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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

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That soil water is see soil moisture.?

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Chemistry and Karst, White, William B.
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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Your search for geological record (Keyword) returned 11 results for the whole karstbase:
Seminar on Karst Denudation - Karstic Features in the Geological Record, 1972, Walkden G.

PALUSTRINE CARBONATES AND THE FLORIDA EVERGLADES - TOWARDS AN EXPOSURE INDEX FOR THE FRESH-WATER ENVIRONMENT, 1992, Platt N. H. , Wright V. P. ,
Palustrine carbonates are shallow fresh-water deposits showing evidence of subaqueous deposition and subaerial exposure. These facies are common in the geological record. The intensity of modification is highly variable depending on the climate and the length of emergence. Palustrine limestones have previously been interpreted as marginal lacustrine deposits from fluctuating, low-salinity carbonate lakes, but several problems remain with existing facies models: 1) palustrine carbonates possess a lacustrine biota but commonly display fabrics similar to those of calcretes and peritidal carbonates; 2) the co-occurrence of calcrete horizons and karst-like cavities is somewhat unusual and appears to indicate contemporaneous carbonate precipitation and dissolution in the vadose zone; 3) the dominance of gray colors indicates water-saturation, apparently inconsistent with the evidence for strong desiccation overprint; 4) profundal lake deposits are generally absent from palustrine sequences, and sublittoral facies commonly make up only a small proportion of total thicknesses; 5) no good modem analogue has been identified for the palustrine environment. Analogy with the Florida Everglades suggests a re-interpretation of palustrine limestones, not as pedogenically modified lake margin facies but as the deposits of extensive, very shallow carbonate marshes. The distribution of environments in the Everglades is determined by the local hydrology, reflecting the control of seasonal water-level fluctuations and topography. Climate and topography were the main controls on deposition of ancient palustrine carbonates. As in peritidal sequences, aggradational cycles are capped by a range of lithologies (evaporites, desiccation and microkarst breccias, calcretes, lignite or coal horizons etc.), permitting interpretation of the climate. Careful analysis of lateral facies variations may permit reconstruction of subtle topography. Consideration of the Florida Everglades as a modem analogue for the palustrine environment has suggested the development of an exposure index for fresh-water carbonates

Spatialized morphological analysis: A method of detecting faults, a necessity for hydrodynamic and karstologic studies of cracked aquifers. Examples of the chalky aquifers of Northern France, 1999, Bonnet T, Colbeaux Jp,
Spatialized Morphological Analysis is a new method of detecting faults which uses the morphometric relief data (slope, aspect, elevation) taken from a precise Digital Elevation Model by a computer program. This program, taking the principles of the evolution of relief into account (rock type, climate, chronology), allows the statistical identification of morphometric standards for each type of morphology and the extraction of anomalies to these standards. Some of these anomalies, after a processing of spatial classification, are considered as tectonic tracks. The actual existence of faults, corresponding with anomalies, is verified by classical methods of structural geology. By a better localisation and geometrical definition of faults, this method can allow the optimization of hydrodynamical studies of cracked aquifers, and in case of calcareous ones, a spatial approach to karstification. This method is applied to the north of France chalky aquifer, where, associated with detailed hydrogeological records, it allowed the identification of rapid transfers of groundwater at the level of faults. Even so, exokarstic phenomena are uncommon in this area. Some chemical and textural particularities of Quaternary chalk cover may be the cause of rainwater inhibition, and it is possible that the karstic responses observed are due to considerable mechanical dissolution in the saturated area where tectonic activity (neotectonic faults have been observed) creates environments of preferential flow. (C) Elsevier, Paris

Spectral analysis of a 1000-year stalagmite lamina-thickness record from Shihua Cavern, Beijing, China, and its climatic significance, 1999, Qin Xiaoguang, Tan Ming, Liu Tungsheng, Wang Xianfeng, Li Tieying, Lu Jinpo,
Stalagmite laminae provide a high-resolution geological record of climate change. In this paper, moving spectral analysis is used to analyse a stalagmite lamina thickness record to study climatic variability. It was found that the dominant cycles of the lamina thickness sequence are 2, 3.3, 5-6, 10-12, 14-18, 133 and 194 years. Some of the cycles are the same as the cycles of modern climatic indices, such as the QBO (Quasi Biennial Oscillation) of 2 years, the QTO (Quasi Triple-year Oscillation) cycle of about 3.5 years, the QFO (Quasi Five-year Oscillation) cycle of 5-6 years and the QEO (Quasi Eleven-year Oscillation) cycle of 11 years. It was also found that there are different dominant cycles in different time periods. Usually, the dominant cycles are stronger in wet periods when the microlaminae are thicker. In dry periods, the microlaminae are thinner and the power of the dominant cycles is also weaker. Another feature is that the power of the dominant cycles and their long-term periods and frequencies appear to change. These phenomena are important for understanding the climatic changes in Beijing area over the last 1 ka

Carbonate platform systems: components and interactions -- an introduction, 2000, Insalaco Enzo, Skelton Peter, Palmer Tim J. ,
Carbonate platforms are open systems with natural boundaries in space and time. Across their spatial boundaries there are fluxes of energy (e.g. light, chemical energy in compounds, and kinetic energy in currents and mass flows) and matter (e.g. nutrients, dissolved gases such as CO2, and sediment -- especially, of course, carbonates). Internally, these fluxes are regulated by myriads of interactions and feedbacks (Masse 1995), and the residue is consigned to the geological record. The most distinctive aspect of carbonate platforms is the predominant role of organisms in producing, processing and/or trapping carbonate sediment, even in Precambrian examples. Because of evolutionary changes in this strong biotic input, it is harder to generalize about carbonate platforms than about most other sedimentary systems. Evolution has altered both the constructive and destructive effects of platform-dwelling organisms on carbonate fabrics, with profound consequences for facies development. Moreover, changing patterns in the provision of accommodation space (e.g. between greenhouse and icehouse climatic regimes) have also left their stamp on facies geometries, in turn feeding back to the evolution of the platform biotas. Hence simplistic analogies between modern and ancient platforms may give rise to misleading interpretations of what the latter were like and how they formed. Although a number of carbonate platform and reef specialists have warned of the dangers of such misplaced uniformitarianism (e.g. Braithwaite 1973; Gili et al. 1995; Wood 1999), it remains depressingly commonplace in the literature on ancient carbonate platforms. The endless quest in the literature for an allpurpose definition of reefs' ... This 250-word extract was created in the absence of an abstract

Palaeo-mixing zone karst features from Palaeocene carbonates of north Spain: criteria for recognizing a potentially widespread but rarely documented diagenetic system, 2001, Bacetaa J. I. , Wrightb V. P. , Pujalte V.

Marine-meteoric mixing zone dissolution effects are a major feature of present day karst systems in carbonate platforms,yet are rarely reported in the geological record. An example is described from the upper Danian platform limestones of the Alava province,in  the western Pyrenees,north Spain. This consists of several narrow zones with sponge-like porosity analogous to the "Swiss-cheese" features found in present day mixing  zones. These zones are stained by Fe-oxides and overlie limestones which are irregularly  dolomitized  and contain disseminated pyrite. These high-porosity  zones are interpreted as having developed in marine mixing zones where mixing corrosion and microbially  mediated processes increased dissolution. If collapsed,ancient mixing zones could be misinterpreted as "terra-rossa" palaeosols. The main criteria to identify them as mixing zone products are their occurrence below a palaeo-meteoric phreatic zone,their association with stratified oxic and anoxic redox zones and petrographic evidence for highly variable calcite saturation states.


Palaeo-mixing zone karst features from Palaeocene carbonates of north Spain: criteria for recognizing a potentially widespread but rarely documented diagenetic system , 2001, Baceta J. I. , Wrightb V. P. , Pujaltec V.

Marine-meteoric mixing zone dissolution effects are a major feature of present day karst systems in carbonate platforms,yet are rarely reported in the geological record. An example is described from the upper Danian platform limestones of the Alava province,in the western Pyrenees,north Spain. This consists of several narrow zones with sponge-like porosity analogous to the "Swiss-cheese" features found in present day mixing zones. These zones are stained by Fe-oxides and overlie limestones which are irregularly dolomitized and contain disseminated pyrite. These high-porosity zones are interpreted as having developed in marine mixing zones where mixing corrosion and microbially mediated processes increased dissolution. If collapsed,ancient mixing zones could be misinterpreted as "terra-rossa" palaeosols. The main criteria to identify them as mixing zone products are their occurrence below a palaeo-meteoric phreatic zone,their association with stratified oxic and anoxic redox zones and petrographic evidence for highly variable calcite saturation states


Paleocollapse structures as geological record for reconstruction of past karst processes during the upper miocene of Mallorca Island, 2004, Robledo Ardila P. A. , Durn J. J. , Pomar L.
Paleocollapse structures and collapse breccias are one of the major features for paleokarst analysis and paleoclimate record. These are affecting the Llucmajor and Santany carbonate platforms. These platforms, of southern and eastern Mallorca respectively, are a good example of progradation reef platform in the western Mediterranean. The Santany platform is constituted of two sedimentary units, both affected by paleocollapse structures: (1) The Reef Complex attributed to the upper Tortonian-lower Messinian; (2) Santany Limestone attributed to the Messinian. There are abundant paleocollapse outcropping in the Reef Complex and Santany Limestone units. These structures have been produced by roof collapse of caverns developed in the underlying reefal complex. According to the genetic model, the origin of same paleocollapse structures may be related to early diagenetic processes controlled by high-frequency sea-level fluctuations. During the lowstands of sea level, fresh water flow or mixing zone might have created a cave system near the water table by dissolution of aragonite in the reef front facies and coral patches existing in the lagoonal beds. During subsequent rise and highstands of sea level, inner-shelf beds overlaid the previously karstified reef-core and outer-lagoonal beds. Increase of loading by subsequent accretion of the shallow-water carbonate might have produced paleocollapse structures by gravitational collapse of cave roof. Morphometric and structural classification of paleocollapse is based on geometric and structural criteria according to the type of deformed strata and strata dip. Paleocollapse structures can be classified according to geometric section, size of the paleocave and lithification degree of the host rock when collapsed. Breccias are classified as crackle, mosaic and chaotic types. In same paleocollapse the type of breccias present a vertical and lateral gradation, from crackle in the upper part, to chaotic in the lower part of the paleocollapse. Chaotic breccias grade from matrix-free, clasts-supported breccias to matrix-supported breccias. Relationship with high frequency of sea-level fluctuation, facies architecture, classification features and products permit to enhance a general paleoclimatic framework.

Giant pockmarks in a carbonate platform (Maldives, Indian Ocean), 2011, Betzler C. , Lindhorst S. , Hubscher C. , Ludmann T. , Furstenau J. , Reijmer J.

Circular structures and depressions in carbonate platforms are known to represent karst chimneys or sinkholes which form as a response to rock solution. This formation mechanism is plausible for shallow-water carbonates which lie in the reach of meteoric diagenesis or fresh-water lenses. Circular structures which occur in deeper waters, however, need an alternative interpretation. Such an example of sea-floor depressions in more than 300. m deep waters occurs in the Inner Sea of the Maldives carbonate platform in the Indian Ocean. The structures were mapped with multibeam and Parasound, multi-channel seismics were used to link the depressions with structures at depth. The circular depressions have diameters of up to 3000. m and depths of up to 180. m. The craters are interpreted as pockmarks formed through the venting of gas and fluids. Gas and fluid lenses below the pockmarks are reflected by bright spots in the seismic sections as well as a reduction of the instantaneous frequency. These areas at depth are linked to chimneys connected to faults and drowned Oligocene carbonate banks. A model is presented that relates the different forms and sizes of the structures to distinct development stages of sea floor deformation to one process. Early stages of gas and fluid migration into the shallow part of the sedimentary succession induce formation of dome-shaped bodies. Initial gas and fluid escape to the sea floor is reflected by the formation of sand volcanoes and aligned small pockmarks. Active pockmarks are the deepest, and have the shape of truncated cones in cross section. Mature pockmarks are characterized by erosion of the flanks of the structure by bottom currents. Late stage pockmarks are bowl-shaped in cross section, and are to different degrees filled by drift sediments. Packages of strata revealing high reflection amplitudes and high interval velocities interpreted as microbially-mediated carbonate precipitates underlie some of the pockmarks. The pockmarks in the Maldives show that circular structures other than solution-related features can be abundant in carbonate platform deposits and that such structures may be more abundant in the geological record of carbonate platforms as previously thought. Pockmarks in the Maldives indicate that the archipelago is an example of a hydrocarbon system which consists of an isolated oceanic carbonate platform overlying a volcanic basement and lacustrine source rocks.


A geomorphological and speleological approach in the study of hydrogeology of gypsum karst of Sorbas (SE Spain), 2012, Sanna L, Gazquez F. , Calaforra J. M.

The Sorbas massif (Almeria, SE Spain) is one of most karstified gypsiferous areas of the world, with hundreds of dolines and different karst features. In this massif more than 1000 caves have been discovered in an area of about 12 km2. Its Messinian gypsum, deposited in a Neogene intramontane basin, is composed of continuous strata of very pure selenite. The purpose of this research is to identify the main karst geomorphological features and to integrate these data with hydrogeological records for better understanding the role of the karst aquifer in the groundwater recharge of the Aguas River. This study took place in the southern part of the Sorbas gypsum plateau with several steps and multiple field campaigns for geomorphological and geostructural data compilation and to record the different karst forms. Also water samples from the main springs have been collected for geochemical analysis. All field items have been inventoried with corresponding spatial position and compared with the previously existing information. Subsequently, an exhaustive data elaboration was performed leading to the definition of the karst features of the area, rendered by maps. To assess the extent of karstification, the spatial analysis of the cave entrance’s distribution together with structural alignments have been studied.
The cave entrances, a means of access to deep karst, are an expression of discontinuous surface karst phenomenon closely connected with underground drainage that allow to reconstruct the main direction of groundwater flow. This kind of approach can be apply in those areas where rock is exploited, to discern a possible indicator of the effects of the mining and to find the best management conditions that allow the conservation of most of the cavities, the preservation of the recharge basin of the karst system and springs, the minimum affectation to the vadose groundwater flow, the protection of nearby springs and minimizing the visual impact.


Karstification of Dolomitic Hills at south of Coimbra (western-central Portugal) - Depositional facies and stratigraphic controls of the (palaeo)karst affecting the Coimbra Group (Lower Jurassic), 2014, Dimuccio, Luca Antonio

An evolutionary model is proposed to explain the spatio-temporal distribution of karstification affecting the Lower Jurassic shallow-marine carbonate succession (Coimbra Group) of the Lusitanian Basin, cropping out in the Coimbra-Penela region (western-central Portugal), in a specific morphostructural setting (Dolomitic Hills). Indeed, in the Coimbra Group, despite the local lateral and vertical distributions of dolomitic character and the presence of few thick sandy-argillaceous/shale and marly interbeds, some (meso)karstification was identified, including several microkarstification features. All types of karst forms are commonly filled by autochthonous and/or allochthonous post-Jurassic siliciclastics, implying a palaeokarstic nature.

The main aim of this work is to infer the interplay between depositional facies, diagenesis, syn- and postdepositional discontinuities and the spatio-temporal distribution of palaeokarst. Here, the palaeokarst concept is not limited to the definition of a landform and/or possibly to an associated deposit (both resulting from one or more processes/mechanisms), but is considered as part of the local and regional geological record.

Detailed field information from 21 stratigraphic sections (among several dozens of other observations) and from structural-geology and geomorphological surveys, was mapped and recorded on graphic logs showing the lithological succession, including sedimentological, palaeontological and structural data. Facies determination was based on field observations of textures and sedimentary structures and laboratory petrographic analysis of thin-sections. The karst and palaeokarst forms (both superficial and underground) were classified and judged on the basis of present-day geographic location, morphology, associated discontinuities, stratigraphic position and degree of burial by post-Jurassic siliciclastics that allowed to distinguish a exposed karst (denuded or completely exhumed) than a palaeokarst (covered or partially buried).

A formal lithostratigrafic framework was proposed for the local ca. 110-m-thick combined successions of Coimbra Group, ranging in age from the early Sinemurian to the early Pliensbachian and recorded in two distinct subunits: the Coimbra formation, essentially dolomitic; and the overlying S. Miguel formation, essentially dolomitic-limestone and marly-limestone.

The 15 identified facies were subsequently grouped into 4 genetically related facies associations indicative of sedimentation within supra/intertidal, shallow partially restricted subtidal-lagoonal, shoal and more open-marine (sub)environments - in the context of depositional systems of a tidal flat and a very shallow, inner part of a low-gradient, carbonate ramp. In some cases, thick bedded breccia bodies (tempestites/sismites) are associated to synsedimentary deformation structures (slumps, sliding to the W to NW), showing the important activity of N–S and NNE–SSW faults, during the Sinemurian. All these deposits are arranged into metre-scale, mostly shallowing-upward cycles, in some cases truncated by subaerial exposure events. However, no evidence of mature pedogenetic alteration, or the development of distinct soil horizons, was observed. These facts reflect very short-term subaerial exposure intervals (intermittent/ephemeral), in a semiarid palaeoclimatic setting but with an increase in the humidity conditions during the eogenetic stage of the Coimbra Group, which may have promoted the development of micropalaeokarstic dissolution (eogenetic karst).

Two types of dolomitization are recognized: one (a) syndepositional (or early diagenetic), massive-stratiform, of “penesaline type”, possibly resulting from refluxing brines (shallow-subtidal), with a primary dolomite related to the evaporation of seawater, under semiarid conditions (supra/intertidal) and the concurrent action of microbial activity; another (b) later, localized, common during diagenesis (sometimes with dedolomitization), particularly where fluids followed discontinuities such as joints, faults, bedding planes and, in some cases, pre-existing palaeokarstic features.

The very specific stratigraphic position of the (palaeo)karst features is understood as a consequence of high facies/microfacies heterogeneities and contrasts in porosity (both depositional and its early diagenetic modifications), providing efficient hydraulic circulation through the development of meso- and macropermeability contributed by syn- and postdepositional discontinuities such as bedding planes, joints and faults. These hydraulic connections significantly influenced and controlled the earliest karst-forming processes (inception), as well as the degree of subsequent karstification during the mesogenetic/telogenetic stages of the Coimbra Group. Multiple and complex karstification (polyphase and polygenic) were recognized, including 8 main phases, to local scale, integrated in 4 periods, to regional scale: Jurassic, Lower Cretaceous, pre-Pliocene and Pliocene-Quaternary. Each phase of karstification comprise a specific type of (palaeo)karst (eogenetic, subjacent, denuded, mantled-buried and exhumed).

Finally, geological, geomorphological and hydrogeological characteristics allowed to describe the local aquifer. The elaborated map of intrinsic vulnerability shows a karst/fissured and partially buried aquifer (palaeokarst) with high to very high susceptibility to the contamination.


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