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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 water invasion is the sudden invasion of water into a well or borehole [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 analog (Keyword) returned 85 results for the whole karstbase:
Showing 16 to 30 of 85
Analoge Formen im Karst und in Gletschern, 1995, Spiegler, A.

Structure et comportement hydraulique des aquifers karstiques, DSc thesis, 1996, Jeannin, P. Y.

This thesis aims to provide a better knowledge of karst flow systems, from a functional point of view (behaviour with time), as well as from a structural one (behaviour in space). The first part of the thesis deals with the hydrodynamic behaviour of karst systems, and the second part with the geometry of karstic networks, which is a strong conditioning factor for the hydrodynamic behaviour.
Many models have been developed in the past for describing the hydrodynamic behaviour of karst hydrogeological systems. They usually aim to provide a tool to extrapolate, in time and/or space, some characteristics of the flow fields, which can only be measured at a few points. Such models often provide a new understanding of the systems, beyond what can be observed directly in the field. Only special field measurements can verify such hypotheses based on numerical models. This is an significant part of this work. For this purpose, two experimental sites have been equipped and measured: Bure site or Milandrine, Ajoie, Switzerland, and Holloch site, Muotathal, Schwyz, Switzerland. These sites gave us this opportunity of simultaneously observe hydrodynamic parameters within the conduit network and, in drillholes, the "low permeability volumes" (LPV) surrounding the conduits.
These observations clearly show the existence of a flow circulation across the low permeability volumes. This flow may represent about 50% of the infiltrated water in the Bure test-field. The epikarst appears to play an important role into the allotment of the infiltrated waters: Part of the infiltrated water is stored at the bottom of the epikarst and slowly flows through the low permeability volumes (LPV) contributing to base flow. When infiltration is significant enough the other part of the water exceeds the storage capacity and flows quickly into the conduit network (quick flow).
For the phreatic zone, observations and models show that the following scheme is adequate to describe the flow behaviour: a network of high permeability conduits, of tow volume, leading to the spring, is surrounded by a large volume of low permeability fissured rock (LPV), which is hydraulically connected to the conduits. Due to the strong difference in hydraulic conductivity between conduits and LPV, hydraulic heads and their variations in time and space are strongly heterogeneous. This makes the use of piezometric maps in karst very questionable.
Flow in LPV can be considered as similar to flow in fractured rocks (laminar flow within joints and joints intersections). At a catchment scale, they can be effectively considered as an equivalent porous media with a hydraulic conductivity of about 10-6 to 10-7 m/s.
Flow in conduits is turbulent and loss of head has to be calculated with appropriate formulas, if wanting any quantitative results. Our observations permitted us to determine the turbulent hydraulic conductivity of some simple karst conduits (k', turbulent flow), which ranges from 0.2 to 11 m/s. Examples also show that the structure of the conduit network plays a significant role on the spatial distribution of hydraulic heads. Particularity hydraulic transmissivity of the aquifer varies with respect to hydrological conditions, because of the presence of overflow conduits located within the epiphreatic zone. This makes the relation between head and discharge not quadratic as would be expected from a (too) simple model (with only one single conduit). The model applied to the downstream part of Holloch is a good illustration of this phenomena.
The flow velocity strongly varies along the length of karst conduits, as shown by tracer experiments. Also, changes in the conduit cross-section produce changes in the (tow velocity profile. Such heterogeneous flow-field plays a significant role in the shape of the breakthrough curves of tracer experiments. It is empirically demonstrated that conduit enlargements induce retardation of the breakthrough curve. If there are several enlargements one after the other, an increase of the apparent dispersivity will result, although no diffusion with the rock matrix or immobile water is present. This produces a scale effect (increase of the apparent dispersivity with observation scale). Such observations can easily be simulated by deterministic and/or black box models.
The structure of karst conduit networks, especially within the phreatic zone, plays an important role not only on the spatial distribution of the hydraulic heads in the conduits themselves, but in the LPV as well. Study of the network geometry is therefore useful for assessing the shape of the flow systems. We further suggest that any hydrogeological study aiming to assess the major characteristics of a flow system should start with a preliminary estimation of the conduit network geometry. Theories and examples presented show that the geometry of karst conduits mainly depends on boundary conditions and the permeability field at the initial stage of the karst genesis. The most significant boundary conditions are: the geometry of the impervious boundaries, infiltration and exfiltration conditions (spring). The initial permeability field is mainly determined by discontinuities (fractures and bedding planes). Today's knowledge allows us to approximate the geometry of a karst network by studying these parameters (impervious boundaries, infiltration, exfiltration, discontinuity field). Analogs and recently developed numerical models help to qualitatively evaluate the sensitivity of the geometry to these parameters. Within the near future, new numerical tools will be developed and will help more closely to address this difficult problem. This development will only be possible if speleological networks can be sufficiently explored and used to calibrate models. Images provided by speleologists to date are and will for a long time be the only data which can adequately portray the conduit networks in karst systems. This is helpful to hydrogeologists. The reason that we present the example of the Lake Thun karst system is that it illustrates the geometry of such conduits networks. Unfortunately, these networks are three-dimensional and their visualisation on paper (2 dimensions) is very restrictive, when compared to more effective 3-D views we can create with computers. As an alternative to deterministic models of speleogenesis, fractal and/or random walk models could be employed.


Structure et comportement hydraulique des aquifers karstiques, DSc. Thesis, faculte des Sciences de l'Universite de Neuchatel., 1998, Jeannin Py.
This thesis aims to provide a better knowledge of karst flow systems, from a functional point of view (behaviour with time), as well as from a structural one (behaviour in space). The first part of the thesis deals with the hydrodynamic behaviour of karst systems, and the second part with the geometry of karstic networks, which is a strong conditioning factor for the hydrodynamic behaviour. Many models have been developed in the past for describing the hydrodynamic behaviour of karst hydrogeological systems. They usually aim to provide a tool to extrapolate, in time and/or space, some characteristics of the flow fields, which can only be measured at a few points. Such models often provide a new understanding of the systems, beyond what can be observed directly in the field. Only special field measurements can verify such hypotheses based on numerical models. This is an significant part of this work. For this purpose, two experimental sites have been equipped and measured: Bure site or Milandrine, Ajoie, Switzerland, and Holloch site, Muotathal, Schwyz, Switzerland. These sites gave us this opportunity of simultaneously observe hydrodynamic parameters within the conduit network and, in drillholes, the "low permeability volumes" (LPV) surrounding the conduits. These observations clearly show the existence of a flow circulation across the low permeability volumes. This flow may represent about 50% of the infiltrated water in the Bure test-field. The epikarst appears to play an important role into the allotment of the infiltrated waters: Part of the infiltrated water is stored at the bottom of the epikarst and slowly flows through the low permeability volumes (LPV) contributing to base flow. When infiltration is significant enough the other part of the water exceeds the storage capacity and flows quickly into the conduit network (quick flow). For the phreatic zone, observations and models show that the following scheme is adequate to describe the flow behaviour: a network of high permeability conduits, of tow volume, leading to the spring, is surrounded by a large volume of low permeability fissured rock (LPV), which is hydraulically connected to the conduits. Due to the strong difference in hydraulic conductivity between conduits and LPV, hydraulic heads and their variations in time and space are strongly heterogeneous. This makes the use of piezometric maps in karst very questionable. Flow in LPV can be considered as similar to flow in fractured rocks (laminar flow within joints and joints intersections). At a catchment scale, they can be effectively considered as an equivalent porous media with a hydraulic conductivity of about 10-6 to 10-7 m/s. Flow in conduits is turbulent and loss of head has to be calculated with appropriate formulas, if wanting any quantitative results. Our observations permitted us to determine the turbulent hydraulic conductivity of some simple karst conduits (k',turbulent flow), which ranges from 0.2 to 11 m/s. Examples also show that the structure of the conduit network plays a significant role on the spatial distribution of hydraulic heads. Particularity hydraulic transmissivity of the aquifer varies with respect to hydrological conditions, because of the presence of overflow conduits located within the epiphreatic zone. This makes the relation between head and discharge not quadratic as would be expected from a (too) simple model (with only one single conduit). The model applied to the downstream part of Holloch is a good illustration of this phenomena. The flow velocity strongly varies along the length of karst conduits, as shown by tracer experiments. Also, changes in the conduit cross-section produce changes in the (tow velocity profile. Such heterogeneous flow-field plays a significant role in the shape of the breakthrough curves of tracer experiments. It is empirically demonstrated that conduit enlargements induce retardation of the breakthrough curve. If there are several enlargements one after the other, an increase of the apparent dispersivity will result, although no diffusion with the rock matrix or immobile water is present. This produces a scale effect (increase of the apparent dispersivity with observation scale). Such observations can easily be simulated by deterministic and/or black box models. The structure of karst conduit networks, especially within the phreatic zone, plays an important role not only on the spatial distribution of the hydraulic heads in the conduits themselves, but in the LPV as well. Study of the network geometry is therefore useful for assessing the shape of the flow systems. We further suggest that any hydrogeological study aiming to assess the major characteristics of a flow system should start with a preliminary estimation of the conduit network geometry. Theories and examples presented show that the geometry of karst conduits mainly depends on boundary conditions and the permeability field at the initial stage of the karst genesis. The most significant boundary conditions are: the geometry of the impervious boundaries, infiltration and exfiltration conditions (spring). The initial permeability field is mainly determined by discontinuities (fractures and bedding planes). Today's knowledge allows us to approximate the geometry of a karst network by studying these parameters (impervious boundaries, infiltration, exfiltration, discontinuity field). Analogs and recently developed numerical models help to qualitatively evaluate the sensitivity of the geometry to these parameters. Within the near future, new numerical tools will be developed and will help more closely to address this difficult problem. This development will only be possible if speleological networks can be sufficiently explored and used to calibrate models. Images provided by speleologists to date are and will for a long time be the only data which can adequately portray the conduit networks in karst systems. This is helpful to hydrogeologists. The reason that we present the example of the Lake Thun karst system is that it illustrates the geometry of such conduits networks. Unfortunately, these networks are three-dimensional and their visualisation on paper (2 dimensions) is very restrictive, when compared to more effective 3-D views we can create with computers. As an alternative to deterministic models of speleogenesis, fractal and/or random walk models could be employed.

Pollen and Other Microfossils in Pleistocene Speleothems, Kartchner Caverns, Arizona, 1999, Davis, O. K.
Pollen and other microfossils have been recovered from six carbonate speleothems in three Kartchner Caverns rooms: Grand Central Station (samples T2, T3, T4), the Bathtub Room (T11, T12), and Granite Dells (T16). The carbonate samples were dated from 194-76 Ka. The pollen concentration is greatest (~2 grain/cm?) in sample T11, which has many layers of clastic sediment, and the concentration is least in T4 (~0.05 grain/cm?), which has few mud layers. Therefore, the pollen was probably present in sediments washed into the cave, perhaps during floods. Although the pollen abundance in sample T4 is too low for confident interpretation, modern analogs for the five other samples can be found on the Colorado Plateau in areas that today are wetter and colder than the Kartchner Caverns locality. Agave pollen in samples T2 and T4 indicates that this important source of nectar was in the area during at least the latter part of the Pleistocene. Two orobatid mite exoskeletons recovered in speleothem T4 were probably washed into the cave with the pollen and mud trapped in the speleothems.

Facies differentiation and sequence stratigraphy in ancient evaporite basins - An example from the basal Zechstein (Upper Permian of Germany), 1999, Steinhoff I. , Strohmenger C. ,
Due to excellent preservation, the Werra Anhydrite (Al), the upper member of the Upper Permian Zechstein cycle I (Ist cycle, Z1), is readily studied in terms of the distribution of sulfate facies and sequence stratigraphy that can be interpreted from these facies. In this study cores taken from seven wells in the Southern Zechstein Basin were examined for their sedimentary structures and various petrographic features. Facies interpretation and depositional sequences are based on detailed examination of core material. Four main facies environments have been identified: (I) supratidal (II) intertidal (III) shallow subtidal, and (IV) deeper (hypersaline) subtidal. These are further subdivided into 10 subfacies types: (1) karst and (2) sabkha within the supratidal environment (I), (3) algal tidal-flat, (4) tidal flat and (5) beach deposit within the intertidal environment (II), (6) salina, and (7) sulfate arenites within the shallow subtidal enviromnent (III). The (8) slope subfacies type commonly associated with (9) turbidites and the (10) basin subfacies type subdivide the deeper subtidal environment (IV). Vertical stacking patterns of these facies and subfacies types reveal the sequence stratigraphic development of the sulfate cycles in response to sea-level and salinity fluctuations. The lower Werra Anhydrite (belonging to Zechstein Sequence ZS2) is characterized by a transgressive systems tract (IST) overlying the transgressive surface of Zechstein Sequence ZS2 within the Al-underlying upper Zechstein Limestone (Cal). The TST of the AT is several tens of meters thick in platform areas, where it is built up by sulfate arenites and swallow-tail anhydrite-after-gypsum, and thins out to a few meters of thickness toward the condensed basinal section, where laminites ('Linien-Anhydrit') are predominant. Most of the Al succession consists of three relatively thick parasequences belonging to the highstand systems tract (HST) that shows typical prograding sets. Enhanced platform Buildup, including sulfate arenites, salina deposits, intertidal sediments, and sabkha precipitation as well as turbidite shedding off the platforms produced marginal ''sulfate walls' up to 400 m thick as platform to slope portions of the Werra Anhydrite. Seaward, the Al thins to a few tens of meters of laminated sulfate basin muds. Increasingly pronounced Al topography during highstand narrowed the slope subfacies belt parallel to the platform margin This contrasts with the broad but considerably thinner slope deposits of transgressive times with much shallower slopes. The ensuing sea-level lowstand is reflected by a sequence boundary on top of the karstified Al-platform and a lowstand wedge (Zechstein Sequence ZS3) overlying portions of the slope and basinal subfacies of the Al highstand systems tract Beyond the lateral limits of the lowstand wedge, the sequence boundary merges with the transgressive surface of ZS3, shown by the lithologic change from the Al anhydrites to the overlying carbonates of the Stassfurt Carbonates ('Haupt Dolomit' Main Dolomite, Ca2). The Basal Anhydrite (A2), which overlies and seals the carbonate reservoir of the Ca2, can also be subdivided into systems tracts by means of facies analysis. It is, however, much less complex than the Al and is comprised almost exclusively of a transgressive systems tract of Zechstein Sequence ZS4

Sand speleothems: an Australian example, 1999, Grimes, K. G.

Sand speleothems have formed in sea caves at Loch Ard Gorge, Victoria, Australia, by the localised precipitation of calcium carbonate in loose sand that fills the caves. Calcite-saturated waters have entered the caves from the surrounding porous limestone, either dripping onto the sand, or seeping directly into it from the walls. Removal of the uncemented sand has exposed the cemented formations which have shapes analogous to those of conventional stalagmites, stalactites and shelves.


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.

Carbonate platform systems: components and interactions -- an introduction, 2000, Insalaco Enzo, Skelton Peter, Palmer Tim J. ,
Carbonate platforms are open systems with natural boundaries in space and time. Across their spatial boundaries there are fluxes of energy (e.g. light, chemical energy in compounds, and kinetic energy in currents and mass flows) and matter (e.g. nutrients, dissolved gases such as CO2, and sediment -- especially, of course, carbonates). Internally, these fluxes are regulated by myriads of interactions and feedbacks (Masse 1995), and the residue is consigned to the geological record. The most distinctive aspect of carbonate platforms is the predominant role of organisms in producing, processing and/or trapping carbonate sediment, even in Precambrian examples. Because of evolutionary changes in this strong biotic input, it is harder to generalize about carbonate platforms than about most other sedimentary systems. Evolution has altered both the constructive and destructive effects of platform-dwelling organisms on carbonate fabrics, with profound consequences for facies development. Moreover, changing patterns in the provision of accommodation space (e.g. between greenhouse and icehouse climatic regimes) have also left their stamp on facies geometries, in turn feeding back to the evolution of the platform biotas. Hence simplistic analogies between modern and ancient platforms may give rise to misleading interpretations of what the latter were like and how they formed. Although a number of carbonate platform and reef specialists have warned of the dangers of such misplaced uniformitarianism (e.g. Braithwaite 1973; Gili et al. 1995; Wood 1999), it remains depressingly commonplace in the literature on ancient carbonate platforms. The endless quest in the literature for an allpurpose definition of reefs' ... This 250-word extract was created in the absence of an abstract

Hydrologic analysis of discharge sustainability from an abandoned underground coal mine, 2000, Burbey Tj, Younos T, Anderson Et,
Discharge from flooded abandoned subsurface coal mines is considered a potential source for water supplies where other acceptable water sources are not available. The objective of this study was to develop procedures for determining sustainability of mine-water discharge using rainfall and discharge data for a case study site. The study site is located in southwest Virginia where Late Paleozoic sequences of sandstone, coal, and shale predominate. A rain gauge and a flow rate monitoring system were installed at the site and data were collected for a period of 100 days. The recording period corresponded with one of the driest periods in recent years and, therefore, provided valuable information regarding the flow sustainability during baseflow conditions. From available data on underground mining patterns, geology, and ground water flow regimes, it was determined that a coal mine aquifer exhibits hydraulic characteristics very similar to the extremely heterogeneous systems observed in karst aquifers, and the mine discharge is analogous to springflow. Thus, techniques commonly used in karst-water systems and springflow analysis were used to develop rainfall/mine-discharge relationships. Springflow recession analysis was performed on five rainfall recessions and the coefficient for each recession was compared and interpreted in light of known geologic information. It was found that the recession coefficients described the mine discharge adequately and the mine aquifer response to a rainfall pulse was very similar to the response from certain ts;pes of karst aquifers. A cross-correlation analysis was performed to verify the results of the recession analysis and to develop a 'black box' statistical model for discharge data. The correlation analysis proved the validity of springflow recession analysis for mine discharge. The recorded data length was not adequate to create a statistical model, however, but a procedure was proposed for a statistical model that could be used with large flow records. For the study site, the mine discharge was found to be sustainable for a prolonged period of time

Hardware and software modeling of initial conduit development in karst rocks, 2000, Ford D. , Lauritzen S. E. , Ewers R. O.
Most dissolutional conduits develop along fissures (bedding planes, joints or faults) in which the initial opening varies considerably from place to place, i.e. they are anisotropic. The propagation of conduits between input and output points in an anisotropic fissure was studied systematically with three types of hardware models: (1) electrical current analogs and (2) sandbox analogs, to investigate flowfield geometry; (3) artificial fissures cast in Plaster of Paris, with random anisotropic elements on their surfaces. A first series of experiments studied the case of a single input to the fissure. The earliest proto-conduits were observed to extend in radial (Darcian) array but one principal and several secondary tubes quickly extended down the hydraulic gradient, robbing competitors of their flow. This mode of propagation was tested with a resistor network computer model using 100 by 100 nodes, Weyl's (1958) equation for dissolution and transport with parameters appropriate for plaster, and three choices of opening - isotropic, anisotropic but homogeneous, heterogeneous. The computer model results closely matched those of the hardware models. In second and third series of plaster hardware experiments, the cases of (1) multiple inputs to the fissure in one rank, and (2) multiple inputs in multiple ranks, were explored. In the competition between inputs, some principal tubes in near ranks first breakthrough to the output boundary. This re-orients the flowfields of failed nearby competitors, which then extend to join the principal via their closest secondaries. The process extends outwards and to the rear, linking up all inputs in a cascading system.

Groundwater Flow and Contaminant Transport in Carbonate Aquifers, 2000, Sasowsky I. D. , Wicks C. M.
Carbonate aquifers are an important source of water throughout the world. They are complicated systems and not always easy to interpret. Caves and channels form in the rock, leading to complex flow pathways and unpredictable contaminant behaviour. This volume covers the range of techniques used to analyse groundwater flow and contaminant transport in carbonate aquifers. The book opens with a review of thoughts and methods, and continues by discussing the use of tracers, hydrograph and hydrochemograph evaluation, estimation of aquifer properties from outcrop studies, numerical simulation, analogue simulation, and 3-D visualization of conduits. Other papers address the critical evaluation of matrix, fracture and conduit components of flow and storage. An understanding of these approaches is important to engineers or hydrogeologists working in carbonate aquifers.

Controls on the geochemistry of speleothem-forming karstic drip waters, PhD thesis, 2000, Tooth, A.

Research was performed at Crag Cave, Castleisland, southwest Ireland, and P8 Cave, Castleton, Derbyshire, in order to determine the main factors responsible for modifying rainwater geochemistry during flow through soil and karstic aquifer zones. Monitoring was performed on a daily basis in summer and winter at Crag Cave, and on a monthly basis over one year at P8 Cave. At both sites, biannual peaks in karst system Ca2+ concentrations occurred due to: (i) promotion of microbial CO2 production by increased summer temperatures, and (ii) retardation of gaseous exchange by ponding of elevated winter rainfall input leading to an unseasonable build up in soil zone CO2. Therefore, speleothems at both sites may form biannual bands in hydrological years subject to elevated winter rainfall input.

In addition to variations in carbonate weathering due to fluctuations in CO2 levels, cation yields in Crag Cave matrix soil water were controlled by dolomite dissolution (Mg2+), plant uptake (K+), and evapotranspiration balanced by enhanced winter marine aerosol input (Na+). Strontium isotope analysis indicates that Sr2+ was derived from a 50:50 silicate/carbonate mixture, whereas the relatively light ?13C signal was related to direct evolution of CO2 into the aqueous phase in water-logged pores.

Within the Crag Cave aquifer variations in karst water geochemistry were controlled by dilution, flow switching, prior precipitation of calcite, and dolomite dissolution along the flow path. Strontium isotope analysis indicates that dissolution in the aquifer dominated, with Sr2+ being sourced from a 25:75 silicate/carbonate mixture. Light karst water 13C values were constrained by the supply of light soil gas to the aquifer.

Elevation in the Mg/Ca and Sr/Ca ratios in the Crag Cave speleothem record compared to present day analogues indicates that the former Holocene climate was drier, whereas heavier 87Sr/86Sr ratios and 13C values suggest variation in soil hydrology over time.


Gypsum-karst collapse in the Black Hills, South Dakota-Wyoming, USA, 2000, Epstein, Jack B.

Intrastratal dissolution of gypsum and anhydrite in four stratigraphic units of Pennsylvanian to Jurassic age in the Black Hills of South Dakota and Wyoming has resulted in many collapse features that have developed primarily in the non-soluble overlying rocks. Subsidence has affected several areas that are undergoing urban development. Subsurface intrastratal dissolution of anhydrite in the Minnelusa Formation has produced a regional collapse breccia, extensive disruption of bedding, many dolines, and breccia pipes and pinnacles, some of which extend upwards more than 300 m into overlying strata. Recent collapse is evidenced by steep-walled dolines more than 20 m deep, collapse in water wells and natural springs resulting in sediment disruption and contamination, and fresh circular scarps surrounding shallow depressions. Many beds of gypsum are contorted because of expansion due to its hydration from anhydrite, and many gypsum veinlets extend downward along random fractures from parent gypsum beds. Several dolines are sites of resurgent springs. As the anhydrite dissolution front in the subsurface Minnelusa moves downdip and radially away from the center of the Black Hills uplift, these resurgent springs will dry up and new ones will form as the geomorphology of the Black Hills evolves. Old dolines and breccia pipes, preserved in cross section on canyon walls, attest to the former position of the dissolution front. Mirror Lake, which is expanding northwestward in a downdip direction, is a local analog of a migrating dissolution front.


Mn-Fe deposits in shallow cryptic marine environment: examples in northwestern Mediterranean submarine caves, 2001, Allouc J, Harmelin Jg,
Black coating of hard substrates by Mn and Fe oxides has long been reported from shallow, dark, submarine caves. However, these littoral metallic deposits have never been studied in detail, despite expected analogies with deep-sea polymetallic crusts. Submarine caves are characterized by darkness and low rates of exchanges with the open sea. Lack of primary production and confinement of inner water bodies result in marked oligotrophy and extremely reduced biomass, i.e. conditions close to those prevailing in deep-sea habitats. Field evidences suggested that the formation of Mn-Fe coatings was closely tied to these particular environmental conditions. The goal of this study was to examine the detailed features of Mn-Fe coatings from dark caves with different local conditions, and to try to identify the processes responsible for their deposition. Study sites and methods Three sublittoral, single-entrance, caves were sampled by scuba diving along the coasts of Provence (France, Mediterranean Sea) (fig. 1). The first site is a large karstic cave (Tremies Cave, 16 m depth at entrance floor, 60 m long; Marseille-Cassis area) with an ascending profile which results in a buffered thermal regime and markedly oligotrophic conditions due to warm water trapping in its upper part (fig. 1 and 2). Wall fragments were sampled at 30 m (medium confinement : zone B) and 60 in (strong confinement : zone C) from the cave entrance. The second site is a large tubular cavity open in conglomerate formations (3PP Cave, 15 m depth at entrance floor, 120 m long; La Ciotat) with a descending profile which results in relative permanence of winter temperatures within the inner parts, complex water circulation and presumed greater input of sedimented particles than in the preceding cave (fig.1 and 2). Wall samples were taken at 25 m, 70 in and 100 m from entrance. The third site is a small, horizontal, cave open in quartzite formations (Bagaud Cave, 7 in depth at entrance floor, about 10 m long; WNW of Port-Cros Island, bay of Hyeres). Sampling was performed on walls of a narrow corridor between an anterior room and a smaller inner room. A sporadic outflow of continental waters is located in the inner room. The samples were preserved in 50% ethylic alcohol or studied soon after their sampling. Before carbon coating and SEM examination, or microanalyses with SEM-associated spectrometers, they were treated in a 33% Chlorox solution and thereafter washed in demineralized water and dried. Micromorphology At low-medium magnification (<20,000), the aspect of coatings varies between caves and, especially, between inner-cave locations. All the described structures are made up of Mn and Fe oxides. In Tremies Cave, coatings of walls from zone B are composed of irregular erected constructions (height : 10s to 100s μm) formed by the aggregation of roughly ovoid primary concretions of about 10 μm (fig. 3). The surface of those primary concretions displays numerous lacunose to reticulate films (pores, about 0.5 μm in diameter, are often subrounded). Remnants of these films and organomorphic corpuscles occur also within the primary concretions (fig. 4). On younger substrates (broken wall exposed since 1970), primary concretions are poorly developed and no prominent construction is visible (fig. 5). In more confined conditions (zone C), the erected constructions of ancient coatings are smaller and less numerous than in zone B but are well individualized (fig. 6). In this zone: C, besides some remnants of lacunose to reticulate films (fig. 7), there is an appearance of filaments and ovoid corpuscles (height/width : 10-30/5-15 μm), which seem to be linked to filaments by a short stalk (fig. 8). In 3 PP Cave, at 25-70 m from entrance, wall coatings present porous heaps of primary concretions (fig. 9). The surface and the inside of the latter comprise remnants of lacunose to reticulate films that evoke those observed in Tremies Cave (fig. 10 and 11). On younger substrates (hard parts of sessile invertebrates), coatings are restricted to micrometric organomorphic corpuscles with some remnants of lacunose or fibrous films (fig. 12). At 100 in from the entrance, coatings are shaped by numerous erected constructions, more or less coalescing (fig. 13). Besides remnants of lacunose films, the primary concretions contain interlacing filaments (diameter : 0.2-0.3 μm) forming cords or veils (fig. 14). In Bagaud Cave, the primary concretions are aggregated in irregular heaps (fig. 15). Lacunose films are particularly frequent and tend to form three-dimensional mamillated structures that were not observed in the other caves (fig. 16). In particular, there is an appearance of tubular structures (fig. 17) and of numerous hemispheroidal structures (diameter : 4-5 μm) with an upper orifice (fig. 18 and 19). At higher magnification (20,000), whatever the cave and inner-cave location, the aspect of oxide deposits is rather smooth or, especially, microgranular (fig. 20). Mineral composition The composition of coatings is different between caves and according to their inner-cave location. In both large caves (Tremies and 3 PP), the Mn/Fe ratio increases with the distance from the cave entrance, i.e. when exchanges with the open sea diminish (fig. 21a). This trend is particularly clear in Tremies Cave, where the confinement gradient is strongly marked. Besides, the Mn/Fe ratio also seems to increase when films are present in the analysed volume (some cubic micrometers) (fig. 21b). In Bagaud Cave, the Mn/Fe ratio reaches high values despite the small size of this cave and its low confinement level. Discussion and conclusions SEM observations suggest that in each studied cave, the Mn-Fe coatings are biosedimentary deposits. Genesis of these deposits is assumed to result mainly from the replacement of biofilms (composed of cells and slime, i.e, of extracellular polymeric substance produced by microorganisms) generated by microbial populations colonizing the cave walls. Considering the darkness of the cave-locations, microbes consist mainly in bacteria, but fungi are probably responsible for the filaments and ovoids corpuscules (evoking sporocysts) occurring in innermost parts. Observations at different scales of the morphological features of oxide deposits reveal a structured organisation which varies along the strong environmental gradients (particularly the confinement level) that occur from the entrance to the innermost parts : erected constructions made up of primary concretions become more and more defined and acquire a pseudo-columnar shape. The aspect of biofilms appears to be controlled by the same environmental parameters. In open or relatively open environments, they frequently show a three-dimensional development (with frequent skullcape-like shapes), while in more confined conditions they exhibit a planar layout. These changes reflect either the adaptation of the slime-producing bacteria to the local trophic resources (correlated to the rate of exchange with the open sea) and water movements, or spatial replacement of taxa. It is assumed that slime (mainly composed of water and exopolysaccharides) induces a local increase of the concentration in dissolved Mn and acts as an ion exchange resin that allows the retention of Mn on the functional groups of EPS. These conditions promote the nucleation of Mn oxide crystallites in the slime. Then. the anionic character of Mn oxides in seawater, and their capacity to catalyse the oxydation of Mn2 to Mn4, allow the process to go on without any other biological intervention; thus, the process of crystal growth becomes possible. In caves where Mn is only supplied by seawater (Tremies and 3 PP), the average value of the Mn/Fe ratio of coatings is negatively correlated to the local availability of nutrients. This trend is probably linked to changes in the selectivity of slimes towards the processes of retention of cations, because this ratio is clearly influenced by the occurrence of biofilms. However, independently from trophic resources, the Mn/Fe ratio can be notably increased when additional Mn is provided by the seeping or flowing of continental waters (Bagaud Cave)

Partitioning of Sr2 and Mg2 into calcite under karst-analogue experimental conditions, 2001, Huang Yiming, Fairchild Ian J. ,
There is a paucity of experimental data on calcite precipitation from waters at low ionic strength and low ratios of Mg/Ca and Sr/Ca, using controlled and constant precipitation rates. Such data are particularly needed for studies of speleothem geochemistry in relation to palaeoclimates.We carried out a series of experiments using a karst-analogue set-up in a chamber of constant temperature and 100% humidity. A steady flow of NaHCO3 and CaCl2 solutions at PCO2 around 10-3.2 were mixed just before passage through a tube (analogous to a soda-straw stalactite) and allowed to drip onto a surface, analogous to a stalagmite. Growth rates were comparable with linear extension rates of natural speleothems.Analytical spots gave reproducible analyses in later analytical cycles after ablation of surface calcite with Na and Mg contamination. Different crystals from the same experiment tended to show positive covariation of Na and Mg with negative covariation with Sr. This may be due to the presence of growth hillocks with vicinal faces with differential partitioning behaviour.The result for the partition coefficient for Mg (DMg) at 25[deg]C is 0.031 0.004, which is quantitatively in good agreement with the trends of previous workers. At 15[deg]C, the result is 0.019 0.003. The temperature dependency is higher than experimental data on seawater-analogue solutions, but lower than a previous estimate based on a comparison of speleothem chemistry with single water analyses.Data for DSr are mainly in the range of 0.057 to 0.078, with a possible weak dependency on growth rate, consistent with previous experimental work. Absolute values are higher than studies in Mg-free saline solutions, which is attributed mainly to salinity effects. Values of DSr are nevertheless somewhat lower than in natural caves, which may relate to crystal growth factors.Mg partition coefficient values should allow robust determination of solution Mg/Ca compositions in enclosed caves, which are at constant temperature on the decadal timescale. The inferred sensitivity of DSr to growth rate factors implies that Sr values should be interpreted more cautiously. Muted changes could relate entirely to growth rate variations, whereas changes of large magnitude imply a control by solution composition. The absence of local (tens of micron scale) antipathetic variations in Sr and Mg in studied natural speleothems, implies that intracrystalline zoning phenomena, if present, are on a finer scale in those natural materials compared with experimental products

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