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Enviroscan Ukrainian Institute of Speleology and Karstology

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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 sorption is 1. a general term used to encompass the process of absorption and adsorption [22]. 2. all processes which remove solutes from the fluid phase and concentrate then on the solid phase of the medium [22].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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What is Karstbase?



Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for hierarchy (Keyword) returned 15 results for the whole karstbase:
Showing 1 to 15 of 15
The Hydrology of a Glacierised Alpine Karst Castlegaurd Mountain, Alberta, PhD Thesis, 1983,
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Smart, Charles Christopher

Alpine karst throughout the world has been affected by past glaciation, and yet little is known of the interactions between glacier ice and karst. This dissertation attempts to gain some understanding of the problem through the study of the Castleguard Area, Alberta, where a karst aquifer is presently overlain by temperate glacier ice.
Quantitative fluorometric tracing and hydrometric measurements generated a broad data base on aquifer behaviour. Tracer breakthrough curves were interpreted using a new systematic approach which considers an explicit set of processes likely to affect the particular tracer under the given experimental conditions. Non-linearity in aquifer behaviour and rapid groundwater velocities demonstrated the aquifer to be an extreme conduit type Conduit springs are elements in a vertical hierarchy in which the topmost springs are "overflows" and exhibit greater flow variability than their associated "underflows". A numerical model was developed to simulate a conduit aquifer. It demonstrated that pulse train and recession analysis widely accepted methods of karst aquifer investigation, could be rather misleading when applied to conduit aquifers.
Interactions between ice and groundwater were observed at two scales: regulation water appeared to feed a diffuse percolation system and supraglacial melt passed into subglacial conduits which entered open vadose shafts. Karst is unlikely to be entirely subglacial in origin because of the limited aggressiveness of subglacial waters.
The Castlegaurd karst appeared to have originated preglacially in response to the breaching of impermeable caprock. Glaciation re-ordered the landscape and produced abundant clastic debris which subsequently blocked or obstructed karst conduits. Much of the resulting karst is paragenetic and comparatively immature due to glacial disruption and slow growth rates. Geomorphic and hydrologic interactions between ice and karst depend intimately upon the relationship between the geographic zones of the glacier and the aquifer.

Structures des aquifres carbonats d'aprs les donnes de captages d'eau, 1984,
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Pulidobosch A. , Castillo E.
STRUCTURE OF CARBONATE AQUIFERS IN EASTERN SPAIN FROM THE DATA DERIVED FROM WELLS - From a statistical analysis of the data from several wells, pumping the carbonate materials of Creu Formation (Cenomanian-Senonian), in an area in Eastern Spain, it can be deduced that the yield and specific capacity fits well to a log-normal theoretical distribution. The biggest capacity of the wells located in discharge areas respect to the wells situated in recharge areas is interpreted as a result of the "hierarchical" role of karstification processes.

Karst hydrogeology of the Canadian Rocky Mountains, PhD Thesis, 1991,
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Worthington, Stephen Richard Hurst

An analysis of the discharge and hydrochemical variations of contrasting springs at Crowsnest Pass showed they were part of a vertical hierarchy in the aquifer, in which underflow and overflow components play a dominant role. It was found that karst springs at Crowsnest Pass and elsewhere show a range between two end members. Thermal springs have long, deep flow paths, with high sulphate concentrations, low discharge variance and low flow velocities. Overflow springs have local shallow flow paths, low sulphate, high discharge variance, and high flow velocities. Intermediate between these end members are underflow springs; in the Rocky Mountains these are mostly aggraded, and give the sustained winter flow and high sulphate concentrations found in major rivers. It was found that underflow or overflow behaviour is able to explain most of the contrasts found between karst springs in discharge and sulphate concentrations. Conversely, differences in bicarbonate concentration are principally due to the ratio of allogenic to autogenic recharge to the aquifer. Hydraulic analysis showed that gradients decrease in the downstream direction, and are typically 0.0001-0.05 at maximum discharges, that friction factors vary by a factor of $>$1000, and that most active conduits have closed-channel flow and are in dynamic equilibrium with sediment supply. The analysis of the hydrological data from Crowsnest Pass and elsewhere has led to the development of a new conceptual model for groundwater flow in karst, in which the Hagen-Poiseuille flow net conditions the aquifer for conduit development, and determines where the conduits will be. The model explains why most conduits are in dynamic equilibrium with sediment supply, why temperate karst springs are mostly vauclusian, what the mean time for speleogenesis is, how $>$98% of the solution of limestone is in the surficial zone, and why there are karstic hot springs in the Rocky Mountains and elsewhere. The model enables predictions to be made of sink to resurgence flow velocities, of conduit depth below the water table, of the ratio of beds to joints used by conduits, of the spacing between cave tiers, and of the depth of vauclusian springs. This new understanding of how karstic aquifers develop and function gives a powerful predictive ability to karst hydrogeology.

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Dehon Ra,
Hrad Vallis is located in the transition zone between Elysium Mons and Utopia Planitia. Near its origin, at the northern edge of Elysium lavas, Hrad Vallis is characterized by a low-sinuousity channel within a north-northwest-trending, broad, flat-floored valley. A nearby flat-floored valley is parallel to the Hrad trend and parallel to elongate depressions, fissures, and faults in the region. An apparent hierarchy of landforms provides insight into the origin of the features associated with Hrad Vallis. The sequence leading to the development of Hrad Vallis consists of the following (1) formation of isolated depressions as either karst depressions or thermokarst valleys along faults and fissures in response to circulating ground water; (2) expansion of depressions along structural trends to coalesce as composite valleys, and (3) incision of a channel on the floor of Hrad valley by continued discharge of water from the subsurface after its initial formation by nonfluvial processes. Mud flows, polygonally fractured terrain, and chaotic terrain near the head of the major valleys suggest thixotropic behavior of saturated, clay-rich materials. An extended period of time is indicated during which freely circulating water existed on id beneath the surface of Mars. Karst and thermokarst processes imply very different climatic regimes and different host materials. The presence of karst topography implies extensive deposition of carbonates or other soluble rocks, whereas the presence of thermokarst basins implies the existence of porous, water/ice-saturated clastic or volcaniclastic materials

High-resolution sequence stratigraphic correlation in the Upper Jurassic (Kimmeridgian)-Upper Cretaceous (Cenomanian) peritidal carbonate deposits (Western Taurides, Turkey), 1999,
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Altiner D, Yilmaz Io, Ozgul N, Akcar N, Bayazitoglu M, Gaziulusoy Ze,
Upper Jurassic (Kimmeridgian)- Upper Cretaceous (Cenomanian) inner platform carbonates in the Western Taurides are composed of metre-scale upward-shallowing cyclic deposits (parasequences) and important karstic surfaces capping some of the cycles. Peritidal cycles (shallow subtidal facies capped by tidal-Aat laminites or fenestrate limestones) are regressive- and transgressive-prone (upward-deepening followed by upward-shallowing facies trends). Subtidal cycles are of two types and indicate incomplete shallowing. Submerged subtidal cycles are composed of deeper subtidal facies overlain by shallow subtidal facies. Exposed subtidal cycles consist of deeper subtidal facies overlain by shallow subtidal facies that are capped by features indicative of prolonged subaerial exposure. Subtidal facies occur characteristically in the Jurassic, while peritidal cycles are typical for the Lower Cretaceous of the region. Within the foraminiferal and dasyclad algal biostratigraphic framework, four karst breccia levels are recognized as the boundaries of major second-order cycles, introduced for the first time in this study. These levels correspond to the Kimmeridgian-Portlandian boundary, mid-Early Valanginian, mid-Early Aptian and mid-Cenomanian and represent important sea level falls which affected the distribution of foraminiferal fauna and dasyclad flora of the Taurus carbonate platform. Within the Kimmeridgian-Cenomanian interval 26 third-order sequences (types and 2) are recognized. These sequences are the records of eustatic sea level fluctuations rather than the records of local tectonic events because the boundaries of the sequences representing 1-4 Ma intervals are correlative with global sea level falls. Third-order sequences and metre-scale cyclic deposits are the major units used for long-distance, high-resolution sequence stratigraphic correlation in the Western Taurides. Metre-scale cyclic deposits (parasequences) in the Cretaceous show genetical stacking patterns within third-order sequences and correspond to fourth-order sequences representing 100-200 ka. These cycles are possibly the E2 signal (126 ka) of the orbital eccentricity cycles of the Milankovitch band. The slight deviation of values, calculated for parasequences. from the mean value of eccentricity cycles can be explained by the currently imprecise geochronology established in the Cretaceous and missed sea level oscillations when the platform lay above fluctuating sea level. Copyright (C) 1999 John Wiley & Sons, Ltd

Hydrogeologic control of cave patterns, 2000,
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Palmer A. N.
Cave patterns are controlled by a hierarchy of hydrogeologic factors. The location and overall trend of a cave depends on the distribution of recharge and discharge points within the karst aquifer. Specific cave patterns, i.e. branchwork vs. maze patterns, are controlled mainly by the nature of the groundwater recharge. Individual passage configurations are determined by the structural nature of the bedrock and by the geomorphic evolution of the aquifer. The origin of branchwork caves is favored by point recharge sources of limited catchment area. Floodwater recharge, especially through sinking streams, tends to produce maze caves or local mazes superimposed on branchwork caves. Through floodwater activity, anastomotic mazes form in prominently bedded aquifers, network mazes in prominently fractured aquifers, and spongework mazes in highly porous or brecciated rocks. Epikarst, network caves, and spongework caves are also produced by diffuse or dispersed infiltration into the karst aquifer, and network and spongework caves can be the product of mixing of two waters of contrasting chemistry. Ramiform caves are produced most often by rising water rich in hydrogen sulfide, which oxidizes to sulfuric acid. Deep-seated processes that help to initiate cave development include the interaction between carbonates and sulfates, which can greatly increase the solubility of dolomite, gypsum, and anhydrite, while calcite precipitates. Although tightly confined artesian conditions have long been associated with the origin of maze caves, they actually have no inherent tendency to form mazes. The slow movement of groundwater close to equilibrium with dissolved bedrock, typical of tightly confined artesian aquifers, is the least favorable setting for maze development.

Quantification of Macroscopic Subaerial Exposure Features in Carbonate Rocks, 2002,
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Budd Da, Gaswirth Sb, Oliver Wl,
The macroscopic features that characterize subaerial exposure surfaces in carbonates are well known, but their significance has not been quantitatively evaluated. This study presents such an analysis in the lower Oligocene Suwannee Limestone of west-central Florida. Eleven cores were point counted on a foot-by-foot basis for the abundance of caliche, rhizoliths, karst breccia, open vugs, infiltrated sediment, fractures, and pedogenic alteration. These features occur at and below intraformational exposure surfaces, which represent hiatuses estimated at 104 to 105 years, and an uppermost sequence-bounding unconformity representing 0.5 Myr, as revealed by Sr-isotope data. Statistical analyses of the point-count data reveal only a few significant relationships. (1) The hierarchy of exposure surfaces, and by inference duration of exposure, is differentiated only at a marginally significant level by sediment-filled vugs preferentially associated with the sequence boundary. Duration of exposure did not have a significant impact on the relative abundance of all other features. (2) Proximity (< 5 ft; 1.5 m) to any exposure surface is indicated only by rhizoliths, caliche, and pedogenic alteration, whereas karst breccia is preferentially found distal (> 5 ft) to both types of surfaces. Fractures, open vugs, and infiltrated sediment show no proximal or distal preference for either type of surface. (3) Depositional texture has no statistically significant affect on the presence or abundance of the exposure features, with the exception that rhizoliths and open vugs are preferentially more abundant in packstones relative to grainstones. This is interpreted to be the result of a soil-moisture effect. Factor analysis defines four factors that explain 46% to 52% of the total variance in the abundance data relative to the sequence boundary and the intraformational surfaces, respectively. The loading of each exposure feature on each factor is the same with respect to both types of surfaces, which is further evidence that the abundance of exposure features is independent of duration of exposure. Factor 1 is interpreted to be the amplitude of base-level changes and controls the abundance of karst breccia. Factor 2 is interpreted to be abundance of vegetation and relates to the abundance of rhizoliths and fractures. Factor 3 is interpreted to be a combination of soil-zone PCO2 and the availability of water and affects the abundance of pedogenic overprinting, caliche, and open vugs. Factor 4 is stratigraphic proximity to the sequence boundary, which controls the presence of sediment-filled voids. The amount of uncorrelated unique variance associated with infiltrated sediments, pedogenic overprinting, caliche, and open vugs is large (> 60%), meaning that feature abundance is also influenced by other unidentified site-specific factors. These results demonstrate that quantifying the abundance of macroscopic subaerial exposure features in limestones has the potential to yield more insight into the significance of those features than a mere qualitative assessment. This is particularly true when assessing the potential role of the many variables that can affect the development of these features

How speleothems grow: An introduction to the ontogeny of cave minerals, 2003,
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Self, C. A. , Hill, C. A.
Speleothems are secondary mineral deposits whose growth in caves can be studied by mineralogic techniques. One of these techniques is the ontogeny of minerals, which is the study of individual crystals and their aggregates as physical bodies rather than as mineral species. Ontogeny of cave minerals as a scientific subject has been developed in Russia but is poorly understood in the West. This paper introduces the basic principles of this subject and explains a hierarchy scheme whereby mineral bodies can be studied as crystal individuals, aggregates of individuals, associations of aggregates (termed koras), and as sequences of koras (ensembles).

An approach to the multi-element and multi-scale classification of the Limestone Pavement environment of Hutton Roof and Farleton Fell, Cumbria, UK, 2004,
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Huxter, Eric Andrew

 Limestone Pavements are highly significant components of the physiographic and ecological landscapes of the UK. As relict glacial features they are subject to destruction by natural processes but also by human intervention. This thesis identifies the most effective methods to monitor such change at a variety of temporal and spatial scales, based on the Morecambe Bay pavements at Hutton Roof and Farleton Fell. The starting point for such a study is a methodology to define the baseline on which to base change detection and the key to this is the development of a suitably detailed scene model. This must reflect the environment at the macro-, meso- and micro- scales and also incorporate considerations of the dynamics involved in the landscape evolution. The scene model (the Land Surface Classification Hierarchy (LSCH)) was developed by field measurement of the reflectance spectra of the main elements, biotic and abiotic, with measurements of the pavement surface in terms of the scale of karren development and the texture of the limestone itself. Study of the DEM allowed a fractal dimension to be established and also the nature of ice-flow and its contribution to pavement development, with extending flow, entraining fractured limestone blocks above a plastic, impermeable shale band, being the main mechanism. At the meso scale pavements were classified according to clint form derived from intra-pavement trends in grike direction calculated by Preferred Direction Analysis. Measurements of the key karren forms, runnels, solution pits and pipes and grikes allow assessment of their contribution to the variability of the pavement surface as an element of the scene model through the identification of solution domains. Identification of different lithologies allowed an investigation of spatial variation across the study area, although lithological control on karren form and magnitude is weaker than variability from age of exposure as shown by statistical analysis of karren morphometry using univariate comparative methods and Link diagrams, bivariate and multivariate regression, discriminant analysis, cluster analysis, multi-dimensional scaling and star diagrams with the derived Star Index. Pavements were classified according to karren morphometry. The traditional view of pedestals as an indicator of solution rates, and hence the concentration of solution at the surface, is challenged through the investigation of water flow over the pavement surface and the consideration of the role of lichen as a protective agent as well as the size of solution pits and grike width. It is suggested that only 10% of solution potential is achieved at the surface with 43% in the immediate epikarst. From this solution rate diagrams were developed, allowing the dating of exposure of pavements. These were shown to be within the period when human impact in the area was becoming significant and confirms an early anthropogenic impact on this element of the landscape. Further to this the development of grikes as emergent features was confirmed and this linked to the concept of breakthrough, allowing a model of grike development to be proposed, an important consideration in the dynamics of pavement change. At the micro scale texture analysis allowed the calculation of fractal measures which are related to variations in reflectance. The radiometric response of biotic and abiotic elements of the scene model was analysed confirming the facility of the baseline scene reflectance model of the pavement. Remotely sensed images from the Airborne Digital Camera were linked to ATM, CASI and TM images assessing the effect of scale on change detection and the evaluation of the pavement environment.

Suitability Assessment for New Minia City, Egypt: A GIS Approach to Engineering Geology, 2005,
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Aly Mh, Giardino Jr, Klein Ag,
Urban development is a high priority in Egypt. New Minia City, located on the eastern bank of the Nile River, approximately 250 km south of Cairo, is one of 16 new development communities. Urban development in New Minia City may encounter several geo-environmental problems. Karst conditions and structural features in the local heterogeneous bedrock limit its suitability for constructional purposes. In this research, suitability of the area for urban development was assessed using a geographic information systems (GIS)-based approach. A weighted GIS model that incorporated land use/cover, types of soil, karst feature distribution, fracture densities, slopes, distances to major faults and streams, road network, and city boundaries was established to create a map of site suitability for the city. Model weights were developed using the analytical hierarchy process (AHP) approach. Current urban land use within New Minia City falls into four classes of suitability. Approximately 7 percent of the area built by 2002 is in the low suitability class, which suggests that the map of site suitability can serve as a reliable base for planning sustainable development in New Minia City. The developed map of site suitability is effective for assessing and revealing ratings of suitability for urban development. Furthermore, the map of suitability provides the foundation for informed decision making in the development of New Minia City

Processes of Speleogenesis: a Modeling Approach, 2005,
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Dreybrodt W. Gabrovsek F. , Romanov D.

This book draws together the major recent advances in the modeling of karst systems. Based on the dissolution kinetics of limestone, and flow and transport processes in its fractures, it presents a hierarchy of cave genetic situations that range from the enlargement of a single fracture to the evolution of cavernous drainage patterns in confined and unconfined karst aquifers. These results are also applied to the evolution of leakage below dam sites in karst. The book offers a wealth of information that helps to understand the development of cave systems. It addresses geologists, hydrologists, geomorphologists, and geographers. It is also of interest to all scientists and engineers who have responsibilities for groundwater exploration and management in karst terrains.

?Processes of Speleogenesis: a Modeling Approach is an exciting book that brings together and displays the products of the first and second generations of karst cave and aquifer computer modeling in a succinct fashion, with excellent illustrations and stimulating contrasts of approach. It is a ?benchmark? publication that all who are interested in speleogenesis should read. It will be a very useful volume for teaching, not only in karst and hydrogeology, but for others who use computer modeling in the physical and spatial sciences.? (From the foreword by D.C. Ford)

?This book is an extraordinary achievement that warrants close attention by anyone interested in speleogenesis??This book is ideal for researchers in speleogenesis who have a solid grasp in technical aspects. Most of the necessary background information is outlined in the first chapter, but subtle aspects will be clear only to those who already have a good background in geochemistry and computer modeling especially when interpreting the figures. This book is not aimed at groundwater hydrologists, although the results would be eye-opening to anyone in that field who denies the importance of solution conduits in carbonate aquifers.? (From book review by A.N. Palmer, JCKS, Volume 67, No.3, 2005)

?To specialists the book is very helpful and and up-to-date, providing many ideas and answering many questions.? (From book review by P. Hauselmann, Die Hohle, Volume 56, 2005)


  1. Introduction
  2. Equilibrium chemistry and dissolution kinetics of limestone in H2O-CO2 solutions
  3. The evolution of a single fracture
  4. Modeling karst evolution on two-dimensional networks: constant head boundary conditions
  5. Unconfined aquifers under various boundary conditions
  6. Karstification below dam sites
  7. Conclusion and future perspectives
  8. Bibliography

GUEST CHAPTER by Sebastian Bauer, Steffen Birk, Rudolf Liedl and Martin Sauter
Simulation of karst aquifer genesis using a double permeability approach investigation for confined and unconfined settings

GUEST CHAPTER by Georg Kaufmann
Structure and evolution of karst aquifers: a finite-element numerical modeling approach

From soil to cave: Transport of trace metals by natural organic matter in karst dripwaters, 2012,
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Hartland A. , Fairchild I. J. , Lead J. R. , Borsato A. , Baker A. , Frisia S. , Baalousha M.

This paper aims to establish evidence for the widespread existence of metal binding and transport by natural organic matter (NOM) in karst dripwaters, the imprint of which in speleothems may have important climatic significance. We studied the concentration of trace metals and organic carbon (OC) in sequentially filtered dripwaters and soil leachates from three contrasting sites: Poole's Cavern (Derbyshire, UK), Lower Balls Green Mine (Gloucestershire, UK) and Grotta di Ernesto (Trentino, Italy). The size-distribution of metals in the three soils was highly similar, but distinct from that found in fractionated dripwaters: surface-reactive metals were concentrated in the coarse fraction (>100 nm) of soils, but in the fine colloidal (b100 nm) and nominally dissolved (b1 nm) fractions of dripwaters. The concentration of Cu, Ni and Co in dripwater samples across all sites were well correlated (R2=0.84 and 0.70, Cu vs. Ni, Cu vs. Co, respectively), indicating a common association. Furthermore, metal ratios (Cu:Ni, Cu:Co) were consistent with NICA-Donnan n1 humic binding affinity ratios for these metals, consistent with a competitive hierarchy of binding affinity (Cu>Ni>Co) for sites in colloidal or dissolved NOM. Large shifts in Cu:Ni in dripwaters coincided with high fluxes of particulate OC (following peak infiltration) and showed increased similarity to ratios in soils, diagnostic of qualitative changes in NOMsupply (i.e. fresh inputs of more aromatic/hydrophobic soil organic matter (SOM) with Cu outcompeting Ni for suitable binding sites). Results indicate that at high-flows (i.e. where fracture-fed flow dominates) particulates and colloids migrate at similar rates, whereas, in slow seepage-flow dripwaters, particulates (>1 μm) and small colloids (1–100 nm) decouple, resulting in two distinct modes of NOM–metal transport: high-flux and low-flux. At the hyperalkaline drip site PE1 (in Poole's Cavern), high-fluxes of metals (Cu, Ni, Zn, Ti, Mn, Fe) and particulate NOM occurred in rapid, short-lived pulses following peak infiltration events, whereas low-fluxes of metals (Co and V>Cu, Ni and Ti) and fluorescent NOM (b ca. 100 nm) were offset from infiltration events, probably because small organic colloids (1–100 nm) and solutes (b1 nm) were slower to migate through the porous matrix than particulates. These results demonstrate the widespread occurrence of both colloidal and particulate NOM–metal transport in cave dripwaters and the importance of karst hydrology in affecting the breakthrough times of different species. Constraints imposed by soil processes (colloid/particle release), direct contributions of metals and NOM from rainfall, and flow-routing (colloid/particle migration) are expected to determine the strength of correlations between NOM-transported metals in speleothems and climatic signals. Changes in trace metal ratios (e.g. Cu:Ni) in speleothems may encode information on NOMcomposition, potentially aiding in targeting of compound-specific investigations and for the assessment of changes in the quality of soil organic matter.

Speleothem microstructure/speleothem ontogeny: a review of Western contributions, 2012,
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White William B.

Mineral ontogeny is the study of the growth and development of mineral deposits in general and, in the present context, speleothems in particular. Previous researchers, mainly in Russia, have developed a nomenclatural hierarchy based on the forms and habits of individual crystals and the assembly of individual crystals into both monomineralic and polymineralic aggegates (i.e. speleothems). Although investigations of the growth processes of speleothems are sparse, there is a large literature on growth processes of speleothem minerals and related crystals in the geochemical and materials science literature. The purpose of the present paper is to sort through the various concepts of crystal growth and attempt to relate these to observations on speleothems and to the Russian conceptual framework of mineral ontogeny. For calcite, the most common mineral in speleothems, the activation energy for two dimensional nucleation (required for the growth of large single crystals) is almost the same as the activation energy for three- dimensional nucleation (which would result in the growth of many small crystals). Calcite growth is highly sensitive to minor impurities that may poison growth in certain crystallographic directions or may poison growth altogether. Extensive recent research using the atomic force microscope (AFM) provides many details of calcite growth including the transition from growth on screw dislocations to growth by two-dimensional nucleation. The deposition of aragonite speleothems requires metastable supersaturation curve and is usually ascribed to the impurities Mg2+ and Sr2+. AFM studies reveal that Mg2+ poisons calcite growth by blocking deposition sites on dislocations, thus allowing supersaturation to build up past the aragonite solubility curve. Sr2+ precipitates as a Sr-rich nucleus with the aragonite structure which acts as a template for aragonite growth. The different morphology of gypsum speleothems can be explained by the different growth habit of gypsum. Examples of twinned growth, dendrite growth, and spherulitic growth are common in the crystal growth literature and can be used to interpret the corresponding cave forms. Interpretation of monomineralic aggregate growth follows from individual crystal mechanisms. Interpretation of polymineralic aggregate growth requires knowing the evolving chemistry which in turn requires new methods for the sampling and analysis of microliter or nanoliter quantities of fluid.

Characterization of the vadose flow and its influence on the functioning of karst springs: Case study of the karst system near Postojna, Slovenia , 2012,
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Kogovek Janja, Petrič, Metka

In three selected drips in the Postojna cave in SWw Slovenia and in the nearby Korentan spring, which in general belongs to the same karst aquifer, the discharge and electrical conductivity were measured at 15-minute intervals. Simultaneously, the meteorological parameters in Postojna were measured and the effective infiltration was assessed. The data obtained in the period of one hydrological year, 2003–2004, was compared in order to study the influence of the vadose flow on the characteristics of groundwater flow in a karst system and on the functioning of a karst spring. The highest discharges of the Korentan spring are the result of the inflow of water through a hierarchy of fissures of various permeabilities within the vadose zone, but the contribution of stored water from low-permeability zones is especially important. One of our most significant findings is that in the conditions of high saturation of the vadose zone, the network of small fissures is hydraulically connected, which enables an integral reaction of the system to the pressure pulse induced by infiltrated precipitation. On the other hand, a detailed comparison of effective infiltration and discharge indicates that in dry periods with a lower saturation of the vadose zone, the infiltrated precipitation is mainly stored in the system and only the most permeable fissures enable a rapid transfer of the recharge impulses toward the spring. Data on measured discharge and conductivity were additionally compared in order to study the complex conditions of the actual mass flow of water through the system.

Karst hierarchical flow systems in the Western Cordillera of North America, 2013,
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Ford, Derek

By definition, karstic flow systems are networks of solutional conduits. Their spatial patterns and hierarchical organisation are strongly affected by differing lithology and geologic structure, and by the location and modes of recharge – unconfined, confined, interformational. For purposes of discussion, this paper will review six examples rang-ing across platform and reefal limestones and dolostones, dolostone breccias, gypsum and salt, in widely differing structural, geomorphic and hydrologic settings: (1) The Carcajou River karst at Lat. 65° N in the Mackenzie Mountains, where leaky permafrost superimposes a frozen ground hierarchy on those due to lithology, structure and topog-raphy: (2) The S Nahanni River karst at Lat. 62° N, with an intrusive-derived local thermal system and lengthy, strike-oriented meteoric flow systems that contribute to an outlet H2S thermal system at the basin topographic low: (3) Castleguard Mountain Karst (Lat. 52° N) in massive Main Ranges structures of the Rocky Mountains, with a complex alpine hierarchy of base-flow and overflow springs: (4) Crowsnest Pass, in steep thrust structures in the Rocky Mountain Front Ranges, where regional strike-oriented flow systems extending between Lats. 49° and 50° N and paired above and below a major aquitard have been disaggregated by glacial cirque incision: (5) The Black Hills geologic dome at Lat. 44° N in South Dakota, USA, with a sequence of hot springs at low points around the perimeter, discharging through sandstones but with some of the world’s most extensive hypogene maze caves formed in a limestone karst barré setting behind them: (6) The Sierra de El Abra, at Lat. 23° N in Mexico, a deep and lengthy (100 km) reef-backreef limestone range being progressively exposed and karstified by stripping of a cover of clastic rocks; the springs are few but amongst the largest known in karst anywhere, located at the northern and southern low extremities along the strike of the reef, plus breaches (windows) in the cover further south.

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