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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 backwater curve is water surface profile in a stream or channel above a constriction or impoundment [16].?

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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 cap rock (Keyword) returned 12 results for the whole karstbase:
Cavern Development in the Dimensions of Length and Breadth. PhD Thesis, 1982, Ewers, Ralph Owen

Three conceptual models are proposed for the integration of the large systems of conduits responsible for groundwater flow in soluble rocks. These models are supported by laboratory experiments with scaled solution models, flow-field analogues, and evidence from existing caves.
The three models reflect different boundary conditions imposed by geologic structure and stratigraphy. They have three characteristics in common. First, the smaller elements of the larger systems propagate separately from points of groundwater input toward points of discharge as distributary networks. Second, the integration of the smaller networks proceeds headward from the resurgence, in a stepwise fashion. Third, the result of the integration process in each case is a tributary system with many inputs discharging through a single discharge point.
The potential for growth of each of the smaller networks, within a common pressure field, is related to its distance from the discharge boundary and the distribution of other inputs. The first input to establish a low-resistance link to the discharge boundary will effect a localized depression within the potential field, thus attracting the flow and redirecting the growth of nearby networks until they eventually link with it. As additional orders of links develop, the system takes on a tributary pattern.
The first model applies to steeply dipping rocks. Inputs occur where bedding planes are truncated by erosion, and discharge takes place to the strike. Conduits in this case evolve as a roughly rectangular grid of strike and dip oriented elements. Dip elements are the initial form, with subsequent integration along the strike. The type example is the Holloch in Switzerland.
The second model applies to flat-lying rocks. Inputs occur over a broad area, and discharge takes place along a linear boundary. Conduits in this case evolve in a trellised array with elements normal to the discharge boundary predating those parallel to it. These latter conduits integrate the flow. The type example is the Mammoth Cave Region, Kentucky.
The third model applies to simple systems which occur beneath an impermeable cap rock. Inputs occur where erosion has breached the capping beds. The type example is Cave Creek, Kentucky.


RELATIONSHIP BETWEEN FRACTURES AND KARSTIFICATION - THE OIL-BEARING PALEOKARST OF ROSPO MARE (ITALY), 1994, Soudet H. J. , Sorriaux P. , Rolando J. P. ,
The Rospo Mare oil field is located in the Adriatic Sea, 20 km off the Italian coast. The reservoir lies at a depth of 1300 m and consists of a paleokarst oi Oligocene to Miocene age which developed within Cretaceous limestones, now covered by 1200 m of Mio-Pliocene sequences. The oil column is about 140 m 8 high. The karstic nature of the reservoir was identified through vertical, cored drill holes which allowed us to analyse the various solution features and the sedimentary infilling (speleothems, terra rossa, marine clays), as well as their vertical distribution. Erosion morphology at the top of the karst is highly irregular, including in particular paleovalleys as well as many pit-shaped sink holes. Detailed geophysical knowledge of that morphology helped to optimize the development of the field through horizontal drilling. Observations concerning the upper part of the reservoir were compared to a palaeokarst of the same age, outcropping widely onshore, in quarries located nearby. The Rospo Mare paleokarst is an integral part of the ante Miocene paleokarst assemblages of the periphery of the Mediterranean which were formed in tropical conditions. Only the fractures enhanced by meteoric water during the formation of the karat are important for reservoir connectivity. During the formation of the karst there were several phases of dissolution and infilling which modified the geometry of the open fissures and only these fractures play an important role in the reservoir drainage. Vertically we can distinguish three very different zones from top to bottom: at the top the epikarst (0-35 m) in a zone of extension. All the fractures have been enlarged by dissolution but the amount of infilling by clay is substantial. The clays are derived either from alteration of the karat fabric or by deposition during the Miocene transgression; the percolation zone (15-45 m) is characterized by its network of large fractures vertically enlarged by dissolution which corresponds to the relict absorption zones in the paleokarst. These fractures, which usually have a pluridecametric spacing, connect the epi-karst with the former sub-horizontal river system. This zone has been intersected by the horizontal wells during the field development. In this zone there are local, horizontal barriers oi impermeable clay which can block vertical transmissibility. In these low permeability zones the vertical fractures have not been enlarged due to dissolution hence the horizontal barrier; the zone of underground rivers (35-70 m) is characterized by numerous horizontal galleries which housed the subterranean ground water circulation. When these fissures are plurimetric in extent this can lead to gallery collapse with the associated fill by rock fall breccia. This can partly block the river system but always leaves a higher zone of free circulation with high permeabilities of several hundreds of Darcys. These galleries form along the natural fracture system relative to the paleohydraulic gradient which in some cases has been preserved. The zone below permanent ground water level with no circulation of fluids is characterized by dissolution limited to non-connected vugs. Very locally these fissures can be enlarged by tectonic fractures which are non-connected and unimportant for reservoir drainage. Laterally, only the uppermost zone can be resolved by seismic imaging linked with horizontal well data (the wells are located at the top of the percolation zone). The Rospo Mare reservoir shows three distinct horizontal zones: a relict paleokarst plateau with a high index of open connected fractures, (area around the A and B platforms); a zone bordering the plateau (to the north-east of the plateau zone) very karstified but intensely infilled by cap rock shales (Miocene - Oligocene age); a zone of intensely disturbed and irregular karst paleotopography which has been totally infilled by shales. The performance of the production wells is dependent on their position with respect to the three zones noted above and their distance from local irregularities in the karst paleotopography (dolines, paleovalleys)

SPELEOGENESIS IN AEOLIAN CALCARENITE - A CASE-STUDY IN WESTERN VICTORIA, 1994, White S. ,
Most studies of karst landscapes and their processes have been concerned with consolidated, often well-jointed limestones. There are particular problems involved in the study of karst procesess in softer, less-compact limestones such as chalk, coral reefs, and aeolian calcarenite. Previous studies in aeolian calcarenite indicated these problems and a scheme was developed of speleogenesis in aeolian calcarenite. A study of karst processes in aeolian calcarenite at Bats Ridge in western Victoria has developed this scheme further. The karst features and processes at Bats Ridge are an integral part of the landscape of a mid-Pleistocene calcarenite dune system. The resolution of problems of the rapid subaerial speleogenesis in the area is achieved by the synthesis of the known karst features of the ridge and the geology and geomorphology of the area. Karst development on this aeolianite ridge depends on lithological conditions as well as the availability of aggressive water capable of solution. The diagenesis of the calcarenite is occurring now and must have been occurring by the mid-Pleistocene. This simultaneous lithification of the carbonate dunes into aeolian calcarenite rock and the development of solutional karst features in the dunes is the characteristic feature of the speleogenesis in this area. It is the formation of a hardened kankar layer (cap rock) in the dunes of sufficient compressive and tensile strength to support cavities, which is the result of these interrelated factors, that has strongly determined the formation of the karst features

SEDIMENT-HOSTED GOLD MINERALIZATION IN THE RATATOTOK DISTRICT, NORTH SULAWESI, INDONESIA, 1994, Turner S. J. , Flindell P. A. , Hendri D. , Hardjana I. , Lauricella P. F. , Lindsay R. P. , Marpaung B. , White G. P. ,
The Ratatotok district in the Minahasa Regency of North Sulawesi, Indonesia is an area of significant gold mineralisation. Gold has been mined in the district since at least the 1850s, and intensively by the Dutch between 1900 and 1921 with a recorded production of 5,060 kg of gold. Newmont began exploring the district in 1986, and has delineated a major sediment-hosted replacement-style deposit at Mesel, and other smaller deposits in an 8 X 5 km area. A total drill-indicated resource of over 60 metric tonnes of gold ( 2 Moz) is reported for Mesel, and three of the smaller deposits. Approximately 80% of this resource is refractory. Silver grades are usually low (< 10 g/t). The Mesel deposit is similar to many Carlin-type deposits in carbonate hostrocks, alteration, geochemical signature and ore mineralogy, but is distinct in tectonic setting. The discovery of replacement-style mineralisation at Mesel, in an impure limestone within a Tertiary island arc environment, demonstrates that deposits with outward characteristics similar to Carlin-type mineralisation are not restricted to a continental setting. Carbonate sediments in the Ratatotok district were deposited in a Late Miocene restricted basin. Later compressional tectonics caused uplift that resulted in karst development in the limestone and erosion of the adjacent volcanic arc with deposition of a thick epiclastic unit. This was followed by intrusion of shallow level pre-mineral andesite into the sequence. Mineralisation at Mesel, and probably elsewhere in the district, is synchronous with the late-stage reactivation of strike-slip faults. Mineralising fluids at Mesel were focussed along steep structures sympathetic to these faults, and trapped below a relatively impermeable andesite cap rock. Hydrothermal fluids caused decalcification of the silty, more permeable carbonate units with the formation of secondary dolomite, deposition of fine arsenian pyrite, silica veinlets and gold. Volume loss due to decalcification and dolomite formation caused collapse brecciation which enhanced fluid flow and further mineralisation. This locally culminated in total decarbonation and deposition of massive silica. Late-stage stibnite occurs in structural zones within the ore deposit, whereas arsenic (as realgar and orpiment) and mercury (as cinnabar) are concentrated on the periphery. Elsewhere in the Ratatotok district, gold mineralisation is restricted to replacement-style mineralisation in permeable zones along limestone-andesite contacts, open-space-filling quartz-calcite veins and stockworks, and residual quartz-clay breccias. The residual breccias are developed in-situ, and are interpreted to form by dissolution of the wallrock limestone from around pre-existing mineralisation. This has resulted in widespread eluvial gold occurrences

Hydrology and denudation rates of halite karst, 1994, Frumkin A,
Salt karst terrains exist mainly in arid climates where rock salt outcrops may escape complete destruction by dissolution. Such is the case with Mount Sedom, on the SW shore of the Dead Sea, one of the most arid parts of Israel. Many small catchments developed over the relatively insoluble cap rock which overlies the highly soluble rock salt. The catchments were surveyed and classified. Some 57% of the surface area is drained by an underground karst system. Water samples from various points in the system were analysed, and water development was inferred. Waters in cave conduits do not reach saturation during flood flow, unless the water is ponded for at least several hours. Based on the available evidence, regional karst denudation is tentatively estimated to be about 0.5-0.75 mm year-1, occurring mainly within the rock salt

RAPID ENTRENCHMENT OF STREAM PROFILES IN THE SALT CAVES OF MOUNT SEDOM, ISRAEL, 1995, Frumkin A, Ford Dc,
Rock salt is approximately 1000 times more soluble than limestone and thus displays high rates of geomorphic evolution. Cave stream channel profiles and downcutting rates were studied in the Mount Sedom salt diapir, Dead Sea rift valley, Israel. Although the area is very arid (mean annual rainfall approximate to 50 mm), the diapir contains extensive karst systems of Holocene age. In the standard cave profile a vertical shaft at the upstream end diverts water from a surface channel in anhydrite or elastic cap rocks into the subsurface route in the salt. Mass balance calculations in a sample cave passage yielded downcutting rates of 0.2 mm s(-1) during peak flood conditions, or about eight orders of magnitude higher than reported rates in any limestone cave streams. However, in the arid climate of Mount Sedom floods have a low recurrence interval with the consequence that long-term mean downcutting rates are lower: an average rate of 8.8 mm a(-1) was measured for the period 1986-1991 in the same sample passage. Quite independently, long-term mean rates of 6.2 mm a(-1) are deduced from C-14 ages of driftwood found in upper levels of 12 cave passages. These are at least three orders of magnitude higher than rates established for limestone caves. Salt cave passages develop in two main stages: (1) an early stage characterized by high downcutting rates into the rock salt bed, and steep passage gradients; (2) a mature stage characterized by lower downcutting rates, with establishment of a subhorizontal stream bed armoured with alluvial detritus. In this mature stage downcutting rates are controlled by the uplift rate of the Mount Sedom diapir and changes of the level of the Dead Sea. Passages may also aggrade. These fast-developing salt stream channels may serve as full-scale models for slower developing systems such as limestone canyons

Thickness of cap rock and other important factors affecting the morphogenesis of salt karst, 2000, Bruthans Jirí, , Š, Mí, D Jakub, Filippi Michal, Zeman Ondrej

Four classes of different thickness of cap rock can be distinguished, each with its special superficial and underground karst forms: 1. salt outcrops, 2. thin cap rock (0,5-2 m), 3. cap rock of moderate thickness (5-30 m), 4. cap rock of great thickness (more than 30 m). The most important factors affected by cap rock thickness are as follows: the density of recharge points, the amounts of concentrated recharge which occur at each recharge point, the rate of lowering the ground surface of salt karst, the dissolution capacity of water and the size and amount of load transported by underground flood-streams into cave systems. The thickness of cap rock above the cave does not influence the cave itself; more important seems to be the thickness of cap rock in the recharge area of the cave and the type of recharge into the salt environment. Another important factor is the thickness of overburden above the cave, which negatively correlates with intensity of breakdown. Wide passages in some caves are developed as result of intensive deposition of bedload, which expel the stream into the side of the passage and are due to enhanced corrosion in the few decimetres high zone above the bottom of passage.


Petrography of Finely Crystalline Cenozoic Dolostones as Revealed by Backscatter Electron Imaging: Case Study of the Cayman Formation (Miocene), Grand Cayman, British West Indies, 2003, Jones Brian, Luth Robert W. ,
Finely crystalline Cenozoic island dolostones, like those found in the Cayman Formation on Grand Cayman, are commonly assumed to be petrographically and compositionally homogeneous. Backscatter electron images (BSEI), however, show that the constituent dolomite crystals (< 100 {micro}m long and commonly < 20 {micro}m long) are commonly zoned with respect to their mol % CaCO3 content. Moreover, such images allow (1) depiction of growth patterns in the constituent crystals, irrespective of their origin, (2) recognition of replacive dolomite as opposed to dolomite cement, and (3) delineation of 'stratigraphic packages' in the dolomite cements that reflect different episodes of cementation. Integration of this information forms the basis for paragenetic interpretations of the dolostones. On Grand Cayman, the Miocene Cayman Formation can be divided into friable, high-porosity dolostones and hard, low-porosity dolostones. Backscatter electron images show that the hard dolostones are characterized by complex arrays of zoned dolomite cements that have occluded most of the pores. Caymanite, an internal sediment, has occluded many of the larger cavities. In contrast, the high-porosity dolostones contain little cement and no internal sediments. Precipitation of the cements and the deposition of internal sediments were related to the passage of large volumes of water through some of the dolostones. Thus, the hard, low-porosity dolostones are found in the 'cap rock' of the formation, in coastal locations, and in areas close to solution-widened fractures. Conversely, the friable, high-porosity dolostones form the lower 'porous unit' of the formation in the interior of the island, where the passage of water was more restricted

Origin of the salt valleys in the Canyonlands section of the Colorado Plateau - Evaporite-dissolution collapse versus tectonic subsidence, 2004, Gutierrez F. ,
The salt valleys over the axis of the salt-cored anticlines in the Paradox fold and fault belt (Canyonlands, Utah and Colorado) are created by subsidence of the anticline crests. Traditionally, the collapse of the anticlinal crests was attributed to dissolution of the salt walls (diapirs) forming the anticline cores. Recent studies based on scaled physical models and field observations propose that the salt valleys are a result of regional extension and that salt dissolution had only a minor influence in the development of the axial depressions. This paper presents several arguments and lines of evidence that refute the tectonic model and support the salt dissolution subsidence interpretation. The development of contractional structures in salt dissolution experiments led the advocates of the tectonic interpretation to reject the dissolution-induced subsidence explanation. However, these salt dissolution models do not reproduce the karstification of salt walls in a realistic way, since their analog involves removal of salt from the base of the diapirs during the experiments. Additionally, numerous field examples and laboratory models conducted by other authors indicate that brittle subsidence in karst settings is commonly controlled by subvertical gravity faults. Field evidence against the regional extension model includes (1) a thick cap rock at the top of the salt walls, (2) the concentration of subsidence deformation structures along the crest of the anticlines (salt walls), (3) deformational structures not consistent with the proposed NNE extension, like crestal synforms and NE-SW grabens, (4) dissolution-induced subsidence structures controlled by ring faulting, revealing deep-seated dissolution, (5) large blocks foundered several hundred meters into the salt wall, (6) evidence of recent and active dissolution subsidence, and (7) the aseismic nature of the recently active collapse faults. Although underground salt dissolution seems to be the main cause for the generation of the salt valleys, this phenomenon may have been favored by regional extension tectonics that enhance the circulation of groundwater and salt dissolution. (C) 2003 Elsevier B.V. All rights reserved

A proposed conceptual model for the genesis of the Derbyshire thermal springs, 2007, Brassington Fc,
Ten thermal springs occur in seven centres in Derbyshire, England, with temperatures up to 27.5 {degrees}C compared with an ambient groundwater temperature of about 9 {degrees}C. The springs discharge from a karstic Dinantian limestone aquifer along the boundary with the overlying Namurian strata around the edge of a regional dome structure. The water is heated by deep circulation to as much as 1 km, with the hottest spring being at Buxton spring, where the water is 5000 years old. A comparison of flow data from the Buxton spring with groundwater hydrographs shows seasonality in the thermal flows, suggesting that the loading effects produced by recharge are transmitted through this deep aquifer system. From a review of the geological history and the hydrogeology and the use of measurements on the Buxton spring it is suggested that the thermal flow system may have its roots in ancient convection cells possibly established in the deeply buried aquifer in late Carboniferous-Early Permian times. Subaerial erosion during the Pliocene removed the impermeable cap rocks and allowed both the thermally heated water to form warm springs and this deep groundwater circulation to be recharged by meteoric waters. The location of the individual springs is likely to date from the downcutting during the Late Pleistocene that formed the modern river valley topography

Potential environmental issues of C02 storage in deep saline aquifers: Geochemical results from the Frio-1 Brine Pilot test, Texas, USA, 2009, Kharaka Y. K. , Thordsena J. , Hovorkab S. D. , Nanceb H. S. , Colee D. R. , Phelps T. J. , Knauss K. G.

Sedimentary basins in general, and deep saline aquifers in particular, are being investigated as possible repositories for large volumes of anthropogenic C02 that must be sequestered to mitigate global wanning and related climate changes. To investigate the potential for the long-term storage of C02 in such aquifers, 1600 t of C02 were injected at 1500 m depth into a 24-m-thick "C" sandstone unit of the Frio Formation, a regional aquifer in the US Gulf Coast Fluid samples obtained before C02 injection from the injection well and an observation well 30 m updip showed a Na-ca-a type brine with ~93,000 mg/L IDS at saturation with CH.t at reservoir conditions; gas analyses showed that CH.t comprised ~95% of dissolved gas, but C02 was low at 0.3%. Following C02 breakthrough, 51 h after injection, samples showed sharp drops in pH (6.5-5.7), pronounced increases in alkalinity (100-3000 mgfL as HC03) and in Fe (30-1100 mgfL), a slug of very high DOC values, and significant shifts in the isotopic compositions of H20, DIC, and CH.t. These data, coupled with geochemical modeling, indicate corrosion of pipe and well casing as well as rapid dissolution of minerals, especially calcite and iron oxyhydroxides, both caused by lowered pH (initially ~3.0 at subsurface conditions) of the brine in contact with supercritical C~. These geochemical parameters, together with perfluorocarbon tracer gases (PFrs), were used to monitor migration of the injected C02 into the overlying Frio "B", composed of a 4-m-thick sandstone and separated from the "C" by ~ts m of shale and siltstone beds. Results obtained from the Frio "B" 6 months after injection gave chemical and isotopic markers that show significant ~ (2.9% compared with 0.3% C02 in dissolved gas) migration into the "B" sandstone. Results of samples collected 15 months after injection, however, are ambiguous, and can be interpreted to show no additional injected C02 in the "B" sandstone. The presence of injected C02 may indicate migration from "C" to "B" through the intervening beds or, more likely, a short-term leakage through the remedial cement around the casing of a 50-year old well. Results obtained to date from four shallow monitoring groundwater wells show no brine or C02 leakage through the Anahuac Formation, the regional cap rock.


Classification of closed depressions in carbonate karst, 2013, Kranjc, A.

Closed depressions are the most characteristic features of karst having dolines among them. Some of the terms, such as doline, uvala, and polje, originate from the Dinaric karst, internationally introduced by J. Cvijic´ in 1893. Karst depressions belong to mezo- and macroforms (from decameter to kilometer scale). The basic feature is the doline, which can be further divided due to its genesis into more main types: solution (the real karst doline), collapse, dropout, buried, cap rock, and suffosion doline. The larger depressions, by dimension and form somewhere between a doline and a polje, are the uvala, but genetically they are closer to the doline. Polje (meaning a plain or field in Slavic languages) is the biggest closed epression, its bottom covering several hundreds of square kilometers. Closed depressions, solution dolines and poljes especially, are regarded as indicators of a fully developed karst (holokarst by Cvijic


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