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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 thenardite is a cave mineral - na2so4 [11].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for geothermal (Keyword) returned 74 results for the whole karstbase:
Showing 1 to 15 of 74
Summit Firn Caves, Mount Rainier, Washington, 1971, Kiver Eugene P. , Mumma Martin D. ,
Heat and steam from the crater fumaroles have melted over 5700 feet (1737 meters) of cave passage in the ice-filled east crater of Mount Rainier. The caves are in approximate balance with the present geothermal heat release. Future changes in the thermal activity of the summit cone will cause corresponding changes in cave passage dimensions, location, and ceiling and wall ablation features

Identification of the origin of oreforming solutions by the use of stable isotopes, 1977, Sheppard S. M. F. ,
SynopsisThe four major different types of water -- magmatic, metamorphic, sea water and/or connate, and meteoric water -- have characteristic hydrogen (D/H) and oxygen (18O/16O) isotope ratios. Applied to the analysis of isotopic data on hydrothermal minerals, fluid inclusions and waters from active geothermal systems, these ratios indicate that waters of several origins are involved with ore deposition in the volcanic and epizonal intrusive environment. Water of a single origin dominates main-stage mineralization in some deposits: magmatic -- Casapalca, Peru (Ag-Pb-Zn-Cu); meteoric -- Butte, Montana (Cu-Zn-Mn), epithermal deposits, e.g. Goldfield, Tonopah, Nevada (Ag-Au), Pachuca, Mexico (Ag-Au), San Juan Mountains District, Colorado (Ag-Au-Pb-Zn); sea water -- Troodos, Cyprus (Fe-Cu), Kuroko, Japan (Fe-Cu-Pb-Zn). Solutions of more than one origin are important in certain deposits (magmatic and meteoric -- porphyry copper and molybdenum deposits) and are present in many. In the porphyry Cu-Mo deposits the initial major ore transportation and alteration processes (K-feldspar-biotite alteration) are magmatic-hydrothermal events that occur at 750-500{degrees}C. These fluids are typically highly saline Na-K-Ca-Cl-rich brines (more than 15 wt % equivalent NaCl). The convecting meteoric-hydrothermal system that develops in the surrounding country rocks with relatively low integrated water/rock ratios (less than 0.5 atom % oxygen) subsequently collapses in on a waning magmatic-hydrothermal system at about 350-200{degrees}C. These fluids generally have moderate to low salinities (less than 15 wt % equivalent NaCl). Differences among these deposits are probably in part related to variations in the relative importance of the meteoric-hydrothermal versus the magmatic-hydrothermal events. The sulphur comes from the intrusion and possibly also from the country rocks. Deposits in which meteoric or sea water is the dominant constituent of the hydrothermal fluids come from epizonal intrusive and sub-oceanic environments where the volcanic country rocks are fractured or well jointed and highly permeable. Integrated water/rock ratios are typically high, with minimum values of 0.5 or higher (atom % oxygen) -- the magmatic water contribution is often drowned out'. Salinities are low to very low (less than 10 wt % equivalent NaCl), and temperatures are usually in the range 350-150{degrees}C. The intrusion supplies the energy to drive the large-scale convective circulation system. The sulphur comes from the intrusion, the country rocks and/or the sea water. Argillic alteration, which occurs to depths of several hundred metres, generated during supergene weathering in many of these deposits is isotopically distinguishable from hydrothermal clays

The Geothermal nature of the Floridan Plateau, 1977, Smith Douglass L. , Griffin George M.

Hydrogeology related to geothermal conditions of the Floridan Plateau -- Geologic and geomorphic setting -- The principal artesian zone -- The Boulder zone -- Injection sites in Florida -- The Geothermal regime of the Floridan Plateau -- Vertical temperature profiles in Floridan Aquifer system, geographic distribution of temperature in Floridan Aquifer system -- Surface evidence of thermal upwelling -- Humble-Lowndes-Treadwell No. 1 -- Warm mineral springs sinkhole -- The Mud hole submarine spring -- Comparison of theoretical and field studies -- The Dolomite question and cavity formation, Geothermal gradients below the Floridan Aquifer system -- Heat flow in Florida oil test holes and indications of oceanic crust beneath the Southern Florida-Bahamas Platform -- Spatial distribution of ground water temperature in South Florida -- Regional significance of Florida heat flow values -- Thermal model for the Florida crust -- A Model of subsidence with inhomogeneous heat production.


Splogense hydrothermale dans les Bibans (Atlas Tellien, Algrie), 1983, Collignon, B.
HYDROTHERMAL SPELEOGENESIS IN THE BIBANS (ATLAS TELLIEN, NORTH ALGERIA) - The Azrous are two small limestone mountains jutting out from wide marl spaces (the Tellian sheets) in the region of the Bibans. Their surface is not really a karst but they contain many caves, which have been caused by thermal waters. The seepage is so weak that these caves have been very well preserved and so we can study old geothermal carbonate aquifers. This study shows the main morphological, structural, sedimentological and mineralogical features of such caves.

DIAGENESIS OF AN UPPER TRIASSIC REEF COMPLEX, WILDE-KIRCHE, NORTHERN CALCAREOUS ALPS, AUSTRIA, 1994, Satterley A. K. , Marshall J. D. , Fairchild I. J. ,
The Wilde Kirche reef complex (Early-Late Rhaetian) grew as an isolated carbonate structure within the shallow Kossen Basin. At the Triassic/Jurassic boundary a single brief(c. 10-50 ka) period of subaerial exposure occurred. The preserved karst profile (70 m thick) displays a vadose zone, enhanced dissolution at a possible palaeo-watertable (5-15m below the exposure surface), and a freshwater phreatic zone. Karst porosity was predominantly biomouldic. primary cavities and biomoulds were enlarged and interconnected in the freshwater phreatic zone; cavity networks developed preferentially in patch reef facies. Resubmegence of the reef complex allowed minor modification of the palaeokarst surface by sea floor dissolution and Fe-Mn crust deposition on a sediment-starved passive margin. Fibrous calcite (FC), radiaxial fibrous calcite (RFC) and fascicular optic calcite (FOC) cements preserved as low Mg calcite (LMC) are abundant in primary and karst dissolution cavities. FC cement is restricted to primary porosity, particularly as a synsedimentary cement at the windward reef margin. FC, RFC and FOC contain microdolomite inclusions and show patchy non-/bright cathodoluminescence. delta(18)O values ofnon-luminescent portions (interpreted as near original) are -1.16 to -1.82 parts per thousand (close to the inferred delta(18)O of calcite precipitated from Late Triassic sea water). delta(13)C values are constant ( to .2 parts per thousand). These observations suggest FC, RFC and FOC were originally marine high Mg calcite (HMC) precipitates, and that the bulk of porosity occlusion occurred not in the karst environment but in the marine environment during and after marine transgression. The HMC to LMC transition may have occurred in contact with meteoric water only in the case of FC cement. The most altered (brightly luminescent) portions of RFC/FOC cements yield delta(18)O = -2.44 to -5.8 parts per thousand, suggesting HMC to LMC alteration at up to 34 degrees C, in the shallow burial environment at depths of 180-250 m. Abundant equant cements with delta(18)O = -4.1 to -7.1 parts per thousand show crisp, uniform or zoned dull luminescence. They are interpreted as unaltered cements precipitated at 33-36 degrees C at 200-290 m burial depth, from marine-derived fluids under a slightly enhanced geothermal gradient. Fluids carrying the equant cements may have induced the HMC to LMC transition in the fibrous cements

Geochemistry of submarine warm springs in the limestone cavern of Grotta Azzurra, Capo Palinuro, Italy: evidence for mixing-zone dolomitisation, 1996, Stuben Doris, Sedwick Peter, Colantoni Paolo,
Subtidal springs in and around the submarine limestone cavern of Grotta Azzurra, at Capo Palinuro, Italy, discharge fluids which are warm (-, Na and Mg2, and enriched in Si, alkalinity, Ca2, Sr2, Mn, NH4, PO43- and H2S, relative to surrounding seawater. The compositions of the warm fluid samples collected in and around the cave define mixing lines which suggest dilution of a single thermal fluid (T >= 23[deg]C) by cool overlying seawater (T= 17-17.6[deg]C). The chemical data suggest that the proposed thermal fluid contains two components, one derived from seawater ( 10%). Excess Si, alkalinity, Ca2, Sr2 and Mn relative to seawater are likely derived from the groundwater component or dissolution/hydrothermal alteration of the host rocks. Magnesium has been removed from the seawater component in exchange for Ca2, due to dolomitisation of the limestone and/or hydrothermal alteration reactions. Saturation-state calculations suggest that the vented fluids are near saturation with respect to calcite and supersaturated with respect to dolomite. This and the presence of dolomite in the host rocks and cave-floor sediments suggest that 'mixing-zone' dolomitisation of the limestones is occurring, perhaps kinetically assisted by elevated temperature and/or bacterial mediation in the reducing subseafloor zone. One possible 'end-member' condition is considered for the thermal fluid -- zero-Mg -- which suggests an end-member temperature of 50.5[deg]C and a fluid composition derived from ~ 38% seawater and ~ 62% groundwater. The heat source for the circulating fluids is uncertain, but may involve warm underlying igneous rocks or heating via the geothermal gradient. A continuous in-situ record of vent-fluid temperature, salinity, pH and O2 concentration collected within the cavern is consistent with our interpretation of the fluid origin, and suggests that tidal forcing affects circulation and venting of the warm fluids

Gypsum Trays in Torgac Cave, New Mexico, 1998, Doran, L. M. , Hill, C. A.
Mount St. Helens is an active dacitic volcano, which is currently in a semi-dormant state after a catastrophic explosive eruption in May 1980. A dacite dome occupies the crater and plugs the volcanic vent. The crater area has been progressively covered by a layer of snow, firn, and glacier ice since as early as 1986. Heat, steam, and volcanic gases from the crater fumaroles melted over 2415 meters of cave passage in the crater ice mass. The caves are in approximate balance with the present geothermal heat release. Future changes in the thermal activity will influence the dimensions, location, ceiling, wall, and wall ablation features of these caves. Cave passages are located above fumaroles and fractures in and adjacent to the crater lava dome. Cave passages gradually enlarge by ablation, caused by outside air circulation and by geothermal sources beneath the ice. The passages form a circumferential pattern around the dome, with entrance passages on the dome flanks. Passages grow laterally and vertically toward the surface, spawning ceiling collapse.

Air Temperature and Relative Humidity Study: Torgac Cave, New Mexico, 1998, Forbes, J.
The crater ice body has been expanding since 1986 and its mean density increases each year. It possesses at least two active crevasses. Trends and changes in geothermal activity in the crater of Mount St. Helens have been noticeable through cave passage observation and re-mapping.

Microclimate Study of Kartchner Caverns, Arizona, 1999, Buecher, R. H.
A detailed two-year study of the microclimate in Kartchner Caverns determined that the most significant problem in maintaining the microclimate of the cave is the potential for drying out due to increased airflow. Two factorsa small, hypothesized upper second entrance and a slight geothermal warming of the cavecontrol natural airflow and increase the amount and intensity of winter air exchange. The average amount of water reaching the cave is 7.9 mm/yr, only twice the amount lost by evaporation from cave surfaces. Kartchner Caverns has an average relative humidity (RH) of 99.4%. Useful measurement of RH required a dewpoint soil psychrometer rather than a sling psychrometer. Moisture loss from cave surfaces is proportional to relative humidity, and small changes in RH have a dramatic effect on evaporation from cave surfaces. A lowering of RH to 98.7% would double the evaporation rate and start to dry out the cave. The volume of air exchange in the cave was estimated from direct measurement, changes in CO2 concentration, and temperature profile models. All of these methods are consistent with a volume of 4,000 m/day entering the cave during the winter. During the summer, the direction of airflow reverses and the volume of air leaving the cave is much smaller than during the winter months. Surface air is almost always drier than cave aironly during the summer months when rain occurs does outside air contain more moisture. However, the rate of air exchange is greatly reduced during the summer, which minimizes any potential effect of increased outside moisture. Radon concentrations in the cave are high enough to be of concern for long-time employees but not for the general public. Radon222 concentrations average 90 pCi/L and radon daughters average 0.77 Working Levels (WL) in the main part of the cave. During the winter, radon levels in the Echo Passage are up to six times higher than the rest of the cave due to the passages stable microclimate and limited air movement, which greatly reduces radon removal by plateout. Natural removal by ventilation is only a minor factor in determining radon levels in the rest of the cave.

CO2 source-sink in karst processes in karst areas of China, 1999, Jiang Z. C. , Yuan D. X. ,
The CO2 source-sink of atmospheric greenhouse has a close relationship with karst processes. The corrosion of carbonate rocks lends to the sink of atmospheric CO2, whereas the deposition of carbonate rocks gives off CO2 into atmosphere, which is one of the sources of atmospheric CO2. According to the exposed areas of carbonate rocks in China, the flux of atmospheric CO2 consumed in karst processes is estimated at about 1.77 x 10(13) g CO2/a, Considering the global karst area the flux Of atmospheric CO2 consumed in corrosion may be an important parr of the missing sink. And the sink has a tendency of continuous increase. The release of CO2 from karst water is usually less than the sink of atmospheric CO2 consumed in karst processes. But in active tectonic zone the release of high CO2 concentration of mantle source in the geothermal karst water should not be neglected

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

Variability of karstic permeability between unconfined and confined aquifers, Grand Canyon region, Arizona, 2000, Huntoon P. W. ,
Most of the ground water in the Grand Canyon region circulates to springs in the canyon through the thick, deeply buried, karstified Cambrian-Mississippian carbonate section. These rocks are collectively called the lower Paleozoic carbonates and comprise the Redwall-Muav aquifer where saturated. The morphologies of the caves in the Grand Canyon are primarily a function of whether the carbonates are unconfined or confined, a distinction that has broad significance for ground-water exploration and which appears to be generally transferable to other carbonate regions. Caves in unconfined high-gradient environments tend to be highly localized, partially saturated, simple tubes, whereas those in confined low-gradient settings are saturated 2- or even 3-dimensional mazes. The highly heterogeneous, widely spaced conduits in the unconfined settings make for difficult drilling targets, whereas the more ubiquitously distributed mazes in confined settings are far easier to target. The distinctions between the storage characteristics within the two classes are more important. There is minimal ground-water storage in the unconfined systems because cave passages tend to be more widely spaced and are partially drained. In contrast, there is maximum storage in the saturated mazes in the confined systems. Consequently, system responses to major storm recharge events in the unconfined systems are characterized by flow-through hydraulics. Spring discharge from the unconfined systems tends to be both flashy and highly variable from season to season, but total dissolved solids are small. In contrast, the pulse-through hydraulics in the artesian systems cause fluctuations in spring discharge to be highly moderated and, in the larger basins, remarkably steady. Both total dissolved solids and temperatures in the waters from the confined aquifers tend to be elevated because most of the water is derived from storage. The large artesian systems that drain to the Grand Canyon derive water from areally extensive, deep basins where the water has been geothermally heated somewhat above mean ambient air temperatures. Karst permeability is created by the flow system, so dissolution permeability develops most rapidly in those volumes of carbonate aquifers where flow concentrates. Predicting where the permeability should be best developed in a carbonate section involves determining where flow has been concentrated in the geologic past by examining the geometry and hydraulic boundary conditions of the flow field. Karstification can be expected to maximize in those locations provided enough geologic time has elapsed to allow dissolution to adjust to the imposed boundary conditions. The rate of adjustment in the Grand Canyon region appears to be related to the degree of saturation. The artesian systems are far better adjusted to hydraulic gradients than the unconfined systems, a finding that probably implies that there is greater contact between the solvent and rock in the saturated systems. These findings are not arcane distinctions. Rather, successful exploration for ground water and management of the resource is materially improved by recognition of the differences between the types of karst present. For example, the unsaturated conduit karsts in the uplifts make for highly localized, high risk drilling targets and involve aquifers with very limited storage. The conduits have highly variable flow rates, but they carry good quality water largely derived from seasonal flow-through from the surface areas drained. In contrast, the saturated basin karsts, with more ubiquitous dissolutional permeability enhancement, provide areally extensive low risk drilling targets with large ground-water storage. The ground water in these settings is generally of lesser quality because it is derived mostly from long term storage

Nang Nuan oil field, B6/27, Gulf of Thailand: karst reservoirs of meteoric or deep-burial origin?, 2000, Heward A. P. , Chuenbunchom S. , Makel G. , Marsland D. , Spring L. ,
Karst reservoirs in the Chumphon Basin of the Gulf of Thailand have produced oil at well rates exceeding 10 000 BBL/d. Meteorically karstified buried hills were recognized as a potential exploration play. The Nang Nuan discovery well appeared to confirm such a play, and the concept prevailed despite the accumulation of contrary and unusual data. By the time a subsequent well had produced nearly 4 x 10(6) BBL oil, there was a desire to better understand the prospectivity of the concession. The accumulated data indicate that the highs are probably syn-rift horsts and inversion features. Karst reservoirs occur in Ratburi carbonates, and Mesozoic and Tertiary clastics, apparently unrelated to subaerial exposure. The karstification appears to be primarily of deep-burial origin, as indicated by the nature of the karst, substantial pore volumes that are difficult to account for, and temperature and flow anomalies consistent with active geothermal circulation. There are granites and hot springs in the vicinity, and abundant CO2 in this and neighbouring basins. Such deep-burial karst reservoirs have different implications for reserves estimation, prospect ranking and well completions

Spatial patterns of diagenesis during geothermal circulation in carbonate platforms., 2001, Wilson A. M. , Sanford W. , Whitaker F. , Smart P.

Weichselian palaeoclimate and palaeoenvironment in Europe: background for palaeogroundwater formation, 2001, Vaikmae R. , Edmunds W. M. , Manzano M. ,
A review is given of palaeoclimatic and palaeoenvironmental evidence across Europe for the Weichselian period relevant to interpreting the emplacement and circulation of groundwaters. In addition, this provides the background against which the evidence of past climates and environments contained in groundwaters in coastal areas of Europe, from the Baltic to the Atlantic Ocean may be compared. For much of the Weichselian, although significantly colder than at present, conditions were favourable for the recharge of groundwater, as shown, for example, by periods of speleothem growth. During the last glacial maximum (LGM) recharge is likely to have ceased over much of permafrost-covered Europe, although shallow groundwater recharge from meltwater (generated by the geothermal gradients) could have taken place beneath the ice where pressure relief through tunnel valleys may have occurred. Modern recharge could have started as early as 13 14C ka BP, but probably interrupted by the Younger Dryas between 11 and 10 14C ka BP. In the Baltic areas, ice-dammed lakes inhibited the start of the modern hydrogeological regimes until c. 10.3 14C ka BP. Tundra conditions prevailed over most of ice-free southern Europe at the time of the LGM. At this time the area south of the Portuguese-Spanish border retained a generally warm and relatively humid climate due to the maintenance of warmer sea-surface temperatures derived from Atlantic Ocean circulation. For most of coastal Europe, however, the most significant impact on groundwater circulation is likely to have been the lowering of sea levels that drained large areas of the shelf, such as the North Sea and the English Channel, and also had a significant impact on the Atlantic coast of the Iberian Peninsula where the maximum lowering of up to 130 m would have been experienced. This, together with the general changes in climate, would also have reorganized the atmospheric chemistry over sites in Europe that is likely to be recorded in the groundwater's chemical and isotopic signatures

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