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Enviroscan Ukrainian Institute of Speleology and Karstology


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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 seep is 1. an area, generally small, where water or oil percolates slowly to the land surface. see seepage and spring [22]. 2. to move slowly through small openings of a porous material [22].?

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


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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for oxygen (Keyword) returned 224 results for the whole karstbase:
Showing 181 to 195 of 224
Cryogenic cave carbonates from the Cold Wind Cave, Nzke Tatry Mountains, Slovakia: Extending the age range of cryogenic cave carbonate formation to the Saalian, 2009,
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k K. , Hercman H. , Orvoov M. , Jač, Kov I.

Cold Wind Cave, located at elevations ranging between 1,600 and 1,700 m a. s. l. in the main range of the NÃzke Tatry Mountains (Slovakia), is linked in origin with the adjacent Dead Bats Cave. Together, these caves form a major cave system located within a narrow tectonic slice of Triassic sediments. Both caves have undergone complex multiphase development. A system of sub-horizontal cave levels characterized by large, tunnel-like corridors was formed during the Tertiary, when elevation differences surrounding the cave were less pronounced than today. The central part of the NÃzke Tatry Mountains, together with the cave systems, was uplifted during the Neogene and Lower Pleistocene, which changed the drainage pattern of the area completely. The formation of numerous steep-sloped vadose channels and widespread cave roof frost shattering characterized cave development throughout the Quaternary. In the Cold Wind Cave, extensive accumulations of loose, morphologically variable crystal aggregates of secondary cave carbonate ranging in size between less than 1 mm to about 35 mm was found on the surface of fallen limestone blocks. Based on the C and O stable isotope compositions of the carbonate (δ13C: 0.72 to 6.34 ‰, δ18O: –22.61 to –13.68 ‰ V-PDB) and the negative relation between δ13C and δ18O, the carbonate crystal aggregates are interpreted as being cryogenic cave carbonate (CCC). Published models suggest the formation of CCC in slowly freezing water pools, probably on the surface of cave ice, most probably during transitions from stadials to interstadials. Though the formation of these carbonates is likely one of the youngest events in the sequence of formation of cave sediments of the studied caves, the 230Th/234U ages of three samples (79.7±2.3, 104.0±2.9, and 180.0±6.3 ka) are the oldest so far obtained for CCC in Central Europe. This is the first description of CCC formation in one cave during two glacial periods (Saalian and Weichselian).


OXYGEN ISOTOPES IN DIFFERENT RECESSION SUBREGIMES OF KARST SPRINGS IN THE BREZOVSK KARPATY MTS. (SLOVAKIA), 2010,
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Malk P. , Michalko J.
Karst spring hydrograph separation method based on quick iterative solution of several simple exponential and linear equations, was developed for linking small datasets of samples to various hydrologic situations. The method is based on a presumption, that a springs discharge depends on the level of aquifer saturation by groundwater, and that the same discharge reflects the same groundwater saturation (piezometric level) in the aquifer. Every spring can be described by unique sets of constant starting discharges, Q0 values, recession coefficients ? (laminar flow components in exponential equations), and ? (turbulent flow components in linear equations). Each subregime can be detected by recession curve analyses of the complete springs discharge time series. In this hydrograph separation, every measured discharge value, Qt, is then determined by a representative time, t; i.e., theoretical elapsed time t from the total maximum discharge value Qmax. The aim of the iteration process is to obtain this representative time t for each discharge. The individual flow components are calculated using the same t value. These variances in subregime discharges in a certain moment can be linked to the components analysed in the same moment, in order to obtain the end members of the theoretical mixture. This technique was developed and applied on the discharge time series of the four karstic springs in the Brezovsk Karpaty Mts. (Slovakia), built mainly by karstified Middle and Upper Triassic dolomites and limestones. Groundwater of individual springs were characterised by ?18O (SMOW) and groundwater temperature values and end members of two laminar and one turbulent subregimes were calculated. Results were based on sparsely populated datasets and manual discharge records, but represent a perspective method for future development and interpretations on limited dataset results.

Do Karst Rivers deserve their own biotic index? A ten years study on macrozoobenthos in Croatia, 2010,
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Ra?a B. , Puljas S.
In this study we present the results of a ten year survey of the aquatic macroinvertebrate fauna along four karst rivers: Jadro, rnovnica, Grab and Ruda, all of them situated in the Middle Dalmatia region of Croatia, in an attempt to construct the Iliric Biotic Index, which will be more applicable for the water quality analysis than the most frequently applied biotic index in Croatia, the Italian Modification of Extended Biotic Index. The rivers geologically belong to the Dinaric karst, unique geological phenomena in Europe. Benthic macroinvertebrates were collected along each river at 15 sites by standard methods of sampling along with several physicochemical parameters, including: temperature, dissolved oxygen, carbon dioxide, alkalinity, hardness and pH. Univariate and multivariate techniques revealed differences in the macroinvertebrate community structure as well as in physicochemical parameters between the Karst rivers and continental rivers. Based on those differences, the Iliric Biotic Index was proposed as the standard of karst river water quality in Croatia in accordance with the EU Water Framework Directive. Differences between the Iliric Biotic Index and the most commonly used biotic indices in the European Community and the USA (The Biological Monitoring Working Party (B.M.W.P.) scores, i.e. Extended Biotic Index, Indice Biotique, Family Biotic Index) suggest that karst rivers need a new biotic index.

Polyphase speleogenesis in Lick Creek Cave, Little Belt Mountains, Montana, USA, 2010,
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Carriere K. L. , Machel H. G. , Hopkins J. C.

Lick Creek Cave in northern Montana (USA) is hosted in limestones of the Lower Carboniferous Madison Group near Tiger Butte, an Eocene quartz–syenite porphyry intrusive dome. The cave is located within the zone of contact metamorphism of the dome, which crops out 300 m from the cave entrance. The cave consists of two genetically distinct cave systems separated by a fracture zone: (1) a 80 50 m dome-shaped cavern in breccias of a Carboniferous paleocave, and (2) anastomosing conduits 2–10 m across, parallel to the bedding of the Madison Group and extending 100 m up dip to the present cave entrance. The conduits are further subdivided into a tectonised and a maze zone and are variably decorated in several combinations by phreatic isopachous calcite spar cements, with crystals up to several cm long, and with vadose speleothems, including stalactite–stalagmite pairs, flowstone, corallite (cave popcorn), and moonmilk. Our database is comprised of field survey, thin section, XRD, and SEM observations along with 118 ?18O/?13C analyses and 27 87Sr/86Sr measurements from samples of county rock and speleothems. The limestone matrix samples with the heaviest ?18O/?13C ratios are interpreted as the least recrystallised proxy to Tournaisian seawater. Stable isotope data from other Carboniferous limestones, including paleocave breccias, follow a regional meteoric pathway established elsewhere in the Madison for the Late Carboniferous transition from greenhouse to icehouse conditions. Isopachous calcite spar cements from the conduit zone are interpreted as the result of late-stage, Eocene hydrothermal fluid circulation. Stalactite–stalagmite pairs, flowstone, corallite, and moonmilk carry a signature similar to modern or Quaternary high-alpine meteoric water. Previous workers have determined separate hydrothermal and meteoric ?18O/?13C stable isotope fields for speleothems in caves in Carboniferous limestones from the Black Hills, South Dakota. We re-define the stable isotope ranges for meteoric and magmatic–hydrothermal calcites based on a comparison of stable isotope data from the Little Belt Mountains with those from the Black Hills. We further propose that the hydrothermal calcite end-member ?18O composition is around ?20‰ PDB, represented by the lowest oxygen isotope values from all data sets, with a corresponding ?13C of about ?7‰ PDB. Sr-isotope data from speleothems, Carboniferous limestone wall rocks, and from the igneous intrusion itself support the interpretation of an Eocene hydrothermal speleogenic event. The integration of petrographic and geochemical data shows that Lick Creek Cave is the result of polyphase speleogenesis in three major episodes: (1) Middle to Late Carboniferous, (2) Eocene, and (3) (sub-)Recent to Recent. The Carboniferous and (sub-)Recent to Recent speleogenesis appear epigenic, i.e., driven by surface-derived waters, whereas the Eocene event was hypogenic, i.e., driven by ascending hydrothermal waters. Each of the three major speleogenic events probably consisted of two or more distinct “phases”, but our database does not permit these phases to be resolved with certainty.


Community Structure of Subsurface Biofilms in the Thermal Sulfidic Caves of Acquasanta Terme, Italy, 2010,
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Jones D. S. , Tobler D. J. , Schaperdoth I. , Mainiero M. , Macalady J. L.

We performed a microbial community analysis of biofilms inhabiting thermal (35 to 50°C) waters more than 60m below the ground surface near Acquasanta Terme, Italy. The groundwater hosting the biofilms has 400 to 830 mkM sulfide, <10 mkM O2, pH of 6.3 to 6.7, and specific conductivity of 8,500 to 10,500 mkS/cm. Based on the results of 16S rRNA gene cloning and fluorescent in situ hybridization (FISH), the biofilms have low species richness, and lithoautotrophic (or possibly mixotrophic) Gamma- and Epsilonproteobacteria are the principle biofilm architects. Deltaproteobacteria sequences retrieved from the biofilms have <90% 16S rRNA similarity to their closest relatives in public databases and may represent novel sulfate-reducing bacteria. The Acquasanta biofilms share few species in common with Frasassi cave biofilms (13°C, 80 km distant) but have a similar community structure, with representatives in the same major clades. The ecological success of Sulfurovumales-group Epsilonproteobacteria in the Acquasanta biofilms is consistent with previous observations of their dominance in sulfidic cave waters with turbulent water flow and high dissolved sulfide/oxygen ratios.


Do Karst Rivers deserve their own biotic index? A ten years study on macrozoobenthos in Croatia, 2010,
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Rađ, A B. , Puljas S.

In this study we present the results of a ten year survey of the aquatic macroinvertebrate fauna along four karst rivers: Jadro, rnovnica, Grab and Ruda, all of them situated in the Middle Dalmatia region of Croatia, in an attempt to construct the Iliric Biotic Index, which will be more applicable for the water quality analysis than the most frequently applied biotic index in Croatia, the Italian Modification of Extended Biotic Index. The rivers geologically belong to the Dinaric karst, unique geological phenomena in Europe. Benthic macroinvertebrates were collected along each river at 15 sites by standard methods of sampling along with several physicochemical parameters, including: temperature, dissolved oxygen, carbon dioxide, alkalinity, hardness and pH. Univariate and multivariate techniques revealed differences in the macroinvertebrate community structure as well as in physicochemical parameters between the Karst rivers and continental rivers. Based on those differences, the Iliric Biotic Index was proposed as the standard of karst river water quality in Croatia in accordance with the EU Water Framework Directive. Differences between the Iliric Biotic Index and the most commonly used biotic indices in the European Community and the USA (The Biological Monitoring Working Party (B.M.W.P.) scores, i.e. Extended Biotic Index, Indice Biotique, Family Biotic Index) suggest that karst rivers need a new biotic index.


Empirical equations for the temperature dependence of calcite-water oxygen isotope fractionation from 10 to 708C, 2010,
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Demeґny A. , Kele S. , Sikloґsy Z.

Although the temperature dependence of calcite-water oxygen isotope fractionation seems to have been well established by numerous empirical, experimental and theoretical studies, it is still being discussed, especially due to the demand for increased accuracy of paleotemperature calculations. Experimentally determined equations are available and have been verified by theoretical calculations (considered as representative of isotopic equilibrium); however, many natural formations do not seem to follow these relationships implying either that existing fractionation equations should be revised, or that carbonate deposits are seriously affected by kinetic and solution chemistry effects, or late-stage alterations. In order to test if existing fractionation-temperature relationships can be used for natural deposits, we have studied calcite formations precipitated in various environments by means of stable isotope mass spectrometry: travertines (freshwater limestones) precipitating from hot and warm waters in open-air or quasi-closed environments, as well as cave deposits formed in closed systems. Physical and chemical parameters as well as oxygen isotope composition of water were monitored for all the investigated sites. Measuring precipitation temperatures along with oxygen isotope compositions of waters and calcites yielded empirical environment-specific fractionation– temperature equations: [1] 1000 _ lnaј17599/T – 29.64 [for travertines with a temperature range of 30 to 70-C] and [2] 1000 _ lnaј17500/T – 29.89 [for cave deposits for the range 10 to 25-C]. Finally, based on the comparison of literature data and our results, the use of distinct calcite-water oxygen isotopic fractionation relationships and application strategies to obtain the most reliable paleoclimate information are evaluated.


Isotopic indications of water-rock interaction in the hypogene Tavrskaya cave, Crimea, Ukraine, 2011,
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Dublyansky Yuri, Klimchouk Alexander, Timokhina Elisaveta, Spö, Tl Christoph

The Inner Range of the Crimea Mountains has recently been identified as an area of previously unrecognized hypogene speleogenesis (Klimchouk et al. 2009). The entrance of the Tavrskaya cave is located in the middle of the 25 m-high scarp of the cuesta built up of Paleocene limestone. The cave comprises two parallel major passages (ca. 180 m long, up to 7-8 m high and up to 5-6 m wide) connected by a smaller passage. The major passages are slightly inclined toward the north-west following the dip of bedding. The morphology of the cave bears strong indications of dissolution at conditions of ascending flow in a confined aquifer setting.
A massive calcite crust, studied in this paper, was first found in a small cave located ca. 200 m from Tavrskaya cave along the cuesta scarp. According to its position and morphology, the cave corresponds to the rift-like “feeder” zone of Tavrskaya cave. Recently, similar calcite crust was found in Tavrskaya cave, in a rift-like passage of the  near-scarp zone. The crust is built up of a brownish translucent calcite whose columnar crystals (bounded by competitive growth surfaces) are arranged in a characteristic radiating pattern. Calcite contains only all-liquid inclusions indicating deposition at less than ca. 50ºC. It also contains filamentous biological material (possibly fungi or cyanobacteria), which sometimes facilitated entrapment of fluid inclusions. This calcite body is tentatively
interpreted as a paleo-spring deposit (ascending flow). In order to characterize the isotopic properties of this calcite and the bedrock limestone we drilled small-diameter cores through the calcite formation, as well as through the wall of a cavity devoid of calcite. Stable isotope analyses were performed along these cores. To provide a basis for comparison several samples from the same lithostratigraphic units were collected far from the cave. Along a 15 cm-long profile, both oxygen and carbon isotopes of the limestone remain stable at 18O = -4.3 0.2
h and 13C = -1.7 0.3 h (1). Only within the 1.5 cm-thick zone immediately underlying the calcite 18O and 13C values plunge to ca. -8 h and -9 h respectively,. It appears from this data that water rock-interaction associated with the deposition of this calcite produced only a thin alteration halo in the limestone. However, when data from the cave-wall cores are compared with those collected far from the cave, it appears that the “constant” values from cave walls are shifted relative to the presumably unaltered limestone values toward lower values by
ca. 1.5-3.0 h (oxygen) and 3-4 h (carbon). On the 18O-13C cross-plot the data for unaltered limestone, cave wall limestone, alteration halo, and secondary calcite plot along a well-defined line (R2=0.99).
We propose that the Paleocene limestone in the vicinity of the Tavrskaya cave has experienced a two-stage alteration. During the first stage, presumably associated with the process of cave excavation, the bedrock has been altered (18O depleted by 1.5 to 3.0 h and 13C by 3 to 4 %). The thickness of this zone of early alteration is unknown but must be larger than 15 cm (length of our cores). The second stage of alteration was associated with the deposition of calcite; during this stage the isotopic composition was further depleted (by 4-5 h in 18O and 8-10 h in 13C). The extent of alteration was much smaller, though, and restricted to zones where calcite was deposited (ca. 15 mm beneath the calcite).


Pleistocene water intrusions from the Mediterranean and Caspian seas into the Black Sea, 2011,
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Badertscher S. , Fleitmann D. , Cheng H. , Edwards R. L. , Gö, Ktü, Rk O. M. , Zumbü, Hl A. , Leuenberger M. , Tü, Ysü, Z O.

The hydrological balance of the Black Sea is governed by riverine input and by the exchange with the Mediterranean Sea through the shallow Bosporus Strait. These sources have distinctly different oxygen isotope (δ18O) signatures. Therefore, the δ18O of Black Sea water directly reflects the presence or absence of a connection with the Mediterranean Sea, as well as hydrological changes in the vast watersheds of the Black and Caspian seas1, 2, 3. However, the timing of late to middle Pleistocene water intrusions to the Black Sea is poorly constrained in sedimentary sequences4, 5. Here we present a stacked speleothem δ18O record from Sofular Cave in northern Turkey that tracks the isotopic signature of Black Sea surface water, and thus allows a reconstruction of the precise timing of hydrological shifts of the Black Sea. Our record, which extends discontinuously over the last 670,000 years, suggests that the connection between the Black Sea and Mediterranean Sea has been open for a significant period at least twelve times since 670,000 yr ago, more often than previously suggested4, 5. Distinct minima in the Sofular δ18O record indicate at least seven intervals when isotopically depleted freshwater from the Caspian Sea entered the Black Sea. Our data provide precisely dated evidence for a highly dynamic hydrological history of the Black Sea.


Eolianites and Karst Development in the Mayan Riviera, Mexico, 2011,
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Kelley Kristin N. , Mylroie John E. , Mylroie Joan R. , Moore Christopher M. , Collins Laura R. , Ersek Lica, Lascu Ioan, Roth Monica J. , Moore Paul J. , Passion Rex, Shaw Charles

Coastal Quintana Roo, Mexico, including islands such as Cozumel and Isla Mujeres, contains numerous ridges of Quaternary eolian calcarenite in two packages, one Pleistocene and one Holocene. The Pleistocene eolianites are recognizable in the field by well-developed terra rossa paleosol and micritic crust on the surface, containing a fossil epikarst. The foreset beds of these eolianites commonly dip below modern sea level, and fossilized plant root structures are abundant. The Holocene
eolianites lack a well-developed epikarst, and have a calcernite protosol on their surfaces. The degree of cementation, and the grain composition, are not reliable indicators of the age of Quaternary eolianites.

The Pleistocene eolianites have been previously described (e.g. Ward, 1997) as exclusively regressive-phase eolianites, formed by the regression during the oxygen isotope substages (OIS) 5a and 5c. However, certain eolianites, such as those at Playa Copal, contain flank margin caves, dissolution chambers that form by sea water/fresh water mixing in the fresh-water lens. For such mixing dissolution to occur, the eolianite must already be present. As the flank margin caves are found at elevations of 2-6 m above current sea level, the caves must have developed during the last interglacial sea-level highstand, and the eolianites could not have formed on the regression from that or younger highstands. Therefore the eolianites must be transgressive-phase
eolianites developed at the beginning of the last interglacial sea-level highstand, or either transgressive- or regressive-phase eolianites from a previous sea-level highstand that occurred earlier in the Pleistocene. There is no field evidence of oxygen isotope substage 5c or 5a eolianites as suggested by Ward (1997).

Most coastal outcrops show classic regressive–phase Pleistocene eolianites as illustrated by complex and well-developed terra rossa paleosols and epikarst, and dense arrays of fossilized plant roots. However, in addition to flank margin caves, other evidence of transgressive-phase eolianites includes notches in eolianites on the west side of Cozumel, with subtidal marine facies onlapping the notches. The absence of a paleosol between those two units indicates that the eolianite is a transgressive-phase deposit from the last interglacial. All Holocene eolianites are, by definition, transgressive-phase units.


Tracing the sources of cave sulfates: a unique case from Cerna Valley, Romania, 2011,
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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.


LETTER: Comments on processes contributing to the isotope composition of 13C and 18O in calcite deposited to speleothems , 2011,
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Dreybrod, Wolfgang

Isotope compositions of carbon and oxygen in calcite de­posited to stalagmites are regarded as important proxies for paleo-climate. The number of papers reporting such proxies rises rapidly. Additionally cave monitoring is be­ing performed to observe chemical properties of the wa­ter dripping to speleothems, the partial pressure of CO2 in the soil above the cave and in the cave atmosphere, and other parameters outside the cave to relate recent climate conditions to recently deposited calcite.

There are, however, physical and chemical processes independent of climatic conditions, which also contrib­ute to the isotope composition and which can add noise to the climate signal. In this letter I resume these from the current literature to open a more easy access to this problem than available from the current original publi­cations.


NALPS: a precisely dated European climate record 12060 ka, 2011,
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Boch R. Cheng H. , Spotl C. , Edwards R. L. , Wang X. , Hauselmann Ph.

Accurate and precise chronologies are essential in understanding the rapid and recurrent climate variations of the Last Glacial – known as Dansgaard-Oeschger (D-O) events – found in the Greenland ice cores and other climate archives. The existing chronological uncertainties during the Last Glacial, however, are still large. Radiometric age data and stable isotopic signals from speleothems are promising to improve the absolute chronology. We present a record of several precisely dated stalagmites from caves located at the northern rim of the Alps (NALPS), a region that favours comparison with the climate in Greenland. The record covers most of the interval from 120 to 60 ka at an average temporal resolution of 2 to 22 yr and 2_-age uncertainties of ca. 200 to 500 yr. The rapid and large oxygen isotope shifts of 1 to 4.5‰ occurred within decades to centuries and strongly mimic the Greenland D-O pattern. Compared to the updated Greenland ice-core timescale (GICC05modelext) the NALPS record confirms the timing of rapid warming and cooling transitions between 118 and 106 ka, but suggests younger ages for D-O events between 106 and 60 ka. As an exception, the timing of the rapid transitions into and out of the stadial following GI 22 is earlier in NALPS than in the Greenland ice-core timescale. In addition, there is a discrepancy in the duration of this stadial between the icecore and the stalagmite chronology (ca. 2900 vs. 3650 yr). The short-lived D-O events 18 and 18.1 are not recorded in NALPS, provoking questions with regard to the nature and the regional expression of these events. NALPS resolves recurrent short-lived climate changes within the cold Greenland stadial and warm interstadial successions, i.e. abrupt warming events preceding GI 21 and 23 (precursor-type events) and at the end of GI 21 and 25 (rebound-type events), as well as intermittent cooling events during GI 22 and 24. Such superimposed events have not yet been documented outside Greenland. 


NALPS: a precisely dated European climate record 12060 ka, 2011,
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Boch R. , Cheng H. , Spotl C. , Edwards R. L. , Wang X. , Hauselmann Ph.

Accurate and precise chronologies are essential in understanding the rapid and recurrent climate variations of the Last Glacial – known as Dansgaard-Oeschger (D-O) events – found in the Greenland ice cores and other climate archives. The existing chronological uncertainties during the Last Glacial, however, are still large. Radiometric age data and stable isotopic signals from speleothems are promising to improve the absolute chronology. We present a record of several precisely dated stalagmites from caves located at the northern rim of the Alps (NALPS), a region that favours comparison with the climate in Greenland. The record covers most of the interval from 120 to 60 ka at an average temporal resolution of 2 to 22 yr and 2_-age uncertainties of ca. 200 to 500 yr. The rapid and large oxygen isotope shifts of 1 to 4.5‰ occurred within decades to centuries and strongly mimic the Greenland D-O pattern. Compared to the updated Greenland ice-core timescale (GICC05modelext) the NALPS record confirms the timing of rapid warming and cooling transitions between 118 and 106 ka, but suggests younger ages for D-O events between 106 and 60 ka. As an exception, the timing of the rapid transitions into and out of the stadial following GI 22 is earlier in NALPS than in the Greenland ice-core timescale. In addition, there is a discrepancy in the duration of this stadial between the icecore and the stalagmite chronology (ca. 2900 vs. 3650 yr). The short-lived D-O events 18 and 18.1 are not recorded in NALPS, provoking questions with regard to the nature and the regional expression of these events. NALPS resolves recurrent short-lived climate changes within the cold Greenland stadial and warm interstadial successions, i.e. abrupt warming events preceding GI 21 and 23 (precursor-type events) and at the end of GI 21 and 25 (rebound-type events), as well as intermittent cooling events during GI 22 and 24. Such superimposed events have not yet been documented outside Greenland.

 


Isotopic composition of atmospheric precipitation and karstic springs of the north-west slope of the Crimean Mountains, 2011,
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Dublyansky Y. V. , Klimchouk . B. , Amelichev G. N. , Tokarev S. V. , Sptl C.

Atmospheric precipitation was sampled for isotopic analyses according to GNIP protocol at two stations in Crimea,  Ukraine: Simferopol (24 months) and Chatyrdag (15 months). In addition, several karstic springs and one well tapping deep karstic  aquifer were sampled. The δD vs. δ 18 O relationship is only slightly differs from global Meteoric Water Line. Variable degrees of  correlation with the air temperature and the precipitation amount suggest that the isotopic composition of precipitation is affected  by several processes (e.g., air temperature and supply of moisture from different sources). Interestingly, drastically different make-ups of precipitation were observed simultaneously at two stations located only 23 km apart.  Waters in seven karstic springs discharging at Dolgorukovsky massif (2), Chatirdag (1), Baidarsky basin (3), and Mangup-kale  (1) have isotopic compositions that follow local meteoric water line but are lighter than weighted annual mean values for their  respective catchment areas. Isotopic composition of the underground stream in Krasnaya (Red) cave is nearly constant and thus,  decoupled from changes in both the isotopic composition of atmospheric precipitation in the recharge area and the flow regime  (flood or base flow). This suggests a strong buffering and homogenizing role of the soil cover and the epikarst zone, as well as  the predominant role of winter recharge on these karst massifs. Still lighter isotopic composition of deep karstic water tapped by  a borehole is tentatively explained by old, pre-Holocene age of this water.


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