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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 piezometric surface is 1. the imaginary surface to which water from a given aquifer will rise under its full static head [10]. 2. defined by the elevation to which water will rise in artesian wells or wells penetrating confined aquifers [16]. see also potentiometric surface.?

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

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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 signal (Keyword) returned 95 results for the whole karstbase:
Showing 91 to 95 of 95
Corrosion morphology and cave wall alteration in an Alpine sulfuric acid cave (Kraushöhle, Austria), 2012, Plan Lukas, Tschegg Cornelius, De Waele Jo Spö, Tl Christoph

Whereasmost karstic cavesworldwide are formed by carbonic acid, a small but significant number of sub-surface cavities are the product of sulfuric acid speleogenesis (SAS). In the Eastern Alps, no cave has so far been attributed to this type. In this multidisciplinary studywe demonstrate that Kraushöhle in northern Styriawas indeed formed by SAS. The cave pattern shows individual chambers, 3D-mazes and blind galleries, as well as typical SAS morphologies such as cupolas, gypsum replacement pockets, corrosion notches and convection niches. “Ceiling pendant drip holes” are described here for the first time and these corrosion features are fully consistent with the SAS model. Other features of Kraushöhle include thick gypsum deposits with strongly depleted δ34S values and other minerals – mostly sulfates – indicating highly acidic conditions. We also studied acid–rock interaction processes giving rise to widespread corrosion and concomitant replacement by gypsum. Petrographic and geochemical analyses reveal the presence of a distinctive alteration layer of highly increased porosity at the interface between the host limestone and the secondary gypsum. Dissolution and replacement of the limestone was fast enough to prevent the development of C and O isotopic alteration halos but resulted in selective leaching of elements. This stable isotope signal is thus different from the pronounced isotope gradient commonly observed in CO2-dominated hypogenic caves. Petrographic observations reveal that the limestone–gypsum replacement was a nearly constant volume process.Whereasmost karstic cavesworldwide are formed by carbonic acid, a small but significant number of sub-surface cavities are the product of sulfuric acid speleogenesis (SAS). In the Eastern Alps, no cave has so far been attributed to this type. In thismultidisciplinary studywe demonstrate that Kraushöhle in northern Styriawas indeed formed by SAS. The cave pattern shows individual chambers, 3D-mazes and blind galleries, as well as typical SAS morphologies such as cupolas, gypsum replacement pockets, corrosion notches and convection niches. “Ceiling pendant drip holes” are described here for the first time and these corrosion features are fully consistent with the SAS model. Other features of Kraushöhle include thick gypsum deposits with strongly depleted δ34S values and other minerals – mostly sulfates – indicating highly acidic conditions. We also studied acid–rock interaction processes giving rise to widespread corrosion and concomitant replacement by gypsum. Petrographic and geochemical analyses reveal the presence of a distinctive alteration layer of highly increased porosity at the interface between the host limestone and the secondary gypsum. Dissolution and replacement of the limestone was fast enough to prevent the development of C and O isotopic alteration halos but resulted in selective leaching of elements. This stable isotope signal is thus different from the pronounced isotope gradient commonly observed in CO2-dominated hypogenic caves. Petrographic observations reveal that the limestone–gypsum replacement was a nearly constant volume process.


Mixing of water in a carbonate aquifer, southern Italy, analysed through stable isotope investigations, 2013, Petrella E. , Celico F.

Mixing of water was analysed in a carbonate aquifer, southern Italy, through stable isotope investigations (18O,δ2H). The input signal (rainwater) was compared with the isotopic content of a 35-meter groundwater vertical profile, over a 1-year period. Within the studied aquifer, recharge and flow are diffuse in a well-connected fissure network.

At the test site, the comparison between input and groundwater isotopic signals illustrates that no efficient mixing takes place in the whole unsaturated zone, between the fresh infiltration water and the stored water.

When analysing the stable isotope composition of groundwater, significant variations were observed above the threshold elevation of 1062 m asl, while a nearly constant composition was observed below the same threshold. Thus, temporal variations in stable isotope composition of rainwater are completely attenuated just in the deeper phreatic zone.

On the whole, taking into consideration also the results of previous studies in the same area, the investigations showed that physical characteristics of the carbonate bedrock, as well as aquifer heterogeneity, are factors of utmost importance in influencing the complete mixing of water. These findings suggest a more complex scenario at catchment scale.


TRITIUM AND H, O AND C STABLE ISOTOPES AS A TOOL FOR TRACKING OF WATER CIRCULATION IN THE NIEDŹWIEDZIA CAVE SYSTEM (SUDETES, POLAND), 2013, Gą, Siorowski M. Hercman H.

 

Water circulation in Niedźwiedzia Cave system is complicated. The system is fed by direct infiltration of precipitation, infiltration from the surface stream and, possibly, by rising flow from deep sources. The cave is drained by system of karst springs in the Kleśnica stream valley, but some part of water flows across border ridge and occurs in Morava stream valley, Czech Republic (Ciężkowski et al. 2009). We tried to use tritium and stable isotopes to describe hydrology of the cave system and analyzed 155 water samples for stable isotopes and 38 water samples for tritium content. The Niedźwiedzia Cave system is composed of three levels of halls and galleries. In the upper level, stable isotope composition in drip water plots close to the local meteoritic water line (LMWL) on the δ18O vs δD diagram. It varies during the year similar to stable isotope composition of precipitation (i.e. low δ18O values during winters and higher δ18O during summers). The delay between isotopic signal in precipitation and drip water is ~10–14 days and this can be interpreted as a time of infiltration from the surface to the cave upper level. The correlation between isotopic composition of precipitation and drip water is not observed in the lower level of the cave system. There isotopic composition of drip water is more stable during the year. We use tritium dating method to estimate the age of this water. It has shown that infiltration time to the lower level is 1.4±0.3 year. The “oldest” water was found in karst spring draining the cave system. The estimated transit time is 3–4 years and suggest admixture of some “old” water that was not sampled in the cave.


Seismic study of the low-permeability volume in southern France karst systems, 2013, Galibert P. Y. , Valois R. , Mendes M. , Gurin R.

Locating groundwater in deep-seated karst aquifers is inherently difficult. With seismic methods, we studied the upper epikarst and the underneath low-permeability volume (LPV) of several karst systems located in the southern Quercy and Larzac regions of France and found that refraction tomography was effective only in the epikarst and not in the LPV. We evaluated a 3D case study using a combination of surface records and downhole receivers to overcome this limitation. This 3D approach unveiled a set of elongated furrows at the base of the epikarst and identified heterogeneities deep inside the LPV that may represent high-permeability preferred pathways for water inside the karst. To achieve the same result when no borehole was available, we studied seismic amplitudes of the wavefield, recognizing that wave-induced fluid flow in low-permeability carbonates is a driving mechanism of seismic attenuation. We developed a workflow describing the heterogeneity of the LPV with spectral attributes derived from surface-consistent decomposition principles, and we validated its effectiveness at benchmark locations. We applied this workflow to the 3D study and found a low-amplitude signal area at depth; we interpreted this anomaly as a water-saturated body perched above the aquifer.


Characterisation and modelling of conduit restricted karst aquifers – Example of the Auja spring, Jordan Valley, 2014, Schmidta Sebastian, Geyera Tobias, Guttmanb Joseph, Mareic Amer, Riesd Fabian, Sauter Martin

The conduit system of mature karstified carbonate aquifers is typically characterised by a high hydraulic conductivity and does not impose a major flow constriction on catchment discharge. As a result, discharge at karst springs is usually flashy and displays pronounced peaks following recharge events. In contrast, some karst springs reported in literature display a discharge maximum, attributed to reaching the finite discharge capacity of the conduit system (flow threshold). This phenomenon also often leads to a non-standard recession behaviour, a so called “convex recession”, i.e. an increase in the recession coefficient during flow recession, which in turn might be used as an indicator for conduit restricted aquifers. The main objective of the study is the characterisation and modelling of those hydrogeologically challenging aquifers. The applied approach consists of a combination of hydrometric monitoring, a spring hydrograph recession and event analysis, as well as the setup and calibration of a non-linear reservoir model. It is demonstrated for the Auja spring, the largest freshwater spring in the Lower Jordan Valley. The semi-arid environment with its short but intensive precipitation events and an extended dry season leads to sharp input signals and undisturbed recession periods. The spring displays complex recession behaviour, exhibiting exponential (coefficient α) and linear (coefficient β) recession periods. Numerous different recession coefficients α were observed: ∼0.2 to 0.8 d−1 (presumably main conduit system), 0.004 d−1 (fractured matrix), 0.0009 d−1 (plateau caused by flow threshold being exceeded), plus many intermediate values. The reasons for this observed behaviour are the outflow threshold at 0.47 m3 s−1 and a variable conduit–matrix cross-flow in the aquifer. Despite system complexity, and hence the necessity of incorporating features such as a flow threshold, conduit–matrix cross-flow, and a spatially variable soil/epikarst field capacity, the developed reservoir model is regarded as relatively simplistic. As a number of required parameters were calculated from the hydrogeological analysis of the system, it requires only six calibration parameters and performs well for the highly variable flow conditions observed. Calculated groundwater recharge in this semi-arid environment displays high interannual variability. For example, during the 45-year simulation period, only five wet winter seasons account for 33% of the total cumulative groundwater recharge.


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