim of this book is to present advances made in recent decades in our understanding of the formation of dissolutional caves, and to illustrate the role of cave genetic ( speleogenetic ) processes in the development of karst aquifers. From the perspective of hydrogeology, karst ground water flow is a distinct kind of fluid circulation system, one that is capable of self-organization and self-development due to its capacity to dissolve significant amounts of the host rock and transport them out of the system. Fluid circulation in soluble rocks becomes more efficiently organized by creating, enlarging and modifying patterns of cave conduits, the process of speleogenesis. We can assert that karst ground water flow is a function of speleogenesis and vice versa . The advances in cave science are poorly appreciated in what may be termed ?mainstream hydrogeology?, which retains a child-like faith in flow models developed in the sand box. Many karst students also will not be aware of all emerging concepts of cave origin because discussions of them are scattered through journals and books in different disciplines and languages, including publications with small circulation. An understanding of principles of speleogenesis and its most important controls is indispensable for proper comprehension of the evolution of the karst system in general and of karst aquifers in particular. We hope this book will be useful for both karst and cave scientists, and for general hydrogeologists dealing with karst terranes. This book is a pioneer attempt by an international group of cave scientists to summarize modern knowledge about cave origin in various settings, and to examine the variety of approaches that have been adopted. Selected contributions from 44 authors in 15 nations are combined in an integrated volume, prepared between 1994 and 1998 as an initiative of the Commission of Karst Hydrogeology and Speleogenesis, International Speleological Union. Despite a desire to produce an integrated book, rather than a mere collection of papers, the editors' policy has not been directed toward unifying all views. Along with some well-established theories and approaches, the book contains new concepts and ideas emerging in recent years. We hope that this approach will stimulate further development and exchange of ideas in cave studies and karst hydrogeology. Following this Introduction, (Part 1), the book is organized in seven different parts, each with sub-chapters. Part 2 gives a history of speleogenetic studies, tracing the development of the most important ideas from previous centuries (Shaw, Chapter 2.1) through the early modern period in the first half of this century (Lowe, Chapter 2.2) to the threshold of modern times (W.White, Chapter 2.3). The present state of the art is best illustrated by the entire content of this book. Part 3 overviews the principal geologic and hydrogeologic variables that either control or significantly influence the differing styles of cave development that are found. In Chapter 3.1 Klimchouk and Ford introduce an evolutionary approach to the typology of karst settings, which is a taken as a base line for the book. Extrinsic factors and intrinsic mechanisms of cave development change regularly and substantially during the general cycle of geological evolution of a soluble rock and , more specifically, within the hydrogeologic cycle. The evolutionary typology of karst presented in this chapter considers the entire life cycle of a soluble formation, from deposition (syngenetic karst) through deep burial, to exposure and denudation. It helps to differentiate between karst types which may concurrently represent different stages of karst development, and is also a means of adequately classifying speleogenetic settings. The different types of karst are marked by characteristic associations of the structural prerequisites for groundwater flow and speleogenesis, flow regime, recharge mode and recharge/discharge configurations, groundwater chemistry and degree of inheritance from earlier conditions. Consequently, these associations make a convenient basis to view both the factors that control cave genesis and the particular types of caves. Lithological and structural controls of speleogenesis are reviewed in general terms in Chapters 3.2 (Klimchouk and Ford). Lowe in Chapter 3.3 discusses the role of stratigraphic elements and the speleo-inception concept. Palmer in Chapter 3.4 overviews the hydrogeologic controls of cave patterns and demonstrates that hydrogeologic factors, the recharge mode and type of flow in particular, impose the most powerful controls on the formation of the gross geometry of cave systems. Hence, analysis of cave patterns is especially useful in the reconstruction of environments from paleokarst and in the prediction and interpretation of groundwater flow patterns and contaminant migration. Any opportunity to relate cave patterns to the nature of their host aquifers will assist in these applied studies as well. Osborne (Chapter 3.7) examines the significance of paleokarst in speleogenesis. More specific issues are treated by Klimchouk (The nature of epikarst and its role in vadose speleogenesis, Chapter 3.5) and by V.Dublyansky and Y.Dublyansky (The role of condensation processes, Chapter 3.6). Part 4 outlines the fundamental physics and chemistry of the speleogenetic processes (Chapter 4.1) and presents a variety of different approaches to modeling cave conduit development (Chapter 4.2). In Chapter 4.1, the chemical reactions during the dissolution of the common soluble minerals, calcite, gypsum, salt and quartz, are discussed with the basic physical and chemical mechanisms that determine their dissolution rates. As limestone is the most common karst rock and its dissolution is the most complex in many respects, it receives the greatest attention. Dreybrodt (Section 4.1.1) and Dreybrodt and Eisenlohr (Section 4.1.2) provide advanced discussion and report the most recent experimental data, which are used to obtain realistic dissolution rates for a variety of hydrogeologic conditions and as input for modeling the evolution of conduits. Although direct comparisons between theoretical or analytical dissolution rates and those derived from field measurements is difficult, a very useful comparison is provided by W.White (Section 4.1.3). The bulk removal of carbonate rock from karst drainage basins can be evaluated either by direct measurement of rock surface retreat or by mass balance within known drainage basins. All of these approaches make sense and give roughly accurate results that are consistent with theoretical expectations. It is well recognized today that the earliest, incipient, phases of speleogenesis are crucial in building up the pattern of conduits that evolve into explorable cave systems. It is difficult to establish the major controls on these initial stages by purely analytical or intuitive methods, so that modeling becomes particularly important. Various approaches are presented in Chapter 4.2. Ford, Ewers and Lauritzen present the results of systematic study of the propagation of conduits between input and output points in an anisotropic fissure, using a variety of hardware and software models, in series representing the "single input", "multiple inputs in one rank", and "multiple inputs in multiple ranks" cases (Section 4.2.1). The results indicate important details of the competitive development of proto-conduits and help to explain branching cave patterns. In the competition between inputs, some principal tubes in near ranks first link ("breakthrough") to an output boundary. This re-orients the flowfields of failed nearby competitors, which then extend to join the principal via their closest secondaries. The process extends outwards and to the rear, linking up all inputs in a "cascading system". The exploding growth of computer capability during the last two decades has greatly enhanced possibilities for digital modeling of early conduit development. Investigating the growth of a single conduit is a logical first step in understanding the evolution of caves, realized here by Dreybrodt and Gabrov?ek in the form of a simple mathematical model (Section 4.2.2) and by Palmer by numerical finite-difference modeling (Section 4.2.3). The models show that positive feedback loops operate; widening a fracture causes increasing flow through it, therefore dissolution rates increase along it and so on, until finally a dramatic increase of flow rates permits a dramatic enhancement of the widening. This breakthrough event terminates the initial stage of conduit evolution. From then on the water is able to pass through the entire conduit while maintaining sufficient undersaturation to preserve low-order kinetics, so the growth rate is very rapid, at least from a geological standpoint -- usually about 0.001-0.1 cm/yr. The initiation ("breakthrough") time depends critically on the length and the initial width of the fracture and, for the majority of realistic cases, it covers a time range from a few thousand years to ten million years in limestones. The modeling results give a clear explanation of the operation of selectivity in cave genesis. In a typical unconfined karst aquifer there is a great range of enlargement rates along the competing flow routes, and only a few conduits will grow to enterable size. The modeling also provides one starting point (others are discussed in Chapter 5.2) to explain uniform maze patterns, which will be favored by enlargement of all openings at comparable rates where the discharge/length ratio is great enough. Single-conduit modeling has the virtue of revealing how the cave-forming variables relate to each other in the simplest possible way. Although it is more difficult to extend this approach to two dimensions, many have done so (e.g. Groves & Howard, 1994; Howard & Groves, 1995; in this volume ? Ford, Ewers and Lauritzen, Section 4.2.1; Dreybrodt and Siemers, Section 4.2.4, and Sauter and Liedl, Section 4.2.5). The modeling performed by Dreybrodt and Siemers shows that the main principles of breakthrough derived from one-dimensional models remain valid. The evolution of karst aquifers has been modeled for a variety of different geological settings, including also variation in lithology with respect to the dissolution kinetics. Sauter and Liedl simulate the development of conduits at a catchment scale for fissured carbonate rocks with rather large initial openings (about 1 mm). The approach is based upon hydraulic coupling of a pipe network to matrix continuum in order to represent the well-known duality of karst aquifer flow systems. It is also shown how understanding of the genesis of karst aquifers and modeling of their development can assist in characterization of the conduit system, which dominates flow and transport in karst aquifers. An important point that has emerged from cave studies of the last three decades is that no single speleogenetic model applies to all geologic and hydrologic settings. Given that settings may also change systematically during the evolutionary geological cycles outlined above (Chapter 3.1), an evolutionary approach is called for. This is attempted in Part 5, which is organized to give extended accounts of speleogenesis in the three most important settings that we recognize: coastal and oceanic (Chapter 5.1), deep-seated and confined (Chapter 5.2) and unconfined (Chapter 5.3). Each Chapter begins with a review of modern ideas on cave development in the setting, followed by representative case studies. The latter include new accounts of some "classic" caves as well as descriptions of other, little-known cave systems and areas. Readers may determine for themselves how well the real field examples fit the general models presented in the introductory sections. Mylroie and Carew in Chapter 5.1 summarize specific features of cave and karst development in young rocks in coastal and island settings that result from the chemical interactions between fresh and salt waters, and the effects of fluctuating sea level during the Quaternary. The case studies include a review of syngenetic karst in coastal dune limestones, Australia (S.White, 5.1.1) and an example of speleogenesis on tectonically active carbonate islands (Gunn and Lowe, 5.1.2). Klimchouk in Chapter 5.2 reviews conditions and mechanisms of speleogenesis in deep-seated and confined settings, one of the most controversial but exciting topics in modern cave research. Conventional karst/speleogenetic theories are concerned chiefly with shallow, unconfined geologic settings, supposing that the karstification found there is intimately related to surface conditions of input and output, with the dissolution being driven by downward meteoric water recharge. The possibility of hypogenic karstification in deeper environments has been neglected for a long time, and the quite numerous instances of karst features found at significant depths have usually been interpreted as buried paleokarst. However, the last decade has seen a growing recognition of the variety and importance of hypogene dissolution processes and of speleogenesis under confined settings which often precedes unconfined development (Hill, 1987, 1995; Klimchouk, 1994, 1996, 1997; Lowe, 1992; Lowe & Gunn, 1995; Mazzullo & Harris, 1991, 1992; Palmer, 1991, 1995; Smart & Whitaker, 1991; Worthington, 1991, 1994; Worthington & Ford, 1995). Confined (artesian) settings were commonly ignored as sites for cave origin because the classic concept of artesian flow implies long lateral travel distances for groundwater within a soluble unit, resulting in a low capacity to generate caves in the confined area. However, the recognition of non-classical features in artesian flow, namely the occurrence of cross-formation hydraulic communication within artesian basins, the concepts of transverse speleogenesis and of the inversion of hydrogeologic function of beds in a sequence, allows for a revision of the theory of artesian speleogenesis and of views on the origin of many caves. It is proposed that artesian speleogenesis is immensely important to speleo-inception and also accounts for the development of some of the largest known caves in the world. Typical conditions of recharge, the flow pattern through the soluble rocks, and groundwater aggressiveness favor uniform, rather than competing, development of conduits, resulting in maze caves where the structural prerequisites exist. Cross-formational flow favors a variety of dissolution mechanisms that commonly involve mixing. Hydrogeochemical mechanisms of speleogenesis are particularly diverse and potent where carbonate and sulfate beds alternate and within or adjacent to hydrocarbon-bearing sedimentary basins. Hypogene speleogenesis occurs in rocks of varied lithology and can involve a variety of dissolution mechanisms that operate under different physical constraints but create similar cave features. Case studies include the great gypsum mazes of the Western Ukraine (Klimchouk, Section 5.2.1), great maze caves in limestones in Black Hills, South Dakota (Palmer, Section 5.2.2) and Siberia (Filippov, Section 5.2.3), karstification in the Redwall aquifer, Arizona (Huntoon, Section 5.2.4), hydrothermal caves in Hungary (Y.Dublyansky, Section 5.2.6), and sulfuric acid speleogenesis (Lowe, Bottrell and Gunn, Section 5.2.7, and Hill, Section 5.2.8). Y.Dublyansky summarizes the peculiar features of hydrothermal speleogenesis (Section 5.2.5), and V.Dublyansky describes an outstanding example of a hydrothermal cavity, in fact the largest ever recorded by volume, in the Rhodope Mountains (Section 5.2.9). Recognition of the scale and importance of deep-seated speleogenesis and of the hydraulic continuity and cross-formational communications between aquifers in artesian basins is indispensable for the correct interpretation of evolution of karst aquifers, speleogenetic processes and associated phenomena, regional karst water-resource evaluations, and the genesis of certain karst-related mineral deposits. These and other theoretical and practical implications still have to be developed and evaluated, which offers a wide field for further research efforts. Ford in Chapter 5.3 reviews theory of speleogenesis that occurs where normal meteoric waters sink underground through the epikarst or dolines and stream sinks, etc. and circulate in the limestone or other soluble rocks without any major artesian confinement. These are termed common caves (Ford & Williams, 1989) because they probably account for 90% or more of the explored and mapped dissolutional caves that are longer than a few hundred meters. This estimate reflects the bias in exploration; caves formed in unconfined settings and genetically related to surface recharge are the most readily accessible and hence form the bulk of documented caves. Common caves display chiefly the branchwork forms where the dissolutional conduits occupy only a tiny proportion of the total length or area of penetrable fissures that is available to the groundwaters. The rules that govern the selection of the successful linkages that will be enlarged into the branchwork pattern are supported in the models presented in Chapter 4.2. In the long section caves may be divided into deep phreatic, multi-loop, mixed loop and water table, and ideal water table types, with drawdown vadose caves or invasion vadose caves above them. Many large systems display a mixture of the types. The concepts of plan pattern construction, phreatic, water table or vadose state, and multi-phase development of common caves are illustrated in the case studies that follow the introduction. They are organized broadly to begin with examples of comparatively simple deep phreatic and multi-loop systems (El Abra, Mexico, Ford, Section 5.3.1 and Castleguard Cave, Canada, Ford, Lauritzen and Worthington, Section 5.3.2), proceeding to large and complex multi-phase systems such as the North of Thun System, Switzerland (Jeannin, Bitterly and Hauselmann, Section 5.3.3) and Mammoth Cave, Kentucky (Palmer, Section 5.3.8), to representatives of mixed vadose and phreatic development in mountainous regions (the Alps, Audra, Section 5.3.4; the Pyrenees, Fernandez, Calaforra and Rossi, Section 5.3.5; Mexico, Hose, Section 5.3.6) and where there is strong lithologic or structural control (Folded Appalachians, W.White, Section 5.3.7; gypsum caves in the South of Spain, Calaforra and Pulido-Bosch, Section 5.3.10). Two special topics are considered by W.White in Section 5.3.9 (Speleogenesis of vertical shafts in the eastern US) and Palmer (Maze origin by diffuse recharge through overlying formation). The set concludes with two instances of nearly ideal water table cave development (in Belize and Hungary, Ford, Section 5.3.12), and a review of the latest models of speleogenesis from the region where modern karst studies in the West began, the Classical Karst of Slovenia and Trieste (?u?ter?ic, Section 5.3.13). In Parts 2-5 attention is directed primarily on how the gross geometry of a cave system is established. Part 6 switches focus to the forms at meso- and micro- scales, which can be created during enlargement of the cave. Lauritzen and Lundberg in Chapter 6.1 summarize the great variety of erosional forms ( speleogenetic facies ) that can be created by a wide range of speleogenetic agents operating in the phreatic or vadose zones. Some forms of cave passages have been subject to intensive research and may be interpreted by means of simple physical and chemical principles, but many others are polygenetic and hence difficult to decipher with certainty. However, in addition to the analysis of cave patterns (see Chapter 3.4), each morphological element is a potential tool that can aid our inferences on the origin of caves and on major characteristics of respective past hydrogeological settings. In Chapter 6.2 E.White and W.White review breakdown morphology in caves, generalizing that the processes are most active during the enlargement and decay phases of cave development. Early in the process breakdown occurs when the flow regime shifts from pipe-full conditions to open channel conditions (i.e. when the roof first loses buoyant support) and later in the process breakdown becomes part of the overall degradation of the karst system. The chapter addresses the mechanism of breakdown formation, the geological triggers that initiate breakdown, and the role that breakdown plays in the development of caves. As the great majority of both theoretical considerations and case studies in this book deal with speleogenesis in carbonate rocks, it is useful to provide a special forum to examine dissolution cave genesis in other rocks. This is the goal of Part 7. Klimchouk (7.1) provides a review of speleogenesis in gypsum. This appears to be a useful playground for testing the validity and limitations of certain general speleogenetic concepts. Differences in solution kinetics between gypsum and calcite impose some limitations and peculiar features on the early evolution of conduits in gypsum. These peculiarities appear to be an extreme and more obvious illustration of some rules of speleogenetic development devised from conceptual and digital modeling of early conduit growth in limestones. For instance, it is shown (e.g. Palmer, 1984, 1991; Dreybrodt, 1996; see also Chapter 3.4 and Section 4.2.2) that initiation of early, narrow and long pathways does not seem feasible under linear dissolution rate laws (n=1) due to exponential decrease of the dissolution rates. Although the dissolution kinetics of gypsum are not well known close to equilibrium it is generally assumed that they are controlled entirely by diffusion and therefore linear. If dissolution of gypsum is solely diffusion-controlled, with no change in the kinetic order, conduit initiation could not occur in phreatic settings or by lateral flow through gypsum from distant recharge areas in artesian settings. Hence, the fact that maze caves are common in gypsum in artesian conditions (see Section 5.2.1) gives strong support to a general model of "transverse" artesian speleogenesis where gypsum beds are underlain by, or sandwiched between, insoluble or low-solubility aquifers (Chapter 5.2), and suggests that it may be applicable to cave development in carbonates. In unconfined settings, speleogenesis in gypsum occurs along fissures wide enough to support undersaturated flow throughout their length. Linear or crudely branching caves overwhelmingly predominate, which rapidly adjust to the contemporary geomorphic setting and to the maximum available recharge. Also, if considerable conduit porosity has been created in deep-seated settings, it provides ready paths for more intense groundwater circulation and further cave development when uplift brings the gypsum into the shallow subsurface. Speleogenesis in salt, reviewed in general and exemplified by the Monte Sedom case in Israel (Frumkin, Chapter 7.2), has been documented only in open, unconfined settings, where it provides a model for simple vadose cave development. Chapter 7.3 deals with speleogenesis in quartzites, illustrated by case studies from southeastern Minas Gerais, Brasil (Correa Neto, 7.3.1) and South Africa (Martini, 7.3.2). The process involves initial chemical weathering of the quartzite to create zones of friable rocks (sanding, or arenisation) which then are removed by piping, with further conduit enlargement due to mechanical erosion by flowing water. Part 8 combines the theoretical with some applied aspects of speleogenetic studies. Worthington, Ford and Beddows (8.1) show the important implications of what might be termed "speleogenetic wisdom" when studying ground water behaviour in karst. They examine some standard hydrogeological concepts in the light of knowledge of caves and their patterns, considering a range of case studies to identify the characteristic enhancement of porosity and permeability due to speleogenesis that occurs in carbonate rocks. The chapter focuses on unconfined carbonate aquifers as these are the most studied from the speleological perspective and most important for water supplies. Four aquifers, differing in rock type, recharge type (allogenic and autogenic), and age (Paleozoic, Mesozoic and Cenozoic), are described in detail to demonstrate the extent of dissolutional enhancement of porosity and permeability. It is shown that all four cases are similar in hydraulic function, despite the fact that some of them were previously characterized as different end members of a "karst ? non-karst" spectrum. Enhancement of porosity by dissolution is relatively minor: enhancement of permeability is considerable because dissolution has created dendritic networks of channels able to convey 94% or more of all flow in the aquifer, with fractures providing a small proportion and the matrix a negligible amount. These conclusions may be viewed as a warning to hydrogeologists working in carbonate terranes: probably the majority of unconfined aquifers function in a similar manner. Sampling is a major problem in their analysis because boreholes (the conventional exploration tool in hydrogeology) are unlikely to intersect the major channels that are conveying most of the flow and any contaminants in it. It is estimated, using examples of comprehensively mapped caves, that the probability of a borehole intersecting a conduit ranges from 1 in 50 to 1 in 1000 or more. Boreholes simply cannot be relied upon to detect the presence of caves or to ?characterise? the hydrologic functioning of cavernous aquifers. Wherever comprehensive evidence has been collected in unconfined carbonate aquifers (cave mapping plus boreholes plus lab analysis of core samples) it suggests that dissolution inexorably results in a similar structure, with channel networks providing most of the permeability of the aquifer, yet occupying a very minor fraction of its volume (Worthington, Ford and Beddows). Lowe (Chapter 8.2) focuses on developments in understanding the vital role played by karstic porosity, (broadly viewed as being the product of speleogenesis), in the migration of mineralizing fluids (or hydrocarbons) and in their deposition (or storage), and comments on the potential role of new speleogenetic concepts in developing greater understanding in the future. Although some early workers were clearly aware of actual evidence for some kind of relationship, and others noted its theoretical likelihood, it has been ignored by many until relatively recent times. This shortfall has gradually been redressed; new understanding of the extent and variety of karst processes is ensuring that new relationships are being recognized and new interpretations and models are being derived. The chapter does not pretend to give a comprehensive account of the topic but clearly demonstrates the wide applicability of speleogenetic knowledge to issues in economic geology. In Chapter 8.3 Aley provides an overview of the water and land-use problems that occur in areas with conduit aquifers. He stresses that sound land management must be premised on an understanding that karst is a three-dimensional landscape where the surface and subsurface are intimately and integrally connected. Failure to recognize that activity at the surface affects the subsurface, and the converse, has long been the root cause of many of the problems of water and land use in karst regions. Karst areas have unique natural resource problems, whose management can have major economic consequences. Although there is an extensive literature on the nature of particular problems, resource protection and hazard minimization strategies in karst, it rarely displays an advanced understanding of the processes of the conduit formation and their characteristics yet these will always be involved. This book does not pretend to be a definitive text on speleogenesis. However, it is hoped that readers will find it to be a valuable reference source, that it will stimulate new ideas and approaches to develop and resolve some of the remaining problems, and that it will promote an appreciation of the importance of speleogenetic studies in karst hydrogeology and applied environmental sciences. Acknowledgements: We sincerely thank all contributors for their willing cooperation in the long and difficult process of preparing this book, for their participation in developing its logic and methodology and their cheerful response to numerous requests. We thank all colleagues who discussed the work with us and encouraged it in many ways, even though not contributing to its content as authors. We are particularly grateful to Margaret Palmer for invaluable help in editing the English in many contributions, to Nataly Yablokova for her help in performing many technical tasks and to Elizabeth White who prepared comprehensive index. Our thanks are due to Dr. David Drew, Dr. Philip LaMoreaux, Dr. George Moore and Prof. Marian Pulina for reviewing the manuscript and producing constructive notes and comments on improvement of the final product. The organizational costs and correspondence related to the preparation of the book were partially sponsored by the National Speleological Society, the publisher. We thank David McClurg, the Chair of the NSS Special Publication Committee, for his extensive technical and organizational support in the preparation and publishing processes.

Remote Sensing and GIS-Based Analysis of Cave Development in the Suoimuoi Catchment (Son La - NW Vietnam), 2002, Hung, L. Q. , Dinh, N. Q. , Batelaan, O. , Tam, V. T. , Lagrou, D.
Integration of remotely sensed imagery with ground surveys is a promising method in cave development studies. In this research a methodology was set up in which a variety of remote sensing and GIS techniques support cave analysis in the tropical karst area of the Suoimuoi catchment, NW Vietnam. In order to extract the maximum information from different remotely sensed data, the hue invariant IHS transformation was applied to integrate Landsat multispectral channels with the high resolution Landsat 7 ETM panchromatic channel. The resulting fused image was used, after enhancement, to visually and digitally extract lineaments. Aerial photos evaluated the extracted lineaments. Based on lineament density indices a fracture zone favorable for cave development is defined. The distance between caves and faults was investigated as well as the correspondence between the cave occurrence and the fracture zone.

Public Datasets Integrated with GIS and 3-D Visualization Help Expand Subsurface Conceptual Model, 2002, Phelan, T. L.
Public domain water well drilling logs were used to construct a 3-D visualization of the subsurface in a karst terrain. Subsurface displacements seen in the 3-D visualization model were shown to correlate with surface topography in the Digital Elevation Model (DEM). This methodology could improve the effectiveness of limited funding by using public datasets to contribute to conceptual hydrogeologic models. It could also identify areas that merit additional investigation which might have gone unnoticed otherwise

Geohazard map of cover-collapse sinkholes in the 'Tournaisis' area, southern Belgium, 2002, Kaufmann O. , Quinif Y. ,
This paper reports the methodology developed to draw up a geohazard map of cover-collapse sinkhole occurrences in the 'Toumaisis' area. In this area, Carboniferous limestones are overlain by a Mesocenozoic cover, mainly consisting of marls, sand and clay. The thickness of this cover ranges from a few meters to more than 100 m. The surficial morphology of the area does not show any karstic evidence except for the occurrence of these collapses. From a paleogeographical point of view, a developed quaternary karst is not conceivable in the area. Recent works suggested that the collapses are set off from reactivated paleokarsts. The paleokarsts studied in the area proved to be the result of a particular weathering of the limestone. The organization of these paleokarsts seems very low and mainly guided by the limestone fracturing. As for most induced sinkholes, the reactivation of these paleokarsts is linked to the lowering of piezometric heads. In most of the area, a thick cover and intensive land use mask potential surface hints of the buried paleokarsts and of the fracturing of the bedrock. Aerial photographs and remote sensing techniques have therefore shown little results in delineating collapse hazard zones up to now. The study of the surficial morphology is also of little help. In order to draw up the geohazard map in such a difficult context, hydrogeological data and geological mapping information could only be used. These informations are based on a limited number of boreholes and piezometers and are thus, only valid on a regional scale. Records of former collapses were also available. These records were of great interest since sinkhole distribution is obviously clustered in the area. Bedrock roof and cover formation floor altitudes were digitized and adapted to produce digital thematic maps. Piezometric heads were imported from a calibrated groundwater model of the aquifer. These data and a digital elevation model of the area were integrated into a geographical information system (GIs) to produce a coherent 3-D description of the area on a regional scale. Parameters such as the dewatering of the limestone and the thickness of the cover formation where sinkholes occurred were then estimated. Density of former collapses was also computed. This showed that zones of high sinkhole occurrence coincide with zones of heavy lowering of piezometric heads. Combining the density of former collapses with the dewatering of the limestone enabled us to delineate zones of low, moderate and high collapse hazard. (C) 2002 Elsevier Science B.V. All rights reserved

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