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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

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That Karstrandebene is (german.) see karst margin plain.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 atmospheric co2 (Keyword) returned 17 results for the whole karstbase:
Showing 1 to 15 of 17
A possible mechanism for growth of calcite speleothems without participation of biogenic carbon dioxide, 1982, Dreybrodt W,
Using Plummer et al.'s [11] rate equations on the dissolution and deposition of CaCO3 in H2O---CO2 systems, we have calculated deposition rates of CaCO3 to stalagmites in caves which are covered by glaciers or bare karst. In this case no biogenic CO2 from vegetated soil is available and the deposition of CaCO3 involves only atmospheric CO2. The mechanism of deposition proceeds by a temperature effect. Cold melting waters of about 0[deg]C dissolve CaCO3 under open system conditions at the surface of the rock. When this solution saturated with respect to CaCO3, flows through the limestone rock its temperature increases by several degrees. Therefore, it becomes supersaturated, and CaCO3 is deposited under open system conditions in the warmer cave. Maximal growth rates of about 10-3 cm/year are possible. From the kinetics of the deposition of CaCO3 from the thin water films present at the surface of stalagmites we are able to estimate the isotopic composition of carbon in the CaCO3 deposited on the stalagmites to be approximately [delta]13C = %, which is close to some observed values.From our data we conclude that substantial growth of stalagmites is possible during glacial periods as well as in areas of bare karst, a question which was not resolved up to now

COMPARISON OF THE C-14 ACTIVITY OF GROUNDWATER AND RECENT TUFA FROM KARST AREAS IN YUGOSLAVIA AND CZECHOSLOVAKIA, 1989, Horvatincic N. , Srdoc D. , Silar J. , Tvrdikova H. ,
C-14 activity of dissolved inorganic carbon (DIC) in water and in recent tufa samples in several karst areas of Yugoslavia and Czechoslovakia was measured. Groundwater from 11 karst springs were measured for their isotopic content (C-14, H-3, C-13), chemical composition (HCO3, Ca2, Mg2) and physico-chemical properties (temperature, pH). Seasonal variations of the C-14 activity of DIC in two karst springs in Plitvice Lakes area, Yugoslavia, were measured systematically from 1979-1987. C-14 activity of recent tufa samples from several locations downstream were also measured. The activity of DIC in karst spring water in both countries ranged from 63-87 pMC, which is attributed to differences in geologic structure of the recharge area, topsoil thickness and composition. Grouping of C-14 activities of DIC ca (824)% is evident. Tritium activity at all the springs indicated short mean residence time (1-10 yr). Concentration of HCO3, Ca2 and Mg2 in spring water varied with geomorphology. C-14 activity of streamwater and recent tufa increased downstream from karst springs due to the exchange between atmospheric CO2 and DIC

Radiocarbon concentration and origin of thermal Karst waters in the region of the Bukk Mountains, northeastern Hungary, 1995, Hertelendi E. , Veres M. , Futo I. , Svingor E. , Miko L. , Lenart L. , Deak J. , Suveges M. ,
Karst springs are abundant in Hungary, and many are thermal (temperatures >30 degrees C). As thermal springs are a significant part of Hungary's water resources, it is important to quantify their travel times in the karst systems. Thus, we chose to measure T and delta(18)O in the water and delta(13)C and C-14 in dissolved inorganic carbon (DIC) in water from 50 thermal and nonthermal springs and wells in the Bukk Mountains, northeastern Hungary, Environmental isotope data confirm the karst waterflow pattern implied by earlier studies. We found the water in warm springs and boreholes to be mixtures of cold young and old thermal water. We also determined short mean-residence times for some large cold springs. The C-14 activities measured in these springs indicate that the recharge area of the karst aquifer is open to the atmosphere, and atmospheric CO2 contributes to the C-14 activity of these groundwaters. We observed good correlation between C-14 and H-3 activities and we determined negative correlations between C-14 concentration and delta(13)C values and temperature. From the delta(18)O values of the oldest thermal waters, we attribute their origin to precipitation during colder temperatures than at present

Special speleothems in cement-grouting tunnels and their implications of the atmospheric CO2 sink, 1998, Liu Z. H. , He D. B. ,
Based on the analyses and comparisons of water chemistry, stable carbon isotopes and deposition rates of speleothems, the authors found that there are two kinds of speleothems in the tunnels at the Wujiangdu Dam site, Guizhou, China, namely the CO2-outgassing type and the CO2-absorbing type. The former is natural, as observed in general karst caves, and the product of karst processes under natural conditions. The latter, however, is special, resulting from the carbonation of a cement-grouting curtain and concrete. Due to the quick absorption of CO2 from the surrounding atmosphere, evidenced by the low CO2 content in the air and the high deposition rate of speleothems (as high as 10 cm/a) in the tunnels, the contribution of the carbonation process to the sink of CO2 in the atmosphere is important tin the order of magnitude of 10(8) tons c/a) and should be taken into consideration in the study of the global carbon cycle because of the use of cement on a worldwide scale

CO2 source-sink in karst processes in karst areas of China, 1999, Jiang Z. C. , Yuan D. X. ,
The CO2 source-sink of atmospheric greenhouse has a close relationship with karst processes. The corrosion of carbonate rocks lends to the sink of atmospheric CO2, whereas the deposition of carbonate rocks gives off CO2 into atmosphere, which is one of the sources of atmospheric CO2. According to the exposed areas of carbonate rocks in China, the flux of atmospheric CO2 consumed in karst processes is estimated at about 1.77 x 10(13) g CO2/a, Considering the global karst area the flux Of atmospheric CO2 consumed in corrosion may be an important parr of the missing sink. And the sink has a tendency of continuous increase. The release of CO2 from karst water is usually less than the sink of atmospheric CO2 consumed in karst processes. But in active tectonic zone the release of high CO2 concentration of mantle source in the geothermal karst water should not be neglected

Application of carbon isotope for discriminating sources of soil CO2 in karst area, Guizhou, 2001, Li T. Y. , Wang S. J. ,
Using carbon isotope of soil CO2 this paper discussed the sources of soil CO2 in karst area, Guizhou Province, China. Oxidation-decomposition of organic matter, respiration of plant root and activity of microbe are thought to be the major sources of soil CO2. However, in karst area, the contribution of dissolution of underlying carbonate rock to soil CO2 should be considered as in acidic environment. Atmospheric CO2 is the major composition Of Soil CO2 in surface layer of soil profiles and its proportion in Soil CO2 decreases with increase of soil depth. CO2 produced by dissolution of carbonate rock contributes 34%-46% to soil CO2 below the depth of 10cm in the studied soil profiles covered by grass

Cave air control on dripwater geochemistry, Obir Caves (Austria): Implications for speleothem deposition in dynamically ventilated caves, 2005, Spotl C. , Fairchild I. J. , Tooth A. F. ,
There are very few process studies that demonstrate the annual variation in cave environments depositing speleothems. Accordingly, we initiated a monitoring program at the Obir Caves, an Austrian dripstone cave system characterized by a seasonally changing air flow that results in a predictable pattern of high pCO(2), during summer and low pCO(2), in winter. Although similar seasonal changes in Soil pCO(2) occur, they are not directly connected with the changes in the subsurface since the dripwaters are fed from a well-mixed source showing little seasonal variation. Cold season flushing by relatively CO2-poor air enhances degassing of CO2 in the cave and leads to a high degree of supersaturation of dripwater with regard to calcite. Forced calcite deposition during the cold season also gives rise to a pronounced pattern of synchronous seasonal variations in electrical conductivity, alkalinity, pH, Ca and delta(13)C(DIC) which parallel variations recorded in delta(13)C(cave air). Chemical components unaffected by calcite precipitation (e.g., delta D,delta(18)O,SiO2,SO4) lack a seasonal signal attesting to a long residence in the karst aquifer. Modeling shows that degassing of CO2 from seepage waters results in kinetically-enhanced C isotopic fractionation, which contrasts with the equilibrium degassing shown from the Soreq cave in Israel. The Obir Caves may serve as a case example of a dripstone cave whose seepage waters (and speleothems) show intra-annual geochemical variability that is primarily due to chemical modification of the groundwater by a dynamic, bidirectional subsurface air circulation. Copyright (c) 2005 Elsevier Ltd

Sedimentary manganese metallogenesis in response to the evolution of the Earth system, 2006, Roy Supriya,
The concentration of manganese in solution and its precipitation in inorganic systems are primarily redox-controlled, guided by several Earth processes most of which were tectonically induced. The Early Archean atmosphere-hydrosphere system was extremely O2-deficient. Thus, the very high mantle heat flux producing superplumes, severe outgassing and high-temperature hydrothermal activity introduced substantial Mn2 in anoxic oceans but prevented its precipitation. During the Late Archean, centered at ca. 2.75[no-break space]Ga, the introduction of Photosystem II and decrease of the oxygen sinks led to a limited buildup of surface O2-content locally, initiating modest deposition of manganese in shallow basin-margin oxygenated niches (e.g., deposits in India and Brazil). Rapid burial of organic matter, decline of reduced gases from a progressively oxygenated mantle and a net increase in photosynthetic oxygen marked the Archean-Proterozoic transition. Concurrently, a massive drawdown of atmospheric CO2 owing to increased weathering rates on the tectonically expanded freeboard of the assembled supercontinents caused Paleoproterozoic glaciations (2.45-2.22[no-break space]Ga). The spectacular sedimentary manganese deposits (at ca. 2.4[no-break space]Ga) of Transvaal Supergroup, South Africa, were formed by oxidation of hydrothermally derived Mn2 transferred from a stratified ocean to the continental shelf by transgression. Episodes of increased burial rate of organic matter during ca. 2.4 and 2.06[no-break space]Ga are correlatable to ocean stratification and further rise of oxygen in the atmosphere. Black shale-hosted Mn carbonate deposits in the Birimian sequence (ca. 2.3-2.0[no-break space]Ga), West Africa, its equivalents in South America and those in the Francevillian sequence (ca. 2.2-2.1[no-break space]Ga), Gabon are correlatable to this period. Tectonically forced doming-up, attenuation and substantial increase in freeboard areas prompted increased silicate weathering and atmospheric CO2 drawdown causing glaciation on the Neoproterozoic Rodinia supercontinent. Tectonic rifting and mantle outgassing led to deglaciation. Dissolved Mn2 and Fe2 concentrated earlier in highly saline stagnant seawater below the ice cover were exported to shallow shelves by transgression during deglaciation. During the Sturtian glacial-interglacial event (ca. 750-700[no-break space]Ma), interstratified Mn oxide and BIF deposits of Damara sequence, Namibia, was formed. The Varangian ([identical to] Marinoan; ca. 600[no-break space]Ma) cryogenic event produced Mn oxide and BIF deposits at Urucum, Jacadigo Group, Brazil. The Datangpo interglacial sequence, South China (Liantuo-Nantuo [identical to] Varangian event) contains black shale-hosted Mn carbonate deposits. The Early Paleozoic witnessed several glacioeustatic sea level changes producing small Mn carbonate deposits of Tiantaishan (Early Cambrian) and Taojiang (Mid-Ordovician) in black shale sequences, China, and the major Mn oxide-carbonate deposits of Karadzhal-type, Central Kazakhstan (Late Devonian). The Mesozoic period of intense plate movements and volcanism produced greenhouse climate and stratified oceans. During the Early Jurassic OAE, organic-rich sediments host many Mn carbonate deposits in Europe (e.g., Urkut, Hungary) in black shale sequences. The Late Jurassic giant Mn Carbonate deposit at Molango, Mexico, was also genetically related to sea level change. Mn carbonates were always derived from Mn oxyhydroxides during early diagenesis. Large Mn oxide deposits of Cretaceous age at Groote Eylandt, Australia and Imini-Tasdremt, Morocco, were also formed during transgression-regression in greenhouse climate. The Early Oligocene giant Mn oxide-carbonate deposit of Chiatura (Georgia) and Nikopol (Ukraine) were developed in a similar situation. Thereafter, manganese sedimentation was entirely shifted to the deep seafloor and since ca. 15[no-break space]Ma B.P. was climatically controlled (glaciation-deglaciation) assisted by oxygenated polar bottom currents (AABW, NADW). The changes in climate and the sea level were mainly tectonically forced

A penultimate glacial monsoon record from Hulu Cave and two-phase glacial terminations, 2006, Cheng H, Edwards Rl, Wang Y, Kong X, Ming Y, Kelly Mj, Wang X, Gallup Cd, Liu W,
Oxygen isotope records of three stalagmites from Hulu Cave, China, extend the previous high-resolution absolute-dated Hulu Asian Monsoon record from the last to the penultimate glacial and deglacial periods. The penultimate glacial monsoon broadly follows orbitally induced insolation variations and is punctuated by at least 16 millennial-scale events. We confirm a Weak Monsoon Interval between 135.5 {} 1.0 and 129.0 {} 1.0 ka, prior to the abrupt increase in monsoon intensity at Asian Monsoon Termination II. Based on correlations with both marine ice-rafted debris and atmospheric CH4 records, we demonstrate that most of marine Termination II, the full rise in Antarctic temperature and atmospheric CO2, and much of the rise in CH4 occurred within the Weak Monsoon Interval, when the high northern latitudes were probably cold. From these relationships and similar relationships observed for Termination I, we identify a two-phase glacial termination process that was probably driven by orbital forcing in both hemispheres, affecting the atmospheric hydrological cycle, and combined with ice sheet dynamics

High resolution characterization of the Asian Monsoon between 146,000 and 99,000[no-break space]years B.P. from Dongge Cave, China and global correlation of events surrounding Termination II, 2006, Kelly Megan J. , Edwards R. Lawrence, Cheng Hai, Yuan Daoxian, Cai Yanjun, Zhang Meiliang, Lin Yushi, An Zhisheng,
Speleothem samples from Hulu (eastern China, 32[deg]30'N, 119[deg]10'E) and Dongge (southern China, 25[deg]17'N, 108[deg]5'E) Caves provide a nearly continuous record of the Asian monsoon over the last 160[no-break space]ka [Wang, Y.J., Cheng, H., Edwards, R.L., An, Z.S., Wu, J.Y., Shen, C.-C., Dorale, J.A., 2001. A high-resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave, China. Science 294, 2345-2348; Yuan, D., Cheng, H., Edwards, R.L., Dykoski, C.A., Kelly, M.J., Zhang, M., Qing, J., Lin, Y., Wang, Y., Wu, J., Dorale, J.A., An, Z., Cai, Y., 2004. Timing, duration, and transitions of the last interglacial Asian Monsoon. Science 304, 575-578]. We have obtained higher resolution data in the interval between ~ 99 and 146[no-break space]ka B.P., providing a detailed account of [delta]18O variations over most of MIS 5 and the latter portion of MIS 6. Precise 230Th dating has replicated the chronology of the samples within error. The higher resolution data set confirms the timing of Asian Monsoon Termination II (the midpoint of the negative shift in [delta]18O marking the onset of the Last Interglacial Asian Monsoon), placing it at 129.0 0.9[no-break space]ka B.P. The bulk of this transition (~ 1.7[per mille sign]) took place within approximately 70[no-break space]years, with the total range of the transition being ~ 3[per mille sign]. The most abrupt portion of the shift in [delta]18O values (~ 1.1[per mille sign]) marking the end of the Last Interglacial Asian Monsoon occurred in ~ 120[no-break space]years, the midpoint of which is 120.7 1.0[no-break space]ka B.P. The Dongge Cave monsoon [delta]18O record over late MIS 6 exhibits a series of sub-orbital millennial-scale climate shifts that average 1.3[per mille sign] in magnitude and occur on average every 1.8[no-break space]ky. Abrupt shifts in [delta]18O of up to 1[per mille sign] also occurred throughout the Last Interglacial Asian Monsoon, with periods at multi-decadal to centennial timescales. Similar to the amplitude and periodicities of events found by Dykoski et al. [Dykoski, C.A., Edwards, R.L., Cheng, H., Yuan, D., Cai, Y., Zhang, M., Lin, Y., An, Z., Revenaugh, J., 2005. A high resolution, absolute-dated Holocene and deglacial Asian monsoon record from Dongge Cave, China. Earth and Planetary Science Letters 233, 71-86.] during the Holocene in the Dongge record, these shifts cover more than 1/2 of the amplitude of millennial-scale and multi-centennial-scale interstadial events during the Last Glacial Period [Wang, Y.J., Cheng, H., Edwards, R.L., An, Z.S., Wu, J.Y., Shen, C.-C., Dorale, J.A., 2001. A high-resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave, China. Science 294, 2345-2348], and millennial-scale and multi-centennial-scale interstadial events during the Penultimate Glacial Period in China (this study). Abrupt decadal to millennial-scale climate events therefore appear to be a general feature of both glacial and interglacial climate. We demonstrate that monsoon intensity correlates well with atmospheric CH4 concentrations over the transition into the Bolling-Allerod, the Bolling-Allerod, and the Younger Dryas. In addition, we correlate an abrupt jump in CH4 concentration with Asian Monsoon Termination II. On the basis of this correlation, we conclude that the rise in atmospheric CO2, Antarctic warming, and the gradual portion of the rise in CH4 around Termination II occur within our 'Weak Monsoon Interval' (WMI), an extended interval of heavy [delta]18O between 135.5 1.0 and 129.0 1.0[no-break space]ka B.P., prior to Asian Monsoon Termination II and Northern Hemisphere warming. Antarctic warming over the millennia immediately preceding abrupt northern warming may result from the 'bipolar seesaw' mechanism. As such warming (albeit to a smaller extent) also preceded Asian Monsoon Termination I, the 'bipolar seesaw' mechanism may play a critical role in glacial terminations

An Investigation of Meromixis in Cave Pools, Lechuguilla Cave, New Mexico, 2008, Levy D. B.
Chemical characteristics of permanent stratification in cave pools (meromixis) may provide insight into the geochemical origin and evolution of cave pool waters. The objective of this study was to test the hypothesis that some pools in Lechuguilla Cave may be subject to ectogenic meromixis, where permanent chemical stratification is induced by input of relatively saline or fresh water from an external source. However, because organic C concentrations in Lechuguilla waters are low (typically < 1 mg L-1), biogenic meromixis resulting in O2(g)-depleted subsurface waters is not expected. Four pools at various depths below ground surface (0 m) were studied: (1) Lake Chandalar (-221 m), (2) Lake of the Blue Giants (LOBG) (- 277 m), (3) Lake Margaret (- 319 m), and (4) Lake of the White Roses (LOWR) (- 439 m). Water column profiles of temperature, pH, dissolved O2(g), and electrical conductivity (EC) were collected down to a maximum depth of 13.1 m using a multi-parameter sonde. Opposite pH gradients were observed at Lake Chandalar and LOBG, where pH at the surface (0.3 m) varied by 0.20 units compared to the subsurface (> 0.9 m), and are probably the result of localized and transient atmospheric CO2(g) concentrations. At LOBG, an EC increase of 93 ?S cm-1 at the 0.9-m depth suggests meromictic conditions which are ectogenic, possibly due to surface inflow of fresh water as drips or seepage into a preexisting layer of higher salinity.

An Investigation of Meromixis in Cave Pools, Lechuguilla Cave, New Mexico., 2008, Levy, D. B.

Chemical characteristics of permanent stratification in cave pools (meromixis) may provide insight into the geochemical origin and evolution of cave pool waters. The objective of this study was to test the hypothesis that some pools in Lechuguilla Cave may be subject to ectogenic meromixis, where permanent chemical stratification is induced by input of relatively saline or fresh water from an external source. However, because organic C concentrations in Lechuguilla waters are low (typically < 1 mg L-1), biogenic meromixis resulting in O2(g)-depleted subsurface waters is not expected. Four pools at various depths below ground surface (0 m)
were studied: (1) Lake Chandalar (-221 m), (2) Lake of the Blue Giants (LOBG) (- 277 m), (3) Lake Margaret (- 319 m), and (4) Lake of the White Roses (LOWR) (- 439 m). Water column profiles of temperature, pH, dissolved O2(g), and electrical conductivity (EC) were collected down to a maximum depth of 13.1 m using a multi-parameter sonde. Opposite pH gradients were observed at Lake Chandalar and LOBG, where pH at the surface (0.3 m) varied by ±0.20 units compared to the subsurface (> 0.9 m), and are probably
the result of localized and transient atmospheric CO2(g) concentrations. At LOBG, an EC increase of 93 μS cm-1 at the 0.9-m depth suggests meromictic conditions which are ectogenic, possibly due to surface inflow of fresh water as drips or seepage into a preexisting layer of higher salinity.


An Investigation of Meromixis in Cave Pools, Lechuguilla Cave, New Mexico, 2008, Levy, D. B.

Chemical characteristics of permanent stratification in cave pools (meromixis) may provide insight into the geochemical origin and evolution of cave pool waters. The objective of this study was to test the hypothesis that some pools in Lechuguilla Cave may be subject to ectogenic meromixis, where permanent chemical stratification is induced by input of relatively saline or fresh water from an external source. However, because organic C concentrations in Lechuguilla waters are low (typically < 1 mg L-1), biogenic meromixis resulting in O2(g)-depleted subsurface waters is not expected. Four pools at various depths below ground surface (0 m) were studied: (1) Lake Chandalar (-221 m), (2) Lake of the Blue Giants (LOBG) (- 277 m), (3) Lake Margaret (- 319 m), and (4) Lake of the White Roses (LOWR) (- 439 m). Water column profiles of temperature, pH, dissolved O2(g), and electrical conductivity (EC) were collected down to a maximum depth of 13.1 m using a multi-parameter sonde. Opposite pH gradients were observed at Lake Chandalar and LOBG, where pH at the surface (0.3 m) varied by ±0.20 units compared to the subsurface (> 0.9 m), and are probably the result of localized and transient atmospheric CO2(g) concentrations. At LOBG, an EC increase of 93 μS cm-1 at the 0.9-m depth suggests meromictic conditions which are ectogenic, possibly due to surface inflow of fresh water as drips or seepage into a preexisting layer of higher salinity


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.


Carbon fluxes in Karst aquifers: Sources, sinks, and the effect of storm flow, 2013, White William B.

An effective carbon loading can be calculated from measured alkalinity and pH of karst waters. The carbon loading is independent of the degree of saturation of the water and does not depend on the water being in equilibrium with the carbonate wall rock. A substantial data base of spring water analyses accumulated by students over the past 40 years has been used to probe the CO2 generation, transport, and storage in a variety of drainage basins that feed karst springs. Carbon loading in the water exiting karst drainage basins depends on the rate of CO2 generation in the soils of the catchment areas and on the partitioning between CO2 dissolved in infiltration water and CO2 lost by diffusion upward to the atmosphere. For any given drainage basin there are also influences due to vegetative cover, soil type, and the fraction of the water provided by sinking stream recharge. Losses of CO2 back to the atmosphere occur by speleothem deposition in air-filled caves, by degassing of CO2 in spring runs, and by tufa deposition in spring runs. There are seasonal cycles of CO2 generation that relate growing season and contrasts in winter/summer rates of CO2 generation. Overall, it appears that karst aquifers are a net, but leaky, sink for atmospheric CO2


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