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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 ponor is (slavic.) 1. hole or opening in the bottom or side of a depression where a surface stream or lake flows either partially or completely underground into the karst ground-water system. a seaponor is where sea-water flows or is drawn into an opening by a vacuum in karstified rock [20]. 2. hole in the bottom or side of a closed depression through which water passes to or from an underground channel [10]. synonyms: (british.) swallet, swallow hole, stream sink; (french.) ponor, aven, gouffre, perte; (german.) schlund, saugloch, schlinger, ponor; (greek.) katavothra; (italian.) inghittitoio, capovento; (russian.) ponor; (spanish.) sumidero, ponor, perdida; (turkish.) su yutan; (yugoslavian.) ponor, utok, poziralnik, pivka. see also swallow hole.?

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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 16 to 30 of 74
Depth of conduit flow in unconfined carbonate aquifers, 2001, Worthington Stephen R. H. ,
The locus of formation of cave conduits in carbonate aquifers is dependent on hydraulic, structural, and solubility factors, and these can facilitate flow deep below the water table. Geothermal heating results in increasing temperatures and decreasing viscosity with depth. This favors deep conduit development for flow paths with lengths >3 km. Steeply dipping strata aid the flow of undersaturated water to depth along bedding planes. These factors indicate that flow deep below the water table should be associated with steep dips and long flow paths. Empirical evidence strongly supports this model and demonstrates that the flow depth of conduits is directly proportional to flow-path length and stratal dip

Hydrochemistry of the Cesme geothermal area in western Turkey, 2001, Gemici U, Filiz S,
Hydrochemical characterization of thermal waters discharged from springs and wells in the Cesme geothermal area show that there are two groups. One is of thermal waters from a lower aquifer composed of Triassic karst limestones, which are the main potential reservoir of the area. They are of Na-Cl type and between 37 and 62degreesC and have total dissolved solids (TDS) with around 35 000 mg/l. The other group are thermal waters derived from an upper aquifer formed by Neogene terrestrial sediments. These have lower discharge temperatures (37-40degreesC) and lower TDS values due to their having mixed with local groundwater before emerging. The isotopic and chemical data shows that the initial aqueous solution is a mixture of modern seawater and meteoric water in various proportions. Enrichment in delta(18)O and deltaD values and tritium contents (8 1 TU) of thermal waters reflect a rapid circulation and the contribution of modern seawater. The thermal waters are undersaturated with respect to gypsum but oversaturated, or around equilibrium, with respect to dolomite and calcite. Several chemical geothermometry techniques applied to Cesme geothermal waters gave estimated reservoir temperatures of around 85-100degreesC. (C) 2001 Elsevier Science B.V. All rights reserved

Miocene phreatomagmatic volcanism at Tihany (Pannonian Basin, Hungary), 2001, Nemeth K. , Martin U. , Harangi S. ,
A late Miocene (7.56 Ma) maar volcanic complex (Tihany Maar Volcanic Complex - TMVC) is preserved in the Pannonian Basin and is part of the Bakony-Balaton Highland Volcanic Field. Base surge and fallout deposits were formed around maars by phreatomagmatic explosions, caused by interactions between water-saturated sediments and alkali basalt magma carrying peridotite Iherzolite xenoliths as well as pyroxene and olivine megacrysts. Subsequently, nested maars functioned as a sediment trap where deposition built up Gilbert-type delta sequences. At the onset of eruption, magma began to interact with a moderate amount of groundwater in the water-saturated sand. As eruption continued phreatomagmatic blasts excavated downward into limestones, providing access to abundant karst water and deeper to sandstones and schist both providing large amount of fracture-filling water, At the surface, this 'wet' eruption led to the emplacement of massive tuff breccias by fall, surge, mudflow and gravity flow deposition. The nature of the TMVC maar eruptions and their deposits appears to depend on the hydrological condition of the karst and/or fracture-filling aquifer, which varies seasonally with rainfall and spring runoff. The West and East Maar volcanoes of TMVC are interpreted to represent low water input from the karst and/or fracture-filling aquifer ('summer vent'), whereas the East Maar is interpreted to have formed when abundant karst and/or fracture-filling water was available ('spring vent'). (C) 2001 Elsevier Science B.V. All rights reserved

A conceptual model of the Tianjin geothermal system based on isotopic studies, 2001, Wang K. , Zhu J. L. ,
The isotopic technique is an effective measure to set up the conceptual model of a hydrothermal system. A deep circular geothermal system exists in Tianjin, including the semi-open and semi-closed karst geothermal subsystem in the bedrock and closed porous water subsystem in the clastic rocks. The geothermal water is originated from the ancient precipitation of 21-10 kaBP. Since Holocene epoch, the geothermal water is sealed for heating up. The mainly feeding channels are the karst conduits in weathered carbonate rocks of Proterozoic and Lower Paleozoic

Pamukkale (Hirapolis) : un site de travertins hydrothermaux exceptionnel de Turquie, 2002, Nicod, Jean
Pamukkale (Hierapolis): An outstanding site of hydrothermal travertines in Turkey - These travertines result from the deposit of carbonates near the hydrothermal springs, on the main active fault zone on the northern border of the Denizli basin (W Turkey). Their high mineralised water, rich of CO2 of geothermal origin, accumulate limestone in the fissure ridges and in the cascades on the front of the old travertines balcony, building up in it flowstone and rimstone dams. This site is particularly important as much for the archaeological and palaeoenvironmental researches as the palaeoseismic and neotectonics regional data.

Modeling research in low-medium temperature geothermal field, Tianjin, 2002, Wang K. , Li C. H. ,
The geothermal reservoir in Tianjin can be divided into two parts: the upper one is the porous medium reservoir in the Tertiary system; the lower one includes the basement reservoir in Lower Paleozoic and Middle-Upper Proterozoic. Hot springs are exposed in the northern mountain and confined geothermal water is imbedded in the southern plain. The geothermal reservoir is incised by several fractures. In recent years, TIDS of the geothermal water have gone up along with the production rate increasing, along the eastern fracture zone (Cangdong Fracture and West Baitangkou Fracture). This means that the northern fracture system is the main seepage channel of the deep circulation geothermal water, and the reservoir has good connection in a certain area and definite direction. The isotopic research about hydrogen and carbon chronology indicates that the main recharge period of geothermal water is the Holocene Epoch, the pluvial and chilly period of 20 kaBP. The karst conduits in weathered carbonate rocks of the Proterozoic and Lower Paleozoic and the northeast regional fracture system are the main feeding channels of Tianjin geothermal water. Since the Holocene epoch, the geothermal water stayed at a sealed warm period. The tracer test in WR45 doublet system shows that the tracer test is a very effective measure for understanding the reservoir's transport nature and predicting the cooling time and transport velocity during the reinjection. 3-D numerical simulation shows that if the reinjection well keeps a suitable distance from the production well, reinjection will be a highly effective measure to extract more thermal energy from the rock matrix. The cooling of the production well will not be a problem

Karstification and Groundwater Flow, 2003, Kiraly, L.

One of the principal aims of hydrogeology is to propose a reasonably adequate reconstruction of the groundwater flow field, in space and in time, for a given aquifer. For example, interpretation of the chemical and isotopic composition of groundwater, understanding of the geothermal conditions (anomalies) or forecasting the possible effects of industrial waste disposals and of intensive exploitation nearly always would require the knowledge of the regional and/or local groundwater flow systems such as defined by Toth (1963). The problem of estimating the groundwater flow field in fractured and karstified aquifers is approached within the framework of a conceptual diagram showing the relationship between groundwater flow, hydraulic parameters (aquifer properties and boundary conditions), distribution of voids and geological factors.
Autoregulation between groundwater flow and karst aquifer properties, duality of karst, nested model of geological discontinuities, scale effect on hydraulic parameters and use of numerical finite element models to check the interpretation of the global response of karst springs are some of the subjects addressed by the author. Inferences on groundwater flow regime with respect to the stage of karst evolution can be made only if the hydraulic parameter fields and the boundary conditions are known by direct observations, or estimated by indirect methods for the different types of karst. Practical considerations on the monitoring strategies applied for karst aquifers, and on the interpretation of the global response obtained at karst springs will complete the paper, which throughout reflects the point of view of a hydrogeologist.


Le flux gothermique avec circulation deau profonde dans les karsts : la surprise des transitoires, 2004, Lismonde, Baudouin
Geothermal flux with deep karstic waters: surprise with transitory phenomena - After a recall of some generalities about geothermal flux and its origin, the effect of deep karstic water on the temperatures in karstic areas is analysed. Under conditions of a constant flow, two properties are well known: decreasing of geothermal flux in the karstic area; convergence of flux lines in the neighbourhood of collector. The surprise occurs about the transitory phenomena: greater the depth of the subterranean river, greater and faster the amplitude of thermal perturbation. Indeed, when some galleries completely dry up, the heat flow from the rock can warm up the galleries by tenths of a degree in few weeks. This is in contradiction with the idea of permanent deep temperatures.

Temperature distribution in karst systems: the role of air and water fluxes, 2004, Luetscher M. , Jeannin P. Y.

A better understanding of heat fluxes and temperature distribution in continental rocks is of great importance for many engineering aspects (tunnelling, mining, geothermal research,…). This paper aims at providing a conceptual model of temperature distribution in karst environments which display thermal “anomalies” when compared to other rocks.
In temperate regions, water circulations are usually high enough to completely “drain out” the geothermal heat flux at the bottom of karst systems (phreatic zone). A theoretical approach based on temperature measurements carried out in deep caves and boreholes demonstrates however that air circulations can largely dominate water infiltrations in the karst vadose zone, which can be as thick as 2000 m. Consequently, temperature gradients within this zone are similar to the lapse rate of humid air (~0.5°C/100 m). Yet, this value depends on the regional climatic context and might present some significant variations.


Cave temperatures and global climatic change., 2004, Badino Giovanni
The physical processes that establish the cave temperature are briefly discussed, showing that cave temperature is generally strictly connected with the external climate. The Global Climatic changes can then influence also the underground climate. It is shown that the mountain thermal inertia causes a delay between the two climates and then a thermal unbalance between the cave and the atmosphere. As a consequence there is a net energy flux from the atmosphere to the mountain, larger than the geothermal one, which is deposited mainly in the epidermal parts of caves.

La scheresse 2003 et les mesures de temprature au Trou qui Souffle de Maudre : rle du flux gothermique, 2005, Lismonde, Baudouin
The dryness of 2003 and the temperature measurements in the Trou qui Souffle (Maudre, France): role of the geothermal flux - A deep passage in the Trou qui Souffle (Vercors, France) was equipped with a Luirographe that allows to record continuously the variations in both water level and temperature. The results show that the dryness of 2003 induced an air temperature rise of 1C. In autumn and winter 2003-2004, several floods were recorded which were coupled with a decrease in temperature. These measurements allowed to evidence thermal heterogenities within the massif. We attribute these to the geothermal flux. A theoretical model (published in a previous article) provides an interpretation of the observed phenomena: the geothermal flux is focalised, thus the change of temperature in that deep level is very rapid.

Hydraulic and geological factors influencing conduit flow depth, 2005, Worthington, S. R. H.

There has much been speculation as to whether cave formation should occur at, above, or below the water table, but a satisfactory explanation has been lacking until recently. The last 50 years has seen extensive mapping of caves both above and, more recently, below the water table. It is now becoming apparent that there are systematic differences in depth of flow between different areas and that conduit flow to depths >100m below the water table is not uncommon. Such deep flow is facilitated by the lower viscosity of geothermally heated water at depth. Analysis of data from caves shows that depth of flow is primarily a function of flow path length, stratal dip and fracture anisotropy. This explains why conduits form at shallow depths in platform settings such as in Kentucky, at moderate depths (10–100m) in folded strata such as in England and in the Appalachian Mountains, and at depths of several hundred metres in exceptional settings where there are very long flow paths.


'Sour gas' hydrothermal jarosite: ancient to modem acid-sulfate mineralization in the southern Rio Grande Rift, 2005, Lueth V. W. , Rye R. O. , Peters L. ,
As many as 29 mining districts along the Rio Grande Rift in southern New Mexico contain Rio Grande Rift-type (RGR) deposits consisting of fluorite-barite sulfide-jarosite, and additional RGR deposits occur to the south in the Basin and Range province near Chihuahua, Mexico. Jarosite occurs in many of these deposits as a late-stage hydrothermal mineral coprecipitated with fluorite, or in veinlets that crosscut barite. In these deposits, many of which are limestone-hosted, jarosite is followed by natrojarosite and is nested within silicified or argillized wallrock and a sequence of fluorite-barite sulfide and late hematite-gypsum. These deposits range in age from similar to 10 to 0.4 Ma on the basis of Ar-40/Ar-39 dating of jarosite. There is a crude north-south distribution of ages, with older deposits concentrated toward the south. Recent deposits also occur in the south, but are confined to the central axis of the rift and are associated with modem geothermal systems. The duration of hydrothermal jarosite mineralization in one of the deposits was approximately 1.0 my. Most Delta(18)O(SO4)-OH values indicate that jarosite precipitated between 80 and 240 degrees C, which is consistent with the range of filling temperatures of fluid inclusions in late fluorite throughout the rift, and in jarosite (180 degrees C) from Pena Blanca, Chihuahua, Mexico. These temperatures, along with mineral occurrence, require that the jarosite have had a hydrothermal origin in a shallow steam-heated environment wherein the low pH necessary for the precipitation of jarosite was achieved by the oxidation of H2S derived from deeper hydrothermal fluids. The jarosite also has high trace-element contents (notably As and F), and the jarosite parental fluids have calculated isotopic signatures similar to those of modem geothermal waters along the southern rift; isotopic values range from those typical of meteoric water to those of deep brine that has been shown to form from the dissolution of Permian evaporite by deeply circulating meteoric water. Jarosite delta(34)S values range from -24 parts per thousand to 5 parts per thousand, overlapping the values for barite and gypsum at the high end of the range and for sulfides at the low end. Most delta(34)S values for barite are 10.6 parts per thousand to 13.1 parts per thousand and many delta(34)S values for gypsum range from 13.1 parts per thousand to 13.9 parts per thousand indicating that a component of aqueous sulfate was derived from Permian evaporites (delta(34)S = 12 2 parts per thousand). The requisite H2SO4 for jarosite formation was derived from oxidation of H2S which was likely largely sour gas derived from the thermochemical reduction of Permian sulfate. The low delta(34)S values for the precursor H2S probably resulted from exchange deeper in the basin with the more abundant Permian SO42-- at similar to 150 to 200 degrees C. Jarosite formed at shallow levels after the PH buffering capacity of the host rock (typically limestone) was neutralized by precipitation of earlier minerals. Some limestone-hosted deposits contain caves that may have been caused by the low pH of the deep basin fluids due to the addition of deep-seated HF and other magmatic gases during periods of renewed rifting. Caves in other deposits may be due to sulfuric acid speleogenesis as a result of H2S incursion into oxygenated groundwaters. The isotopic data in these 'sour gas' jarosite occurrences encode a recod of episodic tectonic or hydrologic processes that have operated in the rift over the last 10 my. (c) 2004 Elsevier B.V. All rights reserved

The geochemistry of fluids from an active shallow submarine hydrothermal system: Milos island, Hellenic Volcanic Arc, 2005, Valsamijones E. , Baltatzis E. , Bailey E. H. , Boyce A. J. , Alexander J. L. , Magganas A. , Anderson L. , Waldron S. , Ragnarsdottir K. V. ,
Geothermal activity in the Aegean island of Milos (Greece), associated with island-arc volcanism, is abundant both on-and off-shore. Hydrothermal fluids venting from several sites, mainly shallow submarine (up to 10 m), but also just above seawater level in one locality, were sampled over four summer field seasons. Some of the discharging fluids are associated with the formation of hydrothermal edifices. Overall, the main characteristics of the hydrothermal fluids are low pH and variable chlorinity. The lowest recorded pH was 1.7, and chlorinity ranged from 0.1 to 2.5 times that of seawater. The highest fluid temperatures recorded on site were 115 degrees C. Two main types of fluids were identified: low-chlorinity fluids containing low concentrations of alkalis (potassium, lithium, sodium) and calcium, and high concentrations of silica and sulphate; and high-chlorinity fluids containing high concentrations of alkalis and calcium, and lower concentrations of silica and sulphate. The type locality of the high-chlorinity fluids is shallow submarine in Palaeochori, near the cast end of the south coast of the island, whereas the type locality of the low-chlorinity fluids is a cave to the west of Palaeochori. The two fluid types are therefore often referred to as 'submarine' and 'cave' fluids respectively. Both fluid types had low magnesium and high metal concentrations but were otherwise consistently different from each other. The low-chlorinity fluids had the highest cobalt, nickel, aluminium, iron and chromium (up to 1.6 mu M, 3.6 mu M, 1586 mu M, 936 mu M and 3.0 mu M, respectively) and the high-chlorinity fluids had the highest zinc, cadmium, manganese and lead (up to 4.1 mu M, 1.0 mu M, 230 mu M and 32 mu M, respectively). Geochemical modelling suggests that metals in the former are likely to have been transported as sulphate species or free ions and in the latter as chloride species or free ions. Isotopic values for both water types range between delta D -12 to 33 parts per thousand and delta(18)O 1.2 to 4.6 parts per thousand. The range of fluid compositions and isotopic contents indicates a complex history of evolution for the system. Both types of fluids appear to be derived from seawater and thus are likely to represent end members of a single fluid phase that underwent phase separation at depth. Crown Copyright (c) 2005 Published by Elsevier B.V. All rights reserved

Underground drainage systems and geothermal flux, 2005, Badino, G.
The paper presents an analysis of the interaction between the geothermal flux and the water or air- deep drainage networks. The problem of geothermal power intercepted by deep structures and, in general, the temperature field calculations, is converted to classical thermo-engineering problems in terms of shape factors. It is shown that the fluid flow in a conduit perturbs the whole deep rock temperature field until the geothermal flux of a large area is focalised onto the conduit. It is shown that either small water masses flowing into a mountain are able to perturb the rock temperature up to the surface, on sizes that do not depend on water mass dimension, but on its depth, and then on enormous volumes. The introduction of the geothermal cross section of an underground drainage structure allows us to improve the classical formula of minimum provenance depth of geothermal water. Enlarging factors are applied to the classical estimation in dependence of the ratio between the actual average discharge and the critical discharge Qc, which depends on the conduit geothermal cross section. The geothermal umbra cones created in the overlying rock by deep underground structures are described. It is shown that the geothermal flux can play a significant role in the underground drainage phenomenology.

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