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Enviroscan Ukrainian Institute of Speleology and Karstology


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Community news

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 gravitational head is the component of total hydraulic head related to the position of a given mass of water relative to an arbitrary datum [22].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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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 stress (Keyword) returned 119 results for the whole karstbase:
Showing 31 to 45 of 119
Hydrochemical approach to the alterations of the recharge of a karst aquifer consecutive to a long pumping period: Example taken from Pinchinade graben (Mouans-Sartoux, French Riviera), 1999,
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Reynaud A. , Guglielmi Y. , Mudry J. , Mangan C. ,
The carbonate aquifer of the Pinchinade graben, which has a well-delimited geometry, involves water,vith well-defined chemical types from calcium sulfate to magnesium bicarbonate. Each ground water type corresponds to a well-delimited area of the aquifer: the magnesium bicarbonate for the Liassic and Rhetian limestone water (with 10 to 30 mg L-1 of sulfate) and calcium sulfate for the water of the relatively impermeable layer of the underlying Keuper (with 300 to 1500 mg L-1 of sulfate). A four-year pumping test,vith a bimonthly to daily monitoring of water chemistry has allowed evaluation of the renewal of the exploitable water reserve. During the four-year period, the survey shows that the average discharge is balanced by natural recharge (2.8 to 105 m(3) y(-1)). A change in the chemical character of the water was observed from Rhetian to Keuper type (from 35 to 167 mg L-1 of sulfate), Such a change indicates a progressive exhaustion of the Rhetian reserves, which are the greater part of the exploitable reserve in the area. The same phenomenon is observed daily depending on the pumped discharge and the season. For pumping rates below 26 m(3) h(-1), the borehole drains the Rehetian inflows to a degree depending on high or low water levels. For pumping rates above 26 m(3) h(-1), whatever the period, the permeable Keuper layers are pumped and sulfate peaks ensue

Cave diving explorations in the spring of Rjecina., 1999,
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Kuhta M.
The spring of Rjecina is one of the biggest springs in the area of Dinaric Karst. It is situated approximately 10 km in the North from the town of Rijeka. As a part of the last hydrogeological explorations cave diving team of SK from Zagreb performed the cave diving investigation of the water covered cave canals of the spring. The total length of the spring karstic system has been increased on 260 m with final reached point on depth of 50.5 m. Based on the results of cave diving exploration as well as on analysis of all the former investigations the major conclusions can be made. First of all, upper and lower inlet canals of the spring are hydraulically quite separated. Further, it can be supposed that in the background, they are in continuation of the separated retention areas. In the dry period both underground canals have no direct connection with the retention areas and the water present in the spring is only the rest of the last flowing out "captured" in the underground caves. It means that the possibilities of obtaining considerable quantities of the groundwater in the spring itself (in the dry period) by overpumping, i.e. by considerably lowering the water level in spring, are very small and the investigations should be directed towards another solutions. Although the mentioned conclusions are based on the data obtained at complete hydrogeological processing, it is important to stress the considerable contribution of the speleologic and cave diving investigations. It has been proved that these investigations are very important in karst areas. With undoubtedly important information concerning morphology of underground, which is the supposition for planning and performing the investigation works and other operations, speleologic and cave diving observations con contribute better understanding of the complex hydrogeological relations.

Sources et hydrosystmes karstiques des rgions arides et semi-arides, essai gographique, 2000,
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Nicod, Jean
SPRINGS AND KARSTIC HYDROSYSTEMS IN THE ARID AND SEMI-ARID AREAS. A GEOGRAPHICAL ESSAY - The patterns of the main springs and hydrosystems in the deserts and surroundings are sorted, according to their geomorphological situation (piedmont, coastal or inner plateau), to structure of the aquifers and working of groundwater (storage capacity, artesian systems) and to the hydrochemical criteria particularly the solute load in Mg2+, SO42- and Cl-. From the best known examples, the main problems on the genesis and working of the karstic hydro-systems in arid environment are discussed: - the incidence of tectonic stress and paleokarstic and paleoclimatic inheritances; - the recent periods of recharge (in Northern Sahara and Near and Middle East); - the interactions in ionic solutions and hyper-karstic processes: particular_ly with the strong acid, H2SO4, the "double solvency effect", and the mixing water corrosion near the salt water wedge in the coastal karsts.

Climate-change impacts in a regional karst aquifer, Texas, USA, 2000,
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Loaiciga H. A. , Maidment D. R. , Valdes J. B. ,
Climate-change scenarios were created from scaling factors derived from several general circulation models to assess the likely impacts of aquifer pumping on the water resources of the Edwards Balcones Fault Zone (BFZ) aquifer, Texas, one of the largest aquifer systems in the United States. Historical climatic time series in periods of extreme water shortage (1947-1959), near-average recharge (1978-1989), and above-average recharge (1975-1990) were scaled to 2 x CO2 conditions to create aquifer recharge scenarios in a wanner climate. Several pumping scenarios were combined with 2 x CO2 climate scenarios to assess the sensitivity of water resources impacts to human-induced stresses on the Edwards BFZ aquifer. The 2 x CO2 climate change scenarios were linked to surface hydrology and used to drive aquifer dynamics with alternative numerical simulation models calibrated to the Edwards BFZ aquifer, Aquifer simulations indicate that, given the predicted growth and water demand in the Edwards BFZ aquifer region, the aquifer's ground water resources appear threatened under 2 x CO2 climate scenarios. Our simulations indicate that 2 x CO2 climatic conditions could exacerbate negative impacts and water shortages in the Edwards BFZ aquifer even if pumping does not increase above its present average level. The historical evidence and the results of this article indicate that without proper consideration to variations in aquifer recharge and sound pumping strategies, the water resources of the Edwards BFZ aquifer could be severely impacted under a warmer climate. (C) 2000 Elsevier Science B.V. All rights reserved

Ecological incidents in Northern Adriatic Karst (Croatia), 2000,
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Geres D, Rubinic J, Ozanic N,
In spite of growing efforts to preserve the quality of groundwater resources, accidental pollution is becoming increasingly frequent, resulting in long-lasting impact on the groundwater status. The consequences of ecological accidents are particularly expressed in karst regions, which are caused by the geological properties of the area where the groundwater aquifers are situated, as well as by hydrological circumstances which also influence the dynamic mechanisms of water flow and transportation of pollution in the karst environment. The paper stresses the hydrological component of karst aquifer function and the related role of hydrology in assessment of the hazards caused by accidental pollution and, once the accident has happened, in monitoring the situation and forecasting the possible impact on water resources. The analysis of ecological accidents in the karst has been made, based on the actual examples of accidents involving fuel substances recorded in the Northern Adriatic karst area in Croatia in the period from 1990 to 1998. The basic characteristics of the mechanism of water movement in the karst are presented from the hydrological standpoint, as well as the related risk of rapid transportation of pollutants into the parts of the aquifers used for water supply. The paper also contains proposals for possible approaches to protection of particularly valuable water resources in the karat from accidental pollution occurring in road transport

Speleogenesis: Evolution of Karst Aquifers., 2000,
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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.

Karst collapse mechanism and criterion for its stability, 2001,
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He K. Q. , Liu C. L. , Wang S. J. ,
Karst collapse, caused by natural or artificial abstraction of groundwater, has been a focus of environmental geological problems for its ever-increasing hazardousness. The potential erosion theory and vacuum suction erosion theory, which reveal the origin of karst collapse macroscopically, are popularly accepted. However, a mathematic prediction criterion for karst collapse cannot be established only by these two theories. From a new perspective, this paper attempts to explain the microcosmic mechanism of karst collapse on the basis of these two theories. When the shear stress surpasses the shear strength of soil, a certain point or a certain plane in the unconsolidated soil covering karst caves will fail under the mechanical effects of water and air as well as its load-pressure, and with the increase of damaged points, a breaking plane appears and the soil on karst caves is completely damaged; as a result, the karst ground collapses. On the basis of the Mohr-Coulomb failure theory and previous studies, the paper presents a prediction criterion of karst collapse. Finally, by taking, for example, nine typical cases of collapse caused by pumping tests in Guizhou, the paper gives the calculation process of the model and proves its reliability

Quaternary tectonics: Influence on the structure of two karstic aquifers of Languedoc (France), 2001,
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Josnin J. Y. ,
Our research focuses on the effect of Quaternary tectonics on the organization of the conduit network of karst ground water flow. In the Languedoc region, the major karstic systems are developed in Malm and Lower Cretaceous platform limestones. Most of these systems are polygenetic, their genesis and evolution having been controlled by fracturing that occurred during major tectonic phases (ante-Senonian, Eocene, Oligocene, Aquitanian, Pliocene). These complex karst systems were reactivated following Messinian eustatic events, under tectonic conditions which are not well-known, particularly those that occurred during the Quaternary. Small scale deformations and a lack of seismic activity make characterization of current tectonics in Mediterranean Languedoc difficult. The presence of vertical offsets, however, demonstrates that there are active faults in the interior of or in proximity to karst systems. In two karst aquifers within the Garden basin, we have observed a correlation between the orientations of active faults and the principal karst conduits. In the Mialet basin, we demonstrate that erosion resulting from post-Miocene uplift (and so changes of boundary conditions) divides the aquifer into smaller, independent units. In the St Chaptes basin, we reconstruct the history of the karst, proposing that tectonic and eustatic events were predominant in the karstification process and that the climatic conditions were only of secondary importance. We also show how the reactivation of faults can lead to the unblocking of abandoned karst conduits, allowing their reintroduction into the active flow system, a phenomenon that can be explained by the combined influence of the present stress field and hydraulic gradients. This work, which represents a preliminary study, leads to hypotheses that we will subsequently validate through different successive modelings

Chemical and physical controls on waters discharged from abandoned underground coal mines, 2001,
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Lopez D. L. , Stoertz M. W. ,
Abandoned up-dip drift mines in high-sulphur coal are a major source of acid mine drainage (AMD) in Appalachia. Studies of mines in the Monday Creek watershed of southeastern Ohio show that mines are recharged by surface runoff into subsidence features that dilate the natural stress-relief fracture system. The direct connection between the ground surface and the mines leads to a rapid response in the hydrograph, with a one- to four-day lag between precipitation and corresponding peak mine discharge. Subsidence occurs in topographic depressions where overburden is presumably relatively thin. Subsidence features drain 20-36% of the surface area. Unsaturated storage appears to be volumetrically insignificant, so that far more recharge occurs than the 5% often assumed for this region. Mine storage can change rapidly due to subsidence recharge. Hydrologically, mines with subsidence features behave like karst systems, with meteoric quickflow' representing more than 50% of the total flow. Mine discharge concentrations are relatively uniform through time, suggesting either equilibrium controls on chemistry or drainage of a well-mixed pool, or both. Evidence of dilution by high flows is slight. The first high flows after a baseflow period show only a slight increase in concentrations, attributed to flushing of stored reaction products. Loadings (concentrations x flow) depend on volumetric discharge and as a consequence are highly variable. The Eh/pH environment in up-dip drift mines indicates that mine waters are in contact with the atmosphere at least part of the time, unlike a true groundwater. Iron buffering partly controls pH, which clusters around values of 3.6-5.0

Modelling of speleothems failure in the Hotton cave (Belgium). Is the failure earthquake induced?, 2001,
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Cadorin Jf, Jongmans D, Plumier A, Camelbeeck T, Delaby S, Quinif Y,
To provide quantitative information on the ground acceleration necessary to break speleothems, laboratory measurements on samples of stalagmite have been performed to study their failure in bending. Due to their high natural frequencies, speleothems can be considered as rigid bodies to seismic strong ground motion. Using this simple hypothesis and the determined mechanical properties (a minimum value of 0.4 MPa for the tensile failure stress has been considered), modelling indicates that horizontal acceleration ranging from 0.3 m/s(2) to 100 m/s(2) (0.03 to 10g) are necessary to break 35 broken speleothems of the Hotton cave for which the geometrical parameters have been determined. Thus, at the present time, a strong discrepancy exists between the peak accelerations observed during earthquakes and most of the calculated values necessary to break speleothems. One of the future research efforts will be to understand the reasons of the defined behaviour. It appears fundamental to perform measurements on in situ speleothems

Recent active faults in Belgian Ardenne revealed in Rochefort Karstic network (Namur Province, Belgium), 2001,
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Vandycke S. , Quinif Y. ,
This paper presents observations of recent faulting activity in the karstic network of the Rochefort Cave (Namur Province, Belgium, Europe). The principal recent tectonic features are bedding planes reactivated as normal faults, neo-formatted normal faults in calcite flowstone, fresh scaling, extensional features, fallen blocks and displacement of karstic tube. The seismotectonic aspect is expanded by the presence of fallen blocks where normally the cavity must be very stable and in equilibrium. Three main N 070degrees fault planes and a minor one affect, at a decimetre scale, the karst features and morphology. The faults are still active because recent fresh scaling and fallen blocks are observable. The breaking of Holocene soda straw stalactites and displacements of artificial features observed since the beginning of the tourist activity, in the last century, also suggest very recent reactivation of these faults. This recent faulting can be correlated to present-day tectonic activity, already evidenced by earthquakes in the neighbouring area. Therefore, karstic caves are favourable sites for the observation and the quantification of recent tectonic activity because they constitute a 3-D framework, protected from erosion. Fault planes with this recent faulting present slickensides. Thus a quantitative analysis in term of stress inversion, with the help of striated faults, has permitted to reconstruct the stress tensor responsible for the brittle deformation. The principal NW-SE extension (sigma(3) horizontal) is nearly perpendicular to that of the present regional stress as illustrated by the analysis of the last strong regional earthquake (Roermond, The Netherlands) in 1992. During the Meso-Cenozoic, the main stress tectonics recorded in this part of the European platform is similar to the present one with a NE-SW direction of extension. The discrepancy between the regional stress field and the local stress in the Rochefort cave can be the result of the inversion of the sigma(2) and sigma(3) axes of the stress ellipsoid due to its symmetry or of a local modification at the ground surface of the crustal stress field as it has been already observed in active zones

The scapulocoracoid of an early triassic stem-frog from Poland, 2002,
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Borsukbialynicka M, Evans Se,
The scapulocoracoid of Czatkobatrachus polonicus Evans and Borsuk-Bialynicka, 1998, a stem-frog from the Early Triassic karst locality of Czatkowice (Southern Poland), is described. The overall type of scapulocoracoid is plesiomorphic, but the subcircular shape and laterally oriented glenoid is considered synapomorphic of Salientia. The supraglenoid foramen is considered homologous to the scapular cleft of the Anura. In Czatkobatrachus, the supraglenoid foramen occupies an intermediate position between that of the early tetrapod foramen and the scapular cleft of Anura. The cleft scapula is probably synapomorphic for the Anura. In early salientian phylogeny, the shift in position of the supraglenoid foramen may have been associated with an anterior rotation of the forelimb. This change in position of the forelimb may reflect an evolutionary shift from a mainly locomotory function to static functions (support, balance, eventually shock-absorption). Laterally extended limbs may have been more effective than posterolateral ones in absorbing landing stresses, until the specialised shock-absorption pectoral mechanism of crown-group Anura had developed. The glenoid shape and position, and the slender scapular blade, of Czatkobatrachus, in combination with the well-ossified joint surfaces on the humerus and ulna, all support a primarily terrestrial rather than aquatic mode of life. The new Polish material also permits clarification of the pectoral anatomy of the contemporaneous Madagascan genus Triadobatrachus

Role of an extension of pre-Quaternary age for the evolution of the carbonate massifs in the occidental Betic Cordillera: The case of the Yunquera-Nieves massif (southern Spain), 2002,
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Pistre Severin, Linan Cristina, Andreo Bartolome, Carrasco Francisco, Drogue Claude, Martinalgarra Agustin,
A simultaneous analysis of the fracture geometry and paleo-stress fields of the karstic Yunquera-Nieves massif i n southern Spain (Malaga Province) has been carried out with microtectonic stations. It reveals polyphased t ec -tonics linked to the structural position of this carbonate domain in the western Betic Cordillera. Among the tectonic regimes described in this domain appears a distensive stage with a radial trend probably of post-Tortonian to Quaternary age. Todate, it has seldom been described and is absent from geodynamic models though it seems to have had a regional importance. Furthermore, it played a major role for the acquisition of the hydrodynamic properties of t he aquifer and its karstogenesis. This stage opened all fractures and allowed t he development of karstic drains with NW-SE and N-S directions. Finally, the karstic network was shaped by more recent climatic and tectonic events

Geological and geotechnical context of cover collapse and subsidence in mid-continent US clay-mantled karst, 2002,
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Cooley T,
This paper presents a synthesis of geologic and geotechnical concepts to present a unified model of conditions controlling The development of cover-collapse sinkholes and associated ground subsidence. Appropriate engineering response to the hazards associated with collapse and subsidence requires a full understanding of the underlying mechanisms that produce such effects. The geotechnical characteristics of the overlying clay mantle and occurrence of the associated cover-collapse features are not random, but rather are directly tied to the underlying water flow routes and their development through time. The clay mantle and underlying epikarst are two components of a single system, each of the components influencing the other. This paper brings together these two aspects in terms of the author's personal experience and observations as a geologist, geotechnical engineer, hydrogeologist, and caver. A summary of the basic model follows. Much of the clay mantle and pinnacled upper surface of the epikarst form while surface drainage still prevails. At this stage, the karst underdrains are insufficiently developed to transport soils, although some subsidence into cutters occurs because of dissolutional rock removal. Soil arches and macropore flow routes associated with cutters have developed by this stage. As competent deep conduits extend into the area by headward linking, the cutters with the most favorable drains are linked to the conduits first and act as attractors for the development of a tributary, laterally integrated drainage system in the epikarst. Once the most efficient cutter drains become competent to transport soils, the depressed top-of-rock and ground surfaces characteristic of dolines develop. A given doline underdrain is likely to have multiple tributary drains from adjacent cutters, which vary in soil transport competence. Soil stiffness in the clay mantle over the limestone varies as a result of the pattern of stresses imposed as the underlying rock surface is lowered by dissolution and later as soil piping locally removes soils. In the absence of karst, these soils would have developed a laterally uniform, stiff to very stiff consistency. Where soil near the soil-bedrock interface is locally removed, however, the weight of the materials overlying this void is transferred to abutment zones on the pinnacles by soil arches. Local soil loading in the abutment areas of these arches would increase at least on the-order of 50% in the case of an isolated cavity. In some cases, multiple closely spaced cutters whose soil arches have narrow, laterally constrained abutment zones bearing on the intervening pinnacles may produce substantially higher soil abutment stresses. If the clays in the abutment zones do not fail, they would respond to this increase in stress by consolidating: stiffening and decreasing in volume. The cutters spanned by the soil arches accumulate raveled soils that are 'under-consolidated', the soft zones noted between pinnacles by Sowers. A simple integral of stresses analysis makes it obvious, however that no continuous soft zone exists. It is the transfer of load to the pinnacles through the stiffened abutment soils that allows these locally soft areas to exist. Soil stiffness profiles from borings substantiate this pattern. Cover-collapse features develop where soil transport through cutter drains is sufficient to remove the soils from beneath these arched areas. Two types of collapse have been observed: type I collapses have an upward-stoping open void whose rubble pile is removed by transport as fast as it is generated, producing a deep, steep-sided final collapses. In some cases, multiple voids in clusters can form with narrow abutments separating them. Large collapses may involve a progressive failure of several members of a cluster, including intervening pillars. Type 2 features are soil-filled voids limited in their rate of upward growth by the rate of soil removal, have little open void space, and migrate to the ground surface as a column of soft soils, finally producing a shallow depression. The type 2 features have geotechnical significance because of their effect on settlement under imposed loads. A single underdrain system may service both types of features, the behavior of particular voids being dependent on the relative efficiencies of their drains. This behavior can also change with time because backfilling of the underdrains with soil or flushing out of the soil filling can occur with changes in hydrologic or erosional regimes

Poroelastic analysis of cover-collapse sinkhole formation by piezometric surface drawdown, 2002,
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Tharp T. M. ,
Where the water table is above the soil-rock contact in karst regions, cover-collapse sinkholes in the soil and soft sediment above the rock commonly occur as a result of drawdown of the piezometric surface in the karst aquifer. Transient stresses and pore pressures around soil voids at the soil-rock contact can cause hydraulic fracturing of the soil near the wall of the void. After the first such fracture, successive sloughing of soil propagates the soil void rapidly to the surface, resulting in a cover-collapse sinkhole. Sinkhole formation by this mechanism should be strongly a function of rate and magnitude of piezometric surface drawdown, permeability and tensile strength of the soil, and the size, depth, and geometry of the initial soil void. Large soil voids and those with walls that are partly planar or of low curvature are most susceptible to hydraulic fracture and the resulting progression to sinkhole formation

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