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Speleology in Kazakhstan

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

New publications on hypogene speleogenesis

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

The deepest terrestrial animal

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

Caves - landscapes without light

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

Did you know?

That stress, seepage is when water flows through a porous medium, force is transferred from the water to the medium by viscous friction. the force transferred to the medium is equal to the loss of hydraulic head. this force, called seepage force, is exerted in the direction of flow [21].?

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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 molar (Keyword) returned 13 results for the whole karstbase:
The kinetics of the reaction CO2?>H? as one of the rate limiting steps for the dissolution of calcite in the system H2O-CO2-CaCO3, 1996, Dreybrodt W, Lauckner J, Liu Zh, Svensson U, Buhmann D,
Dissolution of CaCO3 in the system H2O-CO2-CaCO3 is controlled by three rate-determining processes: The kinetics of dissolution at the mineral surface, mass transport by diffusion, and the slow kinetics of the reaction H2O CO2 = H HCO3-. A theoretical model of Buhmann and Dreybrodt (1985a,b) predicts that the dissolution rates depend critically on the ratio V/A of the volume V of the solution and the surface area A of the reacting mineral. Experimental data verifying these predictions for stagnant solutions have been already obtained in the range 0.01 cm < V/A < 0.1 cm. We have performed measurements of dissolution rates in a porous medium of sized CaCO3 particles for V/A in the range of 2 . 10(-4) cm and 0.01 cm in a system closed with respect to CO2 using solutions pre-equilibrated with an initial partial pressure of CO2 of 1 . 10(-2) and 5 . 10(-2) atm. The results are in satisfactory agreement with the theoretical predictions and show that especially for V/A < 10(-3) cm dissolution is controlled entirely by conversion of CO2 into H and HCO3-, whereas in the range from 10(-3) cm up to 10(-1) cm both CO2-conversion and molecular diffusion are the rate controlling processes. This is corroborated by performing dissolution experiments using 0.6 mu molar solutions of carbonic anhydrase, an enzyme enhancing the CO2-conversion rates by several orders of magnitude. In these experiments CO2 conversion is no longer rate limiting and consequently the dissolution rates of CaCO3 increase significantly. We have also performed batch experiments at various initial pressures of CO2 by stirring sized calcite particles in a solution with V/A = 0.6 cm and V/A = 0.038 cm. These data also clearly show the influence of CO2-conversion on the dissolution rates. In all experiments inhibition of dissolution occurs close to equilibrium. Therefore, the theoretical predictions are valid for concentrations c less than or equal to 0.9 c(eq). Summarising we find good agreement between experimental and theoretically predicted dissolution rates. Therefore, the theoretical model can be used with confidence to find reliable dissolution rates from the chemical composition of a solution for a wide field of geological applications

Dedolomitization as a driving mechanism for karst generation in Permian Blaine formation, southwestern Oklahoma, USA, 1997, Raines M. A. , Dewers T. A. ,
Cyclic deposits of Permian shales, dolomites, and halite and gypsum-bearing strata in the Blaine Formation of Southwestern Oklahoma contain abundant karst features. The present study shows that an important mechanism of karst development in these sequences is dedolomitization, wherein gypsum and dolomite in close spatial proximity dissolve and supersaturate groundwaters with respect to calcite. The net loss of mass accompanying this process (dolomite and gypsum dissolution minus calcite precipitation) can be manifest in secondary porosity development while the coupled nature of this set of reactions results in the retention of undersaturated conditions of groundwater with respect to gypsum. The continued disequilibrium generates karst voids in gypsum-bearing aquifers, a mineral-water system that would otherwise rapidly equilibrate. Geochemical modeling (using the code PHRQPITZ, Plummer et al 1988) of groundwater chemical data from Southwestern Oklahoma from the 1950's up to the present suggests that dedolomitization has occurred throughout this time period in evaporite sequences in Southwestern Oklahoma. Reports from groundwater well logs in the region of vein calcite suggest secondary precipitation, an observation in accord with dedolomite formation In terms of the amounts of void space produced by dissolution, dedolomitization can dominate gypsum dissolution alone, especially in periods of quiescent aquifer recharge when gypsum-water systems would have otherwise equilibrated and karst development ceased. Mass balance modeling plus molar volume considerations show that for every cubic cm of original rock (dolomite plus gypsum), there is 0.54 cm(3) of calcite and 0.47 cm(3) of void space produced Only slightly more pore space results if the dedolomitization reaction proceeds by psuedomorphic replacement of dolomite by calcite than in a reaction mechanism based on conservation of bicarbonate

Late Pleistocene microtine rodents from Snake Creek Burial Cave, White Pine County, Nevada, 1998, Bell Cj, Mead Ji,
A total of 395 microtine rodent specimens recovered from Snake Creek Burial Cave (SCBC) are referred to Microtus SP. and Lemmiscus curtatus. Radiocarbon and Uranium series dates indicate an ae for these fossils of between 9460 160) yr. B.P. and 15,1000 700 yr, B.P. The sample of lower first molars of Lemmiscus includes 4-, 5-, and B-closed triangle morphotypes. Earlier reports of the 4-closed triangle morphotype are from Irvingtonian deposits in Colorado, Nevada, and New Mexico and from early Rancholabrean deposits in Washington. The morphotype is not known in living populations of Lemmiscus. SCBC specimens constitute the youngest record of the 4-closed triangle morphotype and are the only-specimens reported item the late Rancholabrean. Thc time of disappearance of Lemmiscus with this molar morphology is unknown, but populations with this morphotype possibly became extinct at or near the end of the Pleistocene

Hydrochemical Interpretation of Cave Patterns in the Guadalupe Mountains, New Mexico, 2000, Palmer, A. N. , Palmer, M. V.
Most caves in the Guadalupe Mountains have ramifying patterns consisting of large rooms with narrow rifts extending downward, and with successive outlet passages arranged in crude levels. They were formed by sulfuric acid from the oxidation of hydrogen sulfide, a process that is now dormant. Episodic escape of H2S-rich water from the adjacent Delaware Basin, and perhaps also from strata beneath the Guadalupes, followed different routes at different times. For this reason, major rooms and passages correlate poorly between caves, and within large individual caves. The largest cave volumes formed where H2S emerged at the contemporary water table, where oxidation was most rapid. Steeply ascending passages formed where oxygenated meteoric water converged with deep-seated H2S-rich water at depths as much as 200 m below the water table. Spongework and network mazes were formed by highly aggressive water in mixing zones, and they commonly rim, underlie, or connect rooms. Transport of H2S in aqueous solution was the main mode of H2S influx. Neither upwelling of gas bubbles nor molecular diffusion appears to have played a major role in cave development, although some H2S could have been carried by less-soluble methane bubbles. Most cave origin was phreatic, although subaerial dissolution and gypsum-replacement of carbonate rock in acidic water films and drips account for considerable cave enlargement above the water table. Estimates of enlargement rates are complicated by gypsum replacement of carbonate rock because the gypsum continues to be dissolved by fresh vadose water long after the major carbonate dissolution has ceased. Volume-for-volume replacement of calcite by gypsum can take place at the moderate pH values typical of phreatic water in carbonates, preserving the original bedrock textures. At pHs less than about 6.4, this replacement usually takes place on a molar basis, with an approximately two-fold volume increase, forming blistered crusts.

Mineral replacement reactions: from macroscopic observations to microscopic mechanisms, 2002, Putnis, A.

Mineral replacement reactions take place primarily by dissolution-reprecipitation processes. Processes such as cation exchange, chemical weathering, deuteric alteration, leaching, pseudomorphism, metasomatism, diagenesis and metamorphism are all linked by common features in which one mineral or mineral assemblage is replaced by a more stable assemblage. The aim of this paper is to review some of these aspects of mineral replacement and to demonstrate the textural features they have in common, in order to emphasize the similarities in the underlying microscopic mechanisms. The role of volume change and evolution of porosity is explored both from natural microtextures and new experiments on model replacement reactions in simple salts. It is shown that the development of porosity is often a consequence of mineral replacement processes, irrespective of the relative molar volumes of parent and product solid phases. The key issue is the relative solubility of the phases in the fluid phase. Concepts such as coupled dissolution-precipitation, and autocatalysis are important in understanding these processes. Some consequences of porosity generation for metamorphic fluid flow as well as subsequent crystal growth are also discussed.

Cyclic sequences, events and evolution of the Sino-Korean plate, with a discussion on the evolution of molar-tooth carbonates, phosphorites and source rocks, 2003, Meng X. H. , Ge M. ,
This paper gives an account of the research that the authors conducted on the cyclic sequences, events and evolutionary history from Proterozoic to Meso-Cenozoic in the Sino-Korean plate based on the principle of the Cosmos-Earth System. The authors divided this plate into 20 super-cyclic or super-mega-cyclic periods and more than 100 Oort periods. The research focused on important sea flooding events, uplift interruption events, tilting movement events, molar-tooth carbonate events, thermal events, polarity reversal events, karst events, volcanic explosion events and storm events, as well as types of resource areas and paleotectonic evolution. By means of the isochronous theory of the Cosmos-Earth System periodicity and based on long-excentricity and periodicity, the authors elaborately studied the paleogeographic evolution of the aulacogen of the Sino-Korean plate, the oolitic beach platform formation, the development of foreland basin and continental rift valley basin, and reconstructed the evolution of tectonic paleogeography and stratigraphic framework in the Sino-Korean plate in terms of evolutionary maps. Finally; the authors gave a profound discussion on the formation and development of molar-tooth carbonates, phosphorites and source rocks

A possible heptaxodontine and other caviidan rodents from the quaternary of Jamaica, 2003, Macphee R. D. E. , Flemming C. ,
New World hystricognath rodents (parvorder Caviida) easily qualify as the most diversified members of the nonvolant Quaternary land mammal fauna of the West Indies. This paper describes three intriguing but problematic representatives of this group from Jamaican cave deposits. The first is the holotype (and still the only) specimen of Alterodon major from Wallingford Roadside Cave, a taxon that continues to generate controversy because specialists disagree as to its placement within Caviida. We reject the argument that it should be placed in Octodontidae and reaffirm the high probability that it is a clidomyine. The second fossil is a large proximal femur, apparently recovered from Sheep Pen locality near Windsor (Trelawney Parish) in the 1960s. Much larger than the femur of Clidomys (previously thought to be Jamaica's largest Quaternary mammal), in size and morphology the new fossil somewhat resembles femora of the eastern Caribbean heptaxodontine Amblyrhiza. Although firm allocation is not possible, the Sheep Pen femur is possibly that of a megafaunal caviidan. The third fossil described in this paper is the jaw of a previously unknown caviidan from a dated end-Pleistocene cave context in Portland Ridge (Jackson's Bay, Clarendon Parish). Xaymaca fulvopulvis, new genus and species, differs from all West Indian caviidan species presently known. The jaw is well preserved but retains only the incisor and premolar (the latter in a very worn state). The few features for which the new species can be usefully analyzed and compared to caviidan groups represented in the West Indian Cenozoic (capromyids, heteropsornyines, heptaxodontines, and clidomyines) are largely indecisive from a systematic perspective. However, on balance the strongest indicators seem to lie with the 'giant' heptaxodontines of the central and eastern Caribbean (the grouping composed of Amblyrhiza, Elasmodontomys, and possibly Quemisia), and despite its diminutive size Xaymaca is tentatively placed within that group. It is increasingly apparent that much still remains to be learned about the origin and history of the land mammal fauna of Jamaica

Carbonate-Hosted Zn-Pb Deposits in Upper Silesia, Poland: Origin and Evolution of Mineralizing Fluids and Constraints on Genetic Models, 2003, Heijlen Wouter, Muchez Philippe, Banks David A. , Schneider Jens, Kucha Henryk, Keppens Eddy,
Microthermometric and crush-leach analyses of fluid inclusions in ore and gangue minerals of the Upper Silesian Zn-Pb deposits, Poland, along with first results of Rb-Sr geochronology on sulfides, provide important constraints on the paleohydrogeologic and metallogenetic models for the origin of these ores. The analyzed samples comprise two generations of dolomite, two generations of sphalerite, galena, and late calcite. The two dolomite generations and the late calcite were also analyzed for their oxygen and carbon isotope compositions, allowing a characterization of the mineralizing fluids. The ore-forming fluids represent highly saline (20-23 wt % CaCl2 equiv) Na-Ca-Cl brines, episodically introduced into the Triassic host carbonates. They had an oxygen isotope composition of ~0 per mil V-SMOW. Their Na-Cl-Br content (molar Na/Br and Cl/Br ratios between 99 and 337 and between 248 and 560, respectively) suggests that they originated by evaporation of seawater, which most likely occurred in the Permian-Triassic. The relative concentrations of potassium (molar K/Cl between 0.0147 and 0.0746) and lithium (molar Li/Cl between 0.0004 and 0.0031) further indicate that the fluids significantly interacted with siliciclastic rocks. The ionic and calculated oxygen isotope compositions of the fluids indicate that they were more evolved than present-day brines in the Upper Silesian coal basin, and the present-day brines show more extensive mixing with low-salinity fluids. The first results of direct Rb-Sr dating of ore-stage sulfides yield an isochron model age of 135 {} 4 Ma for the mineralizing event. This is consistent with hydrothermal activity and ore formation in Upper Silesia occurring in response to Early Cretaceous crustal extension preceding the opening of the northern Atlantic Ocean. The data presented support a model in which bittern brines migrated down into the deep subsurface and evolved into mineralizing fluids owing to extensive water-rock interaction. They were episodically expelled along deeply penetrating faults during the Early Cretaceous to form Zn-Pb deposits in the overlying Mesozoic carbonate rocks

The Pleistocene Ma U’Oi cave, northern Vietnam: palaeontology, sedimentology and palaeoenvironments, 2004, Bacon Am, Demeter F, Schuster M, Long Vt, Thuy Nk, Antoine Po, Sen S, Nga Hh, Huong Nm,
In November 2001, a Vietnamese-French team undertook the excavation of the Ma U’Oi cave in northern Vietnam. This limestone karst cave is located in the province of Hoa Binh, 70 km ESE from Hanoi and is typical of the northern Vietnam landscape. The site yielded an in situ mammalian fauna of a relatively modern composition. We also found a mixed fauna with a lower molar attributed to an archaic Homo (Demeter et al., in press). We estimate the age of Ma U’Oi fauna between 169 kyr, the age of Thum Wiman Nakin (Esposito et al., 1998) estimated by U/Th method and 80-60 kyr, the biochronological age of Lang Trang (Long et al., 1996), or even Holocene. The Ma U’Oi site is important because of the scarcity of Vietnamese sites of those particular levels. For that reason, it fills a gap in the biostratigraphy of Vietnam and permits new correlations with other sites of the mainland, especially those well documented from Thailand

Etude des palokarsts des environs de Saint-Remze (Ardche, France) : mise en vidence dune rivire souterraine fossilise durant la crise de salinit messinienne, 2005, Martini, Jacques
Paleokarst investigation near Saint-Remze, Ardche, France discovery of an underground river fossilized during the Messinian salinity crisis - The paleokarst features studied in this paper are hosted in Lower Cretaceous limestone and generally appear as filled caves, subsequently de-roofed by denudation. The most important of them forms a sequence of segments developed at a relatively constant elevation of 360-380 m above sea level and can be traced over a length of 5.2 km. The ancient cave passages generally appear as soil covered bands, 5 to 20 m in width and limited on both sides by limestone outcrops. At surface the nature of the cave filling is revealed mainly by scattered blocks: calcite from speleothems and calcified clay, silt, sand and breccia. In the best preserved places, the earth band lies in a trench, where the walls may display a cave morphology and where the filling is often exposed in a undisturbed state. Three types of detrital cave filling have been identified, which in stratigraphical order are as follows: 1) Beige-grey silt, sand and microconglomerate of immature alluvials, with elements of Paleozoic granites and metamorphic rocks, and Upper Miocene volcanics, both originating from the Cvennes Mountains 30 km to the NW. The lithological composition is comparable to the recent alluvials of the Paleokarst investigation near Saint-Remze, Ardche, France discovery of an underground river fossilized during the Messinian salinity crisisArdche River, which is flowing a few kilometers to the SW and is deeply entrenched into a canyon at elevations of 40 to 80 m. The karst context, combined with the biostratigraphical data obtained from rodent molars in the alluvials, suggests an Uppermost Miocene age, comprised between ~5.8 and ~5.45 Ma. 2) Red mature alluvials and colluvials originating from local reworking of surficial karst residuals. At one spot they gave a paleontological age of 3.6 to 3.0 Ma, but from the local karst context one may expect ages from final Miocene to Pleistocene in other spots. 3) Monogenic breccia generated from wall gelifraction, which is Pleistocene after rodent molars found in two places. The paleocave is visualised as formed by an underground stream fed from swallow-holes on the bank of the Ardche River, when it was flowing more than 300 m higher than its actual bed. With regard to its relatively constant elevation and a discordant relationship with the country rock bedding, it is interpreted as a vadose cave controlled by a paleo-water-table. The other fillings (2 and 3) were deposited during subsequent vadose speleogenesis and after considerable water-table lowering. The elevation of this fossilised underground river coincides fairly well with the pre-salinity crisis abandonment surface (5.52 Ma), which is evidenced in the area by high perched gravel relics. The end of the speleogenesis could have taken place just before this event (~5.6 Ma) or at an age not younger than ~5.45 Ma. In the latter possibility, speleogenesis had to be working before the regressive erosion generated by the drastic lowering of the Mediterranean Sea [5.52 to 5.33 Ma, Clauzon et al, 2005 ] reached the area and de-watered the deep karst aquifer. This fossil underground river provides also information about the morphological evolution of the area. For instance the nature of the immature alluvials suggests that the torrential regime of the Ardche was about the same than today. It also indicates that the important and famous cave systems in the area (Grotte de Saint-Marcel, Aven dOrgnac, Systme de Foussoubie, Grotte Chauvet), which are developed at lower elevations, cannot be older than ~5.6 Ma and most likely formed mainly during the Plio-Pleistocene, although most of them have been initiated during the salinity crisis.

Environmental change across the Early-Middle Pleistocene transition: small mammalian evidence from the Trinchera Dolina cave, Atapuerca, Spain, 2005, Cuencabescos G, Rofes J, Garciapimienta J,
The sites of Atapuerca are well known for their hominin-bearing localities of Early to Middle Pleistocene age. Trinchera Dolina yields western Europe's oldest fossil hominin, the 850 ka Homo antecessor; and at Sima de los Huesos there occurs the best collection of the Middle Pleistocene hominin Homo heidelbergensis. However, small mammals (Rodentia, Insectivora, Chiroptera and Lagomorpha) represent the largest number of species and greatest fossil abundance in the deposits of the Atapuerca cave complex. The small mammals are grouped by habitat categories, but because the ecology of mammals is complex, we base our study on the evolution of these categories throughout the sequence. The assemblage distribution at the Trinchera Dolina site reflects landscape and environmental changes during the past million years. Shifts between woodland, open land and moorland are indicated by the relative abundance of species based on diagnostic elements such as first lower molars. These data are combined with the distribution of large mammals, pollen, sediments and geological context of the Trinchera Dolina site. From this interdisciplinary approach, we conclude that the first hominins from western Europe (Homo antecessor) lived during a warm, wet and wooded interval, probably corresponding to Marine Isotope Stages 21 to 19. The transition from Early to Middle Pleistocene at Atapuerca is characterized by palaeoenvironmental changes recorded between levels TD5-6 and TD8-10, respectively. The general opening of the landscape at the beginning of the Middle Pleistocene could have favoured the dispersal of hominins (Homo heidelbergensis) across western Europe

Fossil population structure and mortality of the cave bear from the Mokrica cave (North Slovenia), 2007, Debeljak, I.

The fossil population structure of the cave bear from the Mokrica cave was evaluated to provide new data concerning the behaviour and mortality of this extinct species. Age at death was estimated for 128 different individuals by analysing cementum increments, root formation and crown wear of left M1 teeth. After the frequency distribution of specimens through one- year intervals, the mortality trends can be estimated for various lifetime periods, and interpreted in accordance with data for present-day bears. The original death assemblage was presumably juvenile-dominated. Extremely fragile molars of less than 6 month old cubs did not get preserved. Yearlings are the most numerous age class in the fossil population from the Mokrica cave. Mortality drastically dropped after cave bears survived their first hibernation in the second winter. The lowest mortality rate was observed in the 9-15 years age group, when cave bears would be expected to be in their prime. The oldest age recorded by cementum analysis is approximately 30 years, which indicates that the maximum life span was similar to present-day bears. Study of dental tissues shows that the mortality in the cave was seasonally restricted – the majority of deaths in the cave occured during winter and in early spring. Sex structure of the fossil population has been studied on the sample of 750 canines. The significantly higher proportion of males in the group of older juveniles and subadults could be explained by the fact that the weaning period is more critical for males also in present- day bears. In young adults and prime adults the mortality was presumably higher in females. The sex structure of adult bears, especially in the sample of older individuals, indicates that the Mokrica cave was used as winter den mostly by solitary males.



This manuscript offers preliminary geochemical evidence that investigates the potential for hypogene speleogenesis in the Cumberland Plateau of southeastern Kentucky, U.S.A. The region was traditionally considered a classic example of epigenic karst, but new insights have uncovered tantalizing observations that suggest alternatives to simple carbonic acid speleogenesis. Such first-order observations have included natural petroleum seeps at the surface and in caves, occasional cave morphologies consistent with action of hypogene fluids, and prolific gypsum within cave passages. To this point, geochemical data from caves and springs verify carbonic acid as the primary dissolutional agent; however, these same analyses cannot rule out sulfuric acid as a secondary source of dissolution. In this paper, Principal Component Analysis of ionic data reveals two components that coordinate with parameters associated with “karst water” and shallow brine. In contrast, molar ratios of Ca+ and Mg+ as compared to HCO3 - and SO4 2- closely follow the reaction pathway stipulated by the carbonate equilibria reactions. Despite these data, the role, if any, of hypogene speleogenesis in the karst of the Cumberland Plateau remains inconclusive. It is very likely that carbonic acid dominates speleogenesis; however, contributions from sulfuric acid may influence our understanding of “inception” and carbon flux within these aquifers.

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