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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That leakance is 1. the ratio k'/b', in which k' and b' are the vertical hydraulic conductivity and the thickness, respectively, of the confining beds [22]. 2. the rate of flow across a unit (horizontal) area of a semipervious layer into (or out of) an aquifer under one unit of head difference across this layer. synonymous with coefficient of leakage [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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Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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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 hypogenic caves (Keyword) returned 57 results for the whole karstbase:
Showing 16 to 30 of 57
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.


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.


HYPOGENE CAVE PATTERNS, 2009, Audra P. , Mocochain L. , Bigot J. Y. , Nobecourt J. C.

The hypogenic cave pattern re?ects the speleogenetic processes incvolved. Processes vary according to the depth in the aquifer, involving mixing corrosion by convergent ?ux and with meteoric water, cooling, sulfur oxidation, carbon dioxide degassing, and condensation-corrosion. Cave patterns are: isolated geodes, 2D and 3D multistory systems following joints and bedding planes, Giant phreatic shaft, Water table mazes, Isolated chambers, Upwardly dendritic spheres, Water table cave, ‘Smoking’ shafts. The development of caves by hypogene processes (i.e. “hypogenic speleogenesis”) corresponds to the formation of caves by water that recharges the soluble formation from below, driven by hydrostatic pressure or other sources of energy, independent of recharge from the overlying or immediately adjacent surface” (FORD, 2006). Hypogenic caves - often referred to as “thermal caves” - were often considered as an “exotic” side of the “normal” (i.e. meteoric) caves. Palmer (1991) estimated that about 10% caves have hypogenic origin. Recent studies (overview in KLIMCHOUK, 2007) have emphasized the speci?c hydrogeological background and shown that hypogenic caves are much more common than previously thought. The extreme diversity of settings (carbonic, sulfuric, thermal, cold, deep phreatic, shallow phreatic, vadose...) in different geological or geomorphological contexts produces a puzzling impression: each hypogenic cave seems to be unique, with few characteristics in common with the other hypogenic caves in terms of their patterns.


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.


ACTIVE HYPOGENE SPELEOGENESIS AND THE GROUNDWATER SYSTEMSAROUND THE EDGES OF ANTICLINAL RIDGES, 2009, Frumkin A.

It has been recently acknowledged that hypogenic caves are common in limestone terranes (e.g. KLIMCHOUK, 2000; AUDRA et al., 2002, 2007; AULER AND SMART, 2003; FORD AND WILLIAMS, 2007), with an extensive review by KLIMCHOUK (2007). Anticlinal ridges provide large recharge areas through which meteoric water may flow into confined zones around the peripheries during their history of uplift and associated denudation. The spatially varying stratal dips may create preferred flow routes within the confined zone and consequently promote hypogene speleogenesis at the most suitable sites for the water to rise again and discharge. Active speleogenetic sites thus may be found around the edges of anticlinal ridges where the potentiometric levels in the con?ned zone are high enough to promote the rising, transverse ?ow. Further away towards the adjoining synclinal basin, impermeable cover may be too thick to allow rising flow. The preferred sites for speleogenesis may migrate away from the anticlinal axis during the uplift process and associated lowering of groundwater levels. The common occurence of relict isolated hypogene caves in the Judean anticlinorium (FRUMKIN AND FISCHHENDLER, 2005) have led to the discovery of similar caves actively forming today. The Yarkon-Taninim regional aquifer is divided into lower and upper sub-aquifers, of which the lower one becomes (partly) con?ned near the anticlinal axis, while the upper sub- aquifer becomes con?ned at the western foothills. Upward flow is evident at the Ayalon Salinity Anomaly (ASA) where the upper sub-aquifer is still uncon?ned, so that rising water has much larger free space to ?ll in comparison with the nearby confined zone (FRUMKIN AND GVIRTZMAN, 2006). Approaching the watertable, the emerging rising flow can easily travel laterally along the highly permeable karstified zone. The rising ASA water is comparable to artesian springs, which discharge in the zone of lowest head of the upper aquifer. In the case of the ASA, however, the upward ?ow does not reach the open land surface but instead disperses laterally near the watertable. It may thus be considered an “underground delta”. The conceptual model consists of four-segment flow route: (1) rainwater recharge through outcrops on the anticlinal ridge; (2) lateral confined flow down to a depth of ~-700 m; (3) pressurized upward flow through discrete sub-vertical conduits; and (4) multidirectional pervasive flow close to the water table, with restricted output in which the rising water mingles with the ‘normal’ water of the upper aquifer. Maze caves fed by vertical conduits are typical for such an “underground delta”, as they disperse the flow laterally in many similar routes. Dense cave formation is observed to be associated with the upward flow of aggressive water. Within the “underground delta” the aggressiveness is consumed over short distances laterally away from the sub-vertical feeders. Such formation of large voids by dissolution far from the recharge zone implies renewed hydrochemical aggressiveness. The spatial location of the ASA is determined by three conditions that allow upward leakage from the deep sub-aquifer: (1) the location of the westernmost unconfined zone of the upper sub-aquifer, and its association with nearby confined regions; (2) the large upward head gradient; (3) spatial heterogeneities in the vertical permeability that are associated with tectonically disturbed zones.


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.


HYPOGENIC ASCENDING SPELEOGENESIS IN THE KRAKW-CZESTOCHOWA UPLAND (POLAND) EVIDENCE IN CAVE MORPHOLOGY AND SURFACE RELIEF, 2009, Tyc A.

Polygenetic and multiphase karst within Upper Jurassic limestone of the Krakw-Czestochowa Upland (South Poland) is characterized by a distinct stage of speleogenesis taking place in conditions of phreatic ascending circulation. This stage (or stages) is evidenced by both cave morphology and surface relief. Morphostratigraphic studies show that the hypogenic ascending features were early forms in the caves and later became integrated into cave systems. Conditions favorable for hypogenic caves development existed during a late Cretaceous-Paleogene phase of speleogenesis when the carbonate massif was covered by low permeability Cretaceous sediments and was subject to intense tectonic Laramian movements. In spite of the significant transformation of caves and their morphology by later vadose, epigenetic speleogenesis and denudation - especially under Pleistocene glacial and periglacial conditions - features of hypogenic ascending circulation are widely observed in the region. Relics of hypogene caves are common in the walls of rock monadnocks in the highest part of the Krakw-Czestochowa Upland.


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.


Hypogene gypsum karst and sinkhole formation at Moncalvo (Asti, Italy), 2010, Vigna B. , Fiorucci A. , Banzato C. , Forti P. , De Waele J.

In the morning of February 15th 2005, during excavation works in an underground gypsum quarry at Moncalvo (Monferrato area, Asti, Northern Italy), a water-bearing fracture was intercepted at level 134 m a.s.l. During the night a large amount of water (approximately 60,000 m3) and mud invaded the quarry tunnels reaching a height of 139 m a.s.l. the morning of the day after. Meanwhile a large sinkhole (20 m wide and 10 m deep) formed on the surface. Hydrogeological surveys were immediately carried out to follow the quickly evolving situation, while speleological and geomorphological fieldwork was made possible only seven months later. Two important caves were discovered both showing clear evidence of a hypogenic origin with sculpted morphologies due to slowly flowing water under pressure. The sinkhole formed by the collapse of one of the main chambers of the biggest of these caves, when buoyant support provided by the water started to decrease due to lowering of the virtual water table. The recharge of this karst system is from below and only very minor quantities of infiltration water come from the above lying surface, as has also been confirmed by hydrochemical analysis. This hypogene karst is completely invisible at the surface and develops entirely underground showing no relation whatsoever with the surface. Its presence is therefore extremely difficult to reveal and such types of karst can thus make up extremely dangerous situations. This is the first example of hypogene gypsum cave related to ascending waters in Italy.


Genesis and functioning of the Aix-les-Bains hydrothermal karst (Savoie, France): past research and recent advances, 2010, Hoblea F. , Gallinojosnin S. , Audra Ph.

Aix-les-Bains (Savoie, France) owes its name and reputation to the thermal springs that occur along the eastern shore of Lake Bourget, France largest natural lake. Although the city waters have been exploited since Antiquity, scientific investigations into the nature and characteristics of the hydrothermal karst from which they emerge did not begin until the early 19th century. The present article traces the history of these investigations and summarizes the results of more than two centuries of scientific research. Today, the only visible signs of karstification related to hydrothermal flows are to be found in the discharge zone in the Urgonian limestone anticline that rises above the city centre. These features are: – the Grotte des Serpents, which houses the Alun Spring, the system main natural discharge, – the Chevalley Aven, a blind chimney that was accidentally uncovered in 1996, – other hydrothermal springs that are too small to enter, including the Soufre Spring. Although scientific investigation of the thermal springs at Aix-les-Bains began in the early 19th century, it was not until the 1920s that scientists started examining the relationship between karstification and the state of the aquifer. E.A.Martel was the first researcher to describe the Aix-les-Bains site as an active hydrothermal karst, in a pioneering study published in 1935. Sixty years later, the discovery of the Chevalley Aven during building work on a new hydrotherapy center gave fresh impetus to research into the karstification of the Aix-les-Bains thermo-mineral aquifer. Recent studies have also investigated the deep aquifer below the karst, using data provided by boreholes. The Urgonian limestone karst at Aix-les-Bains is the site of mixing between thermal waters rising through the anticline and meteoric waters percolating from the surface. Meteoric infiltration is sufficiently high for the hydrological behavior of the thermal springs to be identical to that of exsurgences in gravity-fed, cold-water transmissive karsts. The Chevalley Aven is a shaft that descends 30 meters below the surface, thereby providing access to the ground-water at depth. Monitoring of the water quality in the aven has shown that the Legionella contamination of the springs was due to high concentrations of the bacteria in upstream passages in the karst. In 2006, dye-tracing tests confirmed the existence of a hydraulic connection between the Chevalley Aven and the Alun and Soufre Springs, the fact there is a single ascending hydrothermal conduit, which lies between the Chevalley Aven and the Alun Spring. In addition to providing a valuable source of information about the functioning of the thermo-mineral aquifer, the cavities at Aix-les-Bains are of great karstological interest, especially for the study of hypogene speleogenetic processes. The circulation of warm (40oC), sulfur-rich waters and vapours through the system has led to the development of conduits with specific morphologies and the precipitation of characteristic deposits. These features include: – “beaded” chimneys and galleries formed by the linking of spheres produced by condensation-corrosion. Diffuse karstification along bedding planes around the main conduit; – deposition of non-carbonate minerals (gypsum, native sulfur); – formation of biothems and biofilms on walls subject to condensation. The Grotte des Serpents is a horizontal cavity that formed at the upper limit of the water table. The Chevalley Aven is a hypogene chimney that was sculpted under vadose conditions by the release of sulfuric acid-rich vapours above the thermal water table. As well as a surface coating of microbial mats and the presence of bacterial flakes in the thermal water, the vadose parts of the Aix-les-Bains hydrothermal karst contain a characteristic microfauna and flora. These microorganisms are thought to play an active role in hypogene karstification processes.


Hypogenic caves in France. Speleogenesis and morphology of the cave systems, 2010, Audra Ph. , D'antoninebecourt J. C. , Bigot J. Y.

Hypogenic caves develop by recharge from below, not directly influenced by seepage from the overlying land surface. Several processes of speleogenesis are combined, involving CO2 or H2S produced at depth. If the recharge from depth remains uniform, the growth of selected fissures is prevented, giving rise to maze cave systems with an upward development trend, which is defined as “transverse speleogenesis” [Klimchouk, 2003]. Hypogenic caves are much fewer than epigenic caves (i.e. developed downwards by meteoric water with aggressivity derived from soil). In France, as in the rest of the world, hypogenic caves were poorly recognized until recently because of their lower frequency, subsequent epigenic imprint often hiding the true origin, and the absence of a global conceptual model. However, about a hundred of hypogenic caves have been identified recently in France. The extreme diversity of hypogenic cave patterns and features is due to the variety of geological and topographic settings and types of flow. Thermal caves are a sub-set of hypogenic caves. Active thermal caves are few and small (Mas d’En Caraman, Vallon du Salut). Often, thermal in fluences only occur as point thermal in feeders into epigenic caves (Mescla, Estramar). In addition to the higher temperature, they may be characterized by CO2 (Madeleine) or H2S degassing, by warm water flowing in ceiling channels, or by manganese deposits. The Giant Phreatic Shafts locate along regional active fault lines. They combine all characteristics (thermal, CO2, H2S), due to the fast rising of deep water. The Salins Spring has been explored by scuba diving down to –70 m. Such a hyperkarstification is responsible for the development of the deepest phreatic shafts of the world: pozzo del Merro, Italy (-392 m). Inactive hypogenic caves may be recognized by their specific mineralization or by the presence of large calcite spar. Metallic deposits are due to the rising of deep waters that are warm, aggressive, and low in oxidation potential. Mixing with meteoric water generates Mississippi Valley Type (MVT) sulfidic ores. Iron deposits as massive bodies (Lagnes) or onto microbial media (Iboussires, Malacoste) making specific facies, such as “black tubes”, iron flakes, and iron pool fingers. Other frequent minerals are Mn oxides and Pb sulfur. In such low thermal conditions, calcite deposits occur as large spar in geodes or as passage linings. Other inactive hypogenic caves may also be recognized by characteristic patterns, such as mazes. The relatively constant recharge into confined karst aquifers suppresses fissure competition, so they enlarge at similar rates, producing a maze pattern. In horizontal beds, mazes extend centrifugally around the upwelling feeder. The juxtaposition of multiple discrete vertical feeders produces extended horizontal mazes. In gently tilted structures, 2D mazes extend below aquitards, or along bedding or more porous beds (Saint-Sbastien). In thick folded limestone the rising hypogenic flow alternatively follows joints and bedding planes, producing a 3D maze cave in a stair case pattern (Pigette). Isolated chambers are large cupola-like chambers fed by thermal slots. Thermal convection of air in a CO2-rich atmosphere causes condensation-corrosion that quickly produces voids above the water table (Champignons Cave). Sulfuric acid caves with replacement gypsum are produced by H2S degassing in the cave atmosphere. H2S oxidizes to H2SO4, which corrodes the carbonate rock and replaces it with gypsum. The strongest corrosion occurs above the water table, where sulfide degassing and thermal convection produce strong condensation-corrosion. Caves develop head ward from springs and from thermo-sulfuric slots upward (Chevalley-Serpents System). The low-gradient main drains record base level positions and even the slightest stages of water-table lowering (Chat Cave). Hypogenic speleogenesis provides better understanding of the distribution of karst voids responsible for subsidence hazards and the emplacement of minerals and hydrocarbons.


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

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


Hypogenic caves in France. Speleogenesis and morphology of the cave systems, 2010, Audra Philippe, D’antoninobecourt Jeanclaude, Bigot Jeanyves

Hypogenic caves develop by recharge from below, not directly influenced by seepage from the over lying land surface. Several processes of speleogenesis are combined, involving CO2 or H2S produced at depth. If the recharge from depth remains uniform, the growth of selected fissures is prevented, giving rise to maze cave systems with an upward development trend, which is defined as “transverse speleogenesis” [Klimchouk, 2003]. Hypogenic caves are much fewer than epigenic caves (i.e. developed downwards by meteoric water with aggressivity derived from soil). In France, as in the rest of the world, hypogenic caves were poorly recognized until recently because of their lower frequency, subsequent epigenic imprint of tenhiding the true origin, and the absence of a global conceptual model. However, about a hundred of hypogenic caves have been identified recently in France. The extreme diversity of hypogenic cave patterns and features is due to the variety of geological and topographic settings and types of flow. Thermal caves are a sub-set of hypogenic caves. Active thermal caves are few and small (Mas d’En Cara man, Vallondu Salut). Often, thermal in fluences only occur as point thermal infeeders into epigenic caves (Mescla, Estra mar). In addition to the higher temperature, they may be characterized by CO2 (Madeleine) or H2S degassing, by warm water flowing in ceiling channels, or by manganese de posits. The Giant Phreatic Shafts locate along regional active faul tlines. They combine all characteristics (thermal, CO2, H2S), due to the fast rising of deep water. The Salins Spring has been explored by scuba diving down to –70 m. Such a hyperkars tification is responsible for the development of the deepest phreatic shafts of the world: pozzo del Merro, Italy (-392 m). Inactive hypogenic caves may be recognized by their specific mineralization or by the presence of large calcite spar. Metallic deposits are due to the rising of deep waters that are warm, aggressive, and low in oxidation potential. Mixing with meteoric water generates Mississippi Valley Type (MVT) sulfidicores. Iron deposits as massive bodies (Lagnes) or ontomicrobial media (Ibous sières, Malacoste) making specific facies, such as “black tubes”, iron flakes, and iron pool fingers. Other frequent minerals are Mn oxides and Pb sulfur. In such low thermal conditions, calcite deposits occur as large spar in geodes or as passage linings. Other inactive hypogenic caves may also be recognized by characteristic patterns, such as mazes. The relatively constant recharge into confined karst aquifers suppres ses fissure competition, so they enlarge at similar rates, producing a maze pattern. In horizontal beds, mazes extend centrifugally around the upwelling feeder. The juxtaposition of multiple discrete vertical feeders produces extended horizontal mazes. In gently tilted structures, 2D mazes extend below aquitards, or along bedding or more porous beds (Saint-Sé bastien). In thick folded limestone the rising hypogenic flow alternatively follows joints and bedding planes, pro ducing a 3D maze cave in a stair case pattern (Pigette). Isolated chambers are large cupola-like chambers fed by thermal slots. Thermal convection of air in a CO2-rich atmosphere causes condensation-corrosion that quickly produces voids above the water table (Champignons Cave). Sulfuric acid caves with replacement gypsum are produced by H2S degassing in the cave atmosphere. H2S oxidizes to H2SO4, which corrodes the carbonate rock and replaces it with gypsum. The strongest corrosion occurs above the water table, where sulfide degassing and thermal convection produce strong condensation-corrosion. Caves develop headward from springs and from thermo-sulfuric slots upward (Chevalley-Serpents System). The low-gradient main drains record base-level positions and even the slightest stages of water-table lowering (Chat Cave). Hypogenic speleogenesis provides better understanding of the distribution of karst voids responsible for subsidence hazards and the emplace ment of minerals and hydrocarbons.


Imprints of hydrocarbon-bearing basinal fluids on a karst system: mineralogical and fluid inclusion studies from the Buda Hills, Hungary, 2011, Poros Zsofia, Mindszenty Andrea, Molnar Ferenc, Pironon Jacques, Gyori Orsolya, Ronchi Paola, Szekeres Zoltan

Calcite veins and related sulphate–sulphide mineralisation are common in the Buda Hills. Also, abundant hypogenic caves are found along fractures filled with these minerals pointing to the fact that young cave-forming fluids migrated along the same fractures as the older mineralising fluids did. The studied vein-filling paragenesis consists of calcite, barite, fluorite and sulphides. The strike of fractures is consistent—NNW–SSE—concluding a latest Early Miocene maximum age for the formation of fracture-filling minerals. Calcite crystals contain coeval primary, hydrocarbon-bearing- and aqueous inclusions indicating that also hydrocarbons have migrated together with the mineralising fluids. Hydrocarbon inclusions are described here for the first time from the Buda Hills. Mixed inclusions, i.e., petroleum with ‘water-tail’, were also detected, indicating that transcrystalline water migration took place. The coexistence of aqueous and petroleum inclusions permitted to establish the entrapment temperature (80°C) and pressure (85 bar) of the fluid and thus also the thickness of sediments, having been eroded since latest Early Miocene times, was calculated (800 m). Low salinity of the fluids (<1.7 NaCl eq. wt%) implies that hydrocarbon-bearing fluids were diluted by regional karst water. FT-IR investigations revealed that CO2 and CH4 are associated with hydrocarbons. Groundwater also contains small amounts of HC and related gases on the basin side even today. Based on the location of the paleo- and recent hydrocarbon indications, identical migration pathways were reconstructed for both systems. Hydrocarbon-bearing fluids are supposed to have migrated north-westward from the basin east to the Buda Hills from the Miocene on.


Hypogenic caves in western Umbria (central Italy), 2011, Menichetti, Marco

Three karst areas located in the western sector of the Umbria Region (Central Italy) are here described: one north of Perugia, and the others to the south, close to Todi. All the end members of karst processes, from solution caves to quaternary travertine deposits, are present in this region, associated with CO2 and H2S emissions. The geological and hydrogeological aspects of the main karst systems are analyzed and their underground morphologies and patterns taken into account. Caves have different sizes and vary from a single conduit to complex systems, where the passages show features related to a possible hypogenic speleogenesis. In the area north of Perugia there are small horizontal and vertical solution caves developed in poorly karstified marly limestone, along fracture systems, where phreatic morphologies are prevalent. The endogenic CO2 emissions seem to drive the underground karst evolution. Pozzi della Piana, located west of the town of Todi, is a fossil branchform network cave system developed in a quaternary travertine and extending for more than 2500 m. The cave passages are arranged on at least two levels, with phreatic morphologies, cupola ceilings, and blind pits. Microcrystalline spalled gypsum blocks are associated with cusp features and wall pockets. The cave-forming process is believed to be linked to travertine deposition by supersaturated carbonate hydrothermal water rich in H2S. In the Parrano area, the underground karst system consists of solution caves extending for many hundreds of meters at different elevations in both sides of a small gorge. The cave patterns vary from single conduits to ramiform passages with anastomotic galleries and pits that intercept the water table with a temperature of 26°C, pCO2 of 0.1 atm, and H2S concentrations of 10 mg/l. Spongework, corrosion pockets, and cupola ceilings are common morphologies, with gypsum replacing limestone wall deposits. Cave formation by hypogenic speleogenesis is also well known in the Apennine karst system of M. Cucco and Frasassi, where both fossil and active processes are observable. The same processes are responsible for the genesis of these karst systems in different geological and hydrogeological contexts.


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