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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. ...

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That overburden pressure is the pressure exerted by weight of the overburden column [16].?

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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 transform (Keyword) returned 94 results for the whole karstbase:
Showing 76 to 90 of 94
Unique iron-manganese colonies of microorganisms in Zoloushka Cave (Ukraine-Moldova), 2009, Andreychouk V. N. , Klimchouk A. , Boston P. , Galuskin E.

During open-pit quarrying and related lowering of groundwater level in the gypsum karst aquifer (since 1950), large cave Zoloushka became accessible for direct exploration, in which considerable geochemical transformations of environment occurred, accompanied by the formation of specific deposits, as well as by burst of microbial activity. Among microorganisms, some of the most active were various iron bacteria. Microbial activity has resulted in precipitation of black and red biochemical formations – microbialites (coatings, crusts, films, stalactites, stalagmites, etc.), which cover walls and floors of cave passages. Most interesting among the microbialites are iron-rich colonial formations of various shapes (stalagmite-like, tube-like, coral-like, etc.) formed by yet unidentified fungi-like microorganisms which likely are new to science. In this paper, we characterize occurrence and morphology of the colonial aggregates, morphology and chemical composition of microorganisms  and develop working hypotheses of their identification.


TIME SERIES ANALYSIS, MODELLING AND ASSESSMENT OF OPTIMAL EXPLOITATION OF THE NEMANJA KARST SPRINGS, SERBIA, 2010, Jemcov I. , Petri? M.
The time series analysis was applied in the case-study of a karst aquifer in Serbia in order to study its functioning, hydrodynamic behavior and hydraulic properties. Focusing on the definition of groundwater budget, due to very complex functioning of karst systems the correlation and spectral analyses were used to emphasize the importance of transforming the input data precipitation to effective infiltration. Thee characterization of karst aquifer was further improved by separating the output component discharge to base flow and flatfoot components. Additionally, the importance of these transformations was proved in application of the regression model for the simulation of discharges based on the effective infiltration functions. A recharge-discharge model was applied in accordance with the active groundwater management, defining optimal exploitable regimes, which included the analyses of storage changes in karst water reservoirs under natural conditions, and calculation of the potential exploitation conditions.

Stages in hypergene transformation of sulfate-carbonate sequences (on example of breakdown piles of organ pipes of Kungur Ice Cave), 2010, Kadebskaya O. , Tchaikovskiy I.

The article reveals the influence of microclimate on the composition of deposits in Kungur Ice cave. Deposits of breakdown piles under “organ pipes” in different climatic zones were investigated. It was established that the material of breakdown piles of identical initial composition has different ways of transformation related to microclimate. In the cold zone negative temperatures “freeze” transformation processes of calcium and sulfate materials. The main process of mineral formation in this zone is cryogenic mineralization of sulfate and calcium water. The transitional zone (with temperatures between 0°C and 3°C) is distinguished by the presence of authigenic calcium breccias and various gypsum forms in breakdown piles. In the warm zone complete dissolution of gypsum and partial dissolution of carbonate debris occurs. Studying deposits bearing climatic markers can be used for identifying dominant paleoclimatic conditions in the cave.


Evolutionary typology of karst, 2010, Klimchouk A. B.

The paper reveals the hydrogeological essence of karst, provides its definition, substantiates the evolutionary approach to karst typology and offers a respective classification. The evolutional typology of is based on consideration of geological evolution of a body of karstified rocks (unit, formation) and evolution of a groundwater circulation system. It reflects such basic  regularities of geological evolution as directed development and cyclicity. Different stages of post-sedimentary transformation of rocks and of the development of a geohydrodynamic systems are characterized by certain steady combinations of lithologic and structural pre-requisites for groundwater flow and speleogenesis, the mode of groundwater flow, recharge and discharge conditions, thermobaric and geohydrochemical conditions. Such combinations result in formation of karst systems with certain characteristic properties – i.e. types of karst. The directed development – results in regular changes of karst types. Changes of one type of karst into another is conditioned by the processes of tectonic and geomorphological evolution, which determine change of border conditions for groundwater flow and speleogenesis.

Within the framework of the proposed classification, the types of karst correspond to the successive stages of its evolution, between which boundary conditions of groundwater flow and speleogenesis, external factors and internal mechanisms of karstification (speleogenesis) differ considerably and in a regular manner.  The evolutional types of karst integrally characterize the most substantial properties of karst systems (structure of secondary porosity and permeability, degree and character of karst manifestation in surface relief, hydrogeologic features, potential for collapse and subsidence hazard, etc.), speleogenetic environments and dominant mechanisms, as well as potential of inheritance of porosity and permeability structures from the previous stages of development. This allows using this classification for resolving of broad range of scientific and practical problems, related to karst.


The role of geochemical transformations in karst geomorphogenesis, 2010, Vakhrushev B. A.

Geochemical transformations in the system «water - rock» constitute the genetic basis of karst morphogesis. The article demonstrates that corrosion and chemical sedimentation are largely responsible for the morphological look of cavities. The basic method used is thermodynamic calculations of geochemical equilibria, which determine an aggressiveness of natural solutions.

The change of isobar-isothermal potential (free energy of Gibbs) was used as a measure of chemical affinity of matters, i.e. their capabilities to enter into a reaction between them with formation of other matters.

Variety of hydrochemical situations taking place in carbonate , summarized in five typical conditions, which include considerable part of possible karst morphogenetic settings, while others can be obtained by combination of the examined ones. Every situation is described by hydrochemical calculations.

The second part of the paper is dedicated to practical application of the described methodology, i.e. to the calculations of thermodynamic equilibria observed in the underground streams of the Krasnaya (Red) Cave in Crimea. Close connection of morphological look of the cave with geochemical transformations is shown, which control corrosion and chemical accumulation along the whole length of the karst system.


Tracing the sources of cave sulfates: a unique case from Cerna Valley, Romania, 2011, Onac Bogdan P. , Wynn Jonathan G. , Sumrall Jonathan B.

In order to reliably distinguish between different genetic processes of cave sulfate formation and to quantify the role of thermo-mineral waters on mineral deposition and cave morphology, it is critical to understand sulfur (S) sources and S transformations during hydrological and speleogenetic processes. Previous work has shown that sulfuric acid speleogenesis (SAS) often produces sulfate deposits with 34S-depleted isotopic signatures compared to those of the original source of S in sulfate rocks. However, 34S-depleted isotopic composition of S-bearing minerals alone does not provide enough information to clearly distinguish SAS from other speleogenetic processes driven by carbonic acid, geothermal heat, or other processes. The isotopic composition (δ18O and δ34S) of sulfate minerals (mainly gypsum) from seven caves of the Cerna Valley (Romania) defines three distinct populations, and demonstrates that the δ34S values of SAS-precipitated cave sulfates depend not only on the source of the S, but also on the H2S:SO4 2− ratio during aqueous S species reactions and mineral precipitation. Population 1 includes sulfates that are characterized by relatively low δ34S values (−19.4 to −27.9‰) with δ18O values between 0.2 and 4.3‰ that are consistent with oxidation of dissolved sulfide produced during methane-limited thermochemical sulfate reduction (TSR) that presently characterizes the chemistry of springs in the upper Cerna Valley. Population 2 of cave sulfates has 34S enriched δ34S values (14.3 to 19.4‰) and more 18O-depleted δ18O values (from −1.8 to −10.0‰). These values argue for oxidation of dissolved sulfide produced during sulfate-limited TSR that presently characterizes the chemistry of springs further downstream in the Cerna Valley. The δ18O values of cave sulfates from Population 1 are consistent with oxidation under more oxic aqueous conditions than those of Population 2. δ34S values of cave sulfates within Population 3 (δ34S: 5.8 to 6.5‰) may be consistent with several scenarios (i.e., pyrite oxidation, oxidation of dissolved sulfide produced during methane-limited TSR coupled with O2-limited oxidation during SAS). However, comparatively 18O-enriched δ18OSO4 values (11.9 to 13.9‰) suggest the majority of this sulfate O was derived from atmospheric O2 in gas-phase oxidation prior to hydration. Thus, the combined use of oxygen- and sulfur-isotope systematics of sulfate minerals precipitated in a variety of cave settings along Cerna Valley may serve as an example of how more complex cave systems can be deconvoluted to allow for more complete recognition of the range of processes and parameters that may be involved in SAS.


Improving sinkhole hazard models incorporating magnitudefrequency relationships and nearest neighbor analysis, 2011, Galve Jorge P. , Remondo Juan, Gutié, Rrez Francisco

This work presents a methodology for elaborating sinkhole hazard models that incorporate the magnitude and frequency relationships of the subsidence process. The proposed approach has been tested in a sector of the Ebro valley mantled evaporite karst, where sinkholes, largely induced by irrigation practices, have a very high occurrence rate (>50 sinkholes/km2/yr). In this area, covering 10 km2, a total of 943 new cover collapse sinkholes were inventoried in 2005 and 2006. Multiple susceptibility models have been generated analyzing the statistical relationships between the 2005 sinkholes and different sets of variables, including the nearest sinkhole distance. The quantitative evaluation of the prediction capability of these models using the 2006 sinkhole population has allowed the identification of the method and variables that produce the most reliable predictions. The incorporation of the indirect variable nearest sinkhole distance has contributed significantly to increase the quality of the models, despite simplifying the modeling process by using categorical rather than continuous variables. The best susceptibility model, generated with the total sinkhole population and the selected method and variables, has been transformed into a hazard model that provides minimum estimates of the spatial–temporal probability of each pixel to be affected by sinkholes of different diameter ranges. This transformation has been carried out combining two equations derived from the more complete 2006 sinkhole population; one of them expressing the expected spatial–temporal probability of sinkhole occurrence and the other the empirical magnitude and frequency relationships generated for two different types of land surfaces, which control the strength of the surface layer and the size of the sinkholes. The presented method could be applied to predict the spatial–temporal probability of events with different magnitudes related to other geomorphic processes (e.g. landslides).


Structural and host rock controls on the distribution, morphology and mineralogy of speleothems in the Castanar Cave (Spain), 2011, Alonsozarza A. M. , Martinperez A. , Martingarcia R. , Gilpena I. , Melendez A. , Martinezflores E. , Hellstrom J. , Munozbarco P.

The Castanar Cave (central western Spain) formed in mixed carbonate-siliciclastic rocks of Neoproterozoic age. The host rock is finely bedded and shows a complex network of folds and fractures, with a prevalent N150E strike. This structure controlled the development and the maze pattern of the cave, as well as its main water routes. The cave formed more than 350 ka ago as the result of both the dissolution of interbedded carbonates and weathering of siliciclastic beds, which also promoted collapse of the overlying host rock. At present it is a totally vadose hypergenic cave, but its initial development could have been phreatic. The cave's speleothems vary widely in their morphology and mineralogy. In general, massive speleothems (stalactites, stalagmites, flowstones, etc.) are associated with the main fractures of the cave and bedding planes. These discontinuities offer a fairly continuous water supply. Other branching, fibrous, mostly aragonite speleothems, commonly occur in the steeper cave walls and were produced by capillary seepage or drip water. Detailed petrographical and isotope analyses indicate that both aragonite and calcite precipitated as primary minerals in the cave waters. Primary calcite precipitated in waters of low magnesium content, whereas aragonite precipitated from magnesium-rich waters. Differences in isotope values for calcite (-5.2‰ for ?18O and -9.6‰ for ?13C) and aragonite (?18O of -4.5‰ and ?13C of -3.5‰ ) can be explained by the fact that the more unstable mineral (aragonite) tends to incorporate the heavier C isotope to stabilize its structure or that aragonite precipitates in heavier waters. Changes in the water supply and the chemistry and instability of aragonite caused: (1) inversion of aragonite to calcite, which led to the transformation of aragonite needles into coarse calcite mosaics, (2) micritization, which appears as films or crusts of powdery, opaque calcite, and (3) dissolution. Dolomite, huntite, magnesite and sepiolite were identified within moonmilk deposits and crusts. Moonmilk occurs as a soft, white powder deposit on different types of speleothems, but mostly on aragonite formations. Huntite and magnesite formed as primary minerals, whereas dolomite arose via the replacement of both huntite and aragonite. Owing to its variety of speleothems and location in an area of scarce karstic features, the Castanar Cave was declared a Natural Monument in 1997 and is presently the target of a protection and research programme. Although the main products formed in the cave and their processes are relatively well known, further radiometric data are needed to better constrain the timing of these processes. For example, it is difficult to understand why some aragonite speleothems around 350 ka old have not yet given way to calcite, which indicates that the environmental setting of the cave is still not fully understood. 


Hydroecogeochemical effects of an epikarst ecosystem: case study of the Nongla Landiantang Spring catchment, 2012, Shen L. , Deng X. , Jiang Z. , Li T.

A typical small-scale epikarst ecosystemusually consists of an epikarst zone, soil and vegetation. In this study, to determine the hydro-eco-geochemical effects of an epikarst ecosystem in subtropical humid area, the samples of vegetation, soil, soil microbes, rainfall, throughfall, stem flow, soil water and epikarst springs of Nongla Village, Mashan County, Guangxi in China were collected and analyzed. The research results have shown in the epikarst ecosystem, the conductivity, temporary hardness and total carbon increased continuously in hydro-ecochemical cycle; the vegetation–soil system conducted the transformation and transference of carbon in hydro-ecochemical cycle; the vegetation layer was the major source for organic carbon, while the soil layer was of the important chemical field for the conversion of organic/inorganic carbon and HCO3 –, which would affect the epikarst dynamical system; for most ions, the vegetation layer and shallow soil layer presented more leaching effect than absorption, in contrast, the deep soil layer behaved oppositely. The vegetation layer and shallow soil layer leached ions, and deep soil layer absorbed them. With the plant community presenting in a positive succession, the epikarst ecosystem trended to be stabilized gradually, which made the hydro-eco-geochemical effects to be adjusted and controlled more effectively


Alternative method of analysis of results of 3D terrestrial laser scanning (comment to the article Contribution to a rock block slide examination by a model of mutual transformation of point clouds, Acta Carsologica 38,1), 2012, Perne, Matija
The article Konic et al. (2009) describes efforts to find out if the rock block on which the castle of Črni kal is situated slid away from the Kraški rob wall. 3D terrestrial laser scanning has been used to determine positions of many points on both presumed contact surfaces and 12-parameter affine transformation that transforms the cloud of points from one wall into another has been found. The deviation between matching point clouds has been used as a test of the original hypothesis. It has been concluded that the rock block did slide. Some of the data from the article are re-analysed using another numerical method. A 6-parameter translation composed with rotation that best transforms the 12 published points from the rock block wall into their counterparts on the Kraški rob wall is found. The original hypothesis is confirmed and some additional insight into the block slide is revealed.

Environmental Hydrogeological Study of Louros watershed, Epirus, Greece, 2012, Konstantina Katsanou

The present study aims to describe and characterize the Ionian zone karst formation concerning the karstification grade of carbonate formations and the development of aquifers, through the hydrogeological study of Louros River drainage basin, considering hydrological, hydrogeological and meteorological data, as well as major, trace element, rare earth element and isotope concentrations. It also aims to investigate basic karst properties such as storativity, homogeneity, infiltration coefficients and the parameters of the Louros basin hydrological balance.

To accomplish this aim daily discharge measurements obtained from Public Power Corporation at the Pantanassa station during the years 1956-1957, along with random discharge measurements from 15 springs along the basin performed by IGME between the years 1979-1989, daily meteorological data from 18 stations and 18 sets of potentiometric surface measurements from 38 sites were compiled. Additionally, chemical analyses on major and trace element concentrations of 42 rock samples and of five sets of water samples from 64 sampling sites, along with fourteen sets of successive periods in order to study the seasonal variation in the chemical composition of 11 springs and REE concentrations of 116 water samples. Moreover isotope ratios from 129 rain samples collected at five different altitudes, 331 samples of surface and groundwater samples, radon measurements on 21 groundwater samples and microbiological on 46 samples of surface and groundwater were evaluated. Daily runoff and random spring discharge missing data were completed applying the SAC-SMA and MODKARST simulation algorithms and the values of these parameters for the duration of the research (2008-2010) were predicted. The accuracy of the predicted values was tested applying statistical methods but also against observed values from in situ measurements performed during the same period (2008-2010).

Louros River drainage basin is located at the southern part of Epirus and covers an area of 953 km2. It is elongated and together with the adjacent basin of River Arachthos they constitute the major hydrographic systems discharging in the Amvrakikos Gulf. The main morphological features of the basin are elongated mountain ranges and narrow valleys, which are the result of tectonic and other geological processes mainly controlled by the limestone-“flysch” alternations. The length of the river’s major channel, which is parallel to the major folding direction (NNW-SSE), is 73.5 km. The mountainous part of the hydrogeological basin covers an area of 400 km2 and its endpoint was set at the Pantanassa station, where discharge measurements are performed. The underground limits of the basin coincides with the surface one, defined by the flysch outcrops at the western margin of the Ziros-Zalongo fault zone to the South, the application of isotope determinations and hydraulic load distribution maps at the North and East.

Geologically, Louros River drainage basin is composed of the Ionian zone formations. Triassic evaporites constitute the base of the zone overlain by a thick sequence of carbonate and clastic sedimentary rocks deposited from the Late Triassic to the Upper Eocene. In more detail, from base to top, the lithostratigraphical column of the zone includes dolomite and dolomitic limestone, Pantokrator limestone, Ammonitico Rosso, Posidonia Shales, Vigla limestone, Upper Senonian limestone, Palaeocene-Eocene limestone and Oligocene “flysch”. The major tectonic features of the regions are folds with their axes trending SW-NE at the northern part and NNW-SSE to NNE-SSW southern of the Mousiotitsa-Episkopiko-Petrovouni fault system and the strike-slip fault systems of Ziros and Petousi.

The evaluation of the daily meteorological data revealed that December is the most humid month of the year followed by January, whereas July and August are the driest months. Approximately 40-45% of the annual precipitation is distributed during the winter time and 30% during autumn. The mean annual precipitation ranges from 897.4 to 2051.8 mm and the precipitation altitude relationship suggests an increased precipitation with altitude at a rate of 84 mm/100 m. The maximum temperature is recorded during August and it may reach 40°C and the minimum during January. The temperature variation with the altitude is calculated at 0.61°C/100 m. The maximum solarity time is 377.8 h, recorded during July at the Arta station. December displays the highest relative humidity with a value of 84.2% recorded again at the Arta station. The highest wind velocity values are recorded at the Preveza station and similar velocities are also recorded at the Ioannina station. The real evapotranspiration in Louros drainage basin ranges between 27-39%. The potential evapotranspiration was calculated from the Ioannina station meteorological data, which are considered more representative for Louros basin, at 785.8 mm of precipitation according to Thornthwaite and at 722.0 mm according to Penman-Monteith.

According to the SAC-SMA algorithm the total discharge (surficial and underground) for the years 2008-2010 ranges between 61-73% of the total precipitation. The algorithm simulates the vertical percolation of rainwater in both unsaturated and saturated zones taking into account 15 parameters including the tension water capacity of the unsaturated zone, the maximum water storage capacity of both unsaturated and saturated zones, the water amount escaping into deeper horizons and not recorded at the basin’s outlet, the percentage of impermeable ground which is responsible for instant runoff, etc. These parameters are correlated to the hydrograph and are recalculated according to it. Two interesting aspects were pointed out from the discharge measurements and the algorithm application. The first is related to the maximum amount of free water, which can be stored at the basic flow of the karstic system, which is very high for the whole basin, reaching 1200 mm of precipitation and the second is the amount of water filtered to the deeper horizons, which reaches 0.098.

The discharge of individual karstic units was simulated applying the specialized MODKARST code. The code, which transforms precipitation to discharge resolving mathematical equations of non-linear flow using the mass and energy balance, successfully completed the time series of available data of spring discharge measurements for the period between the years 2008-2010.

Additionally, a number of useful parameters including spring recharge, delay period between precipitation and discharge, the storage capacity of the discharge area were also calculated by the MODKARST code. These data enabled the calculation of the annual infiltration coefficient for each one of the 15 springs and for the whole basin; the latter was found to range between 38-50% of annual precipitation. The total supply area was estimated approximately at 395 km2, which is consistent with the area of Louros hydrogeological basin calculated from hydrogeological data.

The 18 sets of water table measurements, each one corresponding to a different period, revealed that the aquifers of the intermediate part of Louros basin, which are developed in Quaternary alluvial sediments, are laterally connected to the carbonate formations of the individual karstic spring units, forming a common aquifer with a common water table.

Groundwater flow follows a general N-S direction from the topographic highs to the coastal area with local minor shifts to NE-SW and NW-SE directions. The artificial lake at the position of the Public Power Corporation’s Dam at the south of the region is directly connected to the aquifer and plays an important role in water-level variation. The water table contours display a higher gradient to the southern part due to the decreased hydraulic conductivity of the limestones close to Agios Georgios village. The decreased hydraulic conductivity is believed to be the reason for the development of the homonymous spring although the hydraulic load distributions suggest the extension of the aquifer to the south and a relation to the water level in Ziros Lake, boreholes and the Priala springs. The hydraulic gradient in the broader region ranges between 4-16‰. The absolute water level variation between dry and humid season ranges from 2 m at the South to 15-20 m to the North with an average of 9 m.

The hydrological balance of Louros River mountainous basin according to the aforementioned data is calculated as follows: The total precipitation between the years 2008-2010 ranged between 5.67E+08-9.8E+08 m3 and the discharge at Pantanassa site between 3.47E+08-6.83E+08 m3. The real evapotransiration ranged between 29-39% of the precipitation. The total discharge (runoff and groundwater) accounted for 61-73% of the precipitation, whereas the basic flow due to the percolation ranged between 34-38%. Considering a mean water level variation of 9 m, between the dry and humid season, the water amount constituting the local storage is 2025Ε+07 m3.

Statistical evaluation on spring discharge data and the recession curves analysis revealed three distinct levels with diverse karstic weathering along Louros basin coinciding to the upper, intermediate and low flow of Louros River, respectively. The developed karstic units are generally complex but simple individual units develop as well. The response of spring discharge to the stored water amounts is immediate but with relatively large duration suggesting the storage of large quantities of water and a well-developed system of karstic conduits, which however has not yet met its complete evolution. The karst spring’s units are homogeneous and each one is distinguished from different recession coefficients.

The three levels of flow are also distinguished from the duration curves, which point to individual units upstream, complex units receiving and transmitting water to the adjacent ones in the middle part and complex that only receive water from the upper. This distinguishment is also enhanced by the groundwater’s major ion concentrations, which reveal Ca-HCO3 water-type upstream, along with the isotopic composition at the same part. The prevalent Ca-HCO3-Cl-SO4 water-type in the middle part, the Na-Ca-Cl-SO4 water-type downstream and isotope variation confirms this distinguishment. Moreover, REE variation is also consistent with the three levels. The assumption of relatively large stored water reserves, which contribute to analogous “memory” of spring karstic units, as pointed out by autocorreletion functions is enhanced from SAC-SMA algorithm which premises an increased capacity at the lower zone of basic flow, as well as from the hydrochemical and isotopic composition of groundwater. Monitoring of the seasonal variation in groundwater composition revealed minor variations of hydrochemical parameters and remarkably stable isotopic composition. Both aspects can be explained by the existence of a considerable water body acting as a retarder to external changes.

The crosscorrelation functions suggest a well-developed karstic system, which however has not yet reached its complete maturity also confirmed from field observations. The same conclusion is extracted from the homogeneous evolution at the interval of each karstic unit as demonstrated from recession curves on spring hydrographs.

The results from hydrochemical analyses also revealed the effect of evaporitic minerals and phosphate-rich rocks in groundwater composition and confirmed the hydraulic relationships between surface and groundwater.

The study of the isotopic composition also contributed to exclude the potential connection between the Ioannina and Louros basins, confirmed the meteoric origin of groundwater and revealed the effect of seawater in the chemical composition of few sampling sites.

The microbiological research only revealed minor incidents of contamination and significant attenuation of microorganisms during periods of high discharge.


Major stone forest, litomorphogenesis and development of typical shilin (Yunnan, China), 2012, Knez M. , Slabe T. , Liu H.

Major stone forest excellently reveals most characteristics of the formation of the various stone forests. The relatively thick stratification and evenly composed rock clearly display the development of stone forests from subsoil karren. This is evident from the shape of individual parts of the stone forest and the shape and rock relief of pillars that comprise the forest. It is the most typical example of development of karren from subsoil to rain and vegetation exposed stone forest. With it we can compare stone forests shaped on different rock and geomorphological and hydrological conditions. Type of rock is clearly reflected in the intensity of corrosion and erosion and with it in the formation and morphological appearance of individual stone pillars and larger blocks of rock. The rock relief on the pillars in stone forests reveals the interwoven traces of the original shaping of the rock below soil and sediment, of the lowering of the level of soil and sediment, and of the younger but distinct transformation of pillars by rainwater, which naturally dominates on the tops. The exceptional character and picturesqueness of this karst phenomenon is the reason for the successful development of the stone forest as an international tourist attraction that was deservedly placed on the UNESCO world heritage list.


Major stone forest, litomorphogenesis and development of typical shilin (Yunnan, China), 2012, Knez Martin, Slabe Tadej, Liu Hong

Major stone forest excellently reveals most characteristics of the formation of the various stone forests. The relatively thick stratification and evenly composed rock clearly display the development of stone forests from subsoil karren. This is evident from the shape of individual parts of the stone forest and the shape and rock relief of pillars that comprise the forest. It is the most typical example of development of karren from subsoil to rain and vegetation exposed stone forest. With it we can compare stone forests shaped on different rock and geomorphological and hydrological conditions. Type of rock is clearly reflected in the intensity of corrosion and erosion and with it in the formation and morphological appearance of individual stone pillars and larger blocks of rock. The rock relief on the pillars in stone forests reveals the interwoven traces of the original shaping of the rock below soil and sediment, of the lowering of the level of soil and sediment, and of the younger but distinct transformation of pillars by rainwater, which naturally dominates on the tops. The exceptional character and picturesqueness of this karst phenomenon is the reason for the successful developmentof the stone forest as an international tourist attraction that was deservedly placed on the UNESCO world heritage list.


High Resolution Seismic Reflection Methods to Detect Near Surface Tuff-Cavities: A Case Study in the Neapolitan Area, Italy, 2013, Di Firoe V. , Angelino A. , Passaro S. , Bonanno A.

 

The Neapolitan region of Italy is plagued by the presence of shallow manmade cavities in lithoid tuffs that cause problems for communities because they produce building damages and loss of human lives. A high resolution P-wave seismic-reflection technique was successfully used to define a cavity 6 m by 10 m in horizontal dimensions and with a height of about 6 m located in a tuff layer 10 to 19 m below ground level. Such a cavity was located at Afragola (near Naples) where the local geology is typical of the Neapolitan area. The seismic dataset was acquired by using end-on spread geometry, with 0.25 m spacing for shots and 0.5 m for receivers. The application of band–pass filtering (30–150 Hz) allowed us to remove incoherent noise from the data, while an additional equivalent slope (Vs21) of 0.005 s m21 cut in the FK transform results in ground-roll noise removal. Both the acquisition and processing methods have been necessary to investigate and define the shape and dimensions of the targeted cavity


A laboratory study of tracer tomography, 2013, Brauchler R. , Bhm G. , Leven P. , Dietrich C. , Sauter M.

A tracer tomographic laboratory study was performed with consolidated fractured rock in three-dimensional space. The investigated fractured sandstone sample was characterized by significant matrix permeability. The laboratory transport experiments were conducted using gas-flow and gas-tracer transport techniques that enable the generation of various flow-field patterns via adjustable boundary conditions within a short experimental time period. In total, 72 gas-tracer (helium) tests were performed by systematically changing the injection and monitoring configuration after each test. For the inversion of the tracer breakthrough curves an inversion scheme was applied, based on the transformation of the governing transport equation into a form of the eikonal equation. The reliability of the inversion results was assessed with singular value decomposition of the trajectory density matrix. The applied inversion technique allowed for the three-dimensional reconstruction of the interstitial velocity with a high resolution. The three-dimensional interstitial velocity distribution shows clearly that the transport is dominated by the matrix while the fractures show no apparent influence on the transport responses.


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