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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 insectivore is an animal that feeds on insects. almost all species of north american bats are insectivores [23]. see also carnivore; herbivore; omnivore.?

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


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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;
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Your search for magnitude (Keyword) returned 147 results for the whole karstbase:
Showing 121 to 135 of 147
Honshu, Japan Earthquake of March 11, 2011 9.0 Magnitude recorded in the Edwards Aquifer, San Antonio, Texas, 2011,
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Schindel, Geary M.

The Edwards Aquifer is a large karst aquifer located in south-central Texas USA. The Index Well J-17, in which water levels in the aquifer are continuously monitored since 1934, detected distinctly the March 11, 2011 Honshu, Japan earthquake (9.0 magnitude). The Edwards Aquifer fluctuated approximately 0.3 meters (1 foot) during the initial response and continued to oscillate for approximately two hours after the event.


Demonstrating Interconnection Between a Wastewater Application Facility and a First Magnitude Spring in a Karstic Watershed: Tracer Study of the Tallahassee, Florida Treated Effluent Spray Field 2006-2007, 2011,
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Kincaid Todd R. , Davies Gareth J. , Werner Christopher L. , Dehan Rodney S.

Interconnection of the Trinity (Glen Rose) and Edwards Aquifers along the Balcones Fault Zone and Related Topics, 2011,
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The proceedings volume contains nine contributions presented during the Karst Conservation Initiative Meeting held in February 17, 2011 at The University of Texas at Austin.

The Edwards and Trinity Aquifers are critical water resources, supplying high-quality potable water to over two million people in the greater Austin-San Antonio region of central Texas, USA. These Cretaceous carbonate aquifers are hydrogeologically juxtaposed by extensive Miocene tectonic deformation associated with the Balcones Fault Zone, where the younger Edwards Group limestone has been downthrown relative to the older Trinity Group. The karstic aquifers are managed separately by regional water regulatory entities, and they have been historically treated as independent systems, both scientifically and from a water policy standpoint. Recent awareness of a significant interconnection between the Edwards and Trinity Aquifers has resulted in a number of hydrogeologic investigations documenting how they may actually operate as a single system. Studies related to upland recharge variability (spatial and temporal), stream loss, phreatic dye tracing, multi-port well monitoring, geochemistry, biologic habitat analysis, geophysics, and groundwater modeling indicate that the two are much less separated than previously observed. Summaries of these investigations conclude that changes in management strategies may be required to properly protect the quantity and quality of water in the Edwards and Trinity Aquifers.

Contents (click to open individual articles)

Introduction and Acknowledgements 

I nterconnection of the Edwards and Trinity Aquifers, Central Texas, U.S.A. 
Marcus O. Gary 

Spatial and Temporal Recharge Variability Related to Groundwater Interconnection of the Edwards and Trinity Aquifers, Camp Bullis, Bexar and Comal Counties, Texas 
Marcus O.Gary, George Veni, Beverly Shade, and Robin Gary

Potential for Vertical Flow Between the Edwards and Trinity Aquifer, Barton Springs Segment of the Edwards Aquifer 
Brian A. Smith and Brian B. Hunt

Could Much of Edwards Aquifer “Matrix Storage” Actually be Trinity Aquifer Contributions from the Blanco River? 
Nico M. Hauwert

Geophysical Correlation of Haby Crossing Fault (Medina County) and Mt. Bonnell Fault (Travis County) and Their Implications on T-E Interconnection 
Mustafa Saribudak

Edwards Aquifer – Upper Glen Rose Aquifer Hydraulic Interaction 
R.T. Green, F.P. Bertetti, and M.O. Candelario

Interaction Between the Hill Country Portion of the Trinity and Edwards Aquifers: Model Results 
Ian C. Jones

Using Tracer Testing Data for Resource Management Planning 
Geary Schindel and Steve Johnson

Demonstrating Interconnection Between a Wastewater Application Facility and a First Magnitude Spring in a Karstic Watershed: Tracer Study of the Tallahassee, Florida Treated Effluent Spray Field 2006-2007  
Todd R. Kincaid, Gareth J. Davies, Christopher L. Werner, and Rodney S. DeHan

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The visitors influence on air temperature of Yaltinskaya and Geofizicheskaya show caves (Ay-Petri massif, Mount Crimea), 2011,
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Amelichev, G. N. , Tokarev, S. V. , Klimchouk, A. B.

Monitoring of air temperature in the Yaltinskaya and Geofizicheskaya caves, situated in the Ay-Petri massif in the Mountainous Crimea, was conducted during 7 months. The purpose of this study is to determine the visitors’ influence on natural environment of the caves. Average temperature during the period of monitoring in Yaltinskaya cave was 7,55 °  (v=0,01) and in Geophisicheskaya cave was 6,99 °(v=0,06).

The visitation by tourists causes rising of air temperature up to 0,39 ˚per day. In periods of low visitation the anthropogenic thermal anomalies broke down naturally during the night time, with the participation of processes of evaporation and condensation of cave moisture. In periods of high attendance a partial retention and accumulation of anthropogenic heat occurs. Daily thermal anomalies in starting and finishing periods of holiday season were at the average 0,04 ˚(Yaltinskaya) and 0,13 ˚(Geofizicheskaya). In the peak season they were 0,07 and 0,20 °, respectively.

The anthropogenic influence on the temperature of the studied caves has a seasonal character. It is unstable and is 1-2 orders of magnitude less than the seasonal variability of the natural temperature background.


Integrating geomorphological mapping, trenching, InSAR and GPR for the identification and characterization of sinkholes: A review and application in the mantled evaporite karst of the Ebro Valley (NE Spain), 2011,
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Gutié, Rrez Francisco, Galve Jorge Pedro, Lucha Pedro, Castañ, Eda Carmen, Bonachea Jaime, Guerrero Jesú, S

This contribution illustrates the advantages of integrating conventional geomorphological methods with InSAR, ground penetrating radar and trenching for sinkhole mapping and characterization in a mantled evaporite karst area, where a significant proportion of the karstic depressions have been obliterated by artificial fills. The main practical aim of the investigation was to elucidate whether buried sinkholes overlap the areas planned for the construction of buildings and services, in order to apply a preventive planning strategy. Old aerial photographs and detailed topographic maps were the most useful sources of information for the identification of sinkholes and helped to obtain information on their chronology, either a minimum age or bracketing dates. The InSAR technique provided subsidence rate values ranging from 4.4 to 17.3 mm/yr consistent with the spatial distribution of the mapped sinkholes. This quantitative deformation data helped corroborating independently the existence of active buried sinkholes and improving the delineation of their limits. The GPR profiles contributed to the precise location of sinkhole edges, provided information on the geometry of buried sinkholes and deformation structures and helped to site trenches and to rule out the existence of sinkholes in particular areas. The main input derived from the trenches includes: (1) Confirming or ruling out anomalies of the GPR profiles attributable to subsidence. (2) Precise location of the edge of some filled sinkholes. (3) Information on subsidence mechanisms recorded by various deformation structures and cumulative subsidence magnitude. (4) Calculating minimum long-term subsidence rates using radiocarbon dates obtained from deformed sinkhole deposits. (5) Unequivocal evidence of active subsidence in areas assigned for the construction of buildings


Improving sinkhole hazard models incorporating magnitudefrequency relationships and nearest neighbor analysis, 2011,
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Galve Jorge P. , Remondo Juan, Gutié, Rrez Francisco

This work presents a methodology for elaborating sinkhole hazard models that incorporate the magnitude and frequency relationships of the subsidence process. The proposed approach has been tested in a sector of the Ebro valley mantled evaporite karst, where sinkholes, largely induced by irrigation practices, have a very high occurrence rate (>50 sinkholes/km2/yr). In this area, covering 10 km2, a total of 943 new cover collapse sinkholes were inventoried in 2005 and 2006. Multiple susceptibility models have been generated analyzing the statistical relationships between the 2005 sinkholes and different sets of variables, including the nearest sinkhole distance. The quantitative evaluation of the prediction capability of these models using the 2006 sinkhole population has allowed the identification of the method and variables that produce the most reliable predictions. The incorporation of the indirect variable nearest sinkhole distance has contributed significantly to increase the quality of the models, despite simplifying the modeling process by using categorical rather than continuous variables. The best susceptibility model, generated with the total sinkhole population and the selected method and variables, has been transformed into a hazard model that provides minimum estimates of the spatial–temporal probability of each pixel to be affected by sinkholes of different diameter ranges. This transformation has been carried out combining two equations derived from the more complete 2006 sinkhole population; one of them expressing the expected spatial–temporal probability of sinkhole occurrence and the other the empirical magnitude and frequency relationships generated for two different types of land surfaces, which control the strength of the surface layer and the size of the sinkholes. The presented method could be applied to predict the spatial–temporal probability of events with different magnitudes related to other geomorphic processes (e.g. landslides).


Modelling of slope processes on karst , 2011,
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Stepinik Uro, Kosec Gregor

The present paper is concerned with the modelling of the karst slope processes. A simple straightforward one dimensional physical model is introduced in order to assess basic behaviour of the slope development. The model takes in account mass continuity of weathered material, the mechanical and chemical weathering of the bedrock. The paper focuses on the slope formation
with respect to the ratios between different magnitudes of governing processes (mechanical and chemical weathering and mass movement). The introduced approach representsa first step in understanding slope processes and does not pose a realistic quantitative comparison with field measurements. However, the results gathered with the model show good qualitative
agreement with the field observations. Three different representative cases are studied: dominant mechanical weathering
case, balanced mechanical and chemical weathering case and dominant chemical weathering case.


Development of a Specific Quantitative Real-Time PCR Assay to Monitor Chlorella DNA: A Case Study from Mammoth Cave National Park, Kentucky, USA , 2011,
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Fowler, Richard F.

Estimates of phytoplankton abundance are important parameters
watched by stewards of water quality and freshwater ecology in rivers, streams, and reservoirs. A targeted phytoplankton assay
for Chlorella DNA was developed to estimate the abundance of the predominant species of green algae in surface waters of Mammoth Cave National Park (MACA) in Kentucky, USA. The phytoplankton community in the Green River in MACA has been shown to consist of 95% Chlorella sp. (Wullschlegger et al., 2003). Chlorella 18S rRNA gene sequences were amplified and quantified using Quantitative Real-Time PCR (qPCR) with primers
specific for the family Chlorellaceae in the class Trebouxiophyceae,
order Chlorellales. Concentrations of Chlorella DNA in river water samples were measured by comparison to a standard curve generated by DNA extracted from a live laboratory culture of C. vulgaris. DNA isolated from other sources including bacteria,
amoebae, fungi, decapods, insects, cave sediment, and a different
green alga, Chlamydomonas, produced no PCR products and thus did not interfere with the detection and quantification of Chlorella DNA. The assay proved quantitative over more than four orders of magnitude with a method detection limit (MDL) of approximately 2.3 x104 cells/L. Presence or absence of Chlorella
DNA could be demonstrated at concentrations ten to 100 times lower than the calculated MDL. Chlorella was detected in lampenflora samples from three tourist trails, and Chlorella was absent from sediment samples off tourist trails that were known to contain high concentrations of bacterial DNA. Demonstration of the utility of the technique was illustrated by a case study in Mammoth Cave National Park to determine Chlorella concentrations
at various sampling sites of karst surface streams where invasive zebra mussels are a threat to native species.


From sink to resurgence: the buffering capacity of a cave system in the Tongass national forest, USA , 2011,
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Hendrickson Melissa R. , Groves Chris

The Tongass National Forest of Southeast Alaska, USA, pro­vides a unique environment for monitoring the impact of the cave system on water quality and biological productivity. The accretionary terrane setting of the area has developed into a complex and heterogeneous geologic landscape which includes numerous blocks of limestone with intense karstification. Dur­ing the Wisconsian glaciation, there were areas of compacted glacial sediments and silts deposited over the bedrock. Muskeg peatlands developed over these poorly drained areas. The dom­inant plants of the muskeg ecosystem are Sphagnum mosses, whose decomposition leads to highly acidic waters with pH as low as 2.4. These waters drain off the muskegs into the cave sys­tems, eventually running to the ocean. In accordance with the Tongass Land Management Plan, one of the research priorities of the National Forest is to determine the contributions of karst groundwater systems to productivity of aquatic communities. On Northern Prince of Wales Island, the Conk Canyon Cave insurgence and the Mop Spring resurgence were continuously monitored to understand the buffering capacity of the cave sys­tem. Over the length of the system, the pH increases from an average 3.89 to 7.22. The insurgence water temperature, during the summer months, ranged from between 10oC to 17oC. Af­ter residence in the cave system, the resurgence water had been buffered to 6oC to 9oC. Over the continuum from insurgence to resurgence, the specific conductance had increased by an order of magnitude with the resurgence waters having a higher ionic strength. The cave environment acts as a buffer on the incom­ing acidic muskeg water to yield resurgence water chemistry of a buffered karst system. These buffered waters contribute to the productivity in aquatic environments downstream. The waters from this system drain into Whale Pass, an important location for the salmon industry. The cool, even temperatures, as well as buffered flow rates delivered by the karst systems are associated with higher productivity of juvenile coho salmon.


Karst, Uranium, Gold and Water Lessons from South Africa for Reconciling Mining Activities and Sustainable Water Use in Semi-arid Karst Areas: A Case Study, 2011,
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Winde, Frank

Despite the fact that much of the water stored in dams and reservoirs is lost to the atmosphere due to prevailing semi-arid conditions, South Africa traditionally relies mainly on surface water. Owing to an ever increasing demand that approaches the limits of economically exploitable surface water, the focus increasingly shifts towards groundwater as a long neglected resource. In this context, dolomitic karst aquifers that store large volumes of water protected from evaporation in vast underground cavities are of particular importance. This even more so as some of these aquifers are located in highly industrialised and densely populated areas such as the Gauteng Province, where water demand by far exceeds local supply and necessitates the expensive import of water from catchments as far as Lesotho. However, owing to impacts related to the century-old, deep-level gold mining that initiated South Africa’s economic development, many of the karst aquifers are currently not usable. Using the Far West Rand goldfield as an example, the extent, type and magnitude of mining-related impacts on dolomitic karst aquifers are analysed. This includes impacts on the geohydrological conditions in the area as well as water availability and ground stability associated with the large-scale dewatering of dolomitic aquifers that overly mine workings. Of particular concern is the mining-related contamination of groundwater and surface water with uranium which accompanies gold in most of the mined ore bodies. Finally, possible scenarios for water-related impacts of future mine closure are outlined and associated research needs identified. 


Landscape evolution in southeast Wales: evidence from aquifer geometry and surface topography associated with the Ogof Draenen cave system, 2011,
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Simms Michael J, Farrant Andrew R

The evolution of the Ogof Draenen cave system, in south-east Wales, has been profoundly influenced by the geometry of the karst aquifer and its relationship with changes in the surface topography. Using data from within the cave combined with a model of the aquifer geometry based on outcrop data, we have estimated the location and elevation of putative sinks and risings for the system by extrapolating from surveyed conduits in the cave. These data have enabled us to assess the scale and pattern of scarp retreat and valley incision in the valleys of the Usk, Clydach and Lwyd, that together have influenced the development of the cave. From this we can construct a relative chronology for cave development and landscape evolution in the region. Our data show that scarp retreat rates along the west flank of the Usk valley have varied by more than an order of magnitude, which we interpret as the result of locally enhanced erosion in glacial cirques repeatedly occupied and enlarged during successive glacial cycles. This process would have played a key role in breaching the aquiclude, created by the eastward overstep of the Marros Group clastics onto the Cwmyniscoy Mudstone, and thereby allowed the development of major conduits draining further south. In the tributary valleys incision rates were substantially greater in the Clydach valley than in the Lwyd valley, which we attribute to glacial erosion predominating in the north-east-facing Clydach valley and fluvial erosion being dominant in the south-facing Lwyd valley. There is evidence from within Ogof Draenen for a series of southward-draining conduits graded to a succession of palaeoresurgences, each with a vertical separation of 4-5 m, in the upper reaches of the Lwyd valley. We interpret these conduits as an underground proxy for a fluvial terrace staircase and suggest a direct link with glacial-interglacial cycles of surface aggradation and incision in the Lwyd valley. Fluvial incision rates for broadly analogous.


Influence of initial heterogeneities and recharge limitations on the evolution of aperture distributions in carbonate aquifers, 2011,
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Hubinger B. , Birk S.

Karst aquifers evolve where the dissolution of soluble rocks causes the enlargement of discrete pathways along fractures or bedding planes, thus creating highly conductive solution conduits. To identify general interrelations between hydrogeological conditions and the properties of the evolving conduit systems the aperture-size frequency distributions resulting from generic models of conduit evolution are analysed. For this purpose, a process-based numerical model coupling flow and rock dissolution is employed. Initial protoconduits are represented by tubes with log-normally distributed aperture sizes with a mean of 0.5 mm. Apertures are spatially uncorrelated and widen up to the metre range due to dissolution by chemically aggressive waters. Several examples of conduit development are examined focussing on influences of the initial heterogeneity and the available amount of recharge. If the available recharge is sufficiently high the evolving conduits compete for flow and those with large apertures and high hydraulic gradients attract more and more water. As a consequence, the positive feedback between increasing flow and dissolution causes the breakthrough of a conduit pathway connecting the recharge and discharge sides of the modelling domain. Under these competitive flow conditions dynamically stable bimodal aperture distributions are found to evolve, i.e. a certain percentage of tubes continues to be enlarged while the remaining tubes stay small-sized. The percentage of strongly widened tubes is found to be independent of the breakthrough time and decreases with increasing heterogeneity of the initial apertures and decreasing amount of available water. If the competition for flow is suppressed because the availability of water is strongly limited breakthrough of a conduit pathway is inhibited and the conduit pathways widen very slowly. The resulting aperture distributions are found to be unimodal covering some orders of magnitudes in size. Under these suppressed flow conditions the entire range of apertures continues to be enlarged. Hence, the number of tubes reaching aperture sizes in the order of centimetres or decimetres continues to increase with time and in the long term may exceed the number of large-sized tubes evolving under competitive flow conditions. This suggests that conduit development under suppressed flow conditions may significantly enhance the permeability of the formation e.g. in deep-seated carbonate settings.


The significance of turbulent flow representation in single-continuum models, 2011,
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Reimann T. , Rehrl C. , Shoemaker W. B. , Geyer T. , Birk S.

Karst aquifers evolve where the dissolution of soluble rocks causes the enlargement of discrete pathways along fractures or bedding planes, thus creating highly conductive solution conduits. To identify general interrelations between hydrogeological conditions and the properties of the evolving conduit systems the aperture-size frequency distributions resulting from generic models of conduit evolution are analysed. For this purpose, a process-based numerical model coupling flow and rock dissolution is employed. Initial protoconduits are represented by tubes with log-normally distributed aperture sizes with a mean ?0 = 0.5 mm for the logarithm of the diameters. Apertures are spatially uncorrelated and widen up to the metre range due to dissolution by chemically aggressive waters. Several examples of conduit development are examined focussing on influences of the initial heterogeneity and the available amount of recharge. If the available recharge is sufficiently high the evolving conduits compete for flow and those with large apertures and high hydraulic gradients attract more and more water. As a consequence, the positive feedback between increasing flow and dissolution causes the breakthrough of a conduit pathway connecting the recharge and discharge sides of the modelling domain. Under these competitive flow conditions dynamically stable bimodal aperture distributions are found to evolve, i.e. a certain percentage of tubes continues to be enlarged while the remaining tubes stay small-sized. The percentage of strongly widened tubes is found to be independent of the breakthrough time and decreases with increasing heterogeneity of the initial apertures and decreasing amount of available water. If the competition for flow is suppressed because the availability of water is strongly limited breakthrough of a conduit pathway is inhibited and the conduit pathways widen very slowly. The resulting aperture distributions are found to be unimodal covering some orders of magnitudes in size. Under these suppressed flow conditions the entire range of apertures continues to be enlarged. Hence, the number of tubes reaching aperture sizes in the order of centimetres or decimetres continues to increase with time and in the long term may exceed the number of large-sized tubes evolving under competitive flow conditions. This suggests that conduit development under suppressed flow conditions may significantly enhance the permeability of the formation, e.g. in deep-seated carbonate settings.


Mapping permeability over the surface of the Earth, 2011,
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Gleeson T. , Smith L. , Moosdorf N. , Hartmann J. , Durr H. H. , Manning A. H. , Van Beek L. P. H. , Jellinek A. M.

Permeability, the ease of fluid flow through porous rocks and soils, is a fundamental but often poorly quantified component in the analysis of regional-scale water fluxes. Permeability is difficult to quantify because it varies over more than 13 orders of magnitude and is heterogeneous and dependent on flow direction. Indeed, at the regional scale, maps of permeability only exist for soil to depths of 1–2 m. Here we use an extensive compilation of results from hydrogeologic models to show that regional-scale (>5 km) permeability of consolidated and unconsolidated geologic units below soil horizons (hydrolithologies) can be characterized in a statistically meaningful way. The representative permeabilities of these hydrolithologies are used to map the distribution of near-surface (on the order of 100 m depth) permeability globally and over North America. The distribution of each hydrolithology is generally scale independent. The near-surface mean permeability is of the order of 5 x 10-14 m2. The results provide the first global picture of near-surface permeability and will be of particular value for evaluating global water resources and modeling the influence of climate-surface-subsurface interactions on global climate change.

 

Glacier Caves, 2012,
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Gulley Jason D. , Fountain Andrew G.

The processes of cave formation in glaciers are analogous to cave formation in limestone and form from the preferential enlargement of high permeability pathways that connect discrete recharge and discharge points. Cave enlargement in glaciers is driven by small amounts of heat produced by friction as water flows through these high permeability pathways. Because rates of ice melting are many orders of magnitude faster than rates of the dissolution of limestone, glacier caves can grow to humanly traversable diameters within time scales of days to weeks whereas limestone caves of equivalent dimensions require 105–106 years. Because glacier ice is deformable, ice caves are squeezed shut at rates that increase with ice thickness, with deep caves squeezing closed in a matter of days. Glacier cave formation is therefore a dynamic process reflecting competition between enlargement and creep closure. While some glacier caves are reused and continue to evolve from year to year, many glacier caves must form each melt season. The processes of cave formation in glaciers exert important control on subglacial water pressure and affect how fast glaciers flow from higher, colder elevations, to lower warmer elevations. Ice flow directly into the ocean and glacial melt generally are important contributions to sea-level rise. Glacier caves are common in all glaciers that experience significant surface melting.


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