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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 induced recharge is a method of withdrawing ground water at strategic points to induce natural recharge [16].?

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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 deglaciation (Keyword) returned 21 results for the whole karstbase:
Showing 1 to 15 of 21
Uranium-Series Ages of Speleothem from Northwest England: Correlation with Quaternary Climate, 1983, Gascoyne M, Schwarcz Hp, Ford Dc,
Over 180 $^{230}$Th/$^{234}$U ages have been obtained for 87 speleothems from caves in the Craven district of northwest England. Periods of abundant speleothem growth, 0-13, 90-135 and 170 to > 350 ka, are correlated with interglacial isotope stages 1, 5 and 7-9 respectively. Periods of zero growth, 14-35 and 140-165 ka, are correlated with glacial stages 2 and 6 respectively. A prominent break in growth of one speleothem, dated at about 260 ka, may be correlated with glacial stage 8. Lower-frequency growth from 35 to 90 ka is correlated with stages 3 and 4. The results may also be related to the British Quaternary sequence within the range of $^{14}$C determinations, as follows: 0-13 ka. Flandrian plus late Devensian deglaciation; 14-35 ka, late Devensian glaciation; 35-45 ka. Upton Warren interstadial. Low but finite speleothem abundance during the period 45-90 ka correlates with the early Devensian and is in good agreement with evidence indicating the non-glacial, but tundra-like, climate over this period. The Ipswichian interglacial is broadly related to the abundant growth period 90-135 ka, but is more closely defined by the interval 115-135 ka, from results of dating speleothems enclosing remains of Ipswichian fauna in one cave. By analogy with the zero speleothem abundance during the late Devensian glaciation, the period 140-165 ka may be tentatively correlated with the Wolstonian glaciation. Lack of direct stratigraphic relationships with, or absolute ages of, middle to early Pleistocene stages prevents further correlation of speleothem age data. From the frequency of abundance of speleothem basal ages for the period 0-13 ka, it appears that speleothem growth lags ice recession by up to 4 ka

Late Wisconsinan deglaciation of Alberta: Processes and paleogeography, 1996, Mandryk C. A. S. ,
The scarcity of lake basins in Alberta dating earlier than 11,000 BP has been interpreted as indicating the continued presence of active glacial ice. Because of the related implication that the presence of ice precludes the existence of an ice-free corridor, it is useful to examine this issue more closely. Due to the effects of deglaciation, many areas of Alberta were dominated by chaotic ice-stagnation conditions, with continual reversal of topography and rapid transformation of the surface. The dynamic nature of the environment affects arguments regarding the existence of an ice-free corridor as well as having implications for archeological site formation, preservation and discovery. Deglaciation models utilizing paradigms of active ice retreat may result in dichotomous depictions of the land surface as either ice covered or deglaciated. Due to the insulating properties of supraglacial debris, stagnant ice results in a situation that is simultaneously neither and both of the above conditions. While the landscape is ice covered and thus not 'ice-free', an accessible landscape characterized by glacial karst topography exists on top of the stagnating ice surface. General reconstructions of the impact of stagnant ice and glacial karst topography on the paleogeography of Alberta are presented for discussion. Copyright (C) 1996 INQUA/Elsevier Science Ltd

Rapid Fluctuations in Sea Level Recorded at Huon Peninsula During the Penultimate Deglaciation, 1999, Esat Tm, Mcculloch Mt, Chappell J, Pillans B, Omura A,
About 140,000 years ago, the breakup of large continental ice sheets initiated the Last Interglacial period. Sea level rose and peaked around 135,000 years ago about 14 meters below present levels. A record of Last Interglacial sea levels between 116,000 years to 136,000 years ago is preserved at reef VII of the uplifted coral terraces of Huon Peninsula in Papua New Guinea. However, corals from a cave situated about 90 meters below the crest of reef VII are 130,000 2000 years old and appear to have grown in conditions that were 6 degrees C cooler than those at present. These observations imply a drop in sea level of 60 to 80 meters. After 130,000 years, sea level began rising again in response to the major insolation maximum at 126,000 to 128,000 years ago. The early (about 140,000 years ago) start of the penultimate deglaciation, well before the peak in insolation, is consistent with the Devils Hole chronology

Coral Record of Equatorial Sea-Surface Temperatures During the Penultimate Deglaciation at Huon Peninsula, 1999, Mcculloch Malcolm T. , Tudhope Alexander W. , Esat Tezer M. , Mortimer Graham E. , Chappell John, Pillans Bradley, Chivas Allan R. , Omura Akio,
Uplifted coral terraces at Huon Peninsula, Papua New Guinea, preserve a record of sea level, sea-surface temperature, and salinity from the penultimate deglaciation. Remnants have been found of a shallow-water reef that formed during a pause, similar to the Younger Dryas, in the penultimate deglaciation at 130,000 2000 years ago, when sea level was 60 to 80 meters lower than it is today. Porites coral, which grew during this period, has oxygen isotopic values and strontium/calcium ratios that indicate that sea-surface temperatures were much cooler (22 degrees 2 degrees C) than either Last Interglacial or present-day tropical temperatures (29 degrees 1 degrees C). These observations provide further evidence for a major cooling of the equatorial western Pacific followed by an extremely rapid rise in sea level during the latter stages of Termination II

Start of the last interglacial period at 135 ka: Evidence from a high Alpine speleothem, 2002, Spotl Christoph, Mangini Augusto, Frank Norbert, Eichstadter Rene, Burns Stephen J. ,
A detailed study of growth periods of a flowstone from Spannagel Cave in the Zillertal Alps (Austria) at [~]2500 m above sea level, a site highly sensitive to climate changes, offers unprecedented new insights into Pleistocene climate change in Central Europe. Flowstone sample SPA 52 has a high U content (to 116 ppm); analyses of this sample reveal that episodes of calcite deposition started at 204 {} 3 ka, 135 {} 1.2 ka, and 122 ka, suggesting that at these times, the mean air temperature at this high Alpine site was within 1.5 {degrees}C of the present-day condition. The beginning of growth at 135 ka corresponds to the ending of the last glaciation and is concordant with a midpoint age for the penultimate deglaciation at 135 {} 2.5 ka, as deduced from the absolutely dated oxygen isotope curve in sediments from the Bahamas, as well as with recent coral evidence from Barbados indicating a high sea level already by 135.8 {} 0.8 ka. This set of data supports evidence against Northern Hemisphere forcing of termination II, because the insolation maximum is at 127 ka

Constraints on Black Sea outflow to the Sea of Marmara during the last glacial-interglacial transition, 2002, Major Candace, Ryan William, Lericolais Gilles, Hajdas Irka,
New cores from the upper continental slope off Romania in the western Black Sea provide a continuous, high-resolution record of sedimentation rates, clay mineralogy, calcium carbonate content, and stable isotopes of oxygen and carbon over the last 20[punctuation space]000 yr in the western Black Sea. These records all indicate major changes occurring at 15[punctuation space]000, 12[punctuation space]800, 8400, and 7100 yr before present. These results are interpreted to reflect an evolving balance between water supplied by melting glacial ice and other river runoff and water removed by evaporation and outflow. The marked retreat of the Fennoscandian and Alpine ice between 15[punctuation space]000 and 14[punctuation space]000 yr is recorded by an increase in clays indicative of northern provenance in Black Sea sediments. A short return toward glacial values in all the measured series occurs during the Younger Dryas cold period. The timing of the first marine inflow to the Black Sea is dependent on the sill depths of the Bosporus and Dardanelles channels. The depth of the latter is known to be -805 m, which is consistent with first evidence of marine inundation in the Sea of Marmara around 12[punctuation space]000 yr. The bedrock gorge of the Bosporus reaches depths in excess of -100 m (relative to present sea level), though it is now filled with sediments to depths as shallow as -32 m. Two scenarios are developed for the connection of the Black Sea with the Sea of Marmara. One is based on a deep Bosporus sill depth (effectively equivalent to the Dardanelles), and the other is based on a shallow Bosporus sill (less than -35 m). In the deep sill scenario the Black Sea's surface rises in tandem with the Sea of Marmara once the latter connected with the Aegean Sea, and Black Sea outflow remains continuous with inflowing marine water gradually displacing the freshwater in the deep basin. The increase in the [delta]18O of mollusk shells at 12[punctuation space]800 yr and the simultaneous appearance of inorganic calcite with low [delta]18O is compatible with such an early marine water influx causing periodic weak stratification of the water column. In the shallow sill scenario the Black Sea level is decoupled from world sea level and experiences rise and fall depending on the regional water budget until water from the rising Sea of Marmara breaches the shallow sill. In this case the oxygen isotope trend and the inorganic calcite precipitation is caused by increased evaporation in the basin, and the other changes in sediment properties reflect climate-driven river runoff variations within the Black Sea watershed. The presence of saline ponds on the Black Sea shelf circa 9600 yr support such evaporative draw-down, but a sensitive geochemical indicator of marine water, one that is not subject to temperature, salinity, or biological fractionation, is required to resolve whether the sill was deep or shallow

Symposium Abstract: The deglaciation of Central Scandanavia and its implications for karst cave environment, 2004, Faulkner T.

Variability of Southwest Indian summer monsoon precipitation during the Bolling-Allerod, 2005, Sinha Ashish, Cannariato Kevin G. , Stott Lowell D. , Li Hong Chun, You Chen Feng, Cheng Hai, Edwards R. Lawrence, Singh Indra B. ,
We have generated a high-resolution (<20 yr) 230Th-dated stalagmite oxygen isotope record from Timta Cave in the western Himalaya in India that documents Southwest Indian summer monsoon (ISM) precipitation variations during the Bolling-Allerod interstadial from 15.2 to 11.7 ka. Compared with the glacial and Younger Dryas, ISM precipitation was enhanced during the Bolling-Allerod. ISM precipitation was apparently coupled to variations in the East Asian monsoon and North Atlantic climate on millennial and multicentennial time scales during the deglaciation. Analyses of a high growth rate interval (<2.5 yr resolution) encompassing the late Bolling-early Allerod suggest that multidecadal monsoon variability was an important aspect of ISM behavior at that time. The frequency spectrum of ISM precipitation during this time interval is similar to that of the {Delta}14C record and other ISM precipitation records during the latest Holocene. This raises the hypothesis that multidecadal climate dynamics during the late Bolling-early Allerod may have been similar to those that operated during the last several millennia, even though the boundary conditions of these two time intervals were very different

Cave inception and development in Caledonide metacarbonate rocks. PhD thesis, 2005, Faulkner, Trevor Laurence

This is the first comprehensive study of cave inception and development in metacarbonate rocks. The main study area is a 40000km2 region in central Scandinavia that contains over 1000 individual metacarbonate outcrops, and has nearly 1000 recorded karst caves (with passage lengths up to 5.6km). The area, which was repeatedly glaciated in the late Cenozoic, comprises a suite of nappes in the Cambro–Silurian Caledonides, a paleic range of mountains with terranes presently occurring on both sides of the northern Atlantic. Information about the stripe karst and non-stripe karst outcrops and their contained caves was assembled into computer-based databases, enabling relationships between the internal attributes of the caves and their external geological and geomorphological environments to be analysed. A rather consistent pattern emerged. For example, karst hydrological system distances are invariably shorter than 3.5km, and cave passages are positioned randomly in a vertical dimension, whilst commonly remaining within 50m of the overlying surface. This consistency is suggestive that the relevant cave inception, development and removal processes operated at a regional scale, and over long timescales. A consequence of the epigean association of caves with the landscape is that cave development can only be understood in the context of the geomorphological evolution of the host region. A review of the latest knowledge of the inception and development of caves in sedimentary limestones concluded that the speleogenesis of the central Scandinavian caves cannot be explained by these ideas. Five new inter-related conceptual models are constructed to explain cave development in metacarbonate rocks in the various Caledonide terranes. These are:
1. The tectonic inception model - this shows that it is only open fracture routes, primarily created by the seismic shocks that accompany deglaciation, which can provide the opportunity for dissolution of metalimestone rocks that have negligible primary porosity.
2. The external model of cave development - this black-box approach reveals how the formation, development and destruction of the karst caves are related to the evolution of their local landscape. During the Pleistocene, these processes were dominated by the cycle of glaciation, leading to cyclic speleogenesis, and the development of ever-longer and deeper systems, where the maximum distance to the surface commonly remains within one-eighth of the extent of change in local relief.
3. The hydrogeological model - this demonstrates that the caves developed to their mapped dimensions in timescales compatible with the first two models, within the constraints imposed by the physics and chemistry of calcite dissolution and erosion, primarily in almost pure water. Relict caves were predominantly formed in phreatic conditions beneath active deglacial ice-dammed lakes, with asymmetric distributions on east- and west-facing slopes. Mainly vadose caves developed during the present interglacial, primarily vadose, conditions, with maximum dimensions determined by catchment area. Combination caves developed during both deglacial and interglacial stages. The cross-sections of phreatic passages obey a non-fractal distribution, because they enlarged at maximum rates in similar timescales. Phreatic cave entrances could be enlarged at high altitudes by freeze / thaw processes at the surface of ice-dammed lakes, and at low altitudes by marine activity during isostatic uplift.
4. The internal static and dynamic model of cave development - this white-box approach demonstrates that many caves have ‘upside-down’ morphology, with relict phreatic passages overlying a single, primarily vadose, streamway. Both types of passage are guided along inception surfaces that follow the structural geology and fractures of the carbonate outcrops. Dynamically, the caves developed in a ‘Top-Down, Middle-Outwards’ (TDMO) sequence that may have extended over several glacial cycles, and passages in the older multi-cycle caves were removed downwards and inwards by glacial erosion.
5. The Caledonide model - this shows that the same processes (with some refinements) applied to cave development in most of the other (non-central Scandinavian) Caledonide areas. The prime influences on cave dimensions were the thicknesses of the successive northern Atlantic glacial icesheets and the positions of the caves relative to deglacial ice-dammed lakes and to local topography. Other influences included contact metamorphism, proximity to major thrusts, and marine incursions. With knowledge of these influences for each area, mean cave dimensions can be predicted.
The thesis provides the opportunity for the five models to be extended, so that cave development in other glaciated metamorphic and sedimentary limestones can be better understood, and to be inverted, so that landscape evolution can be derived from cave data.


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

Timing and dynamics of the last deglaciation from European and North African [delta]13C stalagmite profiles--comparison with Chinese and South Hemisphere stalagmites, 2006, Genty D, Blamart D, Ghaleb B, Plagnes V, Causse C, Bakalowicz M, Zouari K, Chkir N, Hellstrom J, Wainer K, Bourges F,
The last deglaciation and its climatic events, such as the Bolling-Allerod (BA) and the Younger-Dryas (YD), have been clearly recorded in the [delta]13C profiles of three stalagmites from caves from Southern France to Northern Tunisia. The three [delta]13C records, dated by thermal ionization mass spectrometric uranium-thorium method (TIMS), show great synchroneity and similarity in shape with the Chinese cave [delta]18O records and with the marine tropical records, leading to the hypothesis of an in-phase (between 15.5 and 16 ka ~0.5 ka) postglacial warming in the Northern Hemisphere, up to at least 45[deg]N. The BA transition appears more gradual in the speleothem records than in the Greenland records and the Allerod seems warmer than the Bolling, showing here close similarities with other marine and continental archives. A North-South gradient is observed in the BA trend: it cools in Greenland and warms in our speleothem records. Several climatic events are clearly recognizable: a cooler period at about 14 ka (Older Dryas (OD)); the Intra-Allerod Cold Period at about ~13.3 ka; the YD cooling onset between 12.7 and 12.90.3 ka. Similar to the BA, the YD displays a gradual climate amelioration just after its onset at 12.750.25 ka, up to the Preboreal, and is punctuated by a short climatic event at 12.15 ka. Even though the Southern Hemisphere stalagmite records seem to indicate that the postglacial warming started about ~3 ka1.8 ka earlier in New Zealand (~41 [deg]S), and about ~1 to ~2 ka earlier in South Africa (24.1 [deg]S), large age uncertainties, essentially due to slow growth rates, make the comparison still perilous. The overall [delta]13C speleothem record seems to follow a baseline temperature increase controlled by the increase in insolation and punctuated by cold events possibly due to the N-America freshwater lake discharges

The co-evolution of Black Sea level and composition through the last deglaciation and its paleoclimatic significance, 2006, Major Candace O. , Goldstein Steven L. , Ryan William B. F. , Lericolais Gilles, Piotrowski Alexander M. , Hajdas Irka,
The Black Sea was an inland lake during the last ice age and its sediments are an excellent potential source of information on Eurasian climate change, showing linkages between regionally and globally recognized millennial-scale climate events of the last deglaciation. Here, we detail changes from the last glacial maximum (LGM) through the transition to an anoxic marginal sea using isotopic (strontium and oxygen) and trace element (Sr/Ca) ratios in carbonate shells, which record changing input sources and hydrologic conditions in the basin and surrounding region. Sr isotope records show two prominent peaks between ~18 and 16 ka BP cal, reflecting anomalous sedimentation associated with meltwater from disintegrating Eurasian ice sheets that brought Black Sea level to its spill point. Following a sharp drop in Sr isotope ratios back toward glacial values, two stages of inorganic calcite precipitation accompanied increasing oxygen isotope ratios and steady Sr isotope ratios. These calcite peaks are separated by an interval in which the geochemical proxies trend back toward glacial values. The observed changes reflect negative water balance and lake level decline during relatively warm periods (Bolling-Allerod and Preboreal) and increasing river input/less evaporation, resulting in higher lake levels, during the intervening cold period (the Younger Dryas). A final shift to marine values in Sr and oxygen isotope ratios at 9.4 ka BP cal corresponds to connection with the global ocean, and marks the onset of sedimentation on the Black Sea continental shelf. This date for the marine incursion is earlier than previously suggested based on the appearance of euryhaline fauna and the onset of sapropel formation in the deep basin

The top-down, middle-outwards model of cave development in central Scandinavian marbles, 2007, Faulkner, Trevor.
The epigean marble caves in the glaciated metamorphic Caledonides of central Scandinavia provide a rare environment in which endokarstic morphologies and other internal cave attributes have been studied against variations in foliation dip and topographical characteristics, to produce a common static internal model of cave existence. This paper proposes a dynamic model to explain the sequential developments of cave passage elements from inception fractures that are created seismically during isostatic uplift. The speleogenesis is driven by Cenozoic glacial cycles consisting of periods of glaciation, deglaciation and interglaciation. The more complex caves have evolved top-downwards in deglacial phreatic conditions under ice-dammed lakes and subsequently along their lowest levels in interglacial vadose conditions, with later extensions upstream and downstream. Glacial erosion also removes passages in a topdown order, but with passage extremities being eroded away inwards.

Pedestal formation and surface lowering in the Carboniferous Limestone of Norber and Scales Moor, Yorkshire, UK, 2007, Parry, Brian.
he formation of Carboniferous limestone pedestals with vertical sidewalls beneath Devensian erratics at Norber, has taken place primarily in a sub-regolith karstic environment; little or no formation occurred prior to c.10,000BP. In contrast, the formation of pedestals with sloping sidewalls on Scales Moor has taken place largely in a subaerial karstic environment; formation of subaerial pedestals commenced at c.14,500BP in England and Wales, and c.13,700BP in Ireland. Measured heights of pedestals indicate that the post-Devensian-deglaciation inter-pedestal Carboniferous limestone surface has been lowered by a mean of about 46cm in a sub-regolith environment and about 15cm in a subaerial environment.

Palaeoclimate Research in Villars Cave (Dordogne, SW-France)., 2008, Genty D.
Villars Cave is a typical shallow cave from South-West France (45.44N; 0.78E; 175 m asl) that has provided several speleothem palaeoclimatic records such as the millennial scale variability of the Last Glacial period and the Last Deglaciation. Monitoring the Villars cave environment over a 13-year period has helped in the understanding of the stable isotopic speleothem content and in the hydrology. For example, it was demonstrated that most of the calcite CaCO3 carbon comes from the soil CO2, which explains the sensitivity of the ?13C to any vegetation and climatic changes. Drip rate monitoring, carried out under four stalactites from the lower and upper galleries, has shown a well marked seasonality of the seepage water with high flow rates during winter and spring. A time delay of about two months is observed between the water excess (estimated from outside meteorological stations) and the drip rate in the cave. A great heterogeneity in the flow rate amplitude variations and in the annual quantity of water between two nearby stalactites is observed, confirming the complexity of the micro-fissure network system in the unsaturated zone. At a daily scale, the air pressure and drip rates are anti-correlated probably because of pressure stress on the fissure network. Cave air CO2 concentration follows soil CO2 production and is correlated with its ?13C content. Since the beginning of the monitoring, the cave air temperature, in both lower and upper galleries, displays a warming trend of ~+0.4C0.1/10yrs. This might be the consequence of the outside temperature increase that reaches the Villars Cave galleries through thermal wave conduction. Chemistry monitoring over a few years has shown that the seepage water of the lower gallery stations is significantly more concentrated in trace and minor elements (i.e. Sr, Mg, Ba, U) than the upper stations, probably due to the 10-20 m depth difference between these galleries, which implies a different seepage pathway and different water/rock interaction durations. There is also, in the elemental concentration (i.e. [Ca]), a seasonal signal which causes variation in the speleothem growth rates. Modern calcite deposit experiments conducted for several years have permitted the calculation of vertical growth rates, which are extremely high in Villars (i.e. 1.0 to 1.75 mm/ yr). Pollen filter experiments in the cave have demonstrated that most of the pollen grain found in the cave comes from the air and not from the water. The specificity of the Villars Cave records is that the climatic variations were well recorded in the calcite ?13C whereas the ?18O is usually used in such studies. Overall, these results are helpful for the interpretation of speleothem records for palaeoclimatic reconstructions, but more work is needed, especially numerical modelling of the temperature, chemistry and hydrology.

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