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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 maze cave pattern is a cave system which consists of a labyrinth of intersecting passages of rather uniform character that form closed loops. see also anastomotic cave pattern; maze cave; network cave pattern; spongework cave pattern.?

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;
See all featured articles from other geoscience journals

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Your search for closed depressions (Keyword) returned 28 results for the whole karstbase:
Showing 1 to 15 of 28
Diffuse flow and conduit flow in limestone terrain in the Mendip Hills, Somerset (Great Britain), 1977, Atkinson T. C.
The hydrogeology of the karstic Carboniferous Limestone is described. Water tracing has established recharge areas for fifteen major springs and water budgets confirm the size of the areas found. Groundwater flow occurs in two modes: turbulent conduit flow and diffuse Darcian flow in fine fractures. Recharge is 50% quickflow via caves and closed depressions and 50% slower percolation. Active storage in the diffuse component (S = 0.92%) is 30 times greater than in phreatic conduits. Diffuse hydraulic conductivity is 0.89 m day−1 and an average of 60?80% of groundwater is transmitted by conduits in this maturely karsted and steeply dipping aquifer.

Karst development in Ordovician carbonates: Western Platform of Newfoundland, Master of Science (MS) Thesis, 1978, Karolyi, Marika Sarolta

The Appalachian fold belt system in Newfoundland is divided into three tectonic divisions: Western Platform; Central Mobile Belt; Avalon Platform Rocks of the Western Platform range in age from Precambrian to Carboniferous. Major karst areas are found there is Ordovician and Carboniferous rocks. Karst features of the study area (Goose Arm to Bonne Bay Big Pond) are in the Ordovician carbonates of the undivided St. George and Table Head Formations, covering a few hundred square kilometers. Features include karren, sinkholes, sinking streams, and karst springs, caves and other solutional and collapse features.
In the study area multiple fold and faulting episodes complicate the geology. Extensive and probably repeated glaciations have produced rugged terrane with U-shaped valleys and as much as 300m relief on the carbonates. There is variable but thick till cover. A class or classes of ice-scoured closed depressions with internal drainage are recognized. Postglacial karst forms are limited to varieties of karren (mainly littoral), small sinkholes, and cave systems that are inaccessively small in most instances. Distribution of all karst features is highly irregular.
Hydrologic patterns follow fluvial, fluviokarstic and holokarstic drainage. Large number of sinking ponds have seasonal overflow channels. The ground water drainage routes are generally short and shallow, with varied hydraulic gradients. Few instances of ground water route integration to regional springs is found.
The water chemistry of the area displays a tight normal distribution of hardness. This is attributed to the ponding effect. Seasonal trends show an overall increase in total hardness and other parameters, with some ponds showing linear increases and others cyclic variations.
Karst type and distribution is complex and irregular, but both glaciokarstic and karstiglacial development is present. The majority of karst forms point to karstiglacial development where previous karst forms have been modified by ice. Karstification is controlled by geology, rock lithology, hydraulic gradients and glacial scour and infill. Karstic processes continue to operate today, modifying the scoured basins and creating new karst forms.

Surface Lowering and Landform Evolution on Aldabra, 1979, Trudgill S. T. ,
Aldabra landforms are the result of the karstification of carbonate rocks distributed on surfaces which have been exposed to erosion for varying lengths of time. Morphometric analysis (which is of interest in both geomorphological and botanical contexts) suggests that the most well developed karst features (closed depressions) occur on what appear to be the oldest surfaces. Morphology also varies with lithology. Measurements of present-day erosion rates suggests that weakly cemented rocks and the most soluble mineral components are eroding most rapidly. The evolution of a dissected morphology is related to lithological heterogeneity in coralline rocks or, in the case of the more homogeneous rocks, to the short residence time of waters on the rock surface (the more rapidly dissolving mineral grains eroding faster). Dissolution also proceeds in fresh water pools, but this may be offset by precipitation in some cases. The surface is mostly case hardened, except under deep organic soils where erosion rates are much higher than in other areas. A mean erosion rate measured at 0.26 mm/a appears to make it feasible that large erosional features, such as the lagoon, could have been formed during periods of emersion as suggested by research workers who have hypothesized that an atoll shape may be substantially derived by subaerial weathering

Civil engineering difficulties in the karst of China, 1988, Waltham A. C. , Smart P. L. ,
Karst landscapes, developed by solutional erosion of massive limestones, are characterized by underground drainage and the development of closed depressions. In tropical areas, with high solution rates, long uninterrupted periods of erosion and a lack of glacial planation, the expansion and deepening of these closed depressions creates a rugged relief dominated by either conical hills or steeper-sided towers. The form of the cones and towers is a function of both the carbonate lithology and the erosional history; the towers develop only in massive, mechanically strong, compact limestones where erosional planation and tectonic uplift have kept pace over a long period of time (Smart et al 1986). These karst landscapes are characteristic of huge areas of southern China, largely in the provinces of Guangxi and Guizhou (Fig. 1) and the spectacular scenery of the limestone has often been represented in classical Chinese painting. They are now also becoming a major tourist attraction, with Guilin, in Guangxi, frequently visited by Westerners. These terrains do, however, pose serious difficulties to the civil engineer. Where relief is not great, or where rates of uplift have been low, corridors of flatter ground have often been created by lateral planation at the water table. These corridors may be lithologically or structurally controlled, and form obvious routes through the karst. Where the relief is higher and the regional water table is not intersected, coalescence of the depressions to form flatter ground is rare, and road and rail development is more problematic. In order to avoid excessive and ... This 250-word extract was created in the absence of an abstract

The Source of the Jenolan River, 1988, Kiernan, Kevin

Geomorphological and Hydrological investigation of un-mapped limestone outcrops and enclosed depressions that occur between North Wiburds Bluff and the headwaters of Bindo Creek has confirmed the presence of significant karst well to the north of the boundary of the Jenolan Caves Reserve and that karst drainage could conceivably breach the Great Dividing Range. The limestone becomes progressively less well dissected northwards with the karst being very subdued at the northern end of the belt. Fluoroscein testing has shown that a streamsink at the southern end of this area drains directly to Central River in Mammoth Cave, and thence to imperial Cave and Blue Lake. This indicates that at least some of the limestone in this area is continuous beneath the surficial covers with the main Northern Limestone rather than being a discrete lens. The situation has important management implications in view of expanding forestry operations in the area since these have the potential to seriously increase the sediment load of waters that pass through wild caves and the Jenolan tourist caves complex.

Le karst nivernais : aperu gomorphologique et hydrogologique, 1989, Couturaud A. , Orange A.
The Nivre karst: geomorphologic and hydrogeologic considerations - Western part of Burgundy and southern part of the Paris basin, the Nivernais karst takes from both regions their lithologic and structural features: Middle and Upper Jurassic carbonate formations, monocline structure with horsts and grabens. But its particularity is in the thick superficial formations, that are supporting a wide mantle of forest, and that determine its morphology, its hydrodynamic and its hydrochemistry. The karst area is distinguished by closed depressions and by the abundance of valleys. The penetrable cavities are scarce and of a little extension, and are principally underground streams. The study of the hydrodynamic and the chemistry of some springs have shown the complexity and the variability of the dynamic of the karstic systems that depends essentially on the superficial formations.

Upper Sinking Cove, dissecting the eastern escarpment of the Cumberland Plateau, is characterized by a multiple aquifer, predominantly vadose hydrologic system with minor surface components. There is a central trunk channel along the axis of the cove and a network of independent tributaries. Aquitards within the limestones, particularly Hartselle Formation shales, have influenced both cave and surface landform development by perching ground waters and slowing the vertical growth of closed depressions. Long-term solutional denudation in the portion of the cove underlain by limestones (40 per cent) is an estimated 56 mm per 1000 years, suggesting that karst development began 15-16 million years ago. Despite lower soil CO2 and spring water hardness, 61 per cent of annual denudation occurs in the six winter months when 76 per cent of yearly runoff occurs. Landform development in Upper Sinking Cove appears to have begun as stream erosion carved a valley first in the sandstone caprock of the escarpment and later in the underlying Pennington Formation limestones containing numerous shale layers which promoted surface stream flow. Eventually stream erosion exposed the massive Bangor limestones which allowed deep ground water flow. Surface streams were pirated underground with the eventual formation of the chain of three closed depressions which constitute Upper Sinking Cove

The signature of karst terrain is a suite of characteristic landforms: caves, closed depressions, deranged surface drainage, and sculptured bedrock surfaces. Identification of karst, in reality, is accomplished by an ill-defined mix of morphological, sedimentological, and bedrock-geology evidence. The purely morphological signature depends on an examination of population statistics and the scaling laws for the various landforms. Caves are fragments of active and paleo conduit drainage systems. The distribution of cave lengths is a power function with a fractional (fractal) exponent. The number of closed depressions of given depth or diameter falls off exponentially with increasing size. Blind valley areas relate to stream length and stream order by power laws. Some features of bedrock sculpturing occur at fu;ed scale. Pinnacle karren, however, appear to be scale invariant over seven orders of magnitude of scale range

Karst Development and Speleogenesis, Isla de Mona, Puerto Rico, 1998, Frank, E. F. , Mylroie, J. , Troester, Jo. , Alexander, Jr. , E. C. , Carew, J.
Isla de Mona consists of a raised table-top Miocene-Pliocene reef platform bounded on three sides by vertical cliffs, up to 80 m high. Hundreds of caves ring the periphery of the island and are preferentially developed in, but not limited to, the Lirio Limestone/Isla de Mona Dolomite contact. These flank margin caves originally formed at sea level and are now exposed at various levels by tectonic uplift of the island (Frank 1983; Mylroie et al. 1995b). Wall cusps, a characteristic feature of flank margin caves, are ubiquitous features. Comparisons among similar caves formed in the Bahamas and Isla de Mona reveal the same overall morphology throughout the entire range of sizes and complexities. The coincidence of the primary cave development zone with the Lirio Limestone/Isla de Mona Dolomite contact may result from syngenetic speleogenesis and dolomitization rather than preferential dissolution along a lithologic boundary. Tectonic uplift and glacioeustatic sea level fluctuations produced caves at a variety of elevations. Speleothem dissolution took place in many caves under phreatic conditions, evidence these caves were flooded after an initial period of subaerial exposure and speleothem growth. Several features around the perimeter of the island are interpreted to be caves whose roofs were removed by surficial denudation processes. Several large closed depressions and dense pit cave fields are further evidence of surficial karst features. The cliff retreat around the island perimeter since the speleogenesis of the major cave systems is small based upon the distribution of the remnant cave sections.

Karst and caves in salt diapirs, SE Zagros Mts. (Iran), 1999, Bosá, K Pavel, Bruthans Jirí, , Filippi Michal, Svoboda Tomá, š, , Š, Mí, D Jakub

About 200 salt diapirs (plugs) have been known in the region of the Persian Gulf. numerous are still active. Karst rocks are represented by a rock salt, less frequently by gypsum and anhydrite. Karst developed especially in relics of planated surfaces. Karst forms are completely comparable with karsts in classical carbonate rocks. Different forms can be distinguished: karren, solution pipes, solution dolines, solution-collapse dolines, uvala-like to polje-like depressions, blind valleys, canyon-like forms, ponors, springs and caves. Two World longest caves in salt were discovered and explored here. Long caves are developed especially in a watertable, large ones in plugs near the seacoast. Caves are often outlets of closed depressions (polje-like). Some caves at bottoms of collapse-solution dolines or swallow holes are subvertical. Karst processes are caused dominantly by dissolution of salt, less frequently of gypsum. The process of subrosion of halite under gypcretes plays the main role. Deep circulation of meteoric waters was proved in some plugs.

Simulated effect of vadose infiltration on water levels in the Northern Guam Lens Aquifer, 2000, Contractor Dn, Jenson Jw,
Regional-scale hydrology of the fresh water lens in the Northern Guam Lens Aquifer has been simulated in the past using a finite element, sharp interface computer model, SWIG2D. Systematic differences exist between observed and computed water levels. Computed seasonal peak water levels are higher, and the computed seasonal lows are lower than the respective observed levels. It is hypothesized that vadose storage must store a substantial amount of water during the wet season and release it gradually into the lens during the dry season. Flow through the vadose zone was simulated with a one-dimensional finite element, unsaturated flow program UNSATID, in which the van Genuchten model is used to characterize unsaturated diffuse flow through the matrix of the vadose zone. An additional parameter (SINK) was added to the van Genuchten set to account for rapid infiltration down open pathways (fractures) associated with the closed depressions of the karst terrain. A global-optimization technique (Shuffled Complex Evolution or SCE-UA Method) was used to obtain the parameters that minimized the difference between simulated and observed water levels. Simulations incorporating the van Genuchten model were accomplished by combining the two programs, UNSATID and SWIG2D, into a single program. The sum-of-squared-errors (SSE) between computed and observed water levels in four observation wells was minimized using SCE-UA, reducing the arithmetically averaged SSE of the four wells by 30% compared with the SSE obtained when the vadose zone was not modeled. These results suggest that vadose storage is significant. On the other hand, the fact that the best fit obtained with an optimum parameter set was able to reduce the SSE by no more than 30% suggests that additional phenomena have yet to be accounted for to mon fully explain differences between simulated and observed well water levels. (C) 2000 Elsevier Science B.V. All rights reserved

Un karst sous la glace de l'Antarctide?, 2003, Bini A. , Forieri A. , Remy F. , Tabacco I. E. , Zirizzotti A. , Zuccoli L.
ARE THERE KARSTIC LANDFORMSUNDER ANTARCTICICECAP? - A new bedrock map of the Dome C area based on all radar data collected during Italian Antarctic Expeditions in 1995, 1997, 1999 and 2001 is presented. The map can clearly distinguish the Dome C plateau, along with some valleys and ridges develop. The plateau develops at three different altimetric levels and its morphology is characterised by hills and closed depressions. There are no visible features, which can be ascribed to glacial erosion or deposition. The major valley is 15 km wide and 500 m deep; its axis is parallel to that of other valleys and ridges in the plateau. The valley bottom is not flat, but contains a saddle in its centre. The morphology of the major valley could be considered as a relict one, which was not modified by the overlying ice cap. Two big ridges, characterised by hills, saddles and depressions, he near the boundaries of the area. The hill and depression landscape may be the result of two different processes the weathering of granitic rocks, with the development of a Demi-oranges and inselberg landscape, or the karstification of limestones, and development of a cone karst. The karstic hypothesis should be the more suitable, but it is impossible to exclude the granitic rock weathering. Both proposed genetic hypotheses calling for a warm- humid climate and a long period of stability in a continental environment. Consequently, the ice cap did not largely modify the landscape.

Distribution, morphology, and origins of Martian pit crater chains, 2004, Wyrick D. , Ferrill D. A. , Morris A. P. , Colton S. L. , Sims D. W. ,
Pit craters are circular to elliptical depressions found in alignments (chains), which in many cases coalesce into linear troughs. They are common on the surface of Mars and similar to features observed on Earth and other terrestrial bodies. Pit craters lack an elevated rim, ejecta deposits, or lava flows that are associated with impact craters or calderas. It is generally agreed that the pits are formed by collapse into a subsurface cavity or explosive eruption. Hypotheses regarding the formation of pit crater chains require development of a substantial subsurface void to accommodate collapse of the overlying material. Suggested mechanisms of formation include: collapsed lava tubes, dike swarms, collapsed magma chamber, substrate dissolution ( analogous to terrestrial karst), fissuring beneath loose material, and dilational faulting. The research described here is intended to constrain current interpretations of pit crater chain formation by analyzing their distribution and morphology. The western hemisphere of Mars was systematically mapped using Mars Orbiter Camera (MOC) images to generate ArcView(TM) Geographic Information System (GIS) coverages. All visible pit crater chains were mapped, including their orientations and associations with other structures. We found that pit chains commonly occur in areas that show regional extension or local fissuring. There is a strong correlation between pit chains and fault-bounded grabens. Frequently, there are transitions along strike from ( 1) visible faulting to ( 2) faults and pits to ( 3) pits alone. We performed a detailed quantitative analysis of pit crater morphology using MOC narrow angle images, Thermal Emission Imaging System (THEMIS) visual images, and Mars Orbiter Laser Altimeter (MOLA) data. This allowed us to determine a pattern of pit chain evolution and calculate pit depth, slope, and volume. Volumes of approximately 150 pits from five areas were calculated to determine volume size distribution and regional trends. The information collected in the study was then compared with non-Martian examples of pit chains and physical analog models. We evaluated the various mechanisms for pit chain development based on the data collected and conclude that dilational normal faulting and sub-vertical fissuring provide the simplest and most comprehensive mechanisms to explain the regional associations, detailed geometry, and progression of pit chain development

Gypsum karst in the Crotone province (Calabria, Southern Italy), 2005, Parise Mario, Trocino Antonio

The Calabria region of southern Italy presents remarkable examples of gypsum karst, involving evaporite rocks ranging in age from Trias to Miocene. Triassic evaporites are limited to a sequence of about one hundred meters of thickness in the Coastal Chain, on the western Calabrian coast. Messinian evaporites, on the other hand, extensively crop out to the east, in the Crotone Basin. The present contribution intends to describe the main features of gypsum karst in the latter area, from the surface karst morphology to the development of caves. The Crotone Basin is among the most interesting areas as regards evaporite karst in Italy: a variety of surface karst landforms is there present, including dolines, blind valleys, closed depressions, and deep and narrow canyons intensely affected by slope movements. Many caves are located at the bottom of the dolines, as Grave Grubbo which, with a length over 2,500 meters, is one of the longest Italian caves in evaporites. The study area has experienced several transformations, mostly due to agricultural activity and to scarce attention paid by local administrators toward this unique naturalistic landscape. The high value of Calabrian gypsum karst is thus not fully exploited, and several cases of degradation of the caves have been registered, even with consequences for the quality of water flowing in the karst systems.

Fields of multi-kilometer scale sub-circular depressions in the Carnegie Ridge sedimentary blanket: Effect of underwater carbonate dissolution?, 2005, Michaud F. , Chabert A. , Collot J. Y. , Sallares V. , Flueh E. R. , Charvis P. , Graindorge D. , Gustcher M. A. , Bialas J.

Offshore Ecuador, the Carnegie Ridge is a volcanic ridge with a carbonate sediment drape. During the SALIERI Cruise, multibeam bathymetry was collected across Carnegie Ridge with the Simrad EM120 of the R/V SONNE. The most conspicuous features discovered on the Carnegie Ridge are fields of circular closed depressions widely distributed along the mid-slope of the northern and southern flanks of the ridge between 1500 and 2600 m water depth. These circular depressions are 1–4 km wide and typically 100–400 m deep. Most are flat floored and some are so densely packed that they form a honeycomb pattern. The depressions were carved into the ridge sedimentary blanket, which consists of carbonate sediment and has been dated from upper Miocene to upper Pleistocene. Several hypotheses including pockmark origin, sediment creeping, paleo-topography of the volcanic basement, effects of subbottom currents, and both marine and subaerial karstic origins are discussed. We believe that underwater dissolution process merits the most serious consideration regarding the origin of the closed depression.

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