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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 debris is 1. any material found to have been washed into a cave from some other locality. 2. coarse rock fragments resulting from erosion and disintegration of bedrock [16].?

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Karst environment, Culver D.C.
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Your search for unsaturated zone (Keyword) returned 66 results for the whole karstbase:
Showing 1 to 15 of 66
Anomalous behaviour of specific electrical conductivity at a karst spring induced by variable catchment boundaries: the case of the Podstenjšek spring, Slovenia, , Ravbar, N. , Engelhardt, I. , Goldscheider, N.

Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in Slovenia during 26 high-flow events in an 18-month monitoring period. A conceptual model explaining this anomalous SEC variability is presented and reproduced by numerical modelling, and the practical relevance for source protection zoning is discussed. After storm rainfall, discharge increases rapidly, which is typical for karst springs. SEC displays a first maximum during the rising limb of the spring hydrograph, followed by a minimum indicating the arrival of freshly infiltrated water, often confirmed by increased levels of total organic carbon (TOC). The anomalous behaviour starts after this SEC minimum, when SEC rises again and remains elevated during the entire high-flow period, typically 20–40 µS/cm above the baseflow value. This is explained by variable catchment boundaries: When the water level in the aquifer rises, the catchment expands, incorporating zones of groundwater with higher SEC, caused by higher unsaturated zone thickness and subtle lithologic changes. This conceptual model has been checked by numerical investigations. A generalized finite-difference model including high-conductivity cells representing the conduit network (“discrete-continuum approach”) was set up to simulate the observed behaviour of the karst system. The model reproduces the shifting groundwater divide and the nearly simultaneous increase of discharge and SEC during high-flow periods. The observed behaviour is relevant for groundwater source protection zoning, which requires reliable delineation of catchment areas. Anomalous behaviour of SEC can point to variable catchment boundaries that can be checked by tracer tests during different hydrologic conditions.


Carbon dioxide in the atmosphere of the unsaturated zone: an important control of groundwater hardness in limestones, 1977, Atkinson T. C.

Water movement and storage in the unsaturated zone of a maturely karstified carbonate aquifer, Mendip Hills, England,, 1987, Smart P. L. , Friederich H.

Le karst de Vaucluse (Haute Provence), 1991, Mudry J. , Puig J. M.
The catchment area of the Fontaine de Vaucluse system is more than 1100km2 wide, with an average altitude of 870m. The thickness of the Lower Cretaceous limestone (1500m) gives the system a very thick (800m) unsaturated zone. Karstification is highly developed (four shafts are more than 500m deep) as well as on the valley (pit of 300m depth inside the spring). The bottom of the shafts of the Plateau does not reach the saturated zone of the karst, as their flows are the chemical content of the seepage water. The maximum hydraulic gradient from the Plateau to the spring is low, only 0.3%. Dye tracings permit the assignment of the Ventoux-Lure rang (including its calcareous northern slope with a southward dipping) and the Vaucluse Plateau in the catchment area. The water balance computed by altitude belts shows that the rainfall strongly increases with altitude: 120mm at 200m, 1380mm over 1800m. The dynamic of the system, studied by discharge and physical and chemical content, shows of a well karstified media, that reacts with slight inertia upon the rainy periods, and that is made up of important reserves, particularly within the unsaturated zone, that supply long decline and depletion episodes.

ORIGIN AND MORPHOLOGY OF LIMESTONE CAVES, 1991, Palmer A. N. ,
Limestone caves form along ground-water paths of greatest discharge and solutional aggressiveness. Flow routes that acquire increasing discharge accelerate in growth, while others languish with negligible growth. As discharge increases, a maximum rate of wall retreat is approached, typically about 0.01-0.1 cm/yr, determined by chemical kinetics but nearly unaffected by further increase in discharge. The time required to reach the maximum rate is nearly independent of kinetics and varies directly with flow distance and temperature and inversely with initial fracture width, discharge, gradient, and P(CO2). Most caves require 10(4) - 10(5) yr to reach traversable size. Their patterns depend on the mode of ground-water recharge. Sinkhole recharge forms branching caves with tributaries that join downstream as higher-order passages. Maze caves form where (1) steep gradients and great undersaturation allow many alternate paths to enlarge at similar rates or (2) discharge or renewal of undersaturation is uniform along many alternate routes. Flood water can form angular networks in fractured rock, anastomotic mazes along low-angle partings, or spongework where intergranular pores are dominant. Diffuse recharge also forms networks and spongework, often aided by mixing of chemically different waters. Ramiform caves, with sequential outward branches, are formed mainly by rising thermal or H2S-rich water. Dissolution rates in cooling water increase with discharge, CO2 content, temperature, and thermal gradient, but only at thermal gradients of more than 0.01-degrees-C/m can normal ground-water CO2 form caves without the aid of hypogenic acids or mixing. Artesian flow has no inherent tendency to form maze caves. Geologic structure and stratigraphy influence cave orientation and extent, but alone they do not determine branch-work versus maze character

Symposium Abstract: Tracing of waterflow in the unsaturated zone above White Scar Cave [Yorkshire], 1992, Bottrell S. H. , Atkinson T. C.

WATER-BUDGET, FUNCTIONING AND PROTECTION OF THE FONTAINE-DE-VAUCLUSE KARST SYSTEM (SOUTHEASTERN FRANCE), 1992, Blavoux B, Mudry J, Puig Jm,
The karst aquifer of the well-known Fontaine de Vaucluse has been recently studied, results have been got about delimitation of the system and its working. Geological data (lithology and structure) have allowed to delimit an 1115 Km2 intake area including Ventoux-Lure north facing range (1,909-1,826 m) and the Plateau which is prolonging it southwards (Fig. 1 and 2). The average altitude of the whole area, obtained by balancing elevation belt surfaces, is about 870 m. This elevation squares with results of tracing tests (Fig. 3), environmental physical, chemical and isotopic tracings, that allow to value a 850 m average altitude for the intake area (Fig. 4). The moisture balance has been computed from an altitude belts climatic model, using local rain an temperature gradients (Fig. 5 and Table II), because the weather network is not representative. So, rainfalls rise of about 55 mm per 100 m elevation and temperature decreases of about 0.5-degrees-C per 100 m. The consequence of these two antagonist phenomena is the quasi constant value of actual evapotranspiration on each altitude belt. With the Fig. 7 organigram, curves of effective rainfalls and infiltration coefficient versus elevation can be plotted (Fig. 6). This computation shows that 3/4 of the total and the whole of dry season effective rainfalls are provided by the part of the intake area situated above the average altitude: on the lowest belt, effective rainfalls are only 120 mm per year and increase to 1380 mm on the upper section (Fig. 8 and Table 1). The weighted effective rainfalls are about 570 mm per year for the whole intake area. Hydrodynamical and physico-chemical studies show, despite its large size, the weak inertia of the system, so proves its good karstification, that confirms for the whole system the pin-point speleological observations. The discharge of the spring, which average value is 21 m3.s-1 (only 18 for the last ten years), can exceed 100 m3.s-1 and the minimum has never been lower than 3.7 m3.s-1 (Fig. 9). When it rains on the intake area, the increase of the discharge is very sudden in a rainy period : one to four days. This short delay is due to seepage through epikarst and unsaturated zone. During dry periods, the spring reaction is deadened, due to storage in the unsaturated zone. The silica content distribution was plotted during several hydrokinematical phases (Fig. 10). It shows: an almost unimodal distribution for the 8 km2 fissured limestone aquifer of Groseau; a multimodal one for the 1115 km2 karst aquifer of Fontaine de Vaucluse. This proves that karstification is more important than size in the response of the system. Weak summer rainfalls do not influence the discharge, nevertheless they influence chemistry of the spring water, and so interrupts the water depletion phasis. Then, the decrease of discharge can continue after the end of the chemical depletion phasis, water which is overflowing after summer rainfalls (in a dry period) is influenced hy the chemistry of seepage water : on the graph of a principal components analysis, done on chemical variables. an hysteresis phenomenon can be seen (Fig. 11). A discriminant analysis (Fig. 12) confirms that these autumn waters, with high ratio seepage tracers, are not reserve waters from the saturated zone. The ratio of reserve water in the total discharge, is preponderant: 3/4 and 2/3 respectively of the yearly runoff volumes for 1981 and 1982 (Fig. 13), but an important part of these reserves can be stored in the unsaturated zone. This storage capacity can be valued by different means: transposing to Vaucluse (1115 km2) the volume measured on another karst system in the Pyrenees (13 km2); it gives about 100 million m2; using setting parameters of Bezes model (1976) on the same aquifer: it gives 113 million m3; using depletion curves, that show, for instance during the 1989 summer and autumn dry period, a 80 million m3 volume. In all cases, we get a value of about one hundred million m3 for the storage capacity of the unsaturated zone. With a 20 m range of fluctuation for the water table and with a 10(-2) specific yield, on a 500 to 1,000 km2 saturated zone, the zone of fluctuation can release about 10 to 20 million m3. Then, the volume of water stored in the whole saturated zone, with a 300 m minimum thickness (depth of the waterlogged pit of the Fontaine), a 500 km2 minimum surface and a 10(-3) specific yield, is about 150 million m3, including 27 million m3 stored in the channels. So, the unsaturated zone represents a significant part of the whole storage capacity and most of the yearly renewable reserves. Paradoxically, the biggest french spring is not tapped at all; as its intake area is neither a regional nor a national park, no general protection covers it : because of its good karstification, the vulnerability of the system is important. Good quality of water is attributable to the low population and human activities density on the intake area (4 inh.km-2). A great part of the intake area is uncultivated (large forest and ''garrigues'' areas). Due to the lack of surface water and scantness of soils, agriculture is not intensive (lavender, thyme, sage and bulk wheat fields. meadowlands). On the mountainous zone, roads are salted in winter and snowmelt water can reach a significantly high chloride ratio than in a natural climatic functioning (for instance 25 mg.l-1 in Font d'Angiou where the ratio would have been 3 mg.l-1). As tourism is developing both on the mountain and on the plateau, the management of the highest intake area must be carefully held: its part is preponderant in the feeding of the system

Isotopic investigation of infiltration and unsaturated zone processes at Carlsbad Cavern, 1992, Chapman J. A. , Ingraham N. L. , Hess J. W.

Tracer study and storage in the unsaturated zone of a karstic limestone aquifer, 1992, Bottrell S. H. , Atkinson T. C.

Paleoclimate implications of mass spectrometric dating of a British flowstone, 1995, Baker A, Smart Pl, Edwards Rl,
The timing of growth phases in a cave flowstone from Yorkshire, England, has been precisely dated by thermal ionization mass spectrometric 238 U- 234 U- 230 Th dating. Six growth periods of both short duration and fast growth rate are separated by nondepositional hiatuses. The ages of these phases were determined to be 128.8 or -2.7, 103.1 or -1.8, 84.7 or -1.2, 57.9 or -1.5, 49.6 or -1.3, and 36.9 or -0.8 ka. There is a remarkably good correlation between the periods of active speleothem growth and the timing of solar insolation maxima, derived from orbital parameters, which has not previously been reported. Speleothem growth theory and evidence from other terrestrial paleoclimate records suggest that episodic, rapid growth phases at the insolation maxima are most likely to be caused by changes in either precipitation intensity or volume, which caused switching in the routing of water flow in the unsaturated zone above the cave. Such a result provides new evidence of the importance of variations in solar insolation for terrestrial paleoclimate and offers the potential for derivation of a paleowetness index from speleothem growth

INFILTRATION MECHANISMS RELATED TO AGRICULTURAL WASTE TRANSPORT THROUGH THE SOIL MANTLE TO KARST AQUIFERS OF SOUTHERN INDIANA, USA, 1995, Iqbal M. Z. , Krothe N. C. ,
A hydrogeological study was conducted, during the 1991-1992 water year, in the clay-soil mantled portion of a limestone terrain in southern Indiana. The purpose of the study was to investigate the modes of soil-water infiltration contributing to rapid transport of nitrate to the saturated zone. The I-year-cycle profiles of nitrate concentration vs. time show a consistent increase of nitrate at various depths in the unsaturated zone during the period of investigation. The increase of nitrate in soil water is attributed to the rapid flushing of the inorganic fertilizers from the fields after the area received sufficient rainfall in late fall. The investigation also showed a major movement of nitrate in quick pulses through the unsaturated zone, rather than a slow uniform recharge, immediately after a major storm event. The asymmetric profiles of nitrate concentration vs. depth point to the existence of preferential flow through macropores in the clay-soil mantle above the bedrock. Soil-water transport between storm events is by matrix type flow. Nitrogen isotopes were analyzed for representative groundwater samples collected before and immediately after fertilization of fields in the summer, 1991. The delta(15)N values of the samples did not show any major shift in nitrate sources between the sampling periods. The summer of 1991 was extremely dry prohibiting vertical transport of nitrate from the fields to the groundwater system. Any change in nitrate concentration in groundwater during this time is attributed to the mixing through lateral flow within the aquifer

Migration of dissolved petroleum hydrocarbons, MTBE and chlorinated solvents in a karstified limestone aquifer, Stamford, UK, 1998, Banks D,
Two incidents of hydrocarbon contamination to the Lincolnshire Limestone in east Stamford, UK, have been investigated. No evidence of LNAPL contamination of groundwater was observed, suggesting that the spills may largely have been retained in the unsaturated zone. Some groundwater contamination by dissolved hydrocarbons occurred, apparently especially at times of high recharge. Rapid flow paths were proven to nearby springs in the River Welland (with groundwater flow velocities of up to 240 m day-1), and dissolved hydrocarbon and MTBE contamination appears to have been flushed rapidly from these systems. MTBE contamination at Tallington Pumping Station (5 km east of the site) is not clearly linked to these incidents. Of potentially more concern was the discovery of dissolved chlorinated solvent contamination in the groundwater at the spill sites, possibly related to a landfilled quarry and/or a nearby engineering works. No direct evidence of DNAPL was observed. A conceptual model of solvent distribution suggests independent sources of TCE, PCE and TCA

Mapping groundwater vulnerability: the Irish perspective, 1998, Daly D, Warren Wp,
The groundwater protection scheme used in the Republic of Ireland since the 1980s had not encompassed the vulnerability mapping concept. Yet internationally, vulnerability maps were becoming an essential part of groundwater protection schemes and a valuable tool in environmental management. Consequently, following a review of protection schemes world-wide, the scheme used in Ireland was updated and amended to include vulnerability maps as a crucial component of the scheme. The approach taken to vulnerability assessments and mapping in the Republic of Ireland has been dictated by the following fundamental questions: Vulnerability of what? Vulnerability to what? Which factors determine the degree of vulnerability? What is the appropriate scale for map production? How can limitations and uncertainties be taken into account? How can vulnerability assessments be integrated into environmental and resource management? The following decisions were made: (i) we should map the vulnerability of groundwater, not aquifers or wells/springs; (ii) the position in the groundwater system specified to be of interest is the water-table (i.e. first groundwater encountered) in either sand/gravel aquifers or in bedrock; (iii) we should map the vulnerability of groundwater to contaminants generated by human activities (natural impacts are a separate issue); (iv) as the main threat to groundwater in Ireland is posed by point sources, we should map the vulnerability of groundwater to contaminants released at 1-2 m below the ground surface; (v) the characteristics of individual contaminants should not be taken into account; (vi) the natural geological and hydrogeological factors that determine vulnerability are the sub-soils above the watertable, the recharge type (whether point or diffuse) and, in sand/gravels, the thickness of the unsaturated zone; (vii) based on these factors, four vulnerability categories are used (extreme, high, moderate and low); (viii) map scales of 1:50 000 and 1:10 000 are preferred; (ix) limitations and uncertainties are indicated by appropriate wording on the maps and a disclaimer; (x) vulnerability maps should be incorporated into groundwater protection schemes, which should be used in decision-making on the location and control of potentially polluting developments. Vulnerability maps have now been produced for a number of local authority areas. They are an important part of county groundwater protection schemes as they provide a measure of the likelihood of contamination, assist in ensuring that protection schemes are not unnecessarily restrictive of human economic activity, help in the choice of engineering preventative measures, and enable major developments, which have a significant potential to contaminate, to be located in areas of relatively low vulnerability and therefore of relatively low risk, from a groundwater perspective

Recharge: the key to groundwater pollution and aquifer vulnerability, 1998, Robins N. S. ,
Recharge is pivotal to understanding the processes by which groundwater pollution can occur. It is implicit in the classification of aquifer units according to their vulnerability to pollution. The management of both groundwater resources and of individual groundwater sources cannot sensibly be undertaken without some knowledge of recharge: its quantity, its seasonality and, above all, the different routes through the sub-soil and the unsaturated zone by which it can occur. However, current estimates of recharge, other than on a research site basis, may be poor, both in the UK and overseas. This volume provides a review of current research into these issues; this introductory paper attempts to highlight the thread throughout all of this work which collectively provides the basic information in support of the current and future management of groundwater resources and sources

The hydrogeological effect of quarrying karstified limestone: options for prediction and mitigation, 1998, Hobbs S. L. , Gunn J. ,
The hydrogeological effect of limestone extraction from open pits (quarries) depends on the location of the site in the landscape, the vertical and horizontal extent of the excavation, the methods used to excavate the stone, and the extent of karstification. Groundwater quality is commonly affected by quarrying through increased fine sediment concentrations and accidental spillages. Removal of any soil cover allows direct access for pollutants into the aquifer, a problem which may be exacerbated by licensed or illegal tipping of waste following cessation of stone extraction. Quarrying also removes the entire subcutaneous (epikarstic) zone which is an important ground-water store, together with part or all of the unsaturated zone. Pumping of water from the excavation will change the ground-water balance and can alter the direction and amounts of conduit flow, particularly if the quarry extends beneath the water table. Prediction of such impacts is difficult, especially when the limestone is karstified, such that there will always be a degree of uncertainty associated with the impact of the workings. Hence, it is essential that for new quarries monitoring is undertaken prior to, throughout, and following mineral working, with options for mitigation if mineral working causes an unacceptable impact. When a quarry ceases to be worked, the direct impacts on groundwater quality may rapidly decrease but there are important implications for after-use of the site. Impacts on groundwater quantity are likely to be more long-term

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