Community news

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 solution breccia is a mass of rock composed of angular to rounded fragments of rock that have accumulated by solution of surrounding or underlying carbonate. see also collapse breccia.?

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

What is Karstbase?



Browse Speleogenesis Issues:

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;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for isotope geochemistry (Keyword) returned 13 results for the whole karstbase:
Environmental isotopes in groundwater hydrology, 1980, Fontes J.

The isotopes of hydrogen and oxygen in precipitation, 1980, Gat J. R.

Isotope geochemistry of carbonates in the weathering zone, 1980, Salomons W. , Mook W. G.

The Ladinian Calcare Rosso of the Southern Alps provides a rare opportunity to examine the temporal relationships between tepees and palaeokarst. This unit comprises peritidal strata pervasively deformed into tepees, repeatedly capped by palaeokarst surfaces mantled by terra rossa. Palaeokarsts, characterized by a regional distribution across the Southern Alps, occur at the base and at the top of the unit. Local palaeokarsts, confined to this part of the platform, occur within the Calcare Rosso and strongly affected depositional facies. Tepee deformation ranges from simple antiformal structures (peritidal tepecs) to composite breccias floating in synsedimentary cements and internal sediments (senile tepees). Peritidal tepees commonly occur at the top of one peritidal cycle, in association with subaerial exposure at the cycle top, while senile tepees affect several peritidal cycles, and are always capped by a palaeokarst surface. Cements and internal sediments form up to 80% of the total rock volume of senile tepees. The paragenesis of senile tepees is extremely complex and records several, superimposed episodes of dissolution, cement precipitation (fibrous cements, laminated crusts, mega-rays) and deposition of internal sediments (marine sediment and terra rossa). Petrographical observations and stable isotope geochemistry indicate that cements associated with senile tepees precipitated in a coastal karstic environment under frequently changing conditions, ranging from marine to meteoric, and were altered soon after precipitation in the presence of either meteoric or mixed marine/meteoric waters. Stable isotope data for the cements and the host rock show the influence of meteoric water (average deltaO-18 = - 5.8 parts per thousand), while strontium isotopes (average Sr-87/Sr-86 = 0.707891) indicate that cements were precipitated and altered in the presence of marine Triassic waters. Field relationships, sedimentological associations and paragenetic sequences document that formation of senile tepees was coeval with karsting. Senile tepees formed in a karst-dominated environment in the presence of extensive meteoric water circulation, in contrast to previous interpretations that tepees formed in arid environments, under the influence of vadose diagenesis. Tepees initiated in a peritidal setting when subaerial exposure led to the formation of sheet cracks and up-buckling of strata. This porosity acted as a later conduit for either meteoric or mixed marine/meteoric fluids, when a karst system developed in association with prolonged subaerial exposure. Relative sea level variations, inducing changes in the water table, played a key role in exposing the peritidal cycles to marine, mixed marine/meteoric and meteoric diagenetic environments leading to the formation of senile tepees. The formation and preservation in the stratigraphic record of vertically stacked senile tepees implies that they formed during an overall period of transgression, punctuated by different orders of sea level variations, which allowed formation and later freezing of the cave infills

Sulfur isotope geochemistry of Southern Appalachian mississippi valley-type deposits, 1996, Jones Henry D. , Kesler Stephen E. , Furman Francis C. , Kyle J. Richard,

Precipitation and alteration of late Cretaceous sedimentary apatites and siderites (Leonie Trough, Bavaria, Germany), 1998, Sattler C. D. , Halbach P. ,
Late Cretaceous sedimentary siderites and fluorapatites of the iron ore deposit 'Leonie' (Bavaria, Germany) have been investigated by geochemical and mineralogical methods to define their origin. The siderites consist to more than 90 mol% of FeCO3. This elemental composition relates to an early diagenetic fresh water depositional environment. The stable isotope geochemistry of carbon and oxygen (delta(18)O: parts per thousand SMOW; delta(13)C: -12 parts per thousand PDB) also supports a siderite genesis in meteoric waters, with carbon originating from oxidation of organic matter. The chemical composition of the fluorapatites is relatively pure and shows a very low elemental substitution for calcium and phosphate. This is the result of an intense epigenetic alteration of the primary carbonate fluorapatite and, thus, cannot be related to specific source aspects. Microscopic investigations and thermodynamic calculations reveal a precursory apatite precipitation before siderite was formed. This process is thought to have removed calcium from karst waters to a level which enables siderite to be precipitated. Because of the data and observations a siderite formation in a stagnant fresh water basin is postulated, while the apatite formation probably was initiated during a connection to the open ocean (Tethys) with temporary marine ingressions. The input of iron and partly of phosphorus and fluorine into the karst basins resulted from the draining of the uplifted easterly mountains of the igneous Bohemian Massif under the influence of a humid warm climate. During the postulated marine ingressions especially phosphorus and fluorine were brought into the system whereas most of the calcium and carbonate reached the karst troughs by dissolution of the Late Jurassic Maim limestones

Isotope Tracers in Catchment Hydrology., 1998, Kendall C. , Mcdonnell J. J.
This book represents a new "earth systems" approach to catchments that encompasses the physical and biogeochemical interactions that control the hydrology and biogeochemistry of the system. The text provides a comprehensive treatment of the fundamentals of catchment hydrology, principles of isotope geochemistry, and the isotope variability in the hydrologic cycle -- but the main focus of the book is on case studies in isotope hydrology and isotope geochemistry that explore the applications of isotope techniques for investigating modern environmental problems. Isotope Tracers in Catchment Hydrology is the first synthesis of physical hydrology and isotope geochemistry with catchment focus, and is a valuable reference for professionals and students alike in the fields of hydrology, hydrochemistry, and environmental science. This important interdisciplinary text provides extensive guidelines for the application of isotope techniques for all investigators facing the challenge of protecting precious water, soil, and ecological resources from the ever-increasing problems associated with population growth and environmental change, including those from urban development and agricultural land uses. More information at:

Diagenesis and porosity evolution of the Upper Silurian-lowermost Devonian West Point reef limestone, eastern Gaspe Belt, Quebec Appalachians, 2001, Bourque Pa, Savard Mm, Chi G, Dansereau P,
Diagenetic analysis based on cathodoluminescence petrography, cement stratigraphy, carbon and oxygen stable isotope geochemistry, and fluid inclusion microthermometry was used to reconstruct the porosity history and evaluate the reservoir potential of the Upper Silurian-Lower Devonian West Point limestone in the eastern part of the Gaspe Belt. The West Point limestone was investigated in two areas: 1) In the Chaleurs Bay Synclinorium, the limestone diagenesis of the lower and middle complexes of the Silurian West Point Formation was affected by repeated subaerial exposure related to late Ludlovian third-order eustatic low-stands, which coincided with the Salinic block tilting that produced the Salinic unconformity. The Anse McInnis Member (middle bank complex) underwent freshwater dissolution, and mixed marine and freshwater cementation during deposition. Concurrently, the underlying Anse a la Barbe and Gros Morbe members (lower mound and reef complex) experienced dissolution by fresh water percolating throughout the limestone succession. Despite this early development of karst porosity, subsequent meteoric-influenced cementation rapidly occluded all remaining pore space in the Gros Morbe, Anse a la Barbe, and Anse McInnis limestones. In contrast, the overlying Colline Daniel Member limestone (upper reef complex) does not show the influence of any freshwater diagenesis. Occlusion of its primary porosity occurred during progressive burial and was completed under a maximum burial depth of 1.2 kin. 2) In the Northern Outcrop Belt, the diagenesis of the Devonian pinnacle reefs of the West Point Formation followed a progressive burial trend. The primary pores of the reef limestone were not completely occluded before the reefs were buried at a significant depth (in some cases, to 6 km). Therefore, hydrocarbon migration in subsurface buildups before primary porosity occlusion might have created reservoirs. Moreover, the presence of gaseous hydrocarbons in Acadian-related veins attests to a hydrocarbon source in the area

The 'Calamine' of Southwest Sardinia: Geology, Mineralogy, and Stable Isotope Geochemistry of Supergene Zn Mineralization, 2003, Boni M, Gilg Ha, Aversa G, Balassone G,
The mining district of southwest Sardinia, Italy, is one of the classic areas where primary carbonate-hosted Zn-Pb sulfide ores are associated with a relatively thick secondary oxidation zone containing Zn (hydroxy-)carbonates and silicates, the so-called 'calamine,' exploited until the 1970s. The extent of the capping oxidized ore zones, reaching deep below the surface, is generally independent of the present-day water table. The base of the oxidation profile containing nonsulfide Zn minerals in various uplifted blocks in the Iglesiente area can be both elevated above or submerged below the recent water table. The genesis of the ores is therefore considered to be related to fossil, locally reactivated, oxidation phenomena. The mineralogy of the nonsulfide mineralization is generally complex and consists of smithsonite, hydrozincite, and hemimorphite as the main economic minerals, accompanied by iron and manganese oxy-hydroxides and residual clays. This study places the secondary ores in the context of the tectonostratigraphic and climatic evolution of Sardinia and includes a petrographic and mineralogic study of the most abundant minerals, relating the mineralogy of secondary Zn and Pb carbonates to their stable C and O isotope geochemistry and constraining the origin of the oxidizing fluids and the temperature of mineralization. The{delta} 18OVSMOW values of smithsonite are homogeneous, regardless of crystal morphology, position, and mine location (avg. 27.4 {} 0.9{per thousand}). This homogeneity points to a relatively uniform isotopic composition of the oxidation fluid and corresponding formation temperatures of 20{degrees} to 35{degrees}C. Considering the karstic environment of smithsonite formation in southwest Sardinia, this high temperature could be due to heat release during sulfide oxidation. The carbon isotope compositions of secondary Zn carbonates display considerable variations of more than 9 per mil ({delta}13CVPDB from -0.6 to -10.4{per thousand}). This large range indicates participation of variable amounts of reduced organic and marine carbonate carbon during sulfide oxidation. The isotopic variation can be related to a variation in crystal morphologies of smithsonite, reflecting different environments of formation with respect to water table oscillations in karstic environments (upper to lower vadose to epiphreatic). The same range in{delta} 13C isotope values is displayed by the calcite associated with Zn carbonates and by recent speleothems. The most reliable time span for the deposition of bulk calamine ore in southwest Sardinia ranges from middle Eocene to Plio-Pleistocene, although further multiple reactivation of the weathering profiles, peaking within the warm interglacial periods of the Quaternary, cannot be excluded

The Isotope Geochemistry and Cosmochemistry of Magnesium, 2004, Young Edward D. , Galy Albert,

Strontium isotope characterization and major ion geochemistry of karst water flow, Shentou, northern China, 2006, Wang Yanxin, Guo Qinghai, Su Chunli, Ma Teng,
SummaryKarst water is the most important source of water supply for Shanxi province, northern China. The Shentou springs are representative of the 19 major karst springs at Shanxi. The total area of the Shentou karst water system is 5316 km2, the Middle Ordovician limestone being its major karst aquifer. In this study, data about the strontium isotope geochemistry and major ion hydrochemistry were analyzed to understand the flow patterns and hydrogeochemical processes of karst water at Shentou. The contour map of TDS value of karst water and that of Sr concentration are similar, showing the general tendency of increase from the northern, western and southern boundary to the discharge area. The average values of 87Sr/86Sr ratios of karst water decrease from recharge (0.7107) to discharge area (0.7102), evolving towards those of limestone hostrocks. Comparison of 87Sr/86Sr ratios with Sr content suggests that isotopic compositions of some karst water samples from the recharge and flow through area should be the result of interaction between aquifer limestone matrix and strontium-poor recharge waters of meteoric origin. However, for samples from the discharge area that are plotted above the mixing line, mixing with groundwater in the Quaternary aquifers with high 87Sr/86Sr ratios may be another factor controlling Sr isotope chemistry. Two major groundwater flow paths were discerned from hydrogeological and geochemical data. Along both flow paths, the 87Sr/86Sr ratios of karst water show a general tendency of decrease. Geochemical modeling of the major ion geochemistry of karst water using PHREEQC also indicates that the chemistry of springs should be affected by the incorporation of groundwater in Quaternary aquifer. The effect of the mixing action on the spring hydrochemistry in flow path 1 is more remarkable than that in flow path 2, according to different mixing ratios in both paths (30% in flow path 1 and 5% in flow path 2)

Isotope geochemistry of the mafic dikes from the Vazante nonsulfide zinc deposit, Brazil, 2007, Babinski M. , Monteiro L. V. S. , Fetter A. H. , Bettencourt J. S. , Oliveir T. F.
The Vazante Group, located in the northwestern part of Minas Gerais, hosts the most important zinc mine in Brazil, the Vazante Mine, which represents a major known example of a hypogene nonsulfide zinc deposit. The main zinc ore is represented by willemite and differs substantially from other deposits of the Vazante-Paracatu region, which are sulfide-dominated zinc-lead ore. The age of the Vazante Group and the hosted mineralization is disputable. Metamorphosed mafic dikes (metabasites) that cut the metasedimentary sequence and are affected by hydrothermal processes recently were found and may shed light on the geochronology of this important geological unit. Zircon crystals recovered from the metabasites are xenocrystic grains that yield U?Pb conventional ages ranging from 2.1 to 2.4 Ga, so the basement of the Vazante Group is Paleoproterozoic or has metasedimentary rocks whose source area was Paleoproterozoic. Pb isotopes determined for titanite separated from the metabasites have common, nonradiogenic Pb compositions, which prevents determination of their crystallization age. However, the Pb signatures observed for the titanite crystals are in agreement with those determined for galena from the carbonate-hosted Zn?Pb deposits hosted by the Vazante Group, including galena from minor sulfide ore bodies of the Vazante deposit. These similarities suggest that the metalliferous fluids that affected the metabasites may have been those responsible for galena formation, which could imply a similar lead source for both nonsulfide and sulfide zinc deposits in the Vazante?Paracatu district. This common source could be related to deep-seated, basin-derived, metalliferous fluids associated with a long-lived hydrothermal system related to diagenesis and deformation of the Vazante Group during the Neoproterozoic.

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.

Results 1 to 13 of 13
You probably didn't submit anything to search for