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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 solution flutes is see rillenkarren.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 hypogene cave (Keyword) returned 75 results for the whole karstbase:
Showing 61 to 75 of 75
HYPOGENE LIMESTONE CAVES IN GERMANY: GEOCHEMICAL BACKGROUND AND REGIONALITY, 2014, Kempe, S.

Germany exhibits a very diverse geological history. Thus, a large number of stratigraphically, petrographically and tectonically different carbonate and sulfate rocks exist that have been subject to karstification. Here, I discuss first the possible “agents” (sensu Klimchouk) of hypogene karstification. Three principally different processes are identified: water rising because of buoyancy (either thermally or concentration induced), in-situ oxidation of siderite, or rising gases (CO2, CH4 or H2S). Next, a rough overview of German caves and karst is presented. If applying the most pertinent epigene versus hypogene morphological characteristics, it becomes evident that hypogene caves occur in many different areas, often side-by-side with clearly epigene caves. For many areas, the agents of hypogene speleogenesis must remain unclear. This applies for most caves in the Paleozoic limestones of the Rhenish Schist Massif. Only the Iberg/Harz caves seem to be a clear case, with the world-wide highest concentrations of siderite weathering-induced caves occur. The large cavities discovered recently in the Blauhöhlen System and some of the deep pit caves in the Swabian Alb may have their explanation in volcanic CO2, having emanated from some of the 355 pipes of the Swabian volcanic field. Most striking is the high concentration of hypogene caves in the Franconian Alb. Many of them occur in a small area while other areas are devoid of larger caves. Here the tectonic situation suggests that fractures could have taped reservoirs of either sulfide or methane from below. The finding of goethitic crusts in the Bismarckgrotte may indicate that rising anaerobic gases could have been involved


RESERVOIR CHARACTERISTICS OF THE COMPLEX KARST OF THE LLUCMAJOR PLATFORM, MALLORCA ISLAND (SPAIN): TOOL FOR HYDROCARBON RESERVOIR APPRAISAL, 2014, Lapointe, P. A.

The development of porosity in carbonate platforms takes many forms. Dissolution porosity as a result of karst processes is unique as it produces organized porosity and permeability over a variety of scales, and can do so in very short periods of time, geologically speaking. Karst developed in the Miocene formations of the Mallorca Island exhibits a complexity that seems to be very similar to the Kashagan or Aktote (Kazakhstan) or Kharyaga (CIS) karst reservoirs architecture characterized by different phases of island karst (mixing water) type with caves of different sizes and sponge karst, reworked and partly filled by paleosoils related to plateau karst developed during major sea level drops and finally hydro- (geo)-thermal processes. The Miocene rocks of the Llucmajor platform in the southwest of Mallorca island exhibit the three main types of karst developments that occurred through time, linked or not to glacio-eustatic changes: -1 Island karst (the flank-margin model); -2 Meteoric karst; -3 Hydrothermal karst/ These developments allow defining the so-called Complex Karst. Each of the terms is identified by specific overprints found in drilled wells (logs and cores) or on outcrops. The outcrops and subcrops of Mallorca Island represent an excellent analogue for understanding the complexity of the past carbonate platforms which are hydrocarbon targets for the industry


HYPOGENE SPELEOGENESIS AND CO2: SUGGESTIONS FROM KARST OF ITALY, 2014, Menichetti, M.

The carbon dioxide produced in the soil and dissolved in the percolation water is considered as the main agent for karstification in the carbonate rocks. Superficial morphologies and underground caves are product of the corrosion of the limestone, while carbonate speleothems is the other end member of the process.
Hypogene speleogenesis driven by deep seated fluids is the cave formation processes for the main karst systems in the Apennines of Italy. Hydrogen sulfide and endogenic carbon dioxide are the main agents for underground karst corrosion and the soil carbon dioxide plays a secondary rule. The limestone corrosion driven by hydrogen sulfide produces gypsum deposits in caves that could be assumed as the indicator of the hypogene speleogenesis. The action of endogenic carbon dioxide in the cave formation, especially if it operates at lower temperature, is not easy to detect and the resulting cave morphology is not helpful to recognize the cave formation process.
The main sources of carbon dioxide in the underground karst system in the Apennines of Italy can be related to different processes driven by the endogenic fluids emissions. The crustal regional degassing seems to be the prevalent source for carbon dioxide in the karst massifs with the main release in the groundwater. Hydrogen sulfide and methane oxidation, possibly mediated by bacteria activity, are other sources in the buried Cenozoic sediments. Releasing of carbon dioxide along the faults and in the fractures occurring in the carbonate rocks is an important source, especially in the seismically active area. Finally, thermogenic reactions with carbonate rocks are well known as one of the main production mechanism of carbon dioxide released in the atmosphere.
Data from carbon dioxide monitoring in several caves show a relevant contribution of the endogenic carbon dioxide (about 75 %) in the karst system which drives the speleogenesis reactions and shapes the underground morphologies.


ACTIVE HYPOGENE SPELEOGENESIS IN A REGIONAL KARST AQUIFER: AYYALON CAVE, ISRAEL, 2014, Naaman I. , Dimentman C. , Frumkin A. ,

HYPOGENE VS EPIGENE CAVES: THE SULFUR AND OXYGEN ISOTOPE FINGERPRINT, 2014, Onac, B. P.

The classical epigene speleogenetic model in which CO2 is considered the main source of acidity has been challenged over the last three decades by observations that revealed cave passages unrelated to groundwater drainage routes and surface topography. Most of these passages show unusual morphologies, such are cupolas, floor feeders (i.e., inlets for deep-seated fluids), and huge irregular-shaped rooms that terminate abruptly, and often a rich and diverse mineral association. A hypogenetic speleogenetic pathway was proposed for this group of caves.
The presence of abundant gypsum deposits in caves with one or more of the passage morphologies listed above, have prompted scientists to suggest a new theory (i.e., sulfuric acid speleogenesis, SAS) of cave development. In the hypogenic SAS model, the source of acidity is the sulfuric acid produced by oxidation of H2S (originating from sulfate reduction or petroleum reservoirs) near or at the water table, where it dissolves the limestone bedrock and precipitates extensive gypsum deposits. SAS is now thoroughly documented from numerous caves around the world, with the best examples coming from the Guadalupe Mountains (NM), Frasassi caves (Italy), selected caves in France, Cueva de Villa Luz (Mexico), and Cerna Valley (SW Romania).
To date, discrimination between epigene and hypogene speleogenetic pathways is made using cave morphology criteria, exotic mineral assemblages, and the predominantly negative δ34S values for the cave sulfates. This presentation highlights the role sulfur and oxygen stable isotope analyses have in discriminating between epigene and hypogene caves.
Based on a number of case studies in caves of the Cerna Valley (Romania), we found that relatively S-depleted isotopic composition of cave minerals alone does not provide enough information to clearly distinguish SAS from other complex speleogenetic pathways. In fact, δ34S values of SAS by-products depend not only on the source of the S, but also on the completeness of S redox reactions. Therefore, similar studies to this are needed to precisely diagnose SAS and to provide information on the S cycle in a given karst system.
Integrating cave mineralogy, passage morphology, and geochemical studies may shed light on the interpretation of polygenetic caves, offering clues to processes, mechanisms, and parameters involved in their genesis (sulfate-dominated).


PER ASCENSUM CAVE MORPHOLOGIES IN THREE CONTINENTS AND ONE ISLAND, INCLUDING PLACES WHERE THEY SHOULDN’T OCCUR, 2014, Osborne, R. A. L.

Hypogene or per-ascensum, whatever you prefer to call them, caves that form from the bottom up have a great range of patterns in plan, large cavity morphology and an expanding, but specific suite of speleogens that distinguish them from fluvial caves formed by descending surface water. Once thought to be rare and unusual, caves or sections of caves with plans, large cavities and suites of “hypogene” speleogens are turning up in situations traditionally thought to have fluvial or even glacial origin. The role of condensation corrosion in the formation of cavities and speleogens remains controversial, but surprisingly some insights may come for processes in salt mines. Phantom rock formation and removal and similar processes involving removal of dolomitized bedrock, de-dolomitized bedrock, and almost trace-free removal of palaeokarst raise problems of both temporal relationships and of how to distinguish between the outcomes of recent and ancient processes. The presence of “hypogene” speleogens in both gneiss and marble caves in Sri Lankan of unclear origin adds to the complexity. Back in the early 1990s, before hypogene caves were de-rigour, workers such as David Lowe were puzzling about speleo-inception, how caves begin. Perhaps the rare occurrences of solution pockets in joints in obvious fluvial caves, such as Postojna Jama, are indicating that many more caves than we imagine are actually multi-process and multiphase and that “hypogene” processes of various types are significant agents of speleo-inception.


HELIUM ISOTOPES AS INDICATOR OF CURRENT HYPOGENIC KARST DEVELOPMENT IN TAURIDS KARST REGION, TURKEY, 2014, Ozyurt N. N. , Bayari C. S.

Hypogenic karst development by means of the aggressiveness of hydrothermal fluids driven and fed by mantle heat and mass flux is a known phenomenon. However, in cases when hydrothermal fluid cools down upon thermal conduction in the near-surface environment and is diluted by near-surface cool groundwater, evidences of this phenomenon may be erased completely. Recent data on the isotopes of helium dissolved in cool karst groundwater samples collected from three different karst aquifers in Turkey suggest an apparent mass flux from mantle, as well as from the crust. In the cases considered, helium content from the mantle increases with the increasing age of groundwater. All cases are located nearby the suture zones which may be easing the upward heat and mass flux. Despite sampling difficulties and high analysis costs, helium isotopes dissolved in cool karst groundwater seem to be useful tool to detect the current hypogenesis at the depths of karst aquifers


EVOLVING INTERPRETATIONS OF HYPOGENE SPELEOGENESIS IN THE BLACK HILLS, SOUTH DAKOTA, 2014, Palmer A. N. , Palmer M. V.

The origin of caves in the Black Hills has long been debated. Their history is long and complex, involving early diagenesis, meteoric karst (now paleokarst), deep burial, tectonic uplift, and, finally, enlargement of previous voids to the caves of today. The final stage is usually the only one recognized and is the topic of this paper. Genetic hypotheses include artesian flow, rising flow (preferably thermal), diffuse infiltration, and mixing of various water sources. The last process best fits the regional setting and water chemistry.  


ISOTOPIC STUDIES OF BYPRODUCTS OF HYPOGENE SPELEOGENESIS AND THEIR CONTRIBUTION TO THE GEOLOGIC EVOLUTION OF THE WESTERN UNITED STATES, 2014, Polyak V. J. , Asmerom Y. , Hill C. A. , Palmer A. N. , Provencio P. P. , Palmer M. V. , Mcintosh W. C. , Decker D. D. , Onac B. P.

Hypogene speleogenesis in the western United States is associated with a deep source of water and gases that rise and mix with shallow aquifer water. Caves are formed below the surface without surface expressions (ie, sinkholes, sinking streams), and byproducts of speleogenesis are precipitated during the late phase of hypogene speleogenesis. These byproducts provide geochemical and geochronological evidence of a region’s geologic history and include gypsum rinds and blocks, elemental sulfur, halloysite-10Å, alunite, natroalunite, and other sulfur-related minerals. The following speleogenetic and speleothemic features are common: alteration rinds, crusts, mammillaries, folia, rafts, and cave spar. The types of hypogene speleogenesis vary and many can be expressed in space and time in relation to paleo-water tables. We identify two general types: (1) H2S-H2SO4-dominated speleogenesis that takes place predominantly near a paleo-water table (a few meters above and below), and (2) CO2-dominated speleogenesis that mostly takes place 10s to 100s of meters below a paleo-water table, with latest-stage imprints within meters of the water table.
The Kane caves in Wyoming, and the Guadalupe Mountains caves in New Mexico and West Texas, are examples of H2S-H2SO4-dominated speleogenesis (also known as sulfuric acid speleogenesis, SAS), where deposits of H2S- and H2SO4-origin are the obvious fingerprints. The Grand Canyon caves in Arizona and Glenwood Caverns in Colorado are examples of CO2-dominated systems, where H2SO4 likely played a smaller role (Onac et al., 2007). Deeper-seated geode-like caves, like the spar caves in the Delaware Basin area, are probably CO2-dominated, and have formed at greater depths (~0.5 ± 0.3 km) below paleo-water tables. Caves in the Black Hills, South Dakota are composite and complex and show evidence for multiple phases of hypogene speleogenesis. In areas such as the Grand Canyon region, these paleo-water tables, when they existed in thick carbonate rock stratigraphy and especially at the top of the thick carbonate rock strata, were likely regionally relatively flat in the larger intact tectonic blocks.
Geochemical studies of these deposits are providing information about the timing of speleogenesis through U-Th, U-Pb, and Ar-dating. In addition, tracer data from isotopes of C, O, S, Sr, and U are indicators of the sources of water and gases involved in speleogenesis. From these studies, novel canyon incision and landscape evolution interpretations are appearing in the literature. Beyond this, the study of these byproduct materials seems to show evidence that the deeply sourced water and gases involved in hypogene speleogenesis in the western United States are generated during tectonic and volcanic activity, and may be related to mantle processes associated with formation of the Rocky Mountains, Colorado Plateau, Basin and Range province, and Rio Grande Rift.


DEVILS HOLE: ANTIKARST IN THE MOJAVE, 2014, Riggs, A. C.

HYPOGENE PALEOKARST IN THE TRIASSIC OF THE DOLOMITES (NORTHERN ITALY), 2014, Riva, A.

In the Triassic of successions of the Italian Dolomites (Northern Italy), there are several examples of different types of hypogene paleokarst, sometimes associated with sulfur or hematite ore deposits.The paleokarst features are related to a regional volcanic event occurred during the Ladinian (Middle Triassic) that affected several carbonate platforms of Anisian-Ladinian age.This study is focusing mainly on the Latemar paleokarst, in the Western Dolomites, and on the Salafossa area in the Easternmost Dolomites.
The karst at Latemar developed as the result of a magmatic intrusion located just below the isolated carbonate platform, developing a system of phreatic conduits and some underground chambers, not justified by the entity of the submarine exposure occurring at the top of the carbonate platform. Most of these features are located about 500 m below the subaerial unconformity and are filled with middle Triassic lavas. Only in one case, the filling is represented by banded crusts now totally dolomitized, with abundant hematite. In this case, the only way to explain the presence of the karst at this depth is to invoke a deep CO2 source allowing the dissolution of the carbonate at such depths: the fact that some phreatic conduits and a possible underground chamber are filled only with lavas is pointing toward an important role of volcanism in karst development.
Salafossa is a well-known mine located in the easternmost Dolomites and has been exploited until 1986, when all the activity ceased. The main metals, in this case, are Zn-Pb-Ba-Fe, exploited within a quite complex paleokarst system developed in several levels, filled by a complex mineralized sequence. The strong dissolution led to the development of voids aligned with the main fault controlling the mineralization, with a proper karst system with phreatic morphologies.


SPELEOGENESIS BY THE SULFIDIC SPRINGS AT NORTHERN SIERRA DE CHIAPAS, MEXICO, BASED ON THEIR WATER CHEMISTRY, 2014, Rosaleslagarde L. , Boston P. J.

Conspicuous brackish sulfidic springs have been described at the northern Sierra the Chiapas, Mexico. These springs are produced by a mixture between regional and local groundwater flow paths. The regional groundwater has an average Total Dissolved Ions of 3081 mg/L so it has a brackish composition. This brackish water is saturated with respect to calcite and dolomite but undersaturated with respect to gypsum, anhydrite and halite. The mass balance and the discharge rate are used to quantify the mass and volume of minerals that are dissolved by the brackish spring water following Appelo and Postma (1993). This quantification will allow comparing the various speleogenetic mechanisms in the area. This is considering the composition of the spring water is relatively constant over time, as it is suggested by periodic measurements at the Cueva de Villa Luz springs during the last 10 years.
Sulfur isotopes in the water are consistent with anhydrite dissolution as the main source of the sulfate to the brackish spring water. Thus, the average 6 mol/L of sulfate in the brackish springs are produced by dissolution of 6 mol of anhydrite after subtracting the sulfate that could result from evapotranspiration of rainwater. Each liter of brackish water dissolved an average of 882 mg of anhydrite, which are equivalent to dissolving 0.36 cm3 of this mineral considering a density of 2.981 g/cm3. Additionally, using the average brackish water discharge rate of 144 L/s, an average of 57 g of anhydrite are being dissolved each second per every liter of brackish water. This is a minimal value because some of the sulfate in the water is used by sulfate-reducing bacteria in the subsurface to produce the hydrogen sulfide in the spring water. The anhydrite subject to dissolution is found interbedded in the Cretaceous carbonates, either from the subsurface at 4,000 m below sea level to the carbonate outcrops.
Similarly, we can calculate the volume of halite that is being dissolved by the brackish springs, considering chloride is a conservative element and subtracting the chloride concentration from the rainwater from that of the spring water following Appelo & Postma (1993). The 22 mol/L of chloride in the brackish water can result from dissolution in the subsurface of 22 moles or 1.3 g of halite per liter of brackish water. This mass of halite dissolved is equal to 0.59 cm3 considering a density of 2.168 g/cm3. Alternatively, 118 g of halite are dissolved per second per each liter of brackish water if we use the average discharge rate of 144 L/s.
Even when the brackish springs are oversaturated with respect to calcite and dolomite, their dissolution is still possible due to the common ion-effect of calcium after anhydrite dissolution and by mixing of waters with different compositions. A range of 10 to 80 % of brackish water from the regional aquifers mixes with fresh water from the local aquifer based on their water chemistry. Additionally, sulfuric acid speleogenesis occurs due to the oxidation of hydrogen sulfide to sulfuric acid.
Finally, the increase in the chloride concentration of the fresh water springs with respect to the concentration in rainwater was used to estimate that from the 4000 mm/y of annual precipitation, only 4%, 158 to 182 mm/y, recharge the aquifers. This low percentage is slightly higher than the 3.3% recharge in marls, marly limestone, silts and clays (Sanz et al., 2011), probably because of the relatively small area of carbonate outcrops over the entire region and the lack of recharge in altitudes higher than 1500 m above sea level.
Sulfuric acid is the most obvious speleogenetic mechanism occurring in the caves of the northern Sierra de Chiapas, Mexico due to the high hydrogen sulfide concentration in the spring water. In addition, the location of the springs at a zone of regional and local discharge where waters from different composition converge and mix, and the amount of mixing calculated suggests mixing is also an important speleogenetic mechanism. However, the depth and the time constrains at which these two hypogenic mechanisms occur is still unknown. The relatively low rainwater recharge rate suggests epigenesis is limited. Most likely, the porosity created by dissolution of anhydrite and halite in the subsurface is occluded by the precipitation of calcite. Chemical modeling and petrography will help to elucidate the order of the reactions occurring in the subsurface.


PONDERING THE IMPORTANCE OF SUBAERIAL CORROSION AS A SPELEOGENETIC AGENT, 2014, Sasowsky, I. D.

Subaerial corrosion has been recognized as an important cave modifying process in limited settings. But is it possible that we overlook its importance in other cases? Could it actually be a significant speleogenetic agent in its own right? Numerous corroding agents have been identified including sulfuric acid, carbonic acid, ambient water vapor, and thermal water vapor. Morphogenetic features have been described, and cautions issued about possible confusion with hypogene features. Theoretical calculations seem to limit the importance of corrosion in many settings, but it appears that great care must be taken, especially for possible confusion between “hypogene” morphologies in a cave.
Some caves in the Iberian Range (Spain) seem undoubtedly hypogene in origin based on hydrologic constraints. They also contain morphologies that are consistent with this origin. But, extreme corrosion of speleothems and bedrock may be masking the nature of the cave morphology post-drainage of the forming waters. Topographic position of some caves suggests the possibility of a strong component of subaerial corrosion as the cave forming agent


THE METHODOLOGICAL STRENGTH OF THE HYDROGEOLOGICAL APPROACH TO DISTINGUISHING HYPOGENE SPELEOGENESIS, 2014, Klimchouk, A. B.

Defined in the most general way, hypogene speleogenesis is the origin of caves in which the cave-forming agency comes from depth, in contrast to epigene speleogenesis in which the cave-forming agency (meteoric recharge and its inherent or soil-derived aggressiveness) originates at the surface. A more specific definition should rely on attributes of the cave-forming agency which are most suitable and efficient for discrimination between epigene and hypogene origin of caves.
Relying on the determination of a source of the aggressiveness in distinguishing hypogene speleogenesis is the legitimate approach but it is not a methodologically sound and practically efficient one.
The hydrogeological approach and the reference to upwelling groundwater circulation in the definition of hypogene speleogenesis provide a theoretically and methodologically sound basis not only for identifying the type of speleogenesis, but also for spatial and temporal prognosis of hypogene speleogenesis.


Hypogene speleogenesis in dolomite host rock by CO2-rich fluids, Kozak Cave (southern Austria), 2015,

A growing number of studies suggest that cave formation by deep-seated groundwater  (hypogene) is a more common process of subsurface water-rock interaction than previously  thought. Fossil hypogene caves are identified by a characteristic suite of morphological  features on different spatial scales. In addition, mineral deposits (speleothems) may provide  clues about the chemical composition of the paleowater, which range from CO2-rich to  sulfuric acid-bearing waters. This is one of the first studies to examine hypogene cave  formation in dolomite. Kozak Cave is a fossil cave near the Periadriatic Lineament, an area  known for its abundance of CO2-rich springs. The cave displays a number of macro-, mesoand  micromorphological elements found also in other hypogene caves hosted in limestone,  marble or gypsum, including cupolas, cusps, Laughöhle-type chambers and notches. The  existance of cupolas and cusps suggests a thermal gradient capable of sustaining free  convection during a first phase of speleogenesis, while triangular cross sections (Laughöhle  morphology) indicate subsequent density-driven convection close to the paleowater table Notches mark the final emergence of the cave due to continued rock uplift and valley  incision. Very narrow shafts near the end of the cave may be part of the initial feeder system,  but an epigene (vadose) overprint cannot be ruled out. Vadose speleothems indicate that the  phreatic phase ended at least about half a million years ago. Drill cores show no evidence of  carbon or oxygen isotope alteration of the wall rock. This is in contrast to similar studies in  limestone caves, and highlights the need for further wall-rock studies of caves hosted in  limestone and dolomite


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