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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. ...

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That triple point is a point at which the solid, liquid, and vapor phases are in equilibrium [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 epigenic (Keyword) returned 62 results for the whole karstbase:
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The initiation of hypogene caves in fractured limestone by rising thermal water: investigation of a parallel series of competing fractures, 1999, Dumont K. A. , Rajaram H. , Budd D. A.
Integrated cave systems can either form at or near the surface of the earth (epigenic) or at some depth below the earth's surface (hypogenic)For caves that form in fractured limestone, the two most common types of cave-system morphologies are branchwork and mazeworkBranchwork caves are composed of tributaries that coalesce in the downstream direction, similar to surface streamsMazework caves exhibit two or more sets of parallel passages intersecting in a grid-like patternThe majority of epigenic caves exhibit branchwork morphologies, which represent the dominance of individual flow pathsIn contrast, mazework caves develop when dissolution occurs along numerous flow pathsWhereas most epigenic caves are related to surficial meteoric flow systems, some mazework caves are thought to have formed in hypogene environments where rising thermal water cools in response to the geothermal gradientOur objective is to examine the fundamental cause for the difference in morphology between epigenic and thermal hypogenic cave systems using numerical modelsIn particular, we are examining the competition between different flow paths in fractured limestone undergoing dissolutional enlargementAs noted in previous numerical studies, epigenic systems are characterized by the dominance of a single flow path, which is consistent with the structure of epigenic cavesSo, in order to explain the structure of maze caves, one has to explain why no single flow path attains dominanceThe retrograde solubility of calcite coupled with heat transfer from the fluid to the rock is hypothesized to provide the mechanism by which dissolutional power is distributed among all competing flow pathsNumerical models of fluid flow, heat transfer, and calcite dissolution chemistry are integrated to develop a model of hypogene cave initiation in fractured limestoneFlow is assumed to occur in the presence of a spatially variable rock temperature field that is constant through timePreliminary numerical modeling results for a system of parallel fractures demonstrate the differences in the nature of competition between flow paths in epigenic (constant temperature) and hypogenic systems (flow in the presence of a negative thermal gradient)Differences in results using various kinetic models for calcite dissolution are also presentedThe role of aperture variation and distribution in a parallel set of fractures is also examined

Hypogene Speleogenesis: Hydrogeological and Morphogenetic Perspective., 2007, Klimchouk A. B.

This book provides an overview of the principal environments, main processes and manifestations of hypogenic speleogenesis, and refines the relevant conceptual framework. It consolidates the notion of hypogenic karst as one of the two major types of karst systems (the other being epigenetic karst). Karst is viewed in the context of regional groundwater flow systems, which provide the systematic transport and distribution mechanisms needed to produce and maintain the disequilibrium conditions necessary for speleogenesis. Hypogenic and epigenic karst systems are regularly associated with different types, patterns and segments of flow systems, characterized by distinct hydrokinetic, chemical and thermal conditions. Epigenic karst systems are predominantly local systems, and/or parts of recharge segments of intermediate and regional systems. Hypogenic karst is associated with discharge regimes of regional or intermediate flow systems.

Various styles of hypogenic caves that were previously considered unrelated, specific either to certain lithologies or chemical mechanisms are shown to share common hydrogeologic genetic backgrounds. In contrast to the currently predominant view of hypogenic speleogenesis as a specific geochemical phenomenon, the broad hydrogeological approach is adopted in this book. Hypogenic speleogenesis is defined with reference to the source of fluid recharge to the cave-forming zone, and type of flow system. It is shown that confined settings are the principal hydrogeologic environment for hypogenic speleogenesis. However, there is a general evolutionary trend for hypogenic karst systems to lose their confinement due to uplift and denudation and due to their own expansion. Confined hypogenic caves may experience substantial modification or be partially or largely overprinted under subsequent unconfined (vadose) stages, either by epigenic processes or continuing unconfined hypogenic processes, especially when H2S dissolution mechanisms are involved.

Hypogenic confined systems evolve to facilitate cross-formational hydraulic communication between common aquifers, or between laterally transmissive beds in heterogeneous soluble formations, across cave-forming zones. The latter originally represented low-permeability, separating units supporting vertical rather than lateral flow. Layered heterogeneity in permeability and breaches in connectivity between different fracture porosity structures across soluble formations are important controls over the spatial organization of evolving ascending hypogenic cave systems. Transverse hydraulic communication across lithological and porosity system boundaries, which commonly coincide with major contrasts in water chemistry, gas composition and temperature, is potent enough to drive various disequilibrium and reaction dissolution mechanisms. Hypogenic speleogenesis may operate in both carbonates and evaporites, but also in some clastic rocks with soluble cement. Its main characteristic is the lack of genetic relationship with groundwater recharge from the overlying or immediately adjacent surface. It may not be manifest at the surface at all, receiving some expression only during later stages of uplift and denudation. In many instances, hypogenic speleogenesis is largely climate- independent.

There is a specific hydrogeologic mechanism inherent in hypogenic transverse speleogenesis (restricted input/output) that suppresses the positive flow-dissolution feedback and speleogenetic competition in an initial flowpath network. This accounts for the development of more pervasive channeling and maze patterns in confined settings where appropriate structural prerequisites exist. As forced-flow regimes in confined settings are commonly sluggish, buoyancy dissolution driven by either solute or thermal density differences is important in hypogenic speleogenesis.

In identifying hypogenic caves, the primary criteria are morphological (patterns and meso-morphology) and hydrogeological (hydrostratigraphic position and recharge/flow pattern viewed from the perspective of the evolution of a regional groundwater flow system). Elementary patterns typical for hypogenic caves are network mazes, spongework mazes, irregular chambers and isolated passages or crude passage clusters. They often combine to form composite patterns and complex 3- D structures. Hypogenic caves are identified in various geological and tectonic settings, and in various lithologies. Despite these variations, resultant caves demonstrate a remarkable similarity in cave patterns and meso-morphology, which strongly suggests that the hydrogeologic settings were broadly identical in their formation. Presence of the characteristic morphologic suites of rising flow with buoyancy components is one of the most decisive criteria for identifying hypogenic speleogenesis, which is much more widespread than was previously presumed. Hypogenic caves include many of the largest, by integrated length and by volume, documented caves in the world.

The refined conceptual framework of hypogenic speleogenesis has broad implications in applied fields and promises to create a greater demand for karst and cave expertise by practicing hydrogeology, geological engineering, economic geology, and mineral resource industries. Any generalization of the hydrogeology of karst aquifers, as well as approaches to practical issues and resource prospecting in karst regions, should take into account the different nature and characteristics of hypogenic and epigenic karst systems. Hydraulic properties of karst aquifers, evolved in response to hypogenic speleogenesis, are characteristically different from epigenic karst aquifers. In hypogenic systems, cave porosity is roughly an order of magnitude greater, and areal coverage of caves is five times greater than in epigenic karst systems. Hypogenic speleogenesis commonly results in more isotropic conduit permeability pervasively distributed within highly karstified areas measuring up to several square kilometers. Although being vertically and laterally integrated throughout conduit clusters, hypogenic systems, however, do not transmit flow laterally for considerable distances. Hypogenic speleogenesis can affect regional subsurface fluid flow by greatly enhancing initially available cross- formational permeability structures, providing higher local vertical hydraulic connections between lateral stratiform pathways for groundwater flow, and creating discharge segments of flow systems, the areas of low- fluid potential recognizable at the regional scale. Discharge of artesian karst springs, which are modern outlets of hypogenic karst systems, is often very large and steady, being moderated by the high karstic storage developed in the karstified zones and by the hydraulic capacity of an entire artesian system. Hypogenic speleogenesis plays an important role in conditioning related processes such as hydrothermal mineralization, diagenesis, and hydrocarbon transport and entrapment.

An appreciation of the wide occurrence of hypogenic karst systems, marked specifics in their origin, development and characteristics, and their scientific and practical importance, calls for revisiting and expanding the current predominantly epigenic paradigm of karst and cave science.


Cave Geology, 2007, Palmer A. N.
Cave Geology is the definitive book on the subject by an internationally recognized authority. It can be easily understood by non-scientists but also covers a wide range of topics in enough detail to be used by advanced researchers. Illustrated with more than 500 black-and-white photographs and 250 diagrams and maps, this book is dedicated to anyone with an interest in caves and their origin. Topics include: CONTENTS Preface 1 Speleology the science of caves Cave types Cave exploring Nationwide speleological organizations Searching for caves Cave mapping Preparation of a cave map Cave science Underground photography Show caves Cave preservation and stewardship 2 Cave country Geologic time Landscape development Surface karst features Paleoleokarst Pseudokarst The scale of karst features Distribution of karst and caves The longest and deepest known caves 3 Cavernous rocks Rock types Soils and sediments Stratigraphy Highly soluble rocks Rock structure Rock and mineral analysis A brief guide to rock identification 4 Underground water in karst Types of underground water Vadose flow patterns Phreatic flow patterns Aquifers Nature of the karst water table The freshwater-seawater interface Groundwater hydraulics Flow measurements Use of flow equations in cave interpretation Measuring the flow of springs and streams Groundwater tracing Interpreting groundwater character from tracer tests and flood pulses Quantitative dye tracing 5 Chemistry of karst water Simple dissolution Dissoltion of limestone and dolomite How much rock has dissolved? pH Undersaturation and supersaturation Epigenic and hypogenic acids Chemical interactions Dissolution rates Dissolution of poorly soluble rocks Microbial effects on chemistry Isotopes and their use Analysis of spring chemistry A chemical cave tour Chemical field studies 6 Characteristics of solution caves Cave entrances Passage types Passage terminations Cave rooms Cave levels Cave patterns Minor solution features in caves Interpreting flow from scallops Cave sediments Bedrock collapse Cave biology 7 Speleogenesis: the origin of caves Basic concepts Development of ideas about cave origin Comprehensive views of cave origin Rates of cave enlargement Insight from computer modeling Life cycle of a solution cave 8 Control of cave patterns by groundwater recharge Sinkhole recharge: branchwork caves The problem of maze caves Floodwater caves Caves formed by diffuse flow Hypogenic caves Polygenetic caves Influence of climate 9 Influence of geology on cave patterns Distribution of soluble rocks Influence of rock type Influence of geologic structure Relation of caves to landscape evolution A guide to cave patterns 10 Cave minerals Origin and growth of cave minerals Origin of common cave minerals Speleothem types Speleothem growth rates Speleothem decay 11 Caves in volcanic rocks Volcanic processes and landscapes Types of lava caves Origin and character of lava-tube caves Speleogens and speleothems in lava caves Time scale of lava caves 12 Cave meteorology and internal weathering Composition of cave air Cave temperatures Air movement Evaporation and condensation Weathering in the cave atmosphere Chemical zones in air-filled caves 13 Caves and time Relative and numerical ages Determining cave ages Studies of past climates Caves through the ages 14 Geologic studies of caves Field mapping Calibrating survey instruments Geologic interpretions Testing interpretations for validity Detailed analysis of a cave Further goals 15 Application of cave geology to other geosciences The problem of sampling bias Water supply Engineering applications Land management Interpretation of geologic processes Petroleum geology Mining Scientific frontiers The limits of discovery Glossary References Index Conversion between U.S. and metric units

Hypogenic speleogenesis within Seven Rivers Evaporites: Coffee Cave, Eddy County, New Mexico, 2008, Stafford K. W. , Land L. , Klimchouk A.

Coffee Cave, located in the lower Pecos region of southeastern New Mexico, illustrates processes of hypogenic speleogenesis in the middle Permian Seven Rivers Formation. Coffee Cave is a rectilinear gypsum maze cave with at least four stratigraphically-distinct horizons of development. Morphological features throughout the cave provide unequivocal evidence of hypogenic ascending speleogenesis in a confined aquifer system driven by mixed (forced and free) convection. Morphologic features in individual cave levels include a complete suite that defines original rising flow paths, ranging from inlets for hypogenic fluids (feeders) through transitional forms (rising wall channels) to ceiling half-tube flow features and fluid outlets (cupolas and exposed overlying beds). Passage morphology does not support origins based on epigenic processes and lateral development, although the presence of fine-grained sediments in the cave suggests minimal overprinting by backflooding. Feeder distributions show a lateral shift in ascending fluids, with decreasing dissolutional development in upper levels. It is likely that additional hypogenic karst phenomena are present in the vicinity of Coffee Cave because regional hydrologic conditions are optimum for confined speleogenesis, with artesian discharge still active in the region.


Epigene and Hypogene Gypsum Karst Manifestations of the Castile Formation: Eddy County, New Mexico and Culberson County, Texas, USA., 2008, Stafford K. , Nance R. , Rosaleslagarde L. And Boston P. J.
Permian evaporites of the Castile Formation crop out over ~1,800 km2 in the western Delaware Basin (Eddy County, New Mexico and Culberson County, Texas, USA) with abundant and diverse karst manifestations. Epigene karst occurs as well-developed karren on exposed bedrock, while sinkholes dominate the erosional landscape, including both solutional and collapse forms. Sinkhole analyses suggest that more than half of all sinks are the result of upward stoping of subsurface voids, while many solutional sinks are commonly the result of overprinting of collapsed forms. Epigene caves are laterally limited with rapid aperture decreases away from insurgence, with passages developed along fractures and anticline fold axes. Hypogene karst occurs as diverse manifestations, forming the deepest and longest caves within the region as well as abundant zones of brecciation. Hypogene caves exhibit a wide range of morphologies from complex maze and anastomotic patterns to simple, steeply dipping patterns, but all hypogene caves exhibit morphologic features (i.e. risers, outlet cupolas and half-tubes) that provide a definitive suite of evidence of dissolution within a mixed convection (forced and free convection) hydrologic system. Extensive blanket breccias, abundant breccia pipes and numerous occurrences of calcitized evaporites indicate widespread hypogene speleogenesis throughout the entire Castile Formation. Although most cave and karst development within the Castile outcrop region appears to have hypogene origins, epigene processes are actively overprinting features, creating a complex speleogenetic evolution within the Castile Formation.

Epigene and Hypogene Gypsum Karst Manifestations of the Castile Formation: Eddy County, New Mexico and Culberson County, Texas, USA., 2008, Stafford K. , Nance R. , Rosaleslagarde L. , Boston P. J.

Permian evaporites of the Castile Formation crop out over ~1,800 km2 in the western Delaware Basin (Eddy County, New Mexico and Culberson County, Texas, USA) with abundant and diverse karst manifestations. Epigene karst occurs as well-developed karren on exposed bedrock, while sinkholes dominate the erosional landscape, including both solutional and collapse forms. Sinkhole analyses suggest that more than half of all sinks are the result of upward stoping of subsurface voids, while many solutional sinks are commonly the result of overprinting of collapsed forms. Epigene caves are laterally limited with rapid aperture decreases away from insurgence, with passages developed along fractures and anticline fold axes. Hypogene karst occurs as diverse manifestations, forming the deepest and longest caves within the region as well as abundant zones of brecciation. Hypogene caves exhibit a wide range of morphologies from complex maze and anastomotic patterns to simple, steeply dipping patterns, but all hypogene caves exhibit morphologic features (i.e. risers, outlet cupolas and half-tubes) that provide a definitive suite of evidence of dissolution within a mixed convection (forced and free convection) hydrologic system. Extensive blanket breccias, abundant breccia pipes and numerous occurrences of calcitized evaporites indicate widespread hypogene speleogenesis throughout the entire Castile Formation. Although most cave and karst development within the Castile outcrop region appears to have hypogene origins, epigene processes are actively overprinting features, creating a complex speleogenetic evolution within the Castile Formation.


THE INFLUENCE OF HYPOGENE AND EPIGENE SPELEOGENESIS IN THEEVOLUTION OF THE VAZANTE KARST MINAS GERAIS STATE, BRAZIL, 2009, Bittencourt C. , Auler A. , Neto J. , Bessa V. , Silva M.

The advanced state of karsti?cation in the metadolomites of the Neoproterozoic Vazante Group has resulted in several geotechnical and hydrogeological problems in an underground zinc mine located in the city of Vazante, state of Minas Gerais, central Brazil, that have prompted detailed hydrogeological studies. The continuity of karsti?cation at depths below the regional base level suggests that hypogenic karsti?cation, driven by migration of ?uids from below due to hydrostatic pressure or other sources of energy may be a major player in the area. In this work several tools were used to understand the mechanisms of karsti?cation in the area, focusing on the relationship between karsti?cation and the location of ore bodies. The in?uence of both epigene and hypogene processes appears in the Vazante karstic evolution and has a relationship with the cave size. The study demonstrates that the size of voids decreases with depth. The largest cavities (greater than 15 meters) occur above the regional base level. This region is represented by the vadose zone, where epigenic karst processes predominate. Below this elevation, up to 250 meters in depth, a combination of epigene and hypogene processes occurs and the diameter of voids tends to decrease, being usually less than 10 meters. Below 250 meters, the phenomena of karsti?cation are strictly hypogenic and the diameter of voids is limited to less than 5 meters.


MORPHOLOGICAL INDICATORS OF SPELEOGENESIS: HYPOGENIC SPELEOGENS, 2009, Audra P. , Mocochain L. , Bigot J. Y. , Nobecourt J. C.

Hypogenic speleogenesis can be identi?ed at different scales (basinal ?ow patterns at the regional scale, cave patterns at cave system scale, meso- and micromorphology in cave passages). We focus here on small scale features produced by both corrosion and deposition. In the phreatic zone, the corrosion features (speleogens) are a morphologic suite of rising ?ow forms, phreatic chimneys, bubble trails. At the water table are thermo-sulfuric discharge slots, notches with ?at roofs. Above a thermal water table the forms re?ect different types of condensation runoff: wall convection niches, wall niches, ceiling cupolas, ceiling spheres, channels, megascallops, domes, vents, wall partitions, weathered walls, boxwork, hieroglyphs, replacement pockets, corrosion tables, and features made by acid dripping, such as drip tubes, sulfuric karren and cups. Each type of feature is described and linked to its genetic process. Altogether, these features are used to identify the dominant processes of speleogenesis in hypogenic cave systems. Hypogenic caves were recognized early, especially where thermal or sulfuric processes were active (MARTEL, 1935; PRINCIPI, 1931). However SOCQUET (1801) was one of the earliest modern contributors to speleogenetic knowledge, and probably the ?rst to identify the role of sulfuric speleogenesis by condensation-corrosion due to thermal convection. More recent major contributions evidenced the role of sulfuric speleogenesis and hydrothermalism (e.g. DUBLYANSKY, 2000; EGEMEIER, 1981; FORTI, 1996; GALDENZI AND MENICHETTI, 1995; HILL, 1987; PALMER AND PALMER, 1989). However, most of these case-studies were often considered as “exotic”, regarding the “normal” (i.e. epigenic) speleogenesis. Only recently, KLIMCHOUK (2007) provided a global model, allowing the understanding of “hypogenic” speleogenesis and gathering the characteristics of hypogenic caves. Consequently, the number of caves where a hypogenic origin is recognized dramatically increased during the last years. The hypogenic origin can be recognized at the regional scale (deep-seated karst in basins), at the scale of an individual cave system because of distinctive features in its pattern, by studying the morphology of the cave conduits, or at the local scale of wall features made by corrosion processes (i.e. speleogens). Such type of features depict the characteristics of local cave development, and by extension the characteristics of speleogenesis. The description and interpretation of hypogenic speleogens is generally scattered in the literature. The aim of this paper is to gather the most important hypogenic speleogens, considered here as indicators, and used for the identi?cation and characterization of the hypogenic speleogenesis. Our knowledge is based on the compilation of about 350 caves from the literature, and the study of some of the most signi?cant caves (AUDRA, 2007; AUDRA et al., 2002, 2006). In this paper, we focus on the speleogens (i.e. wall- scale corrosion features) as indicators of hypogenic speleogenesis; we exclude here solution feature at larger scale such as conduits and cave systems and depositional features (sediments). Some of the features observed in the sulfuric caves are speci?cally caused by this strong acid. Some features are closely associated with hydrothermalism. Other features that are widespread in hypogene caves are created without sulfuric in?uence. The following typology mainly takes into account the type of runoff. In con?ned settings with slow phreatic ?ow, cave features are common to all types of hypogene processes, whether they are sulfuric or not (i.e. carbonic, hydrothermal…). In uncon?ned settings, condensation-corrosion processes take place above the water table. These aerial processes, enhanced by the oxidation of sul?des by the thermal convections, and by the microbial processes, result in a large variety of cave features. Some features are closely related to speci?c processes. Consequently, they are considered as valuable indicators of the sulfuric speleogenesis.


Morphogenesis of hypogenic caves, 2009, Klimchouk A. B.

Hypogenic speleogenesis is the formation of solution-enlarged permeability structures by waters ascending to a cave-forming zone from below in leaky confined conditions, where deeper groundwaters in regional or intermediate flow systems interact with shallower and more local groundwater flow systems. This is in contrast to more familiar epigenic speleogenesis which is dominated by shallow groundwater systems receiving recharge from the overlying or immediately adjacent surface. Hypogenic caves are identified in various geological and tectonic settings, formed by different dissolutional mechanisms operating in various lithologies. Despite these variations, resultant caves demonstrate a remarkable similarity in patterns and meso-morphology, which strongly suggests that the hydrogeologic settings were broadly identical in their formation. Hypogenic caves commonly demonstrate a characteristic morphologic suite of cave morphs resulting from rising flow across the cave-forming zone with distinct buoyancy-dissolution components. In addition to hydrogeological criteria (hydrostratigraphic position, recharge-discharge configuration and flow pattern viewed from the perspective of the evolution of a regional groundwater flow system), morphogenetic analysis is the primary tool in identifying hypogenic caves. Cave patterns resulting from ascending transverse speleogenesis are strongly guided by the permeability structure in a cave formation. They are also influenced by the discordance of permeability structure in the adjacent beds and by the overall hydrostratigraphic arrangement. Three-dimensional mazes with multiple storeys, or complex 3-D cave systems are most common, although single isolated chambers, passages or crude clusters of a few intersecting passages may occur where fracturing is scarce and laterally discontinuous. Large rising shafts and collapse sinkholes over large voids, associated with deep hydrothermal systems, are also known. Hypogenic caves include many of the largest, by integrated length and by volume, documented caves in the world. More importantly, hypogenic speleogenesis is much more widespread than it was previously presumed. Growing recognition of hypogenic speleogenesis and improved understanding of its peculiar characteristics has an immense importance to both karst science and applied fields as it promises to answer many questions about karst porosity (especially as deep-seated settings are concerned) which remained poorly addressed within the traditional epigenetic karst paradigm.


HYPOGENE CAVES IN THE APENNINES (ITALY), 2009, Galdenzi S.

In the Apennine Mountains many examples of hypogene caves are known, generally related to present or past rise of sulfidic water that, mixing with oxygenated water of shallow flow systems, causes the sulfuric acid dissolution of limestone. The hypogene caves are generally located in small limestone outcrops covered by rocks of low permeability that in?uence the groundwater flowpaths. Some caves, however, are known also in hydrogeological massifs, where epigenic caves prevail. The hypogene caves show different patterns, ranging from phreatic to pure water table caves. The former prevail when karst evolved below the water table in structures almost completely covered by low permeability units; the latter occur in zones where a fast recharge of freshwater can reach the sulfidic water from the karst surface. The progressive lowering, thinning and removal of the low-permeability covers by non-karstic erosion processes can cause the progressive evolution from phreatic to water table caves. Active speleogenetic processes due to H2 S oxidation can be directly observed in different hydrogeologic settings: in highly permeable aquifers with ready recharge of freshwater (Frasassi caves), in thermal caves, below low permeability cover (Acquasanta Terme), or in marine thermal caves with salt water intrusion (Capo Palinuro).


ON THE ROLE OF HYPOGENE SPELEOGENESIS IN SHAPING THE COASTAL ENDOKARST OF SOUTHERN MALLORCA (WESTERN MEDITERRANEAN), 2009, Gines J. , Gines A. , Fornos J. , Merino A. , Gracia F.

The Migjorn region is one of the main karst areas in the island of Mallorca (Balearic Archipelago, Western Mediterranean) and has abundant coastal caves developed in Upper Miocene reefal carbonate rocks. In general terms it is an eogenetic karst platform in which littoral mixing dissolution processes usually represent the most important speleogenetic mechanism to be considered. Nevertheless, recent explorations in Cova des Pas de Vallgornera (Llucmajor Municipality), that nowadays has development exceeding 59 km of passages, raise interesting questions about the genesis of this outstanding littoral cave. An artificial entrance located at about 500 m from the coast line gives access to a complex assemblage of chambers and galleries, partially drowned by brackish waters, whose spatial disposition and morphological characteristics are strongly conditioned by the internal architecture of the Upper Miocene reef. The inner part of the cave consists of an extensive network of galleries that contain morpho-sedimentary features pointing to the possible participation of hypogene speleogenesis in the excavation of the system. Solutional features related to rising flow are abundant, together with Mn- and Fe-rich deposits and some minerals not known up to the l present in other caves of the region. The hypogene speleogenesis mechanisms that may have acted in Cova des Pas de Vallgornera could be associated with the feeble geothermal anomalies existing currently in the Llucmajor platform, related to important SW-NE faults which delimit the Campos subsidence basin in the southern end of Mallorca Island. The genesis of the cave system seems to be a complex matter including, besides coastal mixing processes and epigenic meteoric recharge, the participation of hypogene speleogenesis in an eogenetic unconfined setting.


PRINCIPAL FEATURES OF HYPOGENE SPELEOGENESIS, 2009, Klimchouk A. B.

Hypogenic and hypergenic (epigenic) karst systems are regularly associated with different types, patterns and segments of flow systems, which are characterized by distinct hydrokinetic, chemical and thermal conditions. Epigenic karst systems, which had long been the focus of most karst/speleogenetic research, are predominantly local systems receiving recharge from the overlying or immediately adjacent surface. Hypogenic karst is associated with discharge regimes of regional or intermediate flow systems dominated by upward flow, although mixing with local systems is commonly involved. Hypogenic speleogenesis tends to operate over long time spans, continuously or intermittently. Its main characteristic is the lack of genetic relationship with groundwater recharge from the overlying or immediately adjacent surface. Hypogenic karst may not be expressed at the surface and is largely climate-independent. Hypogenic speleogenesis is the formation of solution-enlarged permeability structures by waters ascending through a cave-forming zone from below. It develops in leaky confined conditions although it may continue through unconfined ones. Vertical hydraulic communication across lithological boundaries and different porosity systems allows deeper groundwaters in regional or intermediate flow systems to interact with shallower and more local systems, permitting a variety of dissolution mechanisms. There is a specific hydrogeologic mechanism inherent in hypogenic transverse speleogenesis (restricted input/output) that suppresses the positive flow-dissolution feedback and speleogenetic competition seen in the development of initial flowpath networks in hypergene cave genesis, accounting for the more uniform and pervasive conduit development found in the hypogene. Hypogenic caves are found in a wide range of geological and tectonic settings, basinal through folded, being formed by different dissolutional mechanisms operating in various lithologies. Despite these variations, the resulting caves tend to display remarkable similarity in their patterns and meso-morphology, strongly suggesting that the type of ?ow system is the primary control. Hypogenic caves commonly demonstrate a characteristic suite of cave morphologies resulting from rising ?ow across the cave-forming zone, with distinct buoyancy dissolution components. Cave patterns in hypogenic speleogenesis are guided by the initial permeability structure, its vertical heterogeneities (discordance in the permeability structure between adjacent beds) and the mode of water input to, and output from, the cave-forming zone. The latter again depends on relationships between permeability structures in the cave-forming zone and formations that lie below and above. Because of its “transverse flow” nature hypogenic speleogenesis has a clustered distribution in plan view, although initial clusters may merge during further development and extend over considerable areas. Recognition of the wide occurrence, significance and specific characteristics of hypogenic speleogenesis represents a major paradigm shift in karst science that answers many questions not satisfactorily addressed previously.


EPIGENE AND HYPOGENE CAVES IN THE NEOGENE GYPSUM OF THE PONIDZIE AREA (NIECKA NIDZIA?SKA REGION), POLAND, 2009, Urban J. , Andreychouk V. , Kasza A.

The Neogene gypsum of the Ponidzie area (SE part of the Niecka Nidzialska region) is in the same evaporite series as the giant hypogenic caves of the Western Ukraine. In spite of this, most of the Ponidzie gypsum caves were formed in later stages of speleogenesis and are epigenic. They differ from the Ukrainian caves in many features, e.g.: size, patterns and karst microforms. The epigenic caves of the Ponidzie are relatively short, horizontal and poorly branched conduits or flat, low chambers, situated close to the water table and related to the surface karst landforms. But a few caves characterized by the occurrence of karst features suggesting deep, hypogenic karsti?cation have been also recognized in this region. The most specific features of these caves are dome-like chambers with oval and lenticular concavities in the ceiling. Thus, although the dominance of epigene karst in Ponidzie is determined by factors such as hydrological properties of rock overlying and underlying the gypsum strata, structural patterns and joint systems in the gypsum itself (which differ from those of the Ukrainian karst region), local specific tectonic-hydrological conditions could also have generated karst during the deep circulation of artesian water in the early phases of the hydrological evolution. The hypogenic caves of Ponidzie occur in the axial part of a narrow syncline and on the downthrow side of a fault, so that the hypogenic karst is most likely connected with water circulation in marls underlying the gypsum and is limited to the deepest tectonic structures, with tectonic discontinuities being the routes for ground water circulation. This hypothesis should be verified by evaluation of larger numbers of hypogenic karst forms, if they can be found.


Karst features of the south-west part of the Piedmont Crimea from the standpoint of the theory of hypogene speleogenesis, 2009, Klimchouk A. B. , Amelichev G. N. , Tymkhina E. I.

The intense development of the theory and criteria of identification of hypogenic speleogenesis during last few years has stimulated re-interpretation of karst phenomena in many regions of the world. Recent research strongly suggest that solution features in the Piedmont Range of the Crimean Mountains, previously believed as being the result of epigenic karstification, were in fact formed in hypogenic environment due to ascending transverse flow in a stratified artesian system. Tectonically, the Piedmont Range of Crimea is an edge of the Scythian Plate, uplifted and partially eroded along the regional fault separating the plate from the folded region of the Mountain Crimea. The Cretaceous and Paleogene sequence is dipping 5 to 20o to north and north-west, where it plunges beneath the Neogene cover. It is exposed within the Piedmont Range as a series of distinct cuestas generally faced to south-east. Karst features are represented by 26 caves and abundant and diverse solution forms at the cuesta escarps. Most of karst features develop in two distinct limestone units of Paleocene (Danian) and Eocene but some are present in the underlying Maastrichtian unit of Cretaceous. There are strong and systematic evidences that the caves have hypogenic origin and that most of solution features at the escarps are remnants of morphologies of hypogenically karstified fractures, which walls are now exposed due to the block-fall retreat of the escarps. The features in various beds demonstrate strong lithostratigraphic control in their distribution and are vertically stacked into transverse complexes. Caves are fracturecontrolled, linear, or crude maze clusters, demonstrating the complete suit of morphologies indicative of hypogenic origin. Isolated cavities, expressed in the contemporary escarps as grottos and niches, as well as zones of spongework porosity, developed where laterally conductive beds of higher initial porosity were crossed by vertical fractures that once conducted rising fluids from a regional flow system.

The Piedmont Range of Crimea was a part of the Plain Crimea artesian basin during the post-Eocene time till the late Pliocene. Uplift and initial erosional entrenchment in the middle through late Pliocene caused the pattern of tectonically and geomorphologically guided zones of upward cross-formational discharge and hypogenic speleogenesis to establish. Further valley entrenchment in the region during Pleistocene shaped up the modern cuesta-like relief and drained the Cretaceous-Paleogene sequence. Hypogenically karstified fractures and caves, which are sub-parallel to valleys, provide zones of structural weakness along which blocks fall at the cuesta escarps exposing relict hypogenic morphologies.

The Piedmont Crimea Range, with its perfect and extensive exposures of the hypogenically karstified sequence, provides outstanding possibilities for studying patterns and morphologies of hypogenic speleogenesis, which is important for understanding its hydrogeological functioning and roles in the reservoir formation, especially in implication to the adjacent Plain Crimea artesian basin.


FLANK MARGIN CAVE DEVELOPMENT IN CARBONATE TALUS BRECCIA FACIES: AN EXAMPLE FROM CRES ISLAND, CROATIA, 2010, Otoni?ar Bojan, Buzjak Nenad, Mylroie John & Mylroie Joan
Plava Grota, Cres Island, Croatia, is a flank margin cave developed in a coastal setting in talus breccia facies. The internal cave geometry of small entrances, intersecting adjacent chambers, remnant dissolutional bedrock pillars, and low arches matches diagnostic features used to separate flank margin caves from epigenic stream caves on one hand, and sea caves on the other. Plava Grota is found, along with adjacent smaller caves, solely in a breccia facies that is most probably of Pleistocene age. This breccia is comprised of clasts derived from diagenetically mature, or telogenetic, Cretaceous carbonate rocks. The clasts are loosely cemented by vadose calcite cements. The breccia facies provide a three-dimensional porosity and permeability structure that behaves hydraulically in a manner similar to the high primary porosity and permeability of young eogenetic carbonate rocks in settings such as the Bahamas or Puerto Rico, and the many flow paths found in highly-tectonized telogenetic carbonate rocks in New Zealand. Plava Grota is the first described flank margin cave from the coastal carbonate rocks of the Adriatic Sea. According to present sea-level position in relation to the cave, fresh-water springs in and adjacent to the cave, general tectonic subsidence of the area and Quaternary eustatic sea-level fluctuations, we propose the hypotheses that the cave was primarily formed during the MIS 5e sea-level highstand.

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