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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 arthropods is animals with jointed legs and bard external skeletons (exoskeletons). the group includes insects, crustaceans, spiders, millipedes, and several other types of animals commonly found in caves [23].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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 trends (Keyword) returned 117 results for the whole karstbase:
Showing 106 to 117 of 117
Assessing copepod (Crustacea: Copepoda) species richness at different spatial scales in northwestern Romanian caves, 2011, Ioana N. Meleg, Frank Fiers, Oana Moldovan

The aim of the present study was to assess copepod species richness in groundwater habitats from the Pădurea Craiului Mountains, Transylvania (northwestern Romania). Five species richness estimators (one asymptotic, based on species accumulation curves, and four non-parametric) were compared by testing their performances in estimating copepod species richness at three hierarchical spatial scales: cave, hydrographic basin, and karstic massif. Both epigean and hypogean species were taken in account. Two data sets were used in computing copepod species richness: 1. samples collected continuously during one year (dripping water) and seven months (pools) from five caves, and 2. samples collected from pools in twelve additional caves (data gathered from literature). Differences in copepod species richness among caves and hydrographic basins suggest that local environmental features are important in determining local species richness trends.


Identifying the link between lineament and cave passage trends to comprehend fractures continuity and influence on the Kinta Valley karst system, 2012, Kassa Solomon, Pierson Bernard, Chow Weng S. , Talib Jasmi B. Ab. .

The Kinta Valley karst landscape is characterised by residual limestone hills scattered all over the valley. The aim of this study is to ascertain the link between lineament and cave passage orientations, and to identify the main fracture controlling the karst features. To achieve that, standard cave surveying and direct lineament extraction techniques, from a 2.5m resolution spot image, were employed. Six trends of lineaments were obtained from the remnant limestone hills, and their main orientation appears to be in the NNW-SSE. Similarly, various caves were surveyed and mapped; their passage orientation analyses reveal that NNW-SSE is the prominent direction. The similarity of the lineaments orientation and caves passage trend attests that the karst formation is controlled by the geological structures. Such a similar trend observed in all hills enabled to infer the orientation of the primary structure responsible for the formation of the extant karst features. The multi-fracturing episodes rendered the Kinta Valley to be structurally complex and the karst features unravelled this effect, as evidenced by features such as circular and sinuous cave passage morphology, which developed ensuing fractures oriented in different directions.


Regionalization Based on water Chemistry and Physicochemical Traits in the Ring of Cenotes, Yucatan, Mexico, 2012, Prezceballos R. , Pachecovila J. , Eunvila J. I. , Hernndezarana H.

 

Assessing water quality in aquifers has become increasingly important as water demand and pollution concerns rise. In the Yucatan Peninsula, sinkholes, locally known as cenotes, are karst formations that intercept the water table. Cenotes are distributed across the peninsula, but are particularly dense and aligned along a semicircular formation called the Ring of Cenotes. This area exhibits particular hydrogeological properties because it concentrates, channels, and discharges fresh water toward the coasts. In this study, we identify spatial and temporal variations in chemical and physical variables at twenty-two cenotes to identify groups that share similar characteristics. Water samples from each cenotes were taken at three depths (0.5, 5.5, and 10.5 m) and during three seasons (dry, rainy, and cold-fronts season). Field measurements of pH, temperature, electrical conductivity, and dissolved oxygen were taken, and the concentrations of major ions (K+, Na+, Mg2+, Ca2+, HCO{ 3 , SO2{ 4 , Cl2 and NO{ 3 ) were quantified. Identifying regions of the cenotes were done by applying multivariate statistical techniques (PCA, PERMANOVA, CAP). The chemical variables revealed spatial trends among the cenotes. We identified three main regions. Region 1 is associated with sea-water encroachment and high levels of sulfate that travel through preferential groundwater flowpaths from evaporites in the southern Yucatan Peninsula; Region 2 is a recharge zone, and Region 3 is characterized by sea water encroachment and by the high chemical and physical variability associated with groundwater flow from the east.


Alteration of isotopic composition of wallrock of hypogene karst conduits in the Crimean Piedmont, 2013, Dublyansky Y. V. , Klimchouk A. B. , Tymokhina E. I. , Amelichev G. N. , Sptl C.

The paper presents the results of a systematic study of the oxygen and carbon isotopes in the walls of the hypogene karst conduits in the Crimean Piedmont, including conduits that are entirely open and represent the cuesta cliffs. Most of the studied cores reveal wide zones of weak isotopic alteration (tens of cm to several m; 1 to 3 ‰) and narrow zones of strong alteration (4 to 15 mm; up to 4-7 ‰) for both C and O. Interaction between carbonate bedrock and fluids is expected in relatively closed hydrogeological conditions characteristic of the hypogene speleogenesis. The most-altered rock has isotopic composition identical to that of the phreatic speleothems, found in some of the studied conduits. This suggests that the altering waters and mineral forming solutions are genetically related. Several alteration trends are apparent in the C-O isotope space, suggesting that the bedrock has experienced more than one stage of alteration, characterized by different physico-chemical parameters of fluids (including different sources and isotopic composition of carbon and, possibly, different temperatures).


THE USE OF DROUGHT-INDUCED “CROP LINES” AS A TOOL FOR CHARACTERIZATION OF KARST TERRAIN, 2013, Panno S. V. , Luman D. E. , Kelly W. R. , Alschuler M. B.

The persistent drought of the 2012 summer in the Midwestern United States significantly impacted the health and vigor of Illinois’ crops. An unforeseen outcome of the extreme drought was that it provided a rare opportunity to examine and characterize the bedrock surface and underlying karst aquifer within the Driftless Area of northwestern Illinois. Complex networks of vegetated lines and polygonal patterns, herein referred to as crop lines, crisscrossed the dry summer landscape of Jo Daviess County. Initially, the crop lines were examined and photographed using a handheld digital camera on the ground and from a small aircraft at 300 meters altitude above ground level (AGL). The orientations, widths and horizontal separations of the lines were measured. Crop lines and their patterns and orientations were compared with those of crevices in outcrops, road cuts and quarries, and with lineaments seen in LiDAR elevation data of Jo Daviess County.
Primarily confined to alfalfa fields and, to a lesser extent, soybeans and corn, the crop lines are the result of a combination of extremely dry conditions, and a thin soil zone overlying fractured and creviced Galena Dolomite bedrock. The plants forming the lines tend to grow denser, taller (0.5 m vs 0.15 m) and darker/greener than those in adjacent areas. Alfalfa taproots are the deepest of the aforementioned crops extending up to 7 m below the surface. Groundwater and associated soil moisture within the vadose zone present within bedrock fractures and crevices provide the necessary moisture to sustain the overlying healthy plants, while the remaining area of the field exhibits stunted and sparse plant growth. Overall, the crop lines are a reflection of the creviced pattern of the underlying karst bedrock and associated karst aquifer, and reveal the degree and extent of karstification in eastern Jo Daviess County. The crop lines were consistent with the angular lines of adjacent streams that show a rectangular drainage pattern. Stream patterns like these are well known and are due to drainage controlled by crevice/fracture patterns in the top of bedrock. The lines appear to have been formed by two sets of fractures trending roughly north-south and east-west with occasional cross-cutting fractures/crevices. The east-west trending lines are consistent with tension joints, and the north-south lines are consistent with the shear joints identified by earlier researchers. The trends of the crop lines, tension and shear joints are similar to those of lineaments identified from LiDAR elevation data in the same area (N 20° W, and N 70° W and N 70° E) and coincide with the occurrence of karst features throughout eastern Jo Daviess County.The pattern observed in the crop lines closely mimics the fracture/crevice patterns of the bedrock surface. The widths and extent of the lines may be used as a surrogate for the karst features present on the bedrock surfaces. Crop lines, coupled with solution-enlarged crevices seen in bedrock exposures, yield a three dimensional view of the bedrock crevice-fracture system, and ultimately could provide a more complete and accurate model of the karst aquifer in the study area and similar karst areas in the Midwestern United States and perhaps in other karst regions of the world.


LANDFORMS OF MOUNTAINOUS KARST IN THE MIDDLE LATITUDES: REFLECTIONS, TRENDSAND RESEARCH PROBLEMS, 2013, Sauro Ugo

Radon, carbon dioxide and fault displacements in central Europe related to the Tohoku Earthquake, 2014, Briestensky Milos, Thinova Lenka, Praksova Renata, Stemberk Josef, Rowberry Matt D. , Knejflova Zuzana

Tectonic instability may be measured directly using extensometers installed across active faults or it may be indicated by anomalous natural gas concentrations in the vicinity of active faults. This paper presents the results of fault displacement monitoring at two sites in the Bohemian Massif and Western Carpathians. These data have been supplemented by radon monitoring in Mladec Caves and by carbon dioxide monitoring in Zbrasov Aragonite Caves. A significant period of tectonic instability is indicated by changes in the fault displacement trends and by anomalous radon and carbon dioxide concentrations. This was recorded around the time of the catastrophic MW = 9.0 Tohoku Earthquake which hit eastern Japan on 11 March 2011. It is tentatively suggested that the Tohoku Earthquake in the Pacific Ocean and the unusual geodynamic activity recorded in the Bohemian Massif and Western Carpathians both reflect contemporaneous global tectonic changes.


Geologic constraints and speleogenesis of Cova des Pas de Vallgornera, a complex coastal cave from Mallorca Island (Western Mediterranean), 2014, Ginés J. , Fornós J. J. , Ginés A. , Merino A. , Gràcia F.

The flat areas of eastern and southern Mallorca host a remarkable coastal karst, where Cova des Pas de Vallgornera stands out due to its length (more than 74 km) and its special morphological suite. The pattern of the cave is quite heterogeneous showing sharp differences produced by the architecture of the Upper Miocene reef: spongework mazes and collapse chambers dominate in the reef front facies, whereas joint-guided conduits are the rule in the back reef carbonates. Regarding the speleogenesis of the system, a complex situation is envisaged involving three main agents: coastal mixing dissolution, drainage of meteoric diffuse recharge, and hypogene basal recharge related to local geothermal phenomena. The cave system is disposed in two main tiers of passages, of which geomorphologic interpretations are derived from their elevation data. The evolutionary trends as well as the chronology of the different cave sections are difficult to establish owing to the frequent shifting of the coastal base level during the Plio-Quaternary. In this respect, the genesis and evolution of the cave were fully controlled by sea-level fluctuations in the Western Mediterranean basin, with the main phases of cave formation, based on vertebrate paleontological data, going back to mid-Pliocene times.


The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , 2014, Briestensky Milos, Stemberk Josef, Rowberry Matt D. ,

The EU-TecNet fault displacement monitoring network records three-dimensional displacements across specifically selected tectonic structures within the crystalline basement of central Europe. This paper presents a study of recent and active tectonics at Západní Cave in northern Bohemia (Czech Republic). It extends previous geological research by measuring speleothem damage in the cave and monitoring displacements across two fault structures situated within the Lusatian Thrust Zone. The speleothem damage reflects strike-slip displacement trends: the WSW-ENE striking fault is associated with dextral strike-slip displacement while the NNW-SSE striking fault is associated with sinistral strike-slip displacement. These measurements demonstrate that the compressive stress σ1 is located in the NW or SE quadrant while the tensile stress σ3 is oriented perpendicular to σ1, i.e. in the NE or SW quadrant. The in situ fault displacement monitoring has confirmed that movements along the WSW-ENE striking fault reflect dextral strike-slip while movements along the NNW-SSE striking fault reflect sinistral strike-slip. In addition, however, monitoring across the NNW-SSE striking fault has demonstrated relative vertical uplift of the eastern block and, therefore, this fault is characterised by oblique movement trends. The fault displacement monitoring has also shown notable periods of increased geodynamic activity, referred to as pressure pulses, in 2008, 2010-2011, and 2012. The fact that the measured speleothem damage and the results of fault displacement monitoring correspond closely confirms the notion that, at this site, the compressive stress σ1 persists in the NW or SE quadrant. The presented results offer an insight into the periodicity of pressure pulses, demonstrate the need for protracted monitoring periods in order to better understanding geodynamic processes, and show that it is possible to characterise the displacements that occur across individual faults in a way that cannot be accomplished from geodetic measurements obtained by Global Navigation Satellite Systems.


The hydrogeology of high-mountain carbonate areas: an example of some Alpine systems in southern Piedmont (Italy), 2015,

The hydrogeological characteristics of some springs supplied by high-mountain carbonate rock aquifers, located in the south of Piedmont, in Italy, are presented in this work. The aquifers have different geological-structural conditions, including both deep and superficial karstification. Their catchment areas are located in a typical Alpine context at a high altitude of about 2000 m. These aquifers are ideal representations of the different hydrogeological situations that can be encountered in the high-altitude carbonate aquifers of the Mediterranean basin. It is first shown how the high-altitude zones present typical situations, in particular related to the climate, which control the infiltration processes to a great extent. Snowfall accumulates on the ground from November to April, often reaching remarkable thicknesses. The snow usually begins to melt in spring and continues to feed the aquifer for several months. This type of recharge is characterized by continuous daily variations caused by the typical thermal excursions. The hourly values are somewhat modest, but snowmelt lasts for a long time, beginning in the lower sectors and ending, after various months, in the higher areas. Abundant rainfall also occurs in the same period, and this contributes further to the aquifer supply. In the summer period, there is very little rainfall, but frequent storms. In autumn, abundant rainfall occurs and there are there fore short but relevant recharge events. It has been shown how the trend of the yearly flow of the high mountain springs is influenced to a great extent by the snowmelt processes and autumn rainfall. It has also been shown, by means of the annual hydrographs of the flow and the electric conductivity of the spring water, how the different examined aquifers are characterized by very different measured value trends, according to the characteristics of the aquifer.

 


Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), 2015, Briestensky Milos, Rowberry Matt, Stemberk Josef, Stefanov Petar, Vozar Jozef, Sebela Stanka, Petro Lubomir, Bella Pavel, Gaal Ludovit, Ormukov Cholponbek,

The EU-TecNet monitoring network uses customised three-dimensional extensometers to record transient deformations across individual faults. This paper presents the first results from two newly established monitoring points in the Balkan Mountains in Bulgaria. The data from Saeva Dupka, recorded across an EEN-WWS striking fault, show sinistral strike-slip along the fault and subsidence of the southern block. Much of the subsidence occurred around the time of the distal MW = 5.6 Pernik Earthquake. An important transient deformation event, which began in autumn 2012, was reflected by significant compression and subsequent extension across the monitored fault. The data from Bacho Kiro, recorded across a NE-SW striking fault, show sinistral strike-slip along the fault and subsidence of the northwestern block. The same important deformation event was reflected by changes in the strike-slip, dip-slip, and horizontal opening/closing trends. These results have been compared to data from other monitoring points in the Western Carpathians, External Dinarides, and Tian Shan. Many of the sites evidence simultaneous displacement anomalies and this observation is interpreted to reflect the widespread propagation of a tectonic pressure pulse towards the end of 2012.


The karst paradigm: changes, trends and perspectives, 2015, Klimchouk, Alexander

The paper examines representative definitions of karst (21), and discusses some concepts that influenced the modern un­derstanding of the phenomenon. Several trends are discussed that took karst science beyond the limits of the traditional par­adigm of karst. Dramatic progress in studies of speleogenesis plays the most significant role in changes taking place in the general understanding of karst. Also important is an adoption of the broad perspective to karst evolution which goes beyond the contemporary geomorphologic epoch and encompasses the entire life of a geological formation. Speleogenesis is viewed as a dynamic hydrogeological process of self-organization of the permeability structure in soluble rocks, a mechanism of the specific evolution of the groundwater flow system. The result is that these systems acquire a new, "karstic", quality and more complex organization. Since almost all essential attributes of karst owe their origin to speleogenesis, the latter is considered as the primary mechanism of the formation of karst. Two fundamental types of speleogenesis, hypogene and epigene, differentiate mainly due to distinct hydrodynamic characteristics of the respective groundwater flow systems: (1) of layered aquifer systems and fracture-vein flow systems of varying depths and degrees of confinement, and (2) of hydrodynamically open, near-surface unconfined systems. Accordingly, two major genetic types of karst are distinguished: hypogene and epigene. They differ in many characteristics, notably in relationships with the surface, hydrogeological behaviour, groundwater quality, and the areas of practical importance and approaches to solving karst-related issues. Although views on essential attributes of karst have been clearly changing, this was not reflected in definitions of the notion which are in broad use in the earth-science literature. A refined approach is suggested to the notion of karst in which it is viewed as a groundwater (fluid) flow system of a specific kind, which has acquired its peculiar properties in the course of speleogenesis.


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