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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 exoskeleton is an external skeleton. the hard body covering or shell of most invertebrate animals, including insects, crayfish, and millipedes [23].?

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 expression (Keyword) returned 46 results for the whole karstbase:
Showing 1 to 15 of 46
A New Equation Solver for Modeling Turbulent Flow in Coupled Matrix‐Conduit Flow Models, ,

Karst aquifers represent dual flow systems consisting of a highly conductive conduit system embedded in a less permeable rock matrix. Hybrid models iteratively coupling both flow systems generally consume much time, especially because of the nonlinearity of turbulent conduit flow. To reduce calculation times compared to those of existing approaches, a new iterative equation solver for the conduit system is developed based on an approximated Newton–Raphson expression and a Gauß–Seidel or successive over-relaxation scheme with a single iteration step at the innermost level. It is implemented and tested in the research code CAVE but should be easily adaptable to similar models such as the Conduit Flow Process for MODFLOW-2005. It substantially reduces the computational effort as demonstrated by steady-state benchmark scenarios as well as by transient karst genesis simulations. Water balance errors are found to be acceptable in most of the test cases. However, the performance and accuracy may deteriorate under unfavorable conditions such as sudden, strong changes of the flow field at some stages of the karst genesis simulations.

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Detailed tectonic trends on the central part of the Hellenic Outer Ridge and in the Hellenic Trench System, 1982, Kenyon N. H. , Belderson R. H. , Stride A. H. ,
Extensive new sonograph coverage in the Eastern Mediterranean allows a re-assessment of the complex relief outside the Hellenic Arc. The trenches to the SE and SW of Crete are similar in their plan view appearance, each having predominantly sinuous or curved structures that are interpreted as the surface expression of major thrusts. Thrusting, possibly imbricate, is also suggested on the central, shallowest part of the Hellenic Outer Ridge where interlocking convex-outward, curved structures occur, along with other faults and folds. These are thought to relate to decollement-type displacement within or beneath evaporite sediments. The structural style deduced from the morphology is consistent with a continuing outward radial push of the Hellenic Arc to the SW, S and SE, rather than with a migration to the SW and strike-slip on the SE side of the arc as proposed by other workers

Subsidence and foundering of strata caused by the dissolution of Permian gypsum in the Ripon and Bedale areas, North Yorkshire, 1986, Cooper Ah,
Underground dissolution of thick gypsum beds in the Edlington Formation and Roxby Formation of the Zechstein sequence in North Yorkshire, England, has resulted in a 3 km-wide and 100 km-long belt of ground susceptible to foundering. Within this belt a large subsidence depression at Snape Mires, near Bedale, was largely filled with lacustrine deposits in the later part of the Late Devensian and during the Flandrian. South of Snape Mires the Nosterfield-Ripon-Bishop Monkton area has suffered about 40 episodes of subsidence in the past 150 years, and the presence of several hundred other subsidence hollows indicates considerable activity from the later part of the Devensian onwards. The linear and grid-like arrangement of these subsidence hollows indicates collapse at intersections in a joint-controlled cave system. Linear subsidence features at Snape Mires are also joint-controlled. The transition from anhydrite at depth to secondary gypsum near surface marks the down-dip limit of the subsidence-prone belt. Cavities are propagated upwards by roof collapse of caverns in the gypsum, leading to the formation of breccia pipes. Choking of the pipes can reduce the surface expression of the underground collapse, but the larger cavities are liable to produce pipes that reach the surface even at the eastern boundary of the 3 km-wide belt described. Further subsidence in the Ripon area is predicted and some suggestions for remedial measures are given

Sport and Scout Caving - The Present Dilemma, 1987, Crabb, Evalt

This paper traces the evolution of organised caving as a post World War 2 phenomenon, and the changes in practice and attitude that have occurred. These practices are contrasted against stated behavioural codes. Parallel to this, the development of caving as a scouting activity is discussed, with reference to the general principles and practices of scouting. The author has been working toward evolving policies and practices within scouting which are consistent with the needs of conservation and the underlying philosophies of scouting. Implementation of these attitudes in one area is fully detailed, with some comment on the success and acceptability of the program. This training program is contrasted against the foreshadowed N.S.W. Branch Policy on Rock-Related Activities. The sequential discussion highlights some weaknesses within clubs and A.S.F., particularly in our methods of communication. There are no firm proposals, but possible directions for future discussions are indicated. It is the intention of this paper to give a historical perspective to some of the present perceived conflicts; in reality, the only conflict is between our oft-expressed aim of conservation of caves (i.e. safeguard the karst heritage of Australia), and our visible activity - use of caves for recreational activity. Both the intensity of expression of our concern, and lessening of self-constraint on recreational activity have greatly magnified with time; we are fast approaching a 'crossroads' scenario where our credibility is at great risk.

Upper Ordovician Arthur Marble and Oligocene Takaka Limestone contain extensive phreatic cave systems beneath the Takaka valley and Golden Bay. Half of all water flows in the Takaka valley pass through subterranean drainage conduits in carbonate rock. New Zealand's largest freshwater springs, the Waikoropupu Springs, are one surface expression of these karst systems. Other characteristics are dolines and submarine springs. A paleocave system developed in the Arthur Marble during the formation of the northwest Nelson peneplain in the Late Cretaceous and early Tertiary. Subsequent subsidence of the peneplain, and deposition of Motupipi Coal Measures, Takaka Limestone, and Tarakohe Mudstone, was followed by folding and faulting of the sequence in the Kaikoura Orogeny. Uplift and erosion in the Pleistocene brought the two carbonate rock formations within reach of groundwater movements. The paleocave system in Arthur Marble was reactivated during periods of glacial, low sea levels, and a smaller cave system formed in the overlying Takaka Limestone. Both systems interact and extend to more than 100 m below present sea level, forming the Arthur Marble - Takaka Limestone aquifer

This paper argues that southern Africa was a remote part of the Old World in the late Pleistocene (125-10 ka ago). Because of this isolated position there was continuity without significant replacement in the resident population. Isolation and the relatively recent spread of agriculture to the region has allowed a section of this population to survive into the present. They are the Bushmen (San). Studies of geographic patterning in conventional genetic markers and mitochrondrial DNA indicate that the Bushman clade has a long evolutionary history in southern Africa. Estimates of more than 100 ka for the continued presence of this population in the region are supported in archaeological investigations of sites with long sequences such as Klasies River main site and Border Cave. Human remains dating to the earlier part of the late Pleistocene have been recovered from these sites and the samples form a morphological series with the Klasies River remains possibly 20 ka older than those from Border Cave. There is no fossil record for the later Pleistocene, however, at a period when selection for a gracile morphology may have been pronounced. The cultural associations in the earlier late Pleistocene are with the Middle Stone Age. Expressions of cultural 'style' and the occurrence of similar artefact design types in the Middle and Later Stone Ages can be interpreted with reference to the ethnographic present. Temporal continuity can be shown in the geographical distribution of stylistic markers and this suggests participation in a shared cognitive system. The inference is that the people in the earlier late Pleistocene had cognitive abilities that are comparable to those shown by their Holocene and modern descendants. The presence of the ancestors of a modern population in the earlier late Pleistocene in this region is perhaps expected if modern people had their origins in Africa

High-resolution seismic expression of karst evolution within the Upper Floridan aquifer system; Crooked Lake, Polk County, Florida, 1994, Evans Mw, Snyder Sw, Hine Ac,

We collected 43 km of high resolution seismic reflection profiles from a 14.5-hectare lake in the central Florida sinkhole district and data from three adjacent boreholes to determine the relationship between falling lake levels and the underlying karst stratigraphy. The lake is separated from karstified Paleogene to early Neogene carbonates by 65-80 m of siliciclastic sands and clays. The carbonate and clastic strata include three aquifer systems separated by clay-confining units: a surficial aquifer system (fine to medium quartz sand in the upper 20-30 m), the 25-35 m thick intermediate aquifer system (in Neogene siliciclastics), and the highly permeable upper Floridan aquifer system in Paleogene to early Neogene limestones. Hydraulic connection between these aquifer systems is indicated by superjacent karst structures throughout the section. Collapse zones of up to 1000 m in diameter and > 50 m depth extend downward from a prominent Middle Miocene unconformity into Oligocene and Upper Eocene limestones. Smaller sinkholes (30-100 m diameter, 10-25 m depth) are present in Middle to Late Neogene clays, sands, and carbonates and extend downward to or below the Middle Miocene unconformity. Filled and open shafts (30-40 m diameter; 10-25 m depth) ring the lake margin and overlie subsurface karst features. The large collapse zones are localized along a northeast-southwest line in the northern ponds and disrupt or deform Neogene to Quaternary strata and at least 50 m of the underlying Paleogene carbonate rocks. The timing and vertical distribution of karst structures are used to formulate a four-stage model that emphasizes stratigraphic and hydrogeologic co-evolution. (1) Fracture-selective shallow karst features formed on Paleogene/early Neogene carbonates. (2) Widespread karstification was limited by deposition of Middle Miocene clays, but vertical karst propagation continued and was focused because of the topographic effects of antecedent karst. (3) Groundwater heads, increase with the deposition of thick sequences of clastics over the semipermeable clays during Middle and Late Neogene time. The higher water table and groundwater heads allowed the accumulation of acidic, organic-rich soils and chemically aggressive waters that percolated down to Paleogene carbonates via localized karst features. (4) After sufficient subsurface dissolution, the Paleogene carbonates collapsed, causing disruption and deformation of overlying strata. The seismic profiles document an episodic, vertically progressive karst that allows localized vertical leakage through the clay-confining units. The spatial and temporal karst distribution is a result of deposition of sediments with different permeabilities during high sea levels and enhanced karst dissolution during low sea levels. Recent decreases in the potentiometric elevation of the Floridan Aquifer System simulates a sea-level lowstand, suggesting that karst dissolution will increase in frequency and magnitude

The hydro-electric power plant (HEPP) which will exclusively use water from a karst underground storage basin will be built in the vicinity of the abundant karst spring Ombla in Croatia. This paper presents the results obtained by hydrogeologic, hydrologic and hydraulic investigations related to the principles of ground water circulation in the karst. The analyses included the determination of the effective porosity n(e) of the karst aquifer and the definition of the volume of large conduits and small fractures in the karst which form the aquifer volume. The position and dimensions of large karst conduits have also been defined. It was established that in three small springs, Zaton, Zavrelje and Slavljan, water overflows from the Ombla Spring in periods of high ground water levels, It was also discovered that at certain periods the Dupuit expression for steady-state flow in an unconfined aquifer can be used. In accordance with this, it was possible to determine the values of hydraulic conductivity, K (in m s(-1)), for the Ombla aquifer. They range from 2 x 10(-3) to 5 x 10(-3) m s(-1) and are inversely proportional to the Ombla Spring discharge. Continuous measurements of the ground water level by several piezometers located in the karst hinterland of the Ombla Spring and simultaneous measurement of the discharge made it possible to define discharge curves of the Ombla Spring dependent upon the ground water levels at Various locations. Characteristic features of the discharge curves made the identification of the position and dimensions of the main karst conduits possible

Principles of early development of karst conduits under natural and man-made conditions revealed by mathematical analysis of numerical models, 1996, Dreybrodt W,
Numerical models of the enlargement of primary fissures in limestone by calcite aggressive water show a complex behavior. If the lengths of the fractures are large and hydraulic heads are low, as is the case in nature, dissolution rates at the exit of the channel determine its development by causing a slow increase of water flow, which after a long gestation time by positive feedback accelerates dramatically within a short time span. Mathematical analysis of simplified approximations yields an analytical expression for the breakthrough time, when this happens, in excellent agreement with the results of a numerical model. This expression quantifies the geometrical, hydraulic, and chemical parameters determining such karat processes. If the lengths of the enlarging channels are small, but hydraulic heads are high, as is the case for artificial hydraulic structures such as darns, it is the widening at the entrance of the flow path which determines the enlargement of the conduit. Within the lifetime of the dam this can cause serious water losses, This can also be explained by mathematical analysis of simplified approximations which yield an analytical threshold condition from which the safety of a dam can be judged. Thus in both cases the dynamic processes of karstification are revealed to gain a deeper understanding of the early development of karst systems. As a further important result, one finds that minimum conditions, below which karstification cannot develop, do not exist

Influence of climatic parameters in karstic denudation, 1997, Gombert P. ,
Karstic denudation is empirically estimated by specific dissolution or geochemical balance calculations, which need a precise knowledge of the aquifer, or by mathematical expressions which only depend upon rainfall. It is in fact known that water inflow charged with CO2 is the main karstic agent. We propose a mathematical model called << Maximal Potential Dissolution >> (DMP) and based on efficient infiltration calculation, CO2 soil productivity and knowledge of the calcocarbonic equilibrium

Mapping Chicxulub crater structure with gravity and seismic reflection data, 1998, Hildebrand A. R. , Pilkington M. , Ortizaleman C. , Chavez R. E. , Urrutiafucugauchi J. , Connors M. , Granielcastro E. , Camarazi A. , Halpenny J. F. , Niehaus D. ,
Aside from its significance in establishing the impact-mass extinction paradigm, the Chicxulub crater will probably come to exemplify the structure of large complex craters. Much of Chicxulub's structure may be mapped' by tying its gravity expression to seismic-reflection profiles revealing an [~]180 km diameter for the now-buried crater. The distribution of karst topography aids in outlining the peripheral crater structure as also revealed by the horizontal gradient of the gravity anomaly. The fracturing inferred to control groundwater flow is apparently related to subsidence of the crater fill. Modelling the crater's gravity expression based on a schematic structural model reveals that the crater fill is also responsible for the majority of the negative anomaly. The crater's melt sheet and central structural uplift are the other significant contributors to its gravity expression. The Chicxulub impact released [~]1.2 x 1031 ergs based on the observed collapsed disruption cavity of [~]86 km diameter reconstructed to an apparent disruption cavity (Dad) of [~]94 km diameter (equivalent to the excavation cavity) and an apparent transient cavity (Dat) of [~]80 km diameter. This impact energy, together with the observed [~]2 x 1011 g global Ir fluence in the Cretaceous-Tertiary (K-T) fireball layer indicates that the impactor was a comet estimated as massing [~]1.8 x 1018 g of [~]16.5 km diameter assuming a 0.6 gcm-3 density. Dust-induced darkness and cold, wind, giant waves, thermal pulses from the impact fireball and re-entering ejecta, acid rain, ozone-layer depletion, cooling from stratospheric aerosols, H2O greenhouse, CO2 greenhouse, poisons and mutagens, and oscillatory climate have been proposed as deleterious environmental effects of the Chicxulub impact with durations ranging from a few minutes to a million years. This succession of effects defines a temperature curve that is characteristic of large impacts. Although some patterns may be recognized in the K-T extinctions, and the survivorship rules changed across the boundary, relating specific environmental effects to species' extinctions is not yet possible. Geochemical records across the boundary support the occurrence a prompt thermal pulse, acid rain and a [~]5000 year-long greenhouse. The period of extinctions seems to extend into the earliest Tertiary

Geophysical Studies at Kartchner Caverns State Park, Arizona, 1999, Lange, A. L.
Geophysical studies over Kartchner Caverns State Park mapped structure and groundwater patterns beneath valley alluvium and determined the geophysical expression of the caverns at the surface. Three techniques were employed: electromagnetics (EM), gravity, and natural potential (NP). Electromagnetic traverses in the area failed to detect the voids, owing to the very low conductivity of the carbonate rock. On the other hand, the EM method succeeded in defining the boundary between carbonate rock and alluvium, and in detecting the high-conductivity underflow beneath the drainage system. Resolution of the gravity survey over outcrop was limited to ~0.1 mgal, due to severe terrain effects. Nevertheless, two of the three major cavern passages were expressed as gravity lows at the surface, and fifteen additional small gravity anomalies could be the effect of fracture zones or unexposed caves. East of the carbonate block, the gravity profiles delineated the range-front fault and afforded interpretations of bedrock structure beneath valley fill. Natural-potential profiles, coincident with those of the gravity survey, produced a prominent compound anomaly over the mapped caverns. The 55 mV NP high was flanked by broad lows measuring ~15 mV over two of the main cavern galleries. The high was incised by a third low over a middle passage of the caverns. The lows are tentatively attributed to filtration downward toward the cave ceilings; the highs, to evapotranspiration from a deeper groundwater reservoir. Elsewhere over the outcrop, continuous NP trends are the likely expressions of faulting and fracturing, possibly accompanied by solution activity

Agriculture, landscape and human impact in some karst areas of Italy, 1999, Burri Ezio, Castiglioni Benedetta, Sauro Ugo
Italy is made up for about 1/5 of its surface by soluble rocks, which represent the arena of karst environments. The karst morpho-units, some hundreds, are mainly distributed inside the alpine structure of the Mediterranean mountains. A very large number of rock formations are present, different in facies, lithology, age, etc. Among these, carbonate rocks prevail, followed by gypsum and salt. Most of the carbonate rocks are limestones sedimented in a platform environment and they show a wide range of porosity, frequency of fractures and bedding planes. The climatic processes, the expression of some different sub-types of Mediterranean climate (from the typical Mediterranean to sub-atlantic and sub-continental varieties), are the main control of the recent morphodynamics inside the karst morpho-units. In some areas the variability of precipitation is very high. The soil-water deficit during summer, together with the steep slopes, makes these environments highly vulnerable to human impact, especially in relation to soil use for grazing and agriculture. The soils, with enriched mineral contents from the fall of loess-like sediments or of volcanic ashes, were surely very appealing to the first farmers.

Landscape evolution and the preservation of tectonic landforms along the northern Yammouneh Fault, Lebanon, 1999, Butler Rwh, Spencer S,
The Yammouneh Fault is commonly considered to be the principal active strand of the Dead Sea Transform in Lebanon -- an inference reached primarily from interpretations of the geomorphological expression of the fault on satellite images. However, new geological field observations show the Yammouneh Fault to be sealed stratigraphically by the Homs Basalt, dated using new K-Ar ages at 5.2-6.5 Ma. Drainage systems which link to the pre-Homs Basalt palaeosurface show evidence of fault disruption. Those valleys incised into the basalt show no evidence for transcurrent offsets. The inferred left-lateral displacement of c. 45 km on the Dead Sea Transform that post-dates the Homs Basalt is presumed to have bypassed to the west of Mount Lebanon. These linked geological and geomorphological studies indicate that landscape evolution can be exceptionally slow in northern Lebanon. Faceted spurs, poljes and offset drainage along the Yammouneh Fault across Mount Lebanon, evident on satellite images, are interpreted as being of Miocene age and are not indicative of Plio-Quaternary displacements on the fault. Much of the Lebanese tectonic landscape has thus remained stable for many millions of years, although locally incised during large-scale uplift of the Mount Lebanon range. Presumably landscape insensitivity reflects the arid climatic conditions together with inhibited run-off due to the regional karst system

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