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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. ...

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That geologic hazard is a naturally occurring or man-made geologic condition or phenomenon that presents a risk or is a potential danger to life and property. examples include landsliding, flooding, earthquakes, ground subsidence, coastal and beach erosion, faulting, dam leakage and failure, mining disasters, pollution and waste disposal, and seawater intrusion [1].?

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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 shield (Keyword) returned 21 results for the whole karstbase:
Showing 1 to 15 of 21
Algological studies in the cave of Matyas Mount, Budapest, Hungary., 1966, Hajdu Lajos.
Experiments were designed to test the ability of the aphotic speleoenvironment to support algal growth. The first series contained gelatin cultures of Scenedesmus placed in the cave at different localities in order to establish whether or not the microhabitats have any particular effect on the multiplication of the algae. No differences were found in the cultures after a three month incubation period in the cave, which could be traced to influences of microenvironmental conditions. Chlorella cultures in sterile Knop's solution showed measurable growth in the cave whereas if the cultures were installed into sterilized cave water or were shielded by lead against possible radiation effects, no appreciable growth occurred. The presence or absence of magnetic field did not noticeably influence algal development. The experiments seemed to indicate that the algae tested are able to utilize soma kind of radiation in the complete darkness of the cava since, in the absence of organic material, appreciable amounts of molecular hydrogen or symbiotic activity, with iron bacteria, considerable growth occurred in a simple, strictly inorganic medium, whereas the cave waters seam to be deficient in some kind of inorganic salt required for algal nutrition. An investigation of algae living in the cave led to the determination of ten different taxa, the majority of which were Cyanophytes. Besides them, however, the cave may contain a more diversified algal population.

Ecological and Faunistic Data on the Stenasellidae (Crustacea Isopoda Asellota of Subterranean Waters)., 1974, Magniez Guy
Some important morphological features, which are discussed here, point out that the Stenasellids (Crustacea Isopoda Asellota) must be considered as a true family (Stenasellidae), independent from the Asellidae. A definition and a renewed diagnosis of the Stenasellidae Dudich, 1924, are given. Their relationships must be pursued, especially in the marine Parastenetroidea and in the psammic Microcerberidae. Until 1938, the group was known only from subterranean waters of southern Europe. Now, several genera and many thermophile species from north-tropical underground waters have been discovered in Africa (5 gen., 12 sp.), Asia (1 gen., 2 sp.) and Central America (1 gen., 4 sp.). The Stenasellids are very active burrowers. Such a behaviour explains how their phyletic lines had colonized the continental underground waters, by migrations from the littoral gravels to the underflow of rivers, phreatic alluvial waters and fnally, to the karstic waters. The typical medium for the life of the group is represented by the phreatic zones of African shields arenas. In European phyletic lines, the speciation seems to be linked with tertiary subsidences (within the Tyrrhenian area, for the line of Stenasellus virei). The European species which have survived quaternary glaciations may have diversified themselves (rising of subspecies), recolonizing newly vacant biotopes in postglacial ages.

Biogeographical and Paleobiogeographical Problems in Stenasellids (Crustacea Isopoda Asellota of Underground Waters)., 1981, Magniez Guy
Considering their systematic isolation among present Asellota, their strong burrowing behaviour, their aptitude for interstitial life and their wide north-tropical present distribution, the history of Stenasellid Crustaceans seems to be marked by the antiquity of their settlements in continental groundwaters (Middle Cretaceous period?) and a long stage of life in phreatic waters on permanently emerged paleotropical continents during the Cenozoic Era. The resemblance between some forms of the Guinean shield and Mexico sets the problem of the anteriority of their continental conquest to South Atlantic drift. The repartition of Mediterranean European forms appears as a consequence of paleogeographical changes in Tertiary Times. The distribution of continental European forms has been marked by Quaternary climatic alterations: severe curtailment of settlements, endemicity in Glacial periods but wide Holocene expansion for the forms adapted to new climatic conditions.

Principal features of evaporite karst in Canada, 1997, Ford Dc,
Outcrops of sulfate arid mixed sulfate-carbonate rocks are common everywhere in Canada outside of the Shield province. Interstratal salt deposits are abundant in the interior lowlands. Types of karst that occur are determined chiefly by relations between (i) formation thickness and purity, (ii) regional topography and hydraulic gradient (iii) effects of receding Wisconsinan and earlier glaciers, and (iv) extent of modern permafrost. Exposures of bare karst on thick, pure sulfate formations are comparatively rare. Two principal landform types found on them are: (1) high-density polygonal karst (micro-sinkhole densities of thousands per km(2)); where hydraulic gradients are high and tills are thin; (2) hills and ridges of blocks uplifted and fractured by hydration (anhydrite) tectonics at paleo-icefront positions where hydraulic gradients are low. Deeply till-mantled karst dominated by collapse and suffosion sinkholes in the mantling detritus is well developed in southwestern Newfoundland and in central and northern Nova Scotia. Covered karst is abundant on sulfates conformably overlain by carbonate br elastic strata; collapse sinkholes ale the principal landform. Very large breccia pipes (up to 25 x 15 km) ale associated with deep subrosion of salt during glacier recessions. Syngenetic breccia karst is a fourth, distinct category created in some formations of thin, interbedded dolostones and sulfates. Where these are exposed td high hydraulic gradients, deep calcite-cemented breccias were formed in a first generation, upon which sinkhole and pinnacle karsts and dissolution drape topographies were able to develop rapidly in late-glacial and post-glacial conditions

Pre-Devonian landscape of the Baltic Oil-Shale Basin, NW of the Russian Platform, 1999, Puura Vaino, Vaher Rein, Tuuling Igor,
The erosional relief of Ordovician and Silurian deposits in Estonia was developed during the continental period in late Silurian and early-middle Devonian times. The uplift of the area and marine regression were induced by compressional tectonics in the continental interior related to the closure of the Iapetus and Tornqvist Oceans. In the northern part of the Baltic sedimentary basin (Estonia), on the gentle southerly dipping slope between the Fennoscandian Shield (Finland) and Baltic Syneclise (Latvia), a pre-Devonian, slightly rugged erosional relief with few cuesta was developed. The pre-Devonian erosional landforms -- hills, depressions and escarpments reaching 150 m in height -- were probably buried under the Devonian deposits and then partly re-exposed by pre-Quaternary erosion. These landforms are described in detail using data from several thousands of cores drilled in the course of oil-shale and phosphorite exploration and mining

Karst-like landforms and hydrology in quartzites of the Venezuelan Guyana shield: Pseudokarst or 'real' karst?, 1999, Doerr Sh,
The surfaces of table mountains (Tepuis) in southeastern Venezuela display well-developed karst topography including caves, sinkholes and karren-features. Although the rock (orthoquartzite of the Precambrian Roraima Formation) has a very low solubility, active cave systems are present with passages more than one kilometre in length, descending to more than 300 metres depth. These dimensions are greater than any so far reported in quartzitic rocks. There is strong evidence that corrosive rather than erosive processes are responsible for the karstification. Thin-sections of rock samples show dissolution not only of the amorphous silica cement, but also of the crystalline quartz grains themselves. Together with field observations in and near an active cave system on the Kukenan Tepui, this indicates a close similarity between the processes active on the Venezuelan table mountains and karstification processes in rocks of greater solubility. A combination of factors including high precipitation (4000-7000 mm/year), rock of very high purity (98 % silica) and the absence of other significant geomorphological processes prevailing for at least several million years are thought to have enabled a spectacular karst landscape to evolve in a rock that in the past has been regarded as almost immune to chemical weathering

Speleothem fall (an example of a sudden stalactite collapse in Škocjanske Jame), 1999, Kranjc, Andrej

On March 2 or 3, 1999 a stalactite fell from the roof in Velika Dvorana (Tiha Jama, Škocjanske Jame). This was a cave shield or palette developed on the ceiling, 17 m above the floor. Stalactites up to 2 m long were hanging on the underside of the shield. The collapsed stalactite mass weighed about 2500 kg. On the floor it split into some large (up to 300 kg) and many smaller pieces. The author thinks that bulk fell off as it reached its critical weight. The speleothem type called "shield" is extremely fragile and not well fixed at its base. In the place where this shield developed there is a strong (up to one l/min) inflow of saturated water and it has been estimated up to 2,5 kg of flowstone/year could be deposited. In Škocjanske Jame active shield-like stalactites mostly have fallen from the roof in the places where they are fed by saturated water. However, in a human timescale such events are extremely rare.


La grotte et le karst de Cango (Afrique du Sud), 2000, Martini, J. E. J.
The author describes a small karst area in the extreme south of the African Continent, with special reference to the Cango Cave, which is a major tourist attraction. Compared with the other karsts of Southern Africa, this area is unique. The karst is typically exogenic, with caves forming by stream disappearance into swallow holes, where the thalweg intersects steeply dipping Precambrian limestone. Wet caves are vadose, with only short phreatic segments and exhibit rectilinear, longitudinal sections. Passages are low, but wide with bevelled ceilings, often terraced. This peculiar morphology is typical of the caves developing exactly on the water-table and seems to be controlled by the abundance of sediments introduced from the swallow holes. If one excepts a short active lower level, Cango is a dry cave of the same type than the wet ones. It is practically linear in plan and in profile, with a length of 2.6 km from entrance to end for a total of 5.2 km of passages. The age of the speleogenesis has been estimated as early Pleistocene from the entrance elevation, which is in between the altitude of the actual thalweg and the one of the Post African I erosion surface, which started to be eroded during the Upper Pliocene. This relatively young age is in contrast with a Miocene model, which was accepted by most of the previous authors. Cango is well adorned with speleothems, in particular with outstanding abundant shields, monocrystalline stalagmites and pools coated with calcite crystals. In the first chambers from entrance, the speleothems have been deeply corroded by bat guano, with deposition of hydroxylapatite. Previously this corrosion was attributed to resolution due to several rises of the paleowater-table. The meteorology is discussed, in particular the high carbon dioxide, which indicates that the cave is poorly ventilated and which constitutes a problem for management and conservation.

Review: What is karst?, 2000, Goede, Albert

A review of a paper by Doerr, S.H., 1999, Karst-like landforms and hydrology in quartzites of the Venezuelan Guyana shield: pseudokarst or "real" karst? Zeitschrift fur Geomorphology, 43(1), 1-17. The erosion process appears to involve solution of the silica, not just weathering of the cement.


Central Aldan gold deposits, 2002, Vetluzhskikh V. G. , Kazansky V. I. , Kochetkov A. Y. , Yanovsky V. M. ,
The Central Aldan ore district stands out in many features against the other gold districts within the Aldan Shield. The gold, uranium, and other mineral deposits are located at a junction of regional structures, they originated within a relatively short time interval of about 100 Ma, the ore mineralization is closely spatially and genetically related to alkaline magmatism, the igneous rocks and related ore deposits are located within a concentric-radial structure, and the host rocks consist of basement and sedimentary cover contrasting in physicochemical properties. All these features allow us to consider the Central Aldan district as an endogenous ore-magmatic system. The Aldan complex of primarily ore-bearing alkaline basaltic crustal-mantle volcanic and plutonic rocks originated during four to five stages and numerous intrusive phases and extensive magma differentiation in mature continental crust including thin horizontally heterogeneous platform cover. Some facts considered in this paper allowed us, however, to comprise the whole series of Central Aldan gold deposits as an endogenous-exogenous ore-forming system characteristic of the tectonically activated regions of ancient platforms. The evolution of the Central Aldan district in the Jurassic, Cretaceous, and Cenozoic developed during the tectonic activation of Precembrian structures, oxidation of primary ores and weathering crust formation, and exposure of the Lebedinsk-, Kuranakh-, Ryabinovsk-, and Samolazovsk-type gold deposits to the erosion level. The formation of underground and surficial karst systems was initiated during the Jurassic weathering of carbonate rocks of the platform cover in subaerial environments. The endogenous stage of ore concentration was here directly followed by an exogenous stage with the formation of weathered rocks and gold placers in various morphostructural local environments, e.g., horsts, grabens, and graben valleys. Specific features of the placer structures and gold, quality in various placer types are related with hypogene ore bodies and elements of ore-controlling structures and zones of primary disseminated mineralization. The ore bodies of the Kuranakh and Samolazovskoe deposits actually belong to new types of endogenous-exogenous deposits. The gold dispersion and concentration related to karst formation are also significant in this ore district. Thus, Central Aldan is also an ore-placer district with specific features

The unique Central Aldan gold-uranium ore district (Russia), 2004, Kazansky V. I. ,
In recent years, problems of the formation and distribution of ore deposits large and unique in their origin and scale have been discussed in publications and at international geological meetings. The aim of the present article is to show that not only individual deposits, but also ore districts may be unique. Such ore districts, for example, the Central Aldan gold-uranium ore district, contain deposits of various origins that belong to the same metallogenic epoch and were formed in similar geodynamic conditions. The Central Aldan gold-uranium ore district, with its resources of Au of 1000 t and U of 600000 t, is interpreted as a single unit. Its unique features are reflected at different levels: transregional, regional, and local. At the transregional level, its position is defined by the superposition of intense Mesozoic epicontinental tectonics, calc-alkaline-alkaline magmatism, and extensive hydrothermal ore mineralization on consolidated Early Precambrian structures of the Aldan Shield. In the Mesozoides of East Asia, Au and U deposits are located separately from each other except for in the Central Aldan district, where these deposits occur jointly and possess unique features. The interrelation between the Early Precambrian and the ore-bearing Mesozoic structures is clearly manifested in the Aldan Shield itself. The Central Aldan ore district is situated at the conjunction of the two largest megablocks, the Aldan-Timpton and Timpton-Uchur, which 2 Ga ago were transformed into a gneiss-granulite terrane. The Central Aldan district is confined to the periphery of a giant dome made up of Early Precambrian rocks of the Iengra complex. This district contains the largest and most varied subvolcanic caic-alkaline-alkaline intrusions. Finally, on the local scale, the Central Aldan magmatectonogen appears as the main ore-controlling factor. It consists of radial and ring faults cutting the crystalline basement and platform cover. It defines the distribution of Mesozoic magmatic rocks and various deposits in different radial blocks. The Central Aldan district contains three main types of ore deposits that form the following independent ore fields: the hydrothermal Au-U El'kon, the hydrothermal U Lebedinsk, and the polygenetic Au Kuranakh. The first and third deposits are unique not only in their scale, but in their origin as well. Deposits of the El'kon type are confined to rejuvenated faults of the crystalline basement and are characterized by exclusive extension of low-temperature Au-U mineralization. The third, Kuranakh type, in many respects enigmatic, is characterized by the presence of gold-bearing karst clays at the contact of platform limestones with Jurassic sandstones. The data presented in this article were accumulated during the 70-year history of the study and development of the Central Aldan district. Some deposits have been worked out and others preserved from operation due to different reasons. Many problems of the origin of ore deposits in the Central Aldan district have not yet been solved, and its total ore potential is far from being established

Geological, structural and geochemical aspects of the main aquifer systems in Kuwait, 2004, Alsulaimi Js, Alruwaih Fm,
The paper summarizes the lithology, structure and the geometry of the main aquifer systems in Kuwait (the Dammam Formation and the Kuwait Group) along with the hydrochemical characteristics of the aquifers. Kuwait lies between the Arabian Shield and Zagros fold belt at the periphery of the Arabian platform. Structures associated with the Kuwait Arch noticeably control the subsurface configuration of the Dammam Formations and, hence regulate the distribution of the overlying Kuwait Group sediments. For the broad setting, the paleogeography of the Eocene has been constructed. The main lithologies of concern, both in the surface and subsurface, are the recent and subrecent sediments. The Kuwait Group includes the Dibdibba Formation, and the undifferentiated Ghar and Fars Formations, as well as the Hasa Group comprising the Dammam, Rus and Umm Er-Radhuma Formations. Subsurface geological cross-sections were constructed for the Dammam Formation, showing its structures, configuration, unconformity, and zones of uplift. Potential sites of karst formation in the Dammam limestone have been identified in the cross-sections. The structural study enables the reconstruction of the paleomorphostructural sections of the Dammam Formation. The chemical investigation indicates that the Kuwait Group aquifer is occupied by Na2SO4 and NaCl water types. In addition, the Kuwait Group aquifer is supersaturated with respect to calcite and is undersaturated with respect to halite, gypsum, anhydrite and dolomite. The Dammam Formation aquifer has Na2SO4, CaSO4 and NaCl water types. Moreover, the Dammam Formation is supersaturated with calcite and dolomite and is undersaturated with respect to halite, gypsum, and anhydrite. The calculated mean values of the PCO2 of the Kuwait Group and the Dammam Formation aquifers are 3.8 x 10(-3) atm. and 2.99 x 10(-3) atm. respectively, which are significantly above the PCO2 of the Earth's atmosphere. This may suggest a deep closed environment

Underground drainage systems and geothermal flux, 2005, Badino, G.

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.


Dating of caves by cosmogenic nuclides: method, possibilities, and the Siebenhengste example, 2005, Hä, Uselmann Philipp, Granger Darryl E.

Cosmic rays produce nuclides at and near the Earth's surface. 10Be and 26Al in quartz are of particular interest for dating cave sediments. These two nuclides are produced at the surface at a fixed ratio. If the quartz is carried from the surface into a cave, the sediment is shielded from additional cosmogenic nuclide production, and the inherited 10Be and 26Al decay radioactively. Because 26Al decays more rapidly than 10Be, the ratio of these two nuclides indicates the time since the sediment was washed underground. The burial dating method can be applied to sediments in the age range of approximately 0.1 to 5 Ma. In ideal cases, we get information about valley lowering rates. If the provenance of the sediment is known, averaged erosion rates of the source area can be estimated. The oldest cave phases of the Siebenhengste system, Switzerland, were dated using cosmogenic nuclides. The oldest sediment is 4.4 ± 0.6 Ma and thus indicates Pliocene karstification of the Siebenhengste.


Underground drainage systems and geothermal flux, 2005, Badino, Giovanni

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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