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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 rout, to is the action of predicting and directing of flood waves through a channel system [16].?

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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.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Featured articles from other Geoscience Journals
Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Search in KarstBase

Your search for hypogen (Keyword) returned 376 results for the whole karstbase:
Showing 1 to 15 of 376
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.

Dissolution of salt deposits by brine density flow, 1980, Anderson R. Y. , Kirkland D. W

Limestone caves form along ground-water paths of greatest discharge and solutional aggressiveness. Flow routes that acquire increasing discharge accelerate in growth, while others languish with negligible growth. As discharge increases, a maximum rate of wall retreat is approached, typically about 0.01-0.1 cm/yr, determined by chemical kinetics but nearly unaffected by further increase in discharge. The time required to reach the maximum rate is nearly independent of kinetics and varies directly with flow distance and temperature and inversely with initial fracture width, discharge, gradient, and P(CO2). Most caves require 10(4) - 10(5) yr to reach traversable size. Their patterns depend on the mode of ground-water recharge. Sinkhole recharge forms branching caves with tributaries that join downstream as higher-order passages. Maze caves form where (1) steep gradients and great undersaturation allow many alternate paths to enlarge at similar rates or (2) discharge or renewal of undersaturation is uniform along many alternate routes. Flood water can form angular networks in fractured rock, anastomotic mazes along low-angle partings, or spongework where intergranular pores are dominant. Diffuse recharge also forms networks and spongework, often aided by mixing of chemically different waters. Ramiform caves, with sequential outward branches, are formed mainly by rising thermal or H2S-rich water. Dissolution rates in cooling water increase with discharge, CO2 content, temperature, and thermal gradient, but only at thermal gradients of more than 0.01-degrees-C/m can normal ground-water CO2 form caves without the aid of hypogenic acids or mixing. Artesian flow has no inherent tendency to form maze caves. Geologic structure and stratigraphy influence cave orientation and extent, but alone they do not determine branch-work versus maze character

Classification of cave dypsum deposits derived from oxidation of H2S, 1994, Buck M. J. , Ford D. C. , Schwarcz H. P.

Lechuguilla Cave is a deep, extensive, gypsum- and sulfur-bearing hypogenic cave in Carlsbad Caverns National Park, New Mexico, most of which (> 90%) lies more than 300 m beneath the entrance. Located in the arid Guadalupe Mountains, Lechuguilla's remarkable state of preservation is partially due to the locally continuous Yates Formation siltstone that has effectively diverted most vadose water away from the cave. Allocthonous organic input to the cave is therefore very limited, but bacterial and fungal colonization is relatively extensive: (1) Aspergillus sp. fungi and unidentified bacteria are associated with iron-, manganese-, and sulfur-rich encrustations on calcitic folia near the suspected water table 466 m below the entrance; (2) 92 species of fungi in 19 genera have been identified throughout the cave in oligotrophic (nutrient-poor) ''soils'' and pools; (3) cave-air condensate contains unidentified microbes; (4) indigenous chemoheterotrophic Seliberius and Caulobacter bacteria are known from remote pool sites; and (5) at least four genera of heterotrophic bacteria with population densities near 5 x 10(5) colony-forming units (CFU) per gram are present in ceiling-bound deposits of supposedly abiogenic condensation-corrosion residues. Various lines of evidence suggest that autotrophic bacteria are present in the ceiling-bound residues and could act as primary producers in a unique subterranean microbial food chain. The suspected autotrophic bacteria are probably chemolithoautotrophic (CLA), utilizing trace iron, manganese, or sulfur in the limestone and dolomitic bedrock to mechanically (and possibly biochemically) erode the substrate to produce residual floor deposits. Because other major sources of organic matter have not been detected, we suggest that these CLA bacteria are providing requisite organic matter to the known heterotrophic bacteria and fungi in the residues. The cavewide bacterial and fungal distribution, the large volumes of corrosion residues, and the presence of ancient bacterial filaments in unusual calcite speleothems (biothems) attest to the apparent longevity of microbial occupation in this cave

Occurrence of hypogenic caves in a karst region: examples from central Italy., 1995, Galdenzi S. , Menichetti M.

The caves of the Umbria and Marche regions in central Italy are made up of three-dimensional maze systems that display different general morphologies due to the various geological and structural contexts. At the same time, the internal morphologies of the passages, galleries, and shafts present some similarity, with solutional galleries characterized by cupolas and blind pits, anastamotic passages, roof pendants, and phreatic passages situated at different levels. Some of these caves are still active, as is the case for Frassassi Gorge, Parrano Gorge, and Acquasanta Terme, with galleries that reach the phreatic zone, where there is a rising of highly mineralized water, rich in hydrosulfydric acid, and with erosion of limestone walls and the formation of gypsum. Elsewhere there are fossil caves, such as Monte Cucco and Pozzi della Piana, where large speleothems of gypsum are present 500 m or more above the regional water table. In all of these important karst systems it is possible to recognize basal input points through fracture and intergranular porosity networks at the base of the oxidizing zone in the core of the anticline, where mineralized water rises up from the Triassic evaporitic layers in small hydrogeological circuits. Different underground morphologies can derive from the presence of a water table related to an external stream or from the confined setting of the carbonate rocks, underlying low permeable sedimentary cover, where artesian conditions can occur

Symposium Abstract: Hypogenetic karst and climatic change in North-Eastern Brazil, 1996, Auler A. S.

Occurrence and significance of stalactites within the epithermal deposits at Creede, Colorado, 1996, Campbell Wr, Barton Pb,
In addition to the common and abundant features in karst terranes, stalactites involving a wide variety of minerals have also been found in other settings, including epigenetic mineral deposits, bur these are almost always associated with supergene stages. Here we describe a different mode of occurrence from the Creede epithermal ore deposits, in Colorado, wherein stalactites of silica, sphalerite, galena, or pyrite formed in a vapor-dominated setting, below the paleo-water table, and except possibly for pyrite, as part of the hypogene mineralization. Axial cavities may, or may not, be present. No stalagmites have been recognized. The stalactites are small, from a few millimeters to a few centimeters long and a few millimeters in outer diameter. They represent only a small fraction of one percent of the total mineralization, and are covered by later crystals. Their growth orientation usually is unobservable; however, the parallel arrangement of all stalactites in a given specimen, consistency with indicators of gravitational settling, and the common presence of axial structures make the stalactitic interpretation almost unavoidable. In contrast with common carbonate stalactites, the growth mechanism for th sulfide and silica stalactites requires extensive evaporation. Stalactitic forms have also been reported from other deposits, mostly epithermal or Mississippi Valley-type occurrences, but we caution that stalactite-like features can form by alternative processes

Initial Geologic Observations in Caves Bordering the Sibari Plain (Southern Italy), 1997, Galdenzi, S.
Geologic investigation of caves in the northern Calabria region of Italy has clarified their origin and irregular distribution. Caves and surface karst landforms are not widespread, despite the fact that the local limestones are widely exposed and surface drainage is poorly developed. The caves are located in small limestone hills and mountains around the Sibari Plain and are surrounded by low-permeability rocks. Among them is a significant shaft cave fed by a sinking stream that drains a non-karst recharge area. However, most of the caves are predominantly horizontal and have entrances at low altitudes at several levels. Their origin is due to the rising of thermal waters, which are mineralized after passing through the Neogene formations of the Sibari Plain. The caves can be considered relict hypogenic outflow caves. The main cave-forming process was probably the oxidation of H2S, favored by the mixing of thermal water and infiltrating fresh water. Oxidation of H2S has resulted in gypsum deposits within the caves.

Geology, geochemistry, and origin of the continental karst-hosted supergene manganese deposits in the western Rhodope massif, Macedonia, northern Greece, 1997, Nimfopoulos M. K. , Pattrick R. A. D. , Michailidis K. M. , Polya D. A. , Esson J. ,
Economic Mn-oxide ore deposits of commercial grade occur in the Rhodope massif near Kato Nevrokopi in the Drama region, Northern Greece. The Mn-oxide mineralization has developed by weathering of continental hypogene rhodochrosite-sulphide veins. The vein mineralization is confined by tectonic shear zones between marble and metapelites, extending laterally into the marble as tabular, pod or lenticular oreshoots (up to 50 m x 20 m x 5-10 m). Supergene oxidation of the hypogene mineralization led to the formation of in-situ residual Mn-oxide ore deposits, and secondary infills of Mn-oxide ore in embryonic and well developed karst cavities. Whole rock geochemical profiles across mineralized zones confirm the role of thrusts and faults as solution passageways and stress the importance of these structures in the development of hydrothermal and supergene mineralization at Kato Nevrokopi. Three zones an recognized in the insitu supergene veins: (A) a stable zone of oxidation, where immobile elements form (or substitute in) stable oxide mineral phases, and mobile elements are leached; (B) a transitional (active) zone in which element behavior is strongly influenced by seasonal fluctuations of the groundwater table and variations in pH-Eh conditions; and (C) a zone of permanent flooding, where variations in pH-Eh conditions are minimal. Zone (B) is considered as the source zone for the karst cavity mineralization. During weathering, meteoric waters, which were CO2-rich (P-CO2 similar to 10(-3.8) to 10(-1.4)) and oxygenated (fO(2) -10(-17) for malachite), percolated downward within the veins, causing breakdown and dissolution of sulfides and marble, and oxidation of rhodochrosite to Mn-oxides. Karat cavity formation was favored by the high permeability along thrust zones. Dissolved Mn2 was transported into karst cavities in reduced meteoric waters at the beginning of weathering (pH similar to 4-5), and as Mn(HCO3)(2) in slightly alkaline groundwaters during advanced weathering (pH similar to 6-8). Mn4? precipitation took place by fO(2) increase in ground waters, or pH increase by continuous hydrolysis and carbonate dissolution. In the well developed karst setting, some mobility of elements occurred during and after karst ore formation in the order Na>K>Mg>Sr>Mn>As>Zn>Ba>Al>Fe>Cu>Cd>Pb. (C) 1998 Canadian Institute of Mining, Metallurgy and Petrolem. Published by Elsevier Science Ltd. All rights reserved

Hydrothermal Calcite Veins and the Origin of Caves in the Lower Paleozoic of the Barrandian Basin, Czech Republic: Evidence of Extensive (Post?) Variscan Fluid Flow, 1997, Suchy V. , Zeman A. , Bosak P. , Dobes P. , Hladikova J. , Jackova I.

Age and Origin of Carlsbad Cavern and Related Caves from 40Ar/39Ar of Alunite., 1998, Polyak V. J. , Mcintosh W. C. , Given N. , Provencio P.
40Ar/39Ar dating of fine-grained alunite that formed during cave genesis provides ages of formation for the Big Room level of Carlsbad Cavern [4.0 to 3.9 million years ago (Ma)], the upper level of Lechuguilla Cave (6.0 to 5.7 Ma), and three other hypogene caves (11.3 to 6.0 Ma) in the Guadalupe Mountains of New Mexico. Alunite ages increase and are strongly correlative with cave elevations, which indicates an 1100-meter decline in the water table, apparently related to tectonic uplift and tilting, from 11.3 Ma to the present. 40Ar/39Ar dating studies of the hypogene caves have the potential to help resolve late Cenozoic climatic, speleologic, and tectonic questions.

The evolution of karst and caves in the Konûprusy region Bohemian Karst, Czech Republic), Part II: Hydrothermal paleokarst, 1998, Bosak, Pavel

The origin of hydrothermal karst cavities was connected with the Variscan hydrothermal process. The cavities were formed and filled by crystalline calcite. The process was accompanied by the intensive dolomitisation. Younger phase of hydrothermal karstification was not connected with vein-filling, but with the deep circulation of groundwater, probably associated with neovolcanic activity in the Bohemian Massif. This is supported by pollen grains and decomposed volcanic ash in speleothems which were formed after the major phases of speleogenesis. It is supposed that caves in the Konûprusy Devonian were formed in confined aquifer under phreatic and batyphreatic conditions. Thermal conditions appeared when paleogeothermic gradient was increased due to intensive neovolcanic activity. Hydrothermal karstification partly changed the morphology of caves. The maximum temperatures were stated to 60-700 C from large calcite crystals precipitated under phreatic and deeply phreatic conditions. The piezometric level was situated above limestones in Upper Cretaceous platform siliciclastics as indicated by numerous subvertical phreatic tubes („depressions") filled with sunkened Cretaceous and Tertiary sediments after the water buyoancy support decreased. Popcorn-like silicified Konûprusy Rosettes can be result of decrease of thermal water level and mixing with infiltrating meteoric waters. Outer zones of large calcite crystals with precipitation temperatures of about 400 C can indicate the gradual cooling of the whole system.

The Vazante zinc mine, Minas Gerais, Brazil; constraints in willemitic mineralization and fluid evolution, 1999, Lena Virginia Soares Monteiro, Jorge Silva Bettencourt, Baruch Spiro, Rodnei Graca, And Tolentino Flavio De Oliveira
The Vazante Mine is located in the Vazante District, the largest zinc district in Brazil. The Vazante deposit consists dominantly of an unusual willemitic ore. Small sulfide bodies are tectonically imbricated with the willemitic ore, within the Vazante shear zone. Structural styles of deformation and petrographic and isotopic evidence indicate that willemitic mineralization and deformation occurred synchronously during the Neo-Proterozoic. Various generations of hydrothermal veins and hydraulic breccias may pre-date, accompany and overprint the mineralization. Ore-formation temperatures are deduced from stable isotope geothermometry and mineral chemistry of both sulfide bodies and willemitic ore. Temperatures during the main stage of mineralization range from 206 degrees C to 294 degrees C (willemitic ore) and 317 degrees C (sulfides), and reflect the prevailing metamorphic conditions within the shear zone. The fluid from which the gangue minerals of the sulfide bodies precipitated (at 250 degrees C) had an oxygen isotopic average value of delta 18 O = +19.4 per mil. This value appears to reflect the interaction of metamorphic fluid with the carbonate rocks of the Vazante formation. At 250 degrees C, the fluid in equilibrium with the vein mineral phases and willemitic ore assemblage exhibits a uniform oxygen isotopic composition, with an average value of delta 18 O = +11.5 per mil. The positive linear covariance of delta 18 O and delta 13 C ratios of the carbonates is most likely due to the mixing of metamorphic and meteoric fluids. The delta 34 S values of sulfides indicate a direct crustal origin for the sulfur. It is suggested that the sulfur is largely derived from pre-existing sulfide bodies and has been transported by metamorphic fluids. The willemitic ore may have originated from the precipitation of metal in sulfur-poor fluids under oxidized conditions, within the Vazante shear zone.

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