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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 demand is the rate of draft from an aquifer or reservoir to meet a certain demand [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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Showing 16 to 30 of 76
Forme et rugosit des surfaces karstiques. Consquences pour une thorie spatiale et fractale de linterface terrestre, 2000, Martin, Philippe
This text proposes a theoretical, hypothetical and speculative approach of the transformation of earth's surfaces. This reflection is based on the notion of otherness. Our approach uses two oppositions: levelled/ roughness and karstic/ non karstic. The dimension of the roughness surfaces is understood between 2 and 3. The dimension of the surfaces of levelling is close to 2. Quantifications showed that massifs are limited by surfaces more or less irregular. In certain cases, the erosion transforms so a surface of levelling into rough surface. In that case initial shape is not preserved. The levellings on the karstic massifs (outliers often) seem better preserved (karstic immunity) than on the other rocks. This conservation would explain a weak value of the fractal dimension of air surfaces of karsts tested always with the same protocol (relation S PD). They were compared with the surfaces of reliefs of basal complex. Three ideas summarise obtained results: [1] The average of fractal dimensions of karsts are smaller than those of the relief of basal complex. [2] The dispersal of the mean values of surface of karst is lower to the dispersal of the mean values of basal complex. [3] Distance between minimal and maximal values for karsts is much bigger than distance between minimal and maximal values for basal complex. To explain the weak roughness of karsts we made three hypotheses: [a] These fragments would correspond to zones still not affected by the erosion (time problem) [b] In such a system some changes on a plan would prevent changes on the another plan (spatial problem) [c] Initial shape is replaced by a similar shape (Platon's Parmnide). The endokarst is described empirically and by analogy with the fractal model of Sierpinski's sponge as a unique surface infinitely folded up in a limited volume. So the growth of the karstic spaces in the endokarst, increases almost until the infinity, the size of the internal surface of the karst. To find a theoretical base at the roughness and at the extreme size of these surfaces, we studied the report between the growth of a volume and the growth of the surface, which limits this volume. Three theoretical models show that if surfaces do not change, volume to be affected by unity of surface grows strongly. Eroded volume depends on the size of the exposed surface. If the eroded volume depends on the size of the exposed surface, then time to erase a mountain could be, in theory, infinite. This is not acceptable because a massif can be erased in about 200 Ma. According to analogies with different morphogenesis (physical, biologic), we make the hypothesis that fractal character, of surfaces of the massifs corresponds to the necessity of increasing, as much as possible, the size of the surface subjected to the erosion so as to decrease the time of destruction of the relief. This is coherent with the idea of a system far from the balance, which tends to join the state of balance as quickly as possible by developing specific morphologies. Distance between the relief and the lower limit of the potential of erosion is then introduced as a factor being able to explain the small roughness of high continental surfaces. The reduction of the volume by erosion is cause (and not consequence) of the decrease of the roughness. The surface can become less rough because volume decreases. The surface of levelling constitutes the final morphology, which is transformed only very slowly. In this perspective the dynamics allows only the fulfillment of spatial rules. In the case of the karst, because of the existence of the subterranean part of the karstic surface and its roughness, it is not useful that air part becomes very rough. Levellings would be preserved by geometrical uselessness to destroy them. They would not correspond to forms in respite as implies him the temporal analysis (hypothesis [a]), but to forms corresponding to a particular balance (hypothesis [b]) who would even be locally transformed (karstic levelling) into the same shape (hypothesis [c]). This theoretical plan supplies with more an explanation on the visible contradiction between the speed of the karstic erosion and the durability of levellings.

Le karst des Arbailles (Pyrnes-Atlantiques, France), 2000, Vanara, Nathalie
The Arbailles massif (200 - 1200 m) is located in the french north face of Pyrnes, Atlantic side. It forms a folded 165 square-kilometres unit of jurassic and cretaceous limestones under an oceanic climate of altitude (2000 mm/year). Observations jointly made on the surface and in the numerous underground galleries allow an occurate correlation of alternate surrective and karstic periods. The dismantled cavities and deposits pockets of the upper surface show two series of minerals, those from weathered marly-albian limestones and others supplied from the conglomerates pudding-stones of Mendibelza. During the Miocene, the Arbailles massif is a low area of tropical erosion on the side of the main mounts. Its surrection caused the scouring of the alterites cover, the formation of fields of karstic butts and a definitive drying of the fluviatile paleosystem. The different levels of dried valleys and the karstic hydrographic systems are successive stations of the karstic levels of origine. Paleomagnetic datations in Etxanko Zola and U/Th datations in Nbl show that the surrection has been of about 500 m since lower Pleistocene. At the present time, water collection is made through drainage systems without any connection to the fossil topography. Three aquifers can be distinguished: in lower cretaceous, in jurassic and in north and south limits. They are water-repellent because of more or less impermeable screens. Waters are aggressive in summer and at equilibrium or lightly undersaturated the rest of the year. The modern human activities create a recent destabilisation of the environment with local erosions of grounds and an increasing turbidity of springs. An occurate study in the fail of Istaurdy allows a mesure of the effect of deforestation for the whole massif.

Revision of a few hypotheses on speleogenesis, 2000, Choppy Jacques
Quite often, as we know better karst phenomena and the evolution of the karst environment, several hypotheses on speleogenesis appeared to be flimsy. Some of these hypotheses, concerning processes playing a part in the creation of karst forms, exceed the limits of their field. Others suggest hydraulic mechanisms, and interventions of geological or geographical factors likely to be questioned. Hypotheses relating to the evolution of karst, as well as the classification of karst types, suffer from the lack of an analytical approach. However, some of these hypotheses still have an important place in the current vision of speleologists and karstologists.

Verification of the causes of glaciations and sea level changes using the records of calcite speleothems, 2000, Forti Paolo, Georgiev Leonid, Georgieva Desislava, Lundberg Joyce, Sanabria Michael, Shopov Yavor, Stoykova Diana, Tsankov Ludmil
The luminescence of calcite speleothems displays an exponential dependence on soil temperature unless there is a dense cover of forest over the cave to dampen it. This relationship is determined primarily by the strength of solar visible and infrared radiation. It is suggested that, as a consequence, the microzonal variations of luminescence often found in speleothems can be used as a proxy index of Solar Insolation. The luminescence solar insolation proxy record of a speleothem from Jewel Cave, South Dakota, USA, was found to display millenial and centennial cycles in the record. It exhibits a rapid increase in solar insolation at 139 5.5 kyrs. This increase precedes that suggested by the Orbital theory by about 10,000 years and is due to superimposition of the most powerful cycle in solar luminosity of 11.5 kyrs, upon the curve of orbital variations. The record from a speleothem in Duhlata Cave, Bulgaria matches that of South Dakota within the limits of dating error, indicating that both of these records (which are 10,000 km apart) measure global solar insolation controls rather than local paleotemperature variations.

Determination of escarpment age using morphologic analysis: An example from the Galilee, northern Israel, 2000, Matmon A. , Zilberman E. , Enzel Y. ,
We used topographic and structural data and very limited age control to perform quantitative morphometric analyses and to determine relative ages of escarpments bounded by late Cenozoic normal faults in the Galilee, Israel. The Galilee is an extensional zone composed of a series of uplifted and tilted blocks forming large escarpments built mainly of carbonate rocks. Two parameters used to discriminate tectonic stages are the ratio between the height of the escarpment and the total stratigraphic displacement (L) and the degree of concavity of escarpment slopes relative to a reference slope. The only dated reference slope is Mount Tur'an, [~]300 m high and formed by the Tur'an fault system, which has a total stratigraphic displacement of 625 m. A basalt flow that delimits the age of the Tur'an escarpment is dated to 4.23 {} 0.23 Ma and displaced 300 m, which is identical to the present-day topographic expression of this escarpment. The L value for this escarpment is [~]0.5. The Tur'an fault system was active prior to 4.23 Ma at slow uplift rates that enabled erosion to maintain the gentle slope over which the basalt flowed. Increased offset rates following the basalt extrusion led to the formation of the escarpment. The preservation of the basalt at the top of the escarpment indicates that erosional lowering of the upper surface of the Tur'an block has been minor since its formation. The L values indicate two stages of uplift; an early stage during which offset rates were probably low enough that they did not form topography, and a later stage that formed topography, which is preserved. The timing of the change in displacement rates from a slow continuous stage to a fast, topography-forming stage was determined by comparing the shape of the dated slope of Tur'an to that of other slopes. We conclude the following: (1) generally, the topographic profiles of different parts of each individual escarpment have similar shapes indicating similar ages; (2) escarpments having slopes that are more concave or convex than the reference Tur'an escarpment are older or younger than 4 Ma, respectively; and (3) the Galilee escarpments did not form simultaneously. A few escarpments were already major morphologic features by the early to middle Pliocene, whereas the rest formed during the late Pliocene. Morphometric analysis is a useful method for studying the geologic history of a landscape controlled by normal fault uplift and characterized by the absence of sediment deposition and where carbonate dissolution is the main erosional process. This and similar approaches can be used to discriminate tectonic stages and understand the relationship between tectonic activity and surface processes in other extensional regions

Exploration techniques for karst groundwater resources., 2001, Bakalowicz M.
Porous and fissure aquifers display statistical homogeneity of their physical and hydraulic characteristics on a scale ranging from tens to several hundreds of meters. Such homogeneity is a product of the relatively small spatial variability of these characteristics and creates conditions of general hydraulic continuity throughout the entire saturated zone. Their groundwater resources can be explored by a simple approach, i.e. defining the aquifer geometry from geological data, and determining local hydraulic parameters from pumping tests; finally, the local data are extended to characterise the entire aquifer through regionalizing techniques. However, within the infiltration and saturated zones of carbonate aquifers, karst processes create a peculiar void heterogeneity : voids may reach several meters in diameter and several kilometers in length. These voids are organized in a hierarchic network from the input surface often to a single spring: this is the conduit or drainage network. Therefore the network should be fully characterized prior to assessing the groundwater resources of a karst aquifer and its possible storage capacity, i.e. the network's transmissive or drainage function and its links with storage components (its storage function). Traditionally, speleological exploration is considered the best technique for directly characterizing a drainage network. Unfortunately, this usually gives an incorrect view of the karst aquifer because only a few parts (or none at all) are known when there is no access to the saturated zone. The classical hydrogeological approach is thus unsuitable for assessing karst aquifers. In this context, karst hydrogeologists must adopt the classical approach of physicians and biologists examining living bodies, by characterizing a karst aquifer, its resources and storage by accurate description of the void organization and an analysis of its overall behavior (or functioning) and that of its different parts or organs. With such an approach, a karst aquifer is considered as a living organism composed of different types of organs interlinked by functional relationships. Unlike physicians, hydrogeologists generally have to discover the extent of the body they wish to study (the karst system as a drainage unit, its limits and the boundary conditions). Therefore, as in the field of medicine^ techniques are used for describing the aquifer in bi- or tri-dimensional space (geology, geophysics) and for characterizing its functioning (hydrodynamics, natural tracing, hydrological balance). Moreover, data from these techniques are interpreted in order to propose a diagnosis, i.e. for building a conceptual model of the studied aquifer. In the next step, as in medicine, the conceptual model can be assessed with localized tests, such as artificial tracing and diver exploration for borehole positioning and pumping tests. Methods for interpreting tracing and pumping tests must obviously be adapted to the specific nature of karst, i.e. they cannot be based on classical models whose basic assumptions are never verified in the karstic medium. Finally, karst hydrogeologists have to set up and implement a complex set of techniques for describing the extent and limits of a karst system, exploring its drainage pattern, and analyzing its behaviour. All geoscience disciplines are ultimately required for the comprehensive exploration of groundwater resources in karst aquifers.

McCauley sinks: a compound breccia pipe in evaporite karst, Holbrook Basin, Arizona, U.S.A., 2001, Neal J. T. , Johnson K. S.
The McCauley Sinks, in the Holbrook basin of northeastern Arizona, are comprised of some 50 individual sinkholes within a 3-km-wide depression. The sinks are grouped in a semi-concentric pattern of three nested rings. The outer ring is an apparent tension zone containing ring fractures. The two inner rings are semicircular chains of large sinkholes, ranging up to 100 m across and 50 m deep. Several sub-basins within the larger depression show local down warping and possible incipient sinkholes. Permian Kaibab Formation limestone is the principal surface lithology; the limestone here is less than 15 m thick and is near its easternmost limit. Although surface rillenkarren are present, and the sinks are seen in the Kaibab limestone outcrops, the Kaibab is mainly a passive rock unit that has collapsed into solution cavities developed in underlying salt beds. Beneath the Kaibab is Coconino Sandstone, which overlies the Permian Schnebly Hill Formation, the unit containing the evaporite rocks principally halite in the Corduroy Member. Evaporite karst in this part of the Holbrook basin is quite different from the eastern part, probably because of the westward disappearance of the Holbrook anticline, a structure that has major joint systems that help channel water down to the salt beds farther to the east. Also, the McCauley Sinks are near the western limits of the evaporites. The structure at McCauley Sinks suggests a compound breccia pipe, with multiple sinks contributing to the inward-dipping major depression. The Richards Lake depression, 5 km southeast of McCauley Sinks, is similar in form and size but contains only a single, central sinkhole. An apparent difference in hydrogeology at McCauley Sinks is their proximity to the adjacent, deeply incised, Chevelon Canyon drainage, but the hydrologic connections are unknown.

McCauley Sinks: a compound breccia pipe in evaporite karst, Holbrook basin, Arizona, USA, 2002, Neal J. T. , Johnson K. S. ,
The McCauley Sinks, in the Holbrook basin of northeastern Arizona, are comprised of some 50 individual sinkholes within a 3-km wide depression. The sinks are grouped in a semi-concentric pattern of three nested rings. The outer ring is an apparent tension zone containing ring fractures. The two inner rings are semi-circular chains of large sinkholes, ranging up to 100 in across and 50 in deep. Several sub-basins within the larger depression show local downwarping and possible incipient sinkholes. Permian Kaibab Formation limestone is the principal surface lithology; the limestone here is less than 15 in thick and is near its easternmost limit. Although surface rillenkarren are present, and the sinks are seen in the Kaibab limestone outcrops, the Kaibab is mainly a passive rock unit that has collapsed into solution cavities developed in underlying salt beds. Beneath the Kaibab is Coconino Sandstone, which overlies the Permian Schnebly Hill Formation, the unit containing the evaporite rocks-principally halite in the Corduroy Member. Evaporite karst in this part of the Holbrook basin is quite different from the eastern part, probably because of the westward disappearance of the Holbrook anticline, a structure that has major joint systems that help channel water down to the salt beds farther to the east. Also, the McCauley Sinks are near the western limits of the evaporites. The structure at McCauley Sinks suggests a compound breccia pipe, with multiple sinks contributing to the inward-dipping major depression. The Richards Lake depression, 5 kin southeast of McCauley Sinks, is similar in form and size but contains only a single, central sinkhole. An apparent difference in hydrogeology at McCauley Sinks is their proximity to the adjacent, deeply incised, Chevelon Canyon drainage, but the hydrologic connections are unknown. The 3-km-wide McCauley Sinks karst depression, along with five other nearby depressions, provide substantial hydrologic catchment. Because of widespread piping into karst features and jointed bedrock at shallow depth, runoff water does not pond easily at the surface. There appears to be a greater recharge efficiency here than in alluvial areas; thus concern exists for groundwater users downgradient from the karst area. Accordingly, sinkholes and open fissures should not be used for waste disposal

Karst groundwater basin delineation, Fort Knox, Kentucky, 2002, Connair Dp, Murray Bs,
Evaluation of karst groundwater quality concern at Fort Knox Kentucky has required the development of a sitewide karst groundwater flow model and basin delineation investigation. The karst aquifer underlying Fort Knox is developed within approximately 60 m of the St. Louis Limestone and is bounded on three sides by surface streams that represent the local base level. The underlying Salem Limestone acts as a regional aquitard and provides a lower limit to karst aquifer development. The study area covers over 130 km(2) and contains over 200-inventoried karst features. As a part of this investigation, innovative multiple dye trace events were conducted throughout the study area using up to six dyes per event with a total of eight dyes used to conduct 14 dye traces during three seasonal events. Dye trace results, structural and topographic controls, spring characteristics, and normalized base flow were used to establish groundwater basin limits and boundary zones and to develop a conceptual sitewide groundwater flow model. The primary finding of this work indicates sitewide groundwater flow is controlled directly or indirectly by local stratigraphy, geologic structure, and changes in stream levels in the geologic past, and that two groundwater basins dominate the study area, accounting for approximately 80% of measured sitewide groundwater discharge. The findings of this investigation will be used to assess the groundwater contaminant contribution from source areas in individual basins, develop an effective groundwater monitoring program, and guide future groundwater management strategies. (C) 2002 Published by Elsevier Science B.V

Interpretation of spring recession curves, 2002, Amit H, Lyakhovsky V, Katz A, Starinsky A, Burg A,
Recession curves contain information on storage properties and different types of media such as porous, fractured, cracked lithologies and karst. Recession curve analysis provides a function that quantitatively describes the temporal discharge decay and expresses the drained volume between specific time limits (Hall 1968). This analysis also allows estimating the hydrological significance of the discharge function parameters and the hydrological properties of the aquifer. In this study, we analyze data from perennial springs in the Judean Mountains and from others in the Galilee Mountains, northern Israel. All the springs drain perched carbonate aquifers. Eight of the studied springs discharge from a karst dolomite sequence, whereas one flows out from a fractured, slumped block of chalk. We show that all the recession curves can be well fitted by a function that consists of two exponential terms with exponential coefficients alpha(1) and alpha(2). These coefficients are approximately constant for each spring, reflecting the hydraulic conductivity of different media through which the ground water flows to the spring. The highest coefficient represents the fast flow, probably through cracks, or quickflow, whereas the lower one reflects the slow flow through the porous medium, or baseflow. The comparison of recession curves from different springs and different years leads to the conclusion that the main factors that affect the recession curve exponential coefficients are the aquifer lithology and the geometry of the water conduits therein. In normal years of rainy winter and dry summer, (Xi is constant in time. However, when the dry period is longer than usual because of a dry winter, (X, slightly decreases with time

Factors controlling the chemical evolution of travertine-depositing rivers of the Barkly karst, northern Australia, 2002, Drysdale Rn, Taylor Mp, Ihlenfeld C,
Groundwaters feeding travertine-depositing rivers of the northeastern segment of the Barkly karst (NW Queensland, Australia) are of comparable chemical composition, allowing a detailed investigation of how the rate of downstream chemical evolution varies from river to river. The discharge, pH, temperature, conductivity and major-ion concentrations of five rivers were determined by standard field and laboratory techniques. The results show that each river experiences similar patterns of downstream chemical evolution, with CO2 outgassing driving the waters to high levels of calcite supersaturation, which in turn leads to widespread calcium carbonate deposition. However, the rate at which the waters evolve, measured as the loss of CaCO3 per kilometre, varies from river to river, and depends primarily upon discharge at the time of sampling and stream gradient. For example, Louie Creek (Q = 0.11 m(3) s(-1)) and Carl Creek (Q = 0.50 m(3) s(-1)) have identical stream gradients, but the loss of CaCO3 per kilometre for Louie Creek is twice that of Carl Creek. The Gregory River (Q = 3.07 m(3) s(-1)), O'Shanassy River (Q = 0.57 m(3) s(-1)) and Lawn Hill Creek (Q = 0.72 m(3) s(-1)) have very similar gradients, but the rate of hydrochemical evolution of the Gregory River is significantly less than either of the other two systems. The results have major implications for travertine deposition: the stream reach required for waters to evolve to critical levels of calcite supersaturation will, all others things being equal, increase with increasing discharge, and the length of reach over which travertine is deposited will also increase with increasing discharge. This implies that fossil travertine deposits preserved well downstream of modern deposition limits are likely to have been formed under higher discharge regimes. Copyright (C) 2002 John Wiley Sons, Ltd


The paper deals with the activities of the Cave Protection Department of the Slovak Caves Administration in the field of speleoclimatic monitoring in the Slovakian show caves since 1996. The monitoring is concentrated on detail survey of basic climatic parameters processes (temperature, relative air humidity, dew point, air velocity, atmospheric pressure etc.) in by now studied show caves during minimally one year. The essence of obtained knowledge is to enhance cave protection in the practice of show caves, better understand the geoecosystems; determine visitors' influence, the period of regeneration and evaluation of possible negative influences. The results of the monitoring are used for determining the carrying capacity of individual caves, limits for visitors, guiding the manageiant and other necessary measures. Presented caves were surveyed by priorities like: World Heritage site, ice caves, natural air mass communication with surface climate, potential threats - all in relation to cave utilization and operation. Technical eqqipment, as well as research methodology are described in detail in the paper.

Etude glaciologique et climatologique des cavits glaces du Moncodeno (Grigna septentrionale, province de Lecco, Lombardie, 2003, Turri S. , Citterio M. , Bini A. , Maggi V. , Udistj R. , Stenni B.
GLACIOLOGICAL AND CLIMATOLOGICAL STUDIES IN ICE-CAVES OF MONCODENO (NORTH GRIGNA, PROVINCEOFLECCO, LOMBARDY) - The existence of perennial ice and snow deposits in the karst shafts of the Moncodeno area, at altitudes of about 1800 to 2100 m a.s.l, has long been known. Even so, no detailed study has been formerly carried out. Three ice and snow cores have been drilled in the glaciated cave environment and chemical, isotopic, crystallographic and textural analyses were carried out on them. By linking these observations with the morphology, stratigraphy and internal structures of the deposits, and with the hypogean and epigean climate records, we were able to identify the accumulation processes and to give one upper and some lower limits to the age of these deposits. The most notable deposit shows a more than 15 m thick succession of clear-ice layers, found at a depth of about 80 m and suspended between two shafts in the cave "Abisso sul margine dell'Alto Bregaia Because of the relative position to the cave entrance, no snow can reach this deposit. The crystallographic and textural features, confirmed by the chemical and isotopic trends, show that this is lake-ice. At present no accumulation can be observed and the top surface is now at least 3 m lower than it was three decades ago. The underlying shaft, deglaciated at some time in the past by the air circulation drains the water so that hypogean lakes can no more develop. We have found sound stratigraphic and glaciotectonic evidences of at least three accumulation and three ablation phases. When compared to local present precipitations and to the values available from literature, the ice chemical composition and 6110 values show that this ice must be younger than the end of the last ice age, while preceding the beginning of industrial activity related contributions.

Karst morphology and cave sediments as indicators of the uplift history in the Alpi Apuane (Tuscany, Italy), 2003, Piccini Leonardo, Drysdale Russell, Heijnis Henk,
In the Alpi Apuane (Tuscany, Italy), Late Pliocene to Pleistocene karst landforms are preserved as relict phreatic caves, which were formed in a geomorphic setting very different from that of the present day. The largest karst drainage basin in the region, the Frigido, hosts cave systems with a vertical development totalling 1600 m. Abandoned phreatic cave passages preserved within this and neighbouring basins indicate that former base-levels were situated at up to ~1000 m above the modern valley floors. The passages constitute morphostratigraphic markers that can be used to reconstruct the uplift history of the Apuane. Their vertical distribution suggests two major phases of base-level standstill--one at 1000-1200 m a.s.l. and one at 600-700 m a.s.l. Some of the passages situated at the latter level contain >5 m thick flowstones whose top-beds have an age exceeding the limits of U/Th alpha spectrometric dating (>350 ka). Cave morphology and chronological constraints obtained from speleothems suggest that an important uplift event occurred during the Middle Pleistocene following a period of tectonic standstill of probable latest Early Pleistocene age. Active spring caves close to present-day valley floors contain speleothems whose ages exceed 100 ka, implying that no significant downcutting of the seaward valleys, and consequently no tectonic uplift, has occurred during Late Pleistocene

Numerical analysis of conduit evolution in karstic aquifers. PhD Thesis, 2003, Annable, W. K.

Fractured and solutionally enhanced carbonate aquifers supply approximately 20 percent of the Worlds potable water supply. Although in rare cases these geologic settings can geochemically evolve into conduits which are of sufficient size to be explored and interpreted by researchers, the majority of the solutionally enlarged networks providing fresh water supplies remain too small to be directly measured. As such, we rely upon indirect hydraulic testing and tracer studies to infer the complexity and size of such aquifers. Because solutionally enhanced (karstic) aquifers have multiple scales of porosity ranging from matrix flow, fracture flow and open channel conduit flow, they are particularly vulnerable to contamination due to the high rates of chemical transport. In this study, a numerical model which solves for the variably-saturated flow, chemically-reactive transport and sediment transport within fractured carbonate aquifers has been developed to investigate the evolution of proto conduits from discrete fractures towards the minimum limits of caves which can be explored. The model results suggest that, although potentiometric surfaces can be of assistance in forecasting the possible locations of proto conduits at depth, many conduits are never detected using conventional observation wells relying upon hydraulic head data. The model also demonstrates the strong dependence in the pattern of vertical jointing on how conduits may evolve: fractures oriented similar to the mean groundwater flow direction show conduits evolving along the vertical fracture orientation; however, vertical fractures that differ significantly from the mean groundwater flow direction have vastly more complex dissolution networks. The transport of fine-grained sediments within the fractures has been shown to reduce the rates of conduit development in all but the highest velocity regions, resulting in simplified conduit networks, but at accelerated dissolution rates. The fully-coupled advective-dispersive and reactive chemistry equations were employed strictly with equilibrium reactions to simulate calcite dissolution. This study further shows that higher order kinetics in the form of the kinetic trigger effect of White (1997) are not required if diffusion between the rock matrix and the fracture surfaces account for multi-component matrix diffusion effects between the evolving conduits and the carbonate rock matrix according to the diffusional characteristics of the fractured rock system at hand.

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