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Enviroscan Ukrainian Institute of Speleology and Karstology


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Community news

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 ridge is an elongated narrow elevation [16].?

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


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KarstBase a bibliography database in karst and cave science.

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 brines (Keyword) returned 34 results for the whole karstbase:
Showing 31 to 34 of 34
MORPHOLOGY AND GENESIS OF THE MAIN ORE BODY AT NANISIVIKZINC/LEAD MINE, BAFFIN ISLAND, CANADA: AN OUTSTANDING EXAMPLEOF PARAGENETIC DISSOLUTION OF CARBONATE BEDROCKS WITHPENE-CONTEMPORANEOUS PRECIPITATION OF SULFIDES AND GANGUEMINERALS, 2009,
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Ford D.

Nanisivik (Inuit – “the place where they find things’) zinc/lead mine is located at Lat. 73o N in northwestern Baf?n Island. The host rock is a Proterozoic platform carbonate 260-800 m thick, medium to massively bedded and pervasively dolomitized. It rests on mixed shales and shaly dolomites, and is overlain by 150+ m of further shales functioning as an aquitard. These formations were buried by later Proterozoic strata, uplifted, eroded and buried again in a Cambrian sedimentary basin. The ore-grade deposits are contained within a horst block of the dolomites dipping NW at 15o across it. Graben to the north and south are roofed in the overlying shales. The principal deposit, the Main Ore, is of zinc, lead and iron sul?de precipitates plus gangue minerals, chie?y secondary dolomite. It extends for three km E-W along the horst. It is horizontal, at ~300 m above sea level and terminated at both ends by modern valley entrenchments. The Main Ore body is consistently ~100 m in width and ?ve-seven m in depth. This wide ceiling is a nearly planar, horizontal corrosion bevel. The sulfdes scarcely extend above it anywhere. Within the Main Ore two or more generations of tapered ?ns of dolomite in situ extend from both south (updip) and north (downdip) walls into the cavity. Fin surfaces truncate the bedding. Edges of ?ns are sinuous, some meandering with a wavelength of ~50 m. Very sharp, horizontal corrosion notches 20-30 cm high extend into the dolomite walls for at least 20 m (the limit of deep crosscuts in the mine). They are ?lled with layered pyrites which continue out into the ore body as regular sheets truncating earlier, dipping mineral layers until they themselves are truncated by later fillings. One exceptional notch, one meter deep, is at least 350 m in breadth. The ore displays four sedimentary modes: (i) regular layers settled or precipitated onto the cavity floor; (ii) chaotic polymict breccias suggestive of channel cut-and-?ll episodes; (iii) the horizontal pyrite sheets in corrosion notches; (iv) minor metasomatic replacements of dolomite. The ore cavity was created by paragenesis in a channel ?ow mode, with ore and gangue deposition on the floor taking place in tandem with dissolutional cavity creation upwards,. Principal deposition took place when a fluid interface could be rigorously maintained. Fluid inclusions indicate derivation of the metals from exchange reactions with metalliferous sediments (the underlying shales), indicating low water/rock ratios and moderate temperatures. The ore fluids were similar to oil field brines. Sulfur isotope fractionations indicate temperatures of 90-150 +/-40o C, suggesting that the Main Ore formed along a gas/brine interface at a depth of at least 1600 m as a consequence of ?uid expulsion in the subsiding Cambrian sedimentary basin.


Geochemical/isotopic evolution of Pb-Zn deposits in the Central and Eastern Taurides, Turkey, 2011,
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Hanilci N. , Ozturk H.

The Central and Eastern Taurides contain numerous carbonate-hosted Pb-Zn deposits, mainly in Devonian and Permian dolomitized reefal-stramatolitic limestones, and in massive Jurassic limestones. We present and compare new fluid inclusion and isotopic data from these ore deposits, and propose for the first time a Mississippi Valley-type (MVT) mode of origin for them. Fluid inclusion studies reveal that the ore fluids were highly saline (13-26% NaCl equiv.), chloride-rich (CaCl2) brines, and have average homogenization temperatures of 112°C, 174.5°C, and 211°C for the Celal Dag, Delikkaya, and Ayrakl deposits, respectively. Furthermore, the ?34S values of carbonate-hosted Pb-Zn deposits in the Central and Eastern Taurides vary between -5.4‰ and +13.70‰. This indicates a possible source of sulphur from both organic compounds and crustal materials. In contrast, stable sulphur isotope data (average ?34S -0.15‰) for the Cadrkaya deposit, which is related to a late Eocene-Oligocene (?) granodioritic intrusion, indicates a magmatic source. The lead isotope ratios of galena for all investigated deposits are heterogeneous. In particular, with the exception of the Sucat district, all deposits in the Eastern (Delikkaya, Ayrakl, Denizovas, Cadrkaya) and Central (Katranbasi, Kucuksu) Taurides have high radiogenic lead isotope values (206Pb/204Pb between 19.058 and 18.622; 207Pb/204Pb between 16.058 and 15.568; and 208Pb/204Pb between 39.869 and 38.748), typical of the upper continental crust and orogenic belts. Fluid inclusion, stable sulphur, and radiogenic lead isotope studies indicate that carbonate-hosted metal deposits in the Eastern (except for the Cadrkaya deposit) and the Central Taurides are similar to MVT Pb-Zn deposits described elsewhere. The primary MVT deposits are associated with the Late Cretaceous-Palaeocene closure of the Tethyan Ocean, and formed during the transition from an extensional to a compressional regime. Palaeogene nappes that typically limit the exposure of ore bodies indicate a pre-Palaeocene age of ore formation. Host rock lithology, ore mineralogy, fluid inclusion, and sulphur + lead isotope data indicate that the metals were most probably leached from a crustal source such as clastic rocks or a crystalline massif, and transported by chloride-rich hydrothermal solutions to the site of deposition. Localization of the ore deposits on autochthonous basement highs indicates long-term basinal fluid migration, characteristic of MVT depositional processes. The primary MVT ores were oxidized in the Miocene, resulting in deposition of Zn-carbonate and Pb-sulphate-carbonate during karstification. The ores underwent multiple cycles of oxidation and, in places, were re-deposited to form clastic deposits. Modified deposits resemble the 'wall-rock replacement' and the 'residual and karst fill' of non-sulphide zinc deposits and are predominantly composed of smithsonite


Isotopes of Carbon in a Karst Aquifer of the Cumberland Plateau of Kentucky, USA, 2013,
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Florea Lee J.

In this study, the concentration and isotopic composition of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) are measured in the karst groundwater of the Otter Creek watershed of the Cumberland Plateau of Kentucky, USA. Comparisons among these data and with the geochemistry of carbonate and gypsum equilibrium reactions reveal that DOC concentration is inversely related to discharge, multiple reaction pathways provide DIC with isotopic enrichment that may be directly related to mineral saturation, and oxidation of reduced sulfur is possible for dissolution. DOC is derived from C3 vegetation with an average δ13C DOC of ‒27‰. DIC in groundwater is derived from both pedogenic CO2  and HCO3 - from dissolved carbonate. At input sites to the karst aquifers DIC concentrations are expectedly low, less than 1 mmol/L, in waters that are undersaturated with respect to calcite. At the output of these karst aquifers DIC concentrations reach 3 mmol/L in waters that are at or above calcite saturation. Values of δ13C DIC range between ‒6.3 and ‒12.4‰ with CO2 degassing and calcite precipitation at some sites obfuscating a simple relationship between δ13C DIC, discharge, and mineral saturation. In addition, concentrations of DIC in sulfur seeps within the watershed range between 2–7 mmol/L with δ13C DIC values in some samples skewed more toward the anticipated value of carbonate bedrock than would be expected from reactions with carbonic acid alone. This suggests that the oxidation of reduced sulfur from shallow oilfield brines liberates bedrock DIC through reactions with sulfuric acid.


Karstification of Dolomitic Hills at south of Coimbra (western-central Portugal) - Depositional facies and stratigraphic controls of the (palaeo)karst affecting the Coimbra Group (Lower Jurassic), 2014,
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Dimuccio, Luca Antonio

An evolutionary model is proposed to explain the spatio-temporal distribution of karstification affecting the Lower Jurassic shallow-marine carbonate succession (Coimbra Group) of the Lusitanian Basin, cropping out in the Coimbra-Penela region (western-central Portugal), in a specific morphostructural setting (Dolomitic Hills). Indeed, in the Coimbra Group, despite the local lateral and vertical distributions of dolomitic character and the presence of few thick sandy-argillaceous/shale and marly interbeds, some (meso)karstification was identified, including several microkarstification features. All types of karst forms are commonly filled by autochthonous and/or allochthonous post-Jurassic siliciclastics, implying a palaeokarstic nature.

The main aim of this work is to infer the interplay between depositional facies, diagenesis, syn- and postdepositional discontinuities and the spatio-temporal distribution of palaeokarst. Here, the palaeokarst concept is not limited to the definition of a landform and/or possibly to an associated deposit (both resulting from one or more processes/mechanisms), but is considered as part of the local and regional geological record.

Detailed field information from 21 stratigraphic sections (among several dozens of other observations) and from structural-geology and geomorphological surveys, was mapped and recorded on graphic logs showing the lithological succession, including sedimentological, palaeontological and structural data. Facies determination was based on field observations of textures and sedimentary structures and laboratory petrographic analysis of thin-sections. The karst and palaeokarst forms (both superficial and underground) were classified and judged on the basis of present-day geographic location, morphology, associated discontinuities, stratigraphic position and degree of burial by post-Jurassic siliciclastics that allowed to distinguish a exposed karst (denuded or completely exhumed) than a palaeokarst (covered or partially buried).

A formal lithostratigrafic framework was proposed for the local ca. 110-m-thick combined successions of Coimbra Group, ranging in age from the early Sinemurian to the early Pliensbachian and recorded in two distinct subunits: the Coimbra formation, essentially dolomitic; and the overlying S. Miguel formation, essentially dolomitic-limestone and marly-limestone.

The 15 identified facies were subsequently grouped into 4 genetically related facies associations indicative of sedimentation within supra/intertidal, shallow partially restricted subtidal-lagoonal, shoal and more open-marine (sub)environments - in the context of depositional systems of a tidal flat and a very shallow, inner part of a low-gradient, carbonate ramp. In some cases, thick bedded breccia bodies (tempestites/sismites) are associated to synsedimentary deformation structures (slumps, sliding to the W to NW), showing the important activity of N–S and NNE–SSW faults, during the Sinemurian. All these deposits are arranged into metre-scale, mostly shallowing-upward cycles, in some cases truncated by subaerial exposure events. However, no evidence of mature pedogenetic alteration, or the development of distinct soil horizons, was observed. These facts reflect very short-term subaerial exposure intervals (intermittent/ephemeral), in a semiarid palaeoclimatic setting but with an increase in the humidity conditions during the eogenetic stage of the Coimbra Group, which may have promoted the development of micropalaeokarstic dissolution (eogenetic karst).

Two types of dolomitization are recognized: one (a) syndepositional (or early diagenetic), massive-stratiform, of “penesaline type”, possibly resulting from refluxing brines (shallow-subtidal), with a primary dolomite related to the evaporation of seawater, under semiarid conditions (supra/intertidal) and the concurrent action of microbial activity; another (b) later, localized, common during diagenesis (sometimes with dedolomitization), particularly where fluids followed discontinuities such as joints, faults, bedding planes and, in some cases, pre-existing palaeokarstic features.

The very specific stratigraphic position of the (palaeo)karst features is understood as a consequence of high facies/microfacies heterogeneities and contrasts in porosity (both depositional and its early diagenetic modifications), providing efficient hydraulic circulation through the development of meso- and macropermeability contributed by syn- and postdepositional discontinuities such as bedding planes, joints and faults. These hydraulic connections significantly influenced and controlled the earliest karst-forming processes (inception), as well as the degree of subsequent karstification during the mesogenetic/telogenetic stages of the Coimbra Group. Multiple and complex karstification (polyphase and polygenic) were recognized, including 8 main phases, to local scale, integrated in 4 periods, to regional scale: Jurassic, Lower Cretaceous, pre-Pliocene and Pliocene-Quaternary. Each phase of karstification comprise a specific type of (palaeo)karst (eogenetic, subjacent, denuded, mantled-buried and exhumed).

Finally, geological, geomorphological and hydrogeological characteristics allowed to describe the local aquifer. The elaborated map of intrinsic vulnerability shows a karst/fissured and partially buried aquifer (palaeokarst) with high to very high susceptibility to the contamination.


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