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Enviroscan Ukrainian Institute of Speleology and Karstology

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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 loosest packing is the three-dimensional arrangement of particles with the highest possible void volume per unit cell [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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What is Karstbase?



Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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;
See all featured articles from other geoscience journals

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Your search for circulation (Keyword) returned 184 results for the whole karstbase:
Showing 166 to 180 of 184
Speleogenetic effects of interaction between deeply derived fracture-conduit and intrastratal matrix flow in hypogene karst settings, 2012,
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Klimchouk A. B. , Tymokhina E. I. , Amelichev G. N.

In carbonate rocks, especially in those with high primary porosity such as most Cenozoic carbonates, the interaction between deeply derived rising flow through sub-vertical fracture-controlled conduits and intrastratal matrix flow of shallower systems can invoke mixing corrosion and result in prominent speleogenetic effects. This paper outlines a conceptual model of such interaction and provides instructive field examples of relevant morphological effects from two different regions within the Prichernomorsky (north Black Sea) basin, where karst features are developed in lower Pliocene, Eocene and Paleocene limestones. In the Crimean fore-mountain region, extensive steep to vertical limestone scarps formed through recent exposure of hypogenic fracture-controlled conduits provide outstanding possibilities to directly examine details of the original karstic porosity. The morphological effects of the conduit/matrix interaction, documented in both caves and exposed scarps, include lateral widening of sub-vertical conduits within the interaction intervals (formation of lateral notches and niches) and the development of side bedding-parallel conduits, pockets and vuggy-spongework zones. Natural convection circulation, invoked by interaction of the two flow systems, spreads the morphological effects throughout the conduit space above the interaction interval. Where the interaction of the two flow systems is particularly strongly localized, such as along junctions of two vertical fracture sets, the resultant morphological effect can take the form of isolated chambers. The variety of speleogenetic features developed through the conduit/matrix interaction, can be broadly grouped into two categories: 1) variously shaped swells of the major fracture conduit itself (morphological features of its walls – niches and pockets), and 2) features of the vuggy-spongework halo surrounding the conduit. This halo includes clustered and stratiform cavities, spongework zones and lateral side conduits. The speleogenetic features due to conduit/matrix flow interaction, especially the halo forms, often demonstrate distinct asymmetry between opposite walls of the conduits. The prominent phenomenon of the vuggy-spongework halo around fracture-controlled conduits has important hydrogeological implications. A comparison of karst features in different regions and rock formations clearly shows that in spite of some distinctions imposed by local structural, sedimentological and paleo-hydrogeological peculiarities, hypogenic speleoforms in limestones of different age and of different degree of diagenetic maturity demonstrate remarkable similarities.

Petrographic and isotopic evidence for late-stage processes in sulfuric acid caves of the Guadalupe Mountains, New Mexico, USA, 2012,
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Palmer Margaret, Palmer Arthur N.

Caves of the Guadalupe Mountains have experienced many modifications since their final phase of sulfuric acid speleogenesis several million years ago. Petrographic and geochemical data reveal details of the change from H2SO4 to CO2-dominated reactions. The H2SO4 dissolution front acquired a coating of replacement gypsum with local pockets of anhydrite and by-products of altered clay, including Fe-Mn oxides. Alteration of bedrock beneath the gypsum produced a white micritized rind with small negative shifts in δ13C and δ18O. Solution basins contain records of the earliest post-speleogenetic processes: corroded bedrock, residual anhydrite, Fe-Mn oxides from fluctuating pH and Eh, mammillary calcite, and dolomitization. Later meteoric water removed or recrystallized much of the gypsum and early micrite, and replaced some gypsum with calcite. Mammillary crusts demonstrate fluctuating groundwater, with calcite layers interrupted by films of Fe-Mn oxides precipitated during periodic inflow of anoxic water. Condensation moisture (from local evaporation) absorbs CO2 from cave air, corroding earlier features and lowering their δ13C and δ18O. Drips of condensation water deposit minerals mainly by evaporation, which increases δ18O in the speleothems while δ13C remains nearly constant. By forcing calcite precipitation, evaporation raises the Mg content of remaining water and subsequent precipitates. Dolomite (both primary and replacive) is abundant. In areas of low air circulation, water on and within carbonate speleothems equilibrates with cave-air CO2, causing minerals to recrystallize with glassy textures. Fluorite on young evaporative speleothems suggests a recent release of deep-source HF gas and absorption by droplets of condensation water. 

Piezometric and hydrogeochemical characterization of groundwater circulation in complex karst aquifers. A case study: the Mancha Real-Pegalajar aquifer (Southern Spain), 2012,
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Gonzalezramon A. , Lopezchicano M. , Rubiocampos J. C.

A small karst aquifer of great structural complexity has been subjected to significant resource withdrawal over recent decades. This exploitation aroused social conflict due to the effect it has had on emblematic springs. This research has analysed piezometric data collected over the course of 12 years and the spatial hydrochemical data supplied by the main water points associated with it. The spatial and temporal evolution of the main chemical species in the groundwater and the hydrogeochemical processes affecting them have been studied, modelling them with the programme PHREEQC. These data suggest a complicated model of hydrogeological function with sectors storing water at different depths and connected to each other locally as determined by the geological structure.


Hypogene karst of the eastern part of the Crimean fore-mountains, 2012,
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Klimchouk A. B. , Amelichev G. M. , Tymokhina . . , Tokarev S. V.

Carbonate rocks of upper Cretaceous, Paleocene and Eocene crop out in cuesta escarpments in different sectors of the eastern part of the Inner Range of the Crimean fore-mountains. Scarps and adjacent strips of the plateaus demonstrate a set of features, characteristic and unique for the Crimean fore-mountain region, represented by various conduit and cavernous forms (karstified fractures, grottoes, niches, caves, vugs and zones of vuggy porosity), sculptured surfaces and honeycomb, boxwork and spongework surfaces of scarps, and also by couloirs and blind valleys in the near-scarp strips of structural slopes. The paper demonstrates that all these forms are relics of the morphology of sub-vertical hypogenic rift-like conduits, their meso-elements and forms of the vuggy fringe, exposed due to the scarp retreat by block toppling. Previous ideas of the formation of grottoes and niches in scarps by processes of external weathering and gravitational destruction are shown to be inadequate, and the hypogenic karst origin of these forms is firmly established. The analysis of distribution and morphology of relict hypogenic karst features has allowed reconstructing the structure and functioning of hypogenic karst systems, which had been formed by dissolution and metasomatic alteration of host rocks under confined conditions, along cross-formational tectonic fractures organized in linear corridors and clusters. Interaction of rising fracture-vein waters of the deep circulation system with intra- and interstratal waters of shallower systems played a particular role in hypogenic speleogenesis. It is shown that hypogenic karst was one of the primary factors of regional geomorphic development as it determined locations and morphology of the cuesta escarpments, as well as further landform development in the adjacent areas of the structural surfaces.

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Bella Pavel, Bosak Pavel

The most conspicuous six examples illustrating ascending (perascensum) speleogenesis linked with deep faults/fault systemswere selected from Slovakia and Czech Republic. In the past,the caves have been described as product of phreatic, epiphreaticand vadose speleogenesis related to the evolution of localwater courses and valley incision, and linked mostly with Pleistocenegeomorphic evolution. Our analysis illustrates severalcommon characteristics of caves: (1) they developed along or inclose vicinity of deep faults/fault zones, commonly of regionalimportance; (2) the groundwater ascended due to deep faults/fault systems mostly as results of deep regional circulation ofmeteoric waters from adjacent karst or nonkarst areas; (3) the3D mazes and labyrinths dominate in cave morphology; (4)speleogens (e.g., cupolas, slots, ceiling channels, spongework,rugged phreatic morphology especially along slots) indicateascending speleogenesis in deep phreatic to phreatic environments;(5) they exhibit poor relation to the present landscape;in some of them fluvial sediments are completely missing inspite of surface rivers/streams in the direct vicinity; (6) strongepiphreatic re-modelling is common in general (e.g., subhorizontalpassages arranged in cave levels, water-table flat ceilingsand notches) and related to the evolution of the recent landscape;(7) recharge structures and correlate surface precipitatesare poorly preserved or completely missing (denuded) on thepresent surface in spite of fact that recent recharges broadlyprecipitate travertines; (8) caves can be, and some of them are,substantially older than the recent landscape (Pliocene, Miocene),and (9) caves were formed in conditions of slow water ascent, which differentiate the process from faster vauclusianascending speleogenetical models. Any of described caves containsclear diagnostic features of real hypogene caves. There aremissing evidences that at least heated groundwaters took partduring speleogenesis of studied caves, nevertheless, somewhatincreased water temperature can be expected during speleogenesisat least in some of caves. Any of described caves cannotbe directly characterized as product of thermal waters or hydrothermalprocess (i.e. as real hyperkarst sensu Cigna 1978),therefore they do not represent hypogenic caves.

Evolution of Intrastratal Karst and Caves in Gypsum, 2013,
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Klimchouk, A. B.

The term ‘intrastratal karst’ denotes a series of evolutionary karst types corresponding to successive stages of karst developmentin a soluble rock while it moves back to exposure after being buried by younger strata. The major boundaryconditions, the overall circulation pattern, and extrinsic factors and intrinsic mechanisms of karst development appear tochange considerably between the stages, resulting in characteristic styles of cave development and surface karst morphology,particularly distinct in case of gypsum karst.As gypsum is much more soluble than carbonates, it does not survive long in outcrops beyond arid areas. Wheregypsum is exposed to the surface with no substantial karstification formed during various stages of reburial, the developmentof epigene solution porosity in this rock is hindered due to the fast dissolution, being limited to flow paths in whichthe breakthrough conditions can be attained quickly. However, karst processes in gypsum develop extensively in intrastratalkarst settings, with inheritance from the deep-seated stage through the denuded one. Karstification may commence in anystage of intrastratal development, and during the next successive stage, the process, although in changed conditions, will beaffected significantly by the preformed solution porosity. Speleogenesis in deep-seated gypsum karst is exclusively hypogene.In subjacent karst, both hypogene and epigene speleogenesis may operate depending on the locally prevailing flowregime, but hypogene speleogenesis still dominates. In entrenched and denuded karst types, speleogenesis is overwhelminglyepigenic, but it is greatly facilitated by the presence of solution porosity inherited from the previous stages.Diverse and expressive karst landforms related to subsurface conduits evolve through different stages of the intrastratal karstdevelopment.The subsidence hazard in regions underlain by gypsum differs substantially between the karst types, so that one canobtain a kind of integrated general hazard assessment by classifying a given individual karst according to its evolution state.In general, various types of intrastratal karst, subjacent karst in particular, are the most potent in generating subsidence problems, whereas exposed karst types, particularly open karst, are the least prone to subsidence

Isotopic and hydrochemical data as indicators of recharge areas, flow paths and waterrock interaction in the Caldas da RainhaQuinta das Janelas thermomineral carbonate rock aquif, 2013,
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Marques J. M. , Graa H. , Eggenkamp H. G. M. , Neves O. , Carreira P. M. , Matias M. J. , Mayer B. , Nunes D. , Trancoso V. N.

An updated conceptual circulation model for the Caldas da Rainha and Quinta das Janelas thermomineralwaters was developed. These thermomineral waters (T _ 33 _C) are related to a huge syncline ascribed tothe regional flow paths. Two diapiric structures were responsible for the uplift and subsequent folding ofregional Jurassic carbonate rocks. Environmental isotopic (d2H and d18O) data indicates that the mainrecharge area of the thermomineral system is linked to the Jurassic limestones (Candeeiros Mountains,E border of the syncline). The thermomineral waters belong to the Cl–Na sulphurous-type, with a totalmineralization of about 3000 mg/L. The thermomineral aquifer system seems to be ‘‘isolated’’ fromanthropogenic contamination, which is typical for the local shallow groundwater systems, due to theexistence of impermeable layers composed of a series of loamy and detritic rocks of the Upper Jurassic.The presence of 3H in some thermomineral borehole waters, not accompanied by an increase in SO2_4 andNO_3 , could be ascribed to different underground flow paths and different mean residence time. Thed34S(SO4) and d18O(SO4) values of dissolved sulphate of groundwaters of the Caldas da Rainha Spas indicatethat the sulphate is the result of water–rock interaction with evaporitic rocks (e.g. gypsum and anhydrite)ascribed to the regional synclinal structure.

Concentration and stable carbon isotopic composition of CO2 in cave air of Postojnska jama, Slovenia, 2013,
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Mandić, M. , Mihevc A. , Leis A, Krajcar Bronić, I.


Partial pressure of CO2 (pCO2) and its isotopic composition (δ13CairCO2) were measured in Postojnska jama, Slovenia, at 10 locations inside the cave and outside the cave during a one-year period. At all interior locations the pCO2 was higher and δ13CairCO2 lower than in the outside atmosphere. Strong seasonal fluctuations in both parameters were observed at locations deeper in the cave, which are isolated from the cave air circulation. By using a binary mixing model of two sources of CO2, one of them being the atmospheric CO2, we show that the excess of CO2 in the cave air has a δ13C value of -23.3 ± 0.7 ‰, in reasonable agreement with the previously measured soil-CO2 δ13C values. The stable isotope data suggest that soil CO2 is brought to the cave by drip water.

Hydrogeological approach to distinguishing hypogene speleogenesis settings, 2013,
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Klimchouk, A. B.

The hydrogeological approach to defining hypogene speleogenesis (HS) relates it to ascending groundwater flow (AF). HS develops where AF causes local disequilibria conditions favoring dissolution and supports them during sufficiently long time in course of the geodynamic and hydrogeological evolution. The disequilibrium conditions at depth are invoked by changing physical-chemical parameters along an AF paths, or/and by the interaction between circulation systems of different scales and hydrody-namic regimes. The association of HS with AF suggests a possibility to discern regulari-ties of development and distribution of HS from the perspectives of the regional hy-drogeological analysis. In mature artesian basins of the cratonic type, settings favorable for AF and HS, are as follows: 1) marginal areas of discharge of the groundwaters of the 2nd hydrogeological story (H-story), 2) zones of topography-controlled upward cir-culation within the internal basin area (at the 1st and, in places, at the 2nd H-stories; 3) crests of anticlinal folds or uplifted tectonic blocs within the internal basin area where the upper regional aquitard is thinned or partially breached; 4) linear-local zones of deep-rooted cross-formational faults conducting AF from internal deep sources across the upper H-stories. Hydrodynamics in the 3rd and 4th stories is dominated by ascending circulation strongly controlled by cross-formational tectonic structures. Specific circula-tion pattern develops in large Cenozoic carbonate platforms (the Florida-type), side-open to the ocean, where AF across stratified sequences in the coastal parts, driven by both topography-induced head gradients and density gradients, involves mixing with the seawater. The latter can be drawn into a platform at deep levels and rise in the plat-form interior (the Kohout’s scheme). In folded regions, AF and HS are tightly con-trolled by faults, especially those at junctions between large tectonic structures. In young intramontaine basins with dominating geostatic regime, HS is favored at margin-al discharge areas where circulation systems of different origins and regimes may inter-act, such as meteoric waters flows from adjacent uplifted massifs, basinal fluids expelled from the basin’s interiors, and endogenous fluids rising along deep-rooted faults. Spe-cific and very favorable settings for HS are found in regions of young volcanism with carbonate formations in a sedimentary cover

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Gą, Siorowski M. Hercman H.


Water circulation in Niedźwiedzia Cave system is complicated. The system is fed by direct infiltration of precipitation, infiltration from the surface stream and, possibly, by rising flow from deep sources. The cave is drained by system of karst springs in the Kleśnica stream valley, but some part of water flows across border ridge and occurs in Morava stream valley, Czech Republic (Ciężkowski et al. 2009). We tried to use tritium and stable isotopes to describe hydrology of the cave system and analyzed 155 water samples for stable isotopes and 38 water samples for tritium content. The Niedźwiedzia Cave system is composed of three levels of halls and galleries. In the upper level, stable isotope composition in drip water plots close to the local meteoritic water line (LMWL) on the δ18O vs δD diagram. It varies during the year similar to stable isotope composition of precipitation (i.e. low δ18O values during winters and higher δ18O during summers). The delay between isotopic signal in precipitation and drip water is ~10–14 days and this can be interpreted as a time of infiltration from the surface to the cave upper level. The correlation between isotopic composition of precipitation and drip water is not observed in the lower level of the cave system. There isotopic composition of drip water is more stable during the year. We use tritium dating method to estimate the age of this water. It has shown that infiltration time to the lower level is 1.4±0.3 year. The “oldest” water was found in karst spring draining the cave system. The estimated transit time is 3–4 years and suggest admixture of some “old” water that was not sampled in the cave.

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Simone Argiolas, Caddeo Guglielmo Angelo, Casu Lucilla, Muntoni Alberto, Papinuto Silvestro

Since many years cavers from different caving teams are carrying out a systematic study on the caves of Sulcis-Iglesiente, including geomorphological studies. Over thirty natural caves have been explored, surveyed and registered in the past few years, and over half of these have been made accessible by mine galleries. Among these are worth to be mentioned the “Tre Sorelle” of Domusnovas: these are three mine caves intercepted by the San Paolo mine tunnel. This tunnel, whose collapsed entrance has been reopened after a long digging campaign, has been explored and surveyed for around 700 meters. A total of 10 natural caves, mostly developed along fractures, have been explored and mapped, with developments ranging between 10 and 250 meters and depths from 15 to over 160 meters. Only two of these caves were previously known in the Regional Cave Register. In most of the caves, speleothems consist mainly of flowstones, some of which are clear or usually white, others are dark-brown or tending to black. Some samples of the first and the second flowstone types were collected respectively from the “Sesta Sorella” and “Seconda Sorella” Caves. The powders of these samples were analysed by an X-ray diffractometer. The first type consists of thicker layers of white and fibrous aragonite, which sometimes alternate with thinner layers of grey columnar calcite. In some samples, however, calcite interlayers were absent and just aragonite was found. The second type is composed of alternating layers of darkbrown hemimorphite. Some additional analyses were performed on these samples by Laser Ablation ICP-MS to determine the concentration of minor and trace elements in the different layers and mineralogical phases. The most abundant minor elements in calcite layers are Mg and Zn. Magnesium is about constant (~ 2000 ppm) on different spots and remains under the average Mg content of the cave calcite in this region, whereas Zn ranges from 103 to 104 ppm and is well above the Zn average in calcite of caves in the world. Barium concentration is about 80 ppm and more abundant than Pb (20 ppm) and Sr (10 ppm). Barium is also the main minor element in aragonite, where it can reach almost 2000 ppm. The Zn concentration is very high even in aragonite and is comparable to that of Sr (400-500 ppm), overcoming considerably the Pb concentration (20 ppm). In hemimorphite, the most abundant minor elements are Al and Fe (about 104 ppm). However, it was not quantified how much of these are in the hemimorphite lattice or come from some impurities. Actually, we notice that concentration of Fe and Al in the black layers of hemimorphite is an order of magnitude greater than in the brown ones. In addition, the black layers show an abrupt increase of Mn concentration, which overcomes Fe and Al. The evolution of these flowstones is most probably related to the circulation of fluids connected to the oxidation of sulphides, specially sphalerite.

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Dublyansky Yuri, Sptl Christoph

Bare Mountain is an isolated complex of mountain peaks Southeast of the town of Beatty in southern Nevada. This small mountain range is located between the alluvial basins of Crater Flat to the East and the northern Amargosa Desert to the Southwest. The range is built of a folded and complexly faulted, generally northward-dipping sequence of weakly to moderately metamorphosed upper Proterozoic and Paleozoic marine rocks. Along the eastern and northern margins of Bare Mountain there are four clusters of Ag-Hg-fluorite deposits from which pipe-like breccia bodies have been reported in the literature. One of these deposits, the Diamond Queen Mine (aka Goldspar Mine; 36°50.4’ N, 116°38.3’ W) was prospected for gold and mined for fluorspar. The age of the mineralization is younger than 12.9±0.4 Ma (according to K/Ar dates of replacement adularia). During our visit in 2010 we observed solutional cavities in the open-pit works of the mine carved in the dolomite of the Cambrian Nopah Formation. The cavities have dimensions of a few meters to tens of meters. Their inner surfaces are smooth and barren. The morphology of the cavities strongly suggests dissolution under phreatic conditions. Cavities are filled with buff-colored clay material containing bands of black to dark-violet to yellow- green to colorless fluorite. Fluid inclusions in the Diamond Queen fluorite yielded homogenization temperatures of ca. 130°C. We measured the δD of the fluid inclusion water in this fluorite and compared them to δD values measured in scalenohedral calcite from the Sterling Mine (Au) located 1.5 km to the north. Isotopic values are remarkably similar: δD = -100±2 ‰ (n = 6). Despite the fact that the analyzed water was derived from hypogene, hydrothermal minerals these isotopic values bear a paleoclimatological significance. This is because according to the currently accepted model, the Au-Hg-fluorite deposits at Bare Mountain owe their existence to the circulation of meteoric water triggered by emplacement of the silicic magma chamber under the Timber Mountain-Oasis Valley caldera some 15 km to the north. The Late Miocene meteoric- hydrothermal water is isotopically similar to the modern-day precipitation (-106 to -92 ‰). Between ca. 1.5 and 2.5 Ma the δD values of meteoric water in the area were substantially less negative (-70 to -50 ‰) and then gradually decreased to modern values. Knowledge regarding hypogene karst associated with the epithermal ore deposits in Nevada is limited. In north-central Nevada, post-ore hypogene dissolution, brecciation and mineralization occurred at some of the Carlin Trend deposits at ca. 2 Ma. In contrast, hypogene karst was a preore process at Diamond Queen; it has played a role in creating the ore-bearing structure.

Hypogene Speleogenesis, its hydrogeological significance and role in karst evolution (in Russian), 2013,
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Klimchouk A. B.

The book examines empirical and theoretical regularities of hypogene speleogenesis and reveals its hydrogeological significance and the role in karst evolution. It is demonstrated that hypogene karst, along with epigenic karst, is the fundamental and wide spread genetic variety of karst, which nature and peculiar features call for revision and refinement of some basic notions of the general karst paradigm. A new approach is advocated to a definition of the notion of karst, where the latter is viewed as a specific groundwater circulation system with key properties determined by speleogenesis.

It is shown that major distinctions in mechanisms of the development of karstic void-conduit structures (types of speleogenesis) are determined by hydrodynamic peculiarities of confined and unconfined groundwater systems, and by the circulation vector. An evolutionary classification of karst is elaborated, which main categories cumulatively reflect its origin and characterize its most essential properties. Hypogene karst is a natural stage in the evolution of karst groundwater circulation geosystems in the course of regressive lithogenesis and hydrogeological cycles.

The book reveals principal regional regularities and type settings of hypogene speleogenesis, and describes its functional, structural and morphological peculiar features. It demonstrates the significance of hypogene speleogenesis in the formation of hydrogenic deposits of mineral resources and hydrocarbons in soluble strata and adjacent formations, and its role in karst hazards. The genetic and evolutionary approach is outlined and advocated in dealing with karst-related applied issues of hydrogeology, geological engineering, petroleum and ore geology.

Hydrodynamic modeling of a complex karst-alluvial aquifer: case study of Prijedor Groundwater Source, Republic of Srpska, Bosnia and Herzegovina, 2013,
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Polomčić Dušan, Dragišić Veselin, Živanović Vladimir

Middle Triassic fractured and karstified limestone and dolomite form a karst aquifer in the Sana River Valley near the town of Prijedor. As a result of intensive tectonic movements, carbonate rocks are mostly below the Sana River level, covered by younger Pliocene and alluvial deposits. The main source of groundwater recharge is infiltration from the Sana River through its alluvium over most of the aquifer. The main objective of the research reported in this paper was to evaluate the hydraulic relationships of the alluvial, Pliocene and karst aquifers in order to better understand the water supply potential of the karst aquifer. Although the use of hydrodynamic modeling is not very common with karst aquifers, the developed model provided significant and useful information on the groundwater budget and recharge type. The influence of fault zones and spatial anisotropy of the karst aquifer were simulated on the hydrodynamic model by varying permeability on the xand y­axes of the Cartesian coordinate system with respect to the fault, the main pathway of groundwater circulation. Representative hydraulic conductivities were Kx

 = 2.3·10­3

 m/s and Ky

 = 5.0·10­3

 m/s in the faults of Nw to SE direction, and Kx

 = 2.5·10­3

 m/s and Ky


 m/s in the faults of Sw to NE trend. Model research showed that the karst aquifer can be used in the long term at maximal tested capacities and that current groundwater exploitation is not compromised in dry periods when the water budget depends entirely on recharge from the Sana River.

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Gradziński M. , Lewandowska A. , Paszkowski M. , Duliński M. , Nawrocki J. , Żywiecki M.

The development of caves influenced by the deep circulation of water has received increasing interest for the last thirty years. Presently, hypogene caves have been recognized all around the world. Conversely, the ancient examples filled with sediments and representing palaeokarst forms are not so common.
The karst forms and their sediment fillings were encountered in the Dębnik Anticline (Kraków region, Southern Poland) composed of Middle Devonian to Mississippian carbonates. The development of karst slightly postdates the Permian (ca. 300 Ma) volcanic activity in the Kraków region. In this region major transcontinental strike and slip Hamburg-Kraków-Dobruja fault zone induced a series of minor, en echelon, extensional faults, which served as magma passages and guided karst conduits.
The karst forms in the Dębnik Anticline reach several to tens of meters in size. They are filled with: i) massive, subaqueous, coarse crystalline calcite spar; ii) crystalloclastic, bedded limestones; iii) jasper lenses; iv) kaolinitised tuffs. The sediments are characterized by red colouration caused by iron compounds.
Coarse crystalline calcite spar composes beds up to several dozen centimeters in thickness. They are laminated and comprise frutexites type structures. The calcites are interbedded with pinkish-red crystalloclastic limestones, which are built of detritic calcite crystals from silt size to a few millimeters across. Some of the crystals are of skeletal type. Crystalloclastic limestones are normally graded. Both calcite spar and crystalloclastic limestones underwent synsedimentary deformations, which resulted in brecciation and plastic deformations.
The above deposits fill karst forms up to a few metres in lateral extent. However, analogously filled enormously huge (up to around 100 m across) forms were recognized in the early 80s of the last century. Presently, they are completely exploited.
The karst forms were fragments of extensive circulation system. It was fed by waters of elevated temperature, rich in endogenic CO2, which is proved by fluid inclusion analysis and stable isotope investigation. The origin of this system was associated with volcanic activity. The roots of the system are represented by fissures filled with coarse crystalline, red and white calcites of onyx type, which are common in the Dębnik Anticline. Water issuing from this system on the surface caused precipitation of red travertines. These travertines are preserved only as clasts in the Lower Permian conglomerates deposited in the local tectonic depressions.
The study was financed by Ministry of Science and Higher Education project N307 022 31/1746.

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