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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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Featured articles from Cave & Karst Science Journals
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 geochemistry (Keyword) returned 213
Showing 196 to 210 of 213
Biospeleogenesis, 2013, Barton, H. A.

Microorganisms have shaped the world around us, yet their role in karst processes and speleogenesis remains poorly understood. Biospeleogenesis is the formation of subsurface cavities and caves through the activities of microorganisms, by either respiratory (redox) or metabolic chemistries. In carrying out energy acquisition and the metabolic processes of growth, microorganisms change the local geochemistry of the environment. Such activities can dramatically accelerate speleogenesis and even lead to cave formation in geochemical environments that would otherwise not be conducive to dissolution. The aim of this chapter is to help the reader understand the importance of microbial activity in geochemistry and how such activity can lead to the formation and morphology of caves. The chapter then describes the role that microorganisms are known to have in speleogenesis (carbonic and sulfuric acid biospeleogenesis), hints that such activity may be occurring in newly described cave systems (iron biospeleogenesis), and a potential role in other cave systems (quartzite biospeleogenesis). It is hoped that the reader will gain an understanding of what motivates microorganisms to dramatically change their environment, understand the potential geochemical conditions where such activity could occur, and allow the informed geologist to make predictive statements as to the potential of, and for, biospeleogenesis 


Cave aerosols: distribution and contribution to speleothem geochemistry, 2013, Dredge J. , Fairchild I. J. , Harrison R. M. , Fernandezcortes A. , Sanchezmoral S. , Jurado V. , Gunn J. , Smith A. , Spö, Tl Ch. , Mattey D. , Wynn P. M. , Grassineau N.

There is developing interest in cave aerosols due to the increasing awareness of their impacts on the cave environment and speleothem; this paper provides the first attempt to synthesize the issues. Processes of cave aerosol introduction, transport, deposition, distribution and incorporation are explored, and reviewed from existing literature. Key issues of specific aerosol processes of distribution and production as well as cave location and morphology effects are highlighted through the presentation of preliminary monitoring data. This study identifies the strong relationship between cave ventilation, cave aerosols and their consequent spatial distribution. The contribution of cave aerosol deposition to speleothem geochemistry is modelled and evaluated using a mass balance framework. As an example, speleothem trace element data from Obir Cave (Austria) are compared with aerosol inputs to evaluate their significance. The mass balance study demonstrates that generally, under normal continuous growth and environmental conditions aerosol deposition will be of only minor importance. However, it highlights specific scenarios in which aerosol contributions will be significant: speleothem hiatuses (or slow growth), high aerosol deposition, and secondary microbiological feedback.


Stable isotope (O and C) geochemistry of non-sulfide ZnPb deposits; case study: Chah-Talkh non-sulfide ZnPb deposit (Sirjan, south of Iran), 2013, Rezaeian A. , Rasa I. , Amiri A. , Jafari M. R.

The study of oxygen and carbon isotopic ratios has gained importance to determine the origin of ore-bearing fluids, carbon origin, and also to determine the formation temperature of non-sulfide Pb and Zn minerals. In order to determine the origin of fluids and carbon existing in Zn carbonate minerals in Chah-Talkh deposit, initially the amounts of δ18OSMOW and δ13CPDB changes in various zinc minerals in important deposits in Iran and the world were studied, and then by comparing these values in Chah-Talkh deposit with those of other deposits, the origin of fluids responsible for ore forming, carbon, and formation temperature of Chah-Talkh deposit was determined. The range of δ18OSMOW changes in smithsonite mineral in non-sulfide lead and zinc deposits varies from 18.3 to 31.6 ‰, and δ18OSMOW in hydrozincite mineral varies from 7.8 to 27 ‰. Due to the impossibility of smithsonite sampling from Chah-Talkh deposit (due to it being fine-grained and dispersed), hydrozincite minerals which have high isotopic similarities with smithsonite are used for the isotopic analysis of carbon and oxygen. The range of δ18OSMOW changes in hydrozincite mineral of Chah-Talkh deposit varies from 7.8 to 15.15‰, which places in the domain of metamorphic water. The extensiveness of δ18OSMOW changes in Chah- Talkh indicates the role of at least two fluids in the formation of non-sulfide minerals. The obtained formation temperature of non-sulfide minerals (hydrozincite) in Chah- Talkh deposit is 70 to 100 °C, which indicates the role of metamorphic fluids in the formation of deposit. Complete weathering of sulfide minerals to a depth of 134 m confirms the role of rising metamorphic fluids in the formation of non-sulfide minerals. The δ13CPDB values of Chah-Talkh deposit are set in the range of atmospheric CO2 and carbonate rocks, in which the existence of atmospheric CO2 indicates the role of atmospheric fluids, and the existence of carbonate carbon rock indicates of the role of metamorphic fluids in the precipitation of non-sulfide Zn minerals.


Water-gas-rock interactions and seasonal control of geochemical environments in the epikarstic zone of the Pennyroyal Plateau, Kentucky, USA, 2013, Groves Chris, Polk Jason, Miller Ben, Bolster Carl

Water-gas-rock interactions and seasonal control of geochemical environments in the epikarstic zone of the Pennyroyal Plateau, Kentucky, USA, 2013, Groves Chris, Polk Jason, Miller Ben, Bolster Carl

COMPLEX EPIKARST HYDROLOGEOLOGY AND CONTAMINANT TRANSPORT IN A SOUTH-CENTRAL KENTUCKY KARST LANDSCAPE, 2013, Polk J. S. , Vanderhoff S. , Groves C. , Miller B. , Bolster C.

 

The movement of autogenic recharge through the shallow epikarstic zone in soil-mantled karst aquifers is important in understanding recharge areas and rates, storage, and contaminant transport processes. The groundwater in agricultural karst areas, such as Kentucky’s Pennyroyal Plateau, which is characterized by shallow epikarst and deeper conduits flow, is susceptible to contamination from organic soil amendments and pesticides. To understand the storage and flow of autogenic recharge and its effects on contaminant transport on water flowing to a single epikarst drain in Crump’s Cave on Kentucky’s Mississippian Plateau, we employed several techniques to characterize the nature and hydrogeology of the system. During 2010–2012, water samples and geochemical data were collected every four hours before, during, and between storm events from a waterfall in Crumps Cave to track the transport and residence time of epikarst water and organic soil amendments during variable flow conditions. Geochemical data consisting of pH, specific conductivity, temperature, and discharge were collected continuously at 10-minute intervals, along with rainfall amounts. In addition, stable isotope data from rainfall, soil water, and epikarst water were collected weekly and during storm events to examine storage and recharge behavior of the system. The changes in geochemistry indicate simultaneous storage and transport of meteoric water through epikarst pathways into the cave, with rapid transport of bacteria occurring through the conduits that bypass storage. The isotopic data indicate that recharge is rapidly homogenized in the epikarst, with storage varying throughout the year based on meteorological conditions. Results indicate current best management practices in agricultural karst areas need to be revisited to incorporate areas that do not have surface runoff, but where contaminants are transported by seepage into local aquifers.


Geochemistry and isotope geochemistry of the Monfalcone thermal waters (northern Italy): inference on the deep geothermal reservoir, 2013, Petrini R. , Italiano F. , Ponton M. , Slejko F. F. , Aviani U. , Zini L.

Geochemical investigations were carried out to define the origin of the low- to moderate-temperature thermal waters feeding the Monfalcone springs in northern Italy. Chemical data indicate that waters approach the composition of seawater. Mixing processes with cold low-salinity waters are highlighted. The δ18O and δD values are in the range −5.0 to −6.4 ‰, and −33 to −40 ‰, respectively, suggesting the dilution of the saline reservoir by karst-type freshwaters. A surplus of Ca2+ and Sr2+ ions with respect to a conservative mixing is ascribed to diagenetic reactions of the thermal waters with Cretaceous carbonates at depth. The measured Sr isotopic composition (87Sr/86Sr ratio) ranges between 0.70803 and 0.70814; after correction for the surplus Sr, a 87Sr/86Sr ratio indicating Miocene paleo-seawater is obtained. The dissolved gases indicate long-lasting gas–water interactions with a deep-originated gas phase of crustal origin, dominated by CO2 and marked by a water TDIC isotopic composition in the range −5.9 to−8.8 and helium signature with 0.08 < R/Ra < 0.27, which is a typical range for the crust. A possible scenario for the Monfalcone thermal reservoir consists of Miocene marine paleowaters which infiltrated through the karstic voids formed within the prevalently Cretaceous carbonates during the upper Eocene emersion of the platform, and which were entrapped by the progressive burial by terrigenous sediments.


Isotopes of Carbon in a Karst Aquifer of the Cumberland Plateau of Kentucky, USA, 2013, Florea Lee J.

In this study, the concentration and isotopic composition of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) are measured in the karst groundwater of the Otter Creek watershed of the Cumberland Plateau of Kentucky, USA. Comparisons among these data and with the geochemistry of carbonate and gypsum equilibrium reactions reveal that DOC concentration is inversely related to discharge, multiple reaction pathways provide DIC with isotopic enrichment that may be directly related to mineral saturation, and oxidation of reduced sulfur is possible for dissolution. DOC is derived from C3 vegetation with an average δ13C DOC of ‒27‰. DIC in groundwater is derived from both pedogenic CO2  and HCO3 - from dissolved carbonate. At input sites to the karst aquifers DIC concentrations are expectedly low, less than 1 mmol/L, in waters that are undersaturated with respect to calcite. At the output of these karst aquifers DIC concentrations reach 3 mmol/L in waters that are at or above calcite saturation. Values of δ13C DIC range between ‒6.3 and ‒12.4‰ with CO2 degassing and calcite precipitation at some sites obfuscating a simple relationship between δ13C DIC, discharge, and mineral saturation. In addition, concentrations of DIC in sulfur seeps within the watershed range between 2–7 mmol/L with δ13C DIC values in some samples skewed more toward the anticipated value of carbonate bedrock than would be expected from reactions with carbonic acid alone. This suggests that the oxidation of reduced sulfur from shallow oilfield brines liberates bedrock DIC through reactions with sulfuric acid.


Hypogene karst: speleogenetic mechanisms and geochemical methods of diagnostics , 2013, Dublyansky, Y.

Evidences of hypogenic speleogenesis in Slovenian caves , 2013, Otoničar, B.

 In Slovenia, known as the country of classical karst, thinking about caves of predominantly hypogenic origin have been treated almost as a heresy. Although we may agree that only on the basis of cave morphology and wall rock features parts of some “common” caves especially close to allogenic inflow and past epipheratic zones cannot be simply related to some past hypogenic phase of cave development (e. g. Osborne 2008; Knez & Slabe 2009) some caves in Slovenia host too many features diagnostic for hypogenic, hydrothermal or at least ascending water flow that such interpretations shouldn’t be considered.

We will present preliminary studies on caves from different karstic regions of Slovenia where cave morphology, wall rock features, mineralogy, general geological setting of the area and partly hydrogeology and hydrogeochemistry suggest, at least on a level of hypothesis, their partial development with hypogenic processes in a wider sense (sensu Palmer 2011). In each of the discussed karstic regions different phenomena diagnostic for some of the hypogenic processes prevails over the others.

In Jelovica high karstic plateau (Julian pre-Alps) and Raduha Mt. (Kamniško-Savinjske Alpe) many caves are locally decorated with big calcite crystals commonly found also as veins on the karstic surface.

The Vrh Svetih Treh Kraljev in Rovtarsko Hribovje, the Pre-alpine region in the western part of central Slovenia, hosts few caves which channels exhibit ramiform and maze like orientation guided by faults and joints with wall rock features characteristic for dissolution with slowly flowing ascending water. A large part of at least one cave is developed in dedolomite while the biggest cave in the area has no known natural entrance. In addition, three wells in the area discharge “sulphuric” water.

In Slovenia many caves show wall rock features that can also be diagnostic for hypogenic speleogenesis or at least to ascending flow. However, such features are most often found in places where high fluctuation of karstic waters mainly with allogenic river inflow occurs. Perhaps some exceptions could be found in the foothills of Jelovica Plateau where especially in one particular maze or anastomotic cave (Jeralovo brezno) no evidence of substantial allogenic inflow occurs although in the lower parts some smaller channels are partly filled by predominately fine grained sandy stream related allogenic deposits.

For more detail information of the above mentioned karstic regions with potential traces of hypogenic spelogenesis see the guidebook of the excursions.


Biospeleogenesis, 2013,

Microorganisms have shaped the world around us, yet their role in karst processes and speleogenesis remains poorly understood. Biospeleogenesis is the formation of subsurface cavities and caves through the activities of microorganisms, by either respiratory (redox) or metabolic chemistries. In carrying out energy acquisition and the metabolic processes of growth, microorganisms change the local geochemistry of the environment. Such activities can dramatically accelerate speleogenesis and even lead to cave formation in geochemical environments that would otherwise not be conducive to dissolution. The aim of this chapter is to help the reader understand the importance of microbial activity in geochemistry and how such activity can lead to the formation and morphology of caves. The chapter then describes the role that microorganisms are known to have in speleogenesis (carbonic and sulfuric acid biospeleogenesis), hints that such activity may be occurring in newly described cave systems (iron biospeleogenesis), and a potential role in other cave systems (quartzite biospeleogenesis). It is hoped that the reader will gain an understanding of what motivates microorganisms to dramatically change their environment, understand the potential geochemical conditions where such activity could occur, and allow the informed geologist to make predictive statements as to the potential of, and for, biospeleogenesis


Occurrence of diagenetic alunites within karst cavity infill of the Dammam Formation, Ahmadi, Kuwait: an indicator of hydrocarbon gas seeps, 2014, Khalaf F. I. , Abdullah F. A.

Alunite minerals occur as white powdery lumps and laminated coloured deposits within cavity and solution channel infill of the palaeokarst zone of the Upper Eocene Dammam Formation. This formation is exposed in a quarry located on the Al Ahmadi ridge within the Greater Burgan oil field in southern Kuwait. Field occurrences and sedimentary structures of the alunite deposits were described. Collected samples were petrographically described, and their mineralogy and geochemistry were determined using X-ray diffraction and X-ray fluorescence, respectively. Microfabrics were investigated using SEM, revealing that they are primarily composed of fibrous alunogen (hydrous aluminium sulphate) and pseudo-cubical K-alunite (hydrous potassium aluminium sulphate). Their mode of occurrence suggests a hypogenetic origin, where sulphide gases associated with hydrocarbon gases reacted with an Al-rich solution leached from clay minerals and feldspars of the cavity-fill muddy sand sediments. The hydrocarbon gases may have seeped from subsurface petroliferous formations within the Greater Burgan oil field along vertical fractures. This study suggests that these acidic seeps may have played a role in the development of the palaeokarst zone of the Dammam Formation


Groundwater geochemistry observations in littoral caves of Mallorca (western Mediterranean): implications for deposition of phreatic overgrowths on speleothems., 2014, Boop L. M. , Onac B. P. , Wynn J. G. , Fornós J. J. , Rodríguezhomar M. , Merino A.

Phreatic overgrowths on speleothems (POS) precipitate at the air-water interface in the littoral caves of Mallorca, Spain. Mainly composed of calcite, aragonite POS are also observed in specific locations. To characterize the geochemical environment of the brackish upper water column, water samples and salinity values were collected from water profiles (0-2.9 m) in April 2012 and March 2013 near aragonite POS in Cova des Pas de Vallgornera and calcite POS in Coves del Drac (hereafter, Vallgornera and Drac). Degassing of CO2 from the water was evidenced by the existence of lower dissolved inorganic carbon (DIC) concentration and enriched δ13CDIC values in a thin surface layer (the uppermost 0.4 m), which was observed in both profiles from Drac. This process is facilitated by the efficient exchange of cave air with the atmosphere, creating a CO2 partial pressure (pCO2) disparity between the cave water and air, resulting in the precipitation of calcite POS as CO2 degasses from the water. The degassed upper layer was not observed in either profile from Vallgornera, suggesting that less efficient cave ventilation restricts outgassing of CO2, which also results in accumulation of CO2 in the cave atmosphere. The presence of an existing uncorroded POS horizon, as well as higher concentrations and large amplitude fluctuations of cave air pCO2, may indicate that aragonite POS deposition is currently episodic in Vallgornera. Ion concentration data from monthly water samples collected in each cave between October 2012 and March 2013 indicate higher Mg:Ca, Sr:Ca, Ba:Ca and Sr:Mg ratios in Vallgornera. Salinity alone does not appear to be a viable proxy for ions that may promote aragonite precipitation or inhibit calcite precipitation. Instead, these ions may be contributed by more intense bedrock weathering or deep groundwater flow.


Microbial communities in a coastal cave: Cova des Pas de Vallgornera (Mallorca, Western Mediterranean), 2014, Busquets A. , Fornós J. J. , Zafra F. , Lalucat J. , Merino A.

As a part of an ongoing project on the role of microbes in the biogeochemistry of Majorcan caves, the species diversity of microbial communities present in cave pools of anchialine waters in the Cova des Pas de Vallgornera (Mallorca, western Mediterranean) is investigated by a culture-dependent method. Two-hundred and forty-eight strains isolated from this characteristic cave environment of the littoral karst are identified by whole-cell-MALDI-TOF mass spectrometry and phylogeneticaly by 16S rRNA gene sequences. Total cell counts and species diversity of the bacterial communities decreas with the distance to the entrance of the cave and to the sea. Strains are mainly identified as members of the Gammaproteobacteria and Actinobacteria. Around 20% of the isolates are able to precipitate carbonates. Calcite is the predominant phase, growing in all the precipitates, although struvite is also found in one Pseudomonas and in one Aspergillus cultures. Differences in crystal characteristics of external shape (habit) and growth are observed according to the bacterial species promoting the precipitates. Bacteria associated with multicolored ferromanganese deposits, present in several parts of the cave, are also studied and are identified as Pseudomonas benzenivorans and Nocardioides luteus. The preponderance of Pseudomonas species and the possible contribution of bacteria in calcite deposition are discussed.


Genesis of folia in a non-thermal epigenic cave (Matanzas, Cuba), 2014, D’angeli Ilenia Maria, De Waele Jo, Melendres Osmany Ceballo, Tisato Nicola, Sauro Francesco, Gonzales Esteban Ruben Grau, Bernasconi Stefano M. , Torriani Stefano, Bontognali Tomaso R. R.

Folia are an unusual speleothem type resembling inverted cups or bracket fungi. The mechanism of folia formation is not fully understood and is the subject of an ongoing debate. This study focuses on an occurrence of folia present in Santa Catalina Cave, a non-thermal epigenic cave located close to Matanzas (Cuba). The sedimentology, morphology, petrology, permeability and geochemistry of these folia have been studied to gain new insight on the processes leading to their development. It is concluded that folia in Santa Catalina Cave formed at the top of a fluctuating water body, through CO2-degassing or evaporation, which may have been enhanced by the proximity to cave entrances. Two observations strongly support our conclusions. (1) When compared to other subaqueous speleothem (e.g. cave clouds) present in the same rooms, folia occur exclusively within a limited vertical interval that likely represents an ancient water level. Folia occur together with calcite rafts and tower cones that developed, respectively, on top of and below the water level. This suggests that a fluctuating interface is required for folia formation. (2) The measured permeability of the folia is too high to trap gas bubbles. Thus, in contrast to what has been proposed in other studies, trapped bubbles of CO2 cannot be invoked as the key factor determining the genesis and morphology of folia in this subaqueous environment


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