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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 hydraulic discharge is the discharge of ground water through springs or wells [16].?

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Karst environment, Culver D.C.
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Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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Your search for diffuse flow (Keyword) returned 31 results for the whole karstbase:
Showing 1 to 15 of 31
Karst Geomorphology of the Bruce Peninsula, Ontario, PhD Thesis, 1976, Cowell, Daryl William

This is the first detailed examination of the karst geomorphology of the Bruce Peninsula. It attempts to review all aspects including pavement phenomena and formation (microkarst features), surface and subsurface karst hydrology (meso to macro scale) and water chemistry. The latter is based on over 250 samples collected in 1973 and 1974.
The dolomite pavement is the best example of its kind that has been described in the literature. It covers much of the northern and eastern parts of the peninsula and can be differentiated into three types based on karren assemblages. Two of these are a product of lithology and the third reflects local environmental controls. The Amabel Formation produces characteristic karren such as rundkarren, hohlkarren, meanderkarren, clint and grike, kamentizas and rillenkarren on glacially abraded biohermal structures. The Guelph Formation develops into a very irregular, often cavernous surface with clint and grike and pitkarren as the only common recognizable karren. The third assemblage is characterized by pitkarren and is found only in the Lake Huron littoral zone. Biological factors are believed to have played a major role in the formation of the pavement. Vegetation supplies humic acids which help boost the solution process and helps to maintain a wet surface. This tends to prolong solution and permit the development of karren with rounded lips and bottoms.
Three types of drainage other than normal surface runoff are found on the Bruce. These are partial underground capture of surface streams, complete underground capture (fluvio-karst), and wholly vertical drainage without stream action (holokarst). Holokarst covers most of the northern and eastern edge of the peninsula along the top of the escarpment. Inland it is replaced by fluvial drainage, some of which has been, or is in the process of being captured. Four perennial streams and one lake disappear into sinkholes. These range from very simple channel capture and resurgence, as shown by a creek east of Wiarton, to more mature and complex cave development of the St. Edmunds cave near Tobermory. Partial underground capture represents the first stage of karst drainage. This was found to occur in one major river well inland of the fluvio-karst and probably occurs in other streams as well. This chapter also examines the possible future karst development of the Bruce and other karst feature such as isolated sinks and sea caves.
The water chemistry presented in Chapter 5 represents the most complete data set from southern Ontario. It is examined on a seasonal basis as well as grouped into classes representing water types (streams, Lake Huron and Georgian Bay, inland lakes, swamps, diffuse springs and conduit springs). The spring analyses are also fitted into climatic models of limestone solution based on data from other regions of North America. It was found that solution rates in southern Ontario are very substantial. Total hardness ranges from 150 to 250 ppm (expressed as CaCO3) in most lakes and streams and up to 326 ppm in springs. These rates compare with more southerly latitudes. The theoretical equilibrium partial pressure of CO2 was found to be the most significant chemical variable for comparing solution on different kinds of carbonates and between glaciated and non-glaciated regions. Expect for diffuse flow springs and Lake Huron, the Bruce data do not separate easily into water types using either graphical or statistical (i.e. Linear Discriminant Analysis) analyses. This is partly because of the seasonality of the data and because of the intimate contact all waters have with bedrock.


Diffuse flow and conduit flow in limestone terrain in the Mendip Hills, Somerset (Great Britain), 1977, Atkinson T. C.
The hydrogeology of the karstic Carboniferous Limestone is described. Water tracing has established recharge areas for fifteen major springs and water budgets confirm the size of the areas found. Groundwater flow occurs in two modes: turbulent conduit flow and diffuse Darcian flow in fine fractures. Recharge is 50% quickflow via caves and closed depressions and 50% slower percolation. Active storage in the diffuse component (S = 0.92%) is 30 times greater than in phreatic conduits. Diffuse hydraulic conductivity is 0.89 m day−1 and an average of 60?80% of groundwater is transmitted by conduits in this maturely karsted and steeply dipping aquifer.

Diffuse flow and conduit flow in limestone terrain in the Mendip Hills, Somerset (Great Britain), 1977, Atkinson T. C.

Hydrology and hydrochemistry of the Caves Branch karst, Belize, 1983, Miller T. ,
A large conduit spring issuing from Cretaceous limestones in Belize, Central America, displays a positive relation of discharge to solute concentration. Beneath a maturely-dissected cockpit karst, the hydrologic system combines allogenic surface water from an invasion polje with authigenic karst water. Dynamic mixing produces three climatically-induced discharge phases: baseflow, normal, and high-stage flow. Each has an associated hydrochemical regime, predominantly diffuse-flow karst water. An areal solute concentration of ~80 mg l-1 Ca2 is estimated, with a “denudation rate” of 100 mm per 1000 yr

TEMPORAL CYCLES OF KARST DENUDATION IN NORTHWEST GEORGIA, USA, 1994, Kiefer R. H. ,
Time patterns of karst denudation in northwest Georgia (U.S.A.) were investigated at three spring sites for 12 months and at five stream sites for 10 years. Rainfall was evenly distributed and showed no significant seasonality. At the springs, as well as the streams, water hardness was largely controlled by discharge. At the springs, Soil PCO2 and water pH were strongly correlated (r = -0.69 to -0.83). Solute transport in spring waters was highly seasonal, with two conduit flow springs removing more limestone in the winter, and the diffuse flow spring removing more during the growing season. At the stream sites, most denudation occurred during the winter and spring seasons, and least during the summer. Fourier analysis showed that variations in denudation occur on deterministic (long-wave) as well as stochastic (short-wave) time scales. As contributing variables, discharge varied in short-wave and long-wave cycles, whereas soil PCO2 showed only a long-wave cycle. The 12 month deterministic cycles were the most important, with changes in discharge taking precedence over Soil PCO2. Time series regression explains up to 69 per cent of changes in denudation through rain and soil pCO2. Time cycles in available water are the key controlling factor of denudation, and amounts of available Soil CO2 may not be as important in the temporal patterns of karst downwearing as has been believed previously

ASSESSING FLOW SYSTEMS IN CARBONATE AQUIFERS USING SCALE EFFECTS IN HYDRAULIC CONDUCTIVITY, 1994, Rovey C. W. ,
Counter to intuition, small-scale measurements of hydraulic conductivity do not average to regional values. Instead, mean hydraulic conductivity increases with measurement scale up to a critical distance termed the range, beyond which a constant regional value prevails. Likewise, variance in log hydraulic conductivity increases with separation distance between measurement points as the spatial correlation decreases. As dissolution proceeds in carbonate aquifers, heterogeneity and the volume necessary for an equivalent homogeneous medium (EHM) both increase. As these variables increase, the range of scale increase in both mean hydraulic conductivity and variance increases proportionately. Consequently, the range in scale effects is a reliable measure of the degree of secondary dissolution. By correlating the numeric value of range with independently measured hydraulic properties, the prevalent type of flow system, diffuse, mixed or conduit can be determined

Hydrochemographs of Berghan Karst Spring as Indicators of Aquifer Characteristics, 1997, Raeisi, E. , Karami, G.
Berghan Spring is located in the southern part of Iran, northwest of Shiraz. The catchment area of the spring consists of the southern flank of the Gar Anticline, which is made up of the karstic calcareous Sarvak Formation. There are no sinkholes or other karst landforms in the catchment area. Because of the existence of several faults, the aquifer has been brecciated and may have caused karstification to occur in most of the pores and fissures. The specific conductance, pH and water temperature were measured once every twenty days for a period of 32 months and water samples were analyzed for major anions and cations. Flow rate was measured daily during the recession, and once every three weeks during the rest of the study period. Using the WATEQF computer model, the partial pressure of carbon dioxide and the saturation index of calcite and dolomite also were estimated. Three distinct periods, the first recession, the second recession, and precipitation, were observed in the hydrograph of Berghan Spring. No considerable differences were observed between the first and second recession coefficients. Base flow constitutes 71.5%, 100% and 66.2% of total flow in the first recession period, the second recession period and the precipitation period, respectively. The variation of specific conductance, calcium and bicarbonate concentrations and calcite saturation indices are not significant during the study period, implying that aquifer characteristics control the chemical behavior of the spring. The morphology and geology of the Berghan Spring catchment area, and data from hydrographs and chemographs, show that the hydrologic system is dominantly diffuse flow. Evidence for this is shown by autogenic recharge, a brecciated aquifer, and small values and slight differences in hydrograph recession coefficients. In addition, specific conductance, calcium and bicarbonate concentrations, and water temperature did not show significant variations during the study period suggesting a diffuse flow aquifer.

Simulated effect of vadose infiltration on water levels in the Northern Guam Lens Aquifer, 2000, Contractor Dn, Jenson Jw,
Regional-scale hydrology of the fresh water lens in the Northern Guam Lens Aquifer has been simulated in the past using a finite element, sharp interface computer model, SWIG2D. Systematic differences exist between observed and computed water levels. Computed seasonal peak water levels are higher, and the computed seasonal lows are lower than the respective observed levels. It is hypothesized that vadose storage must store a substantial amount of water during the wet season and release it gradually into the lens during the dry season. Flow through the vadose zone was simulated with a one-dimensional finite element, unsaturated flow program UNSATID, in which the van Genuchten model is used to characterize unsaturated diffuse flow through the matrix of the vadose zone. An additional parameter (SINK) was added to the van Genuchten set to account for rapid infiltration down open pathways (fractures) associated with the closed depressions of the karst terrain. A global-optimization technique (Shuffled Complex Evolution or SCE-UA Method) was used to obtain the parameters that minimized the difference between simulated and observed water levels. Simulations incorporating the van Genuchten model were accomplished by combining the two programs, UNSATID and SWIG2D, into a single program. The sum-of-squared-errors (SSE) between computed and observed water levels in four observation wells was minimized using SCE-UA, reducing the arithmetically averaged SSE of the four wells by 30% compared with the SSE obtained when the vadose zone was not modeled. These results suggest that vadose storage is significant. On the other hand, the fact that the best fit obtained with an optimum parameter set was able to reduce the SSE by no more than 30% suggests that additional phenomena have yet to be accounted for to mon fully explain differences between simulated and observed well water levels. (C) 2000 Elsevier Science B.V. All rights reserved

A four-component mixing model for water in a karst terrain in south-central Indiana, USA. Using solute concentration and stable isotopes as tracers, 2001, Lee E. S. , Krothe N. C. ,
The study area lies in a highly karstified carbonate terrain in south central Indiana. Sinkholes, conduits, and caves form large secondary pathways for the subsurface flow. As a result, the discharge from a main emergence point for the subsurface flow system, the Orangeville Rise, quickly responds to the storm events and shows wide variations in flow rate, water chemistry, and stable isotopic compositions. These responses are attributed to the mixing of water in secondary pathways. In the study area, recharge occurs through the thick, mantled karst plain and the sinkhole plains, and the role of soil layer and epikarst in the recharge process is of great importance. Rain (DIC: 2 HCO3- mg/l, delta C-13 (DIC): - 7%o) soil water (DIC: 544 HCO3- mg/l, delta C-13(DIC): - 14.7%o), epikarstic water (DIC: 224 HCO3- mg/l delta C-13(DIC): - 13.6%o), and phreatic diffuse flow water (DIC: 299 HCO3- mg/l, delta C-13(DIC): - 11.8%o) generally showed unique and constant dissolved inorganic carbon (DIC) and delta C-13(DIC) values over time. Using DIC and delta C-13(DIC) as tracers, a four-component mixing model was established for the karstic flow system. By constructing the discharge hydrograph separation curves, the mixing ratio of each component, rain (10.6%), soil (3.1%), epikarstic (52.3%), and phreatic (34.0%) water, was determined for the Orangeville Rise discharge over the testing period of 104 h after the storm event of 10/4/90. Vadose water occupied 55.4% of spring discharge and this demonstrates the importance of the unsaturated zone, especially the epikarst, in the karstic flow systems. (C) 2001 Elsevier Science B.V. All rights reserved

Derivation of effective hydraulic parameters of a karst aquifer from discharge hydrograph analysis, 2001, Baedke Sj, Krothe Nc,
In well-developed karst terrains, three or more distinct portions of the karst continuum can be identified from hydrographs of springs issuing from the karat aquifer. Hydrographs from mio karat springs within the same drainage basin at the Crane Naval Surface Warfare Center, Indiana, have been analyzed, and ratios of transmissivity and specific yield (T/S-y) have been established for the conduit and diffuse flow systems. These ratios have been compared with values of T derived from aquifer tests, so that independent values of S-y can be calculated for the diffuse system. Similarly, if the value of S-y is assumed to be 1.0 for a pure conduit, then independent values of T can be calculated for this end-member of the karst continuum. The values of T and S-y derived from this study are similar to values obtained from a dye trace of the conduit-dominated flow system and of values derived from aquifer tests of the diffuse flow system. Values of T for the conduit system of these springs may need to be established at a local scale, while the values for the diffuse flow system may be applicable at a regional scale. A hydrograph separation using isotopic data suggests that the intermediate-flow system represents a mix of water from the conduit and diffuse flow systems. If this portion of the hydrograph is a truly mixing phenomena, ratios of TIS cannot be determined from the hydrograph analysis presented herein. However. if instead, the intermediate-flow system represents water released from a third reservoir (such as small fractures), ratios of T/S, can be established for the intermediate-flow system

Delineating the karstic flow system in the upper Lost River drainage basin, south central Indiana: using sulphate and delta S-34(SO4) as tracers, 2003, Lee E. S. , Krothe N. C. ,
A karstic flow system in the upper Lost River drainage basin in south central Indiana, USA, was investigated using SO4 concentration and delta(34)S(SO4) as tracers. The flow system was characterized as vadose flow and phreatic diffuse flow. Vadose-flow samples were collected from 7 epikarstic outlets after storm events. Phreatic diffuse flow samples were collected from the Orangeville Rise, the major emergence point for the drainage basin, during the base flow periods. Discharge from the Orangeville Rise was constant during the base flow periods but showed large variations in flow rate (0.3-11.7 m(3)/S), SO4 concentration (11-220 mg/l), and delta(34)S(SO4), ( 5.2 to 15.0parts per thousand) after storm events, due to the mixing of rain, vadose flow, and phreatic diffuse flow in the conduits that feed the Orangeville Rise. Sulphate concentrations and delta(34)S(SO4), were unique in vadose flow (S-SO4: 13-24 mg/l; delta(34)S(SO4),: 1.9 to 3.8parts per thousand) and phreatic diffuse flow (SO4: 220 mg/l; delta(34)S(SO4),: 15.0parts per thousand). Mean SO4 concentration of rainwater in the study area was measured as 1.8 mg/l. Using a 3-component mixing model for water in the karstic conduits, the mixing ratios of rain (16.5%), vadose flow (58.5%), and phreatic diffuse flow (25.0%) components were calculated in the Orangeville Rise discharge. These mixing ratios attained using SO4 concentration as a tracer indicated the important role of the vadose zone as a water storage area in karst aquifers. (C) 2002 Published by Elsevier Science Ltd

Linear model describing three components of flow in karst aquifers using O-18 data, 2004, Long A. J. , Putnam L. D. ,
The stable isotope of oxygen, 180, is used as a naturally occurring ground-water tracer. Time-series data for 5 180 are analyzed to model the distinct responses and relative proportions of the conduit, intermediate, and diffuse flow components in karst aquifers. This analysis also describes mathematically the dynamics of the transient fluid interchange between conduits and diffusive networks. Conduit and intermediate flow are described by linear-systems methods, whereas diffuse flow is described by mass-balance methods. An automated optimization process estimates parameters of lognormal, Pearson type III, and gamma distributions, which are used as transfer functions in linear-systems analysis. Diffuse flow and mixing parameters also are estimated by these optimization methods. Results indicate the relative proximity of a well to a main conduit flowpath and can help to predict the movement and residence times of potential contaminants. The three-component linear model is applied to five wells, which respond to changes in the isotopic composition of point recharge water from a sinking stream in the Madison aquifer in the Black Hills of South Dakota. Flow velocities as much as 540 m/d and system memories of as much as 71 years are estimated by this method. Also, the mean, median, and standard deviation of traveltimes; time to peak response; and the relative fraction of flow for each of the three components are determined for these wells. This analysis infers that flow may branch apart and rejoin as a result of an anastomotic (or channeled) karst network. Published by Elsevier B.V

Flow system dynamics and water storage of a fissured-porous karst aquifer characterized by artificial and environmental tracers, 2005, Einsiedl F,
Concentration breakthrough curves obtained from a tracer test and time series of environmental tracers were analyzed to characterize slow and preferential water flow in a karst aquifer of the Franconian Alb, Germany. Tritium (H-3) and chemical tracers (uranine, bromide, strontium) were measured during low flow conditions and a storm runoff event. The mean transit time of water along the conduits was determined using bromide. Environmental tracer data collected between 1969 and 2003 were modeled to estimate the mean transit time of H-3 in the fissured-porous karst system (diffuse flow). The modelling approach was also used to estimate the water volume of the karst system and the conduits. The results suggest that the total water volume in the fissured-porous karst aquifer is in the range of 57 X 10(6) m(3) and approximately 6% of the total water volume is stored in the soil zone and the epikarst. The water storage capacity of the conduits seems to be of minor importance. A mean transit time of bromide in the range of 14 h was calculated for the conduit flow. The fissures and the porous rock matrix have a calculated water saturated porosity of 5.5% and a mean transit time of approximately 62 years was calculated. Thus the porous rock matrix represents the major dilution and storage zone for pollutants in the karst system. (c) 2005 Elsevier B.V. All rights reserved

Spatial and temporal changes in the structure of groundwater nitrate concentration time series (1935-1999) as demonstrated by autoregressive modelling, 2005, Jones A. L. , Smart P. L. ,
Autoregressive modelling is used to investigate the internal structure of long-term (1935-1999) records of nitrate concentration for five karst springs in the Mendip Hills. There is a significant short term (1-2 months) positive autocorrelation at three of the five springs due to the availability of sufficient nitrate within the soil store to maintain concentrations in winter recharge for several months. The absence of short term (1-2 months) positive autocorrelation in the other two springs is due to the marked contrast in land use between the limestone and swallet parts of the catchment, rapid concentrated recharge from the latter causing short term switching in the dominant water source at the spring and thus fluctuating nitrate concentrations. Significant negative autocorrelation is evident at lags varying from 4 to 7 months through to 14-22 months for individual springs, with positive autocorrelation at 19-20 months at one site. This variable timing is explained by moderation of the exhaustion effect in the soil by groundwater storage, which gives longer residence times in large catchments and those with a dominance of diffuse flow. The lags derived from autoregressive modelling may therefore provide an indication of average groundwater residence times. Significant differences in the structure of the autocorrelation function for successive 10-year periods are evident at Cheddar Spring, and are explained by the effect the ploughing up of grasslands during the Second World War and increased fertiliser usage on available nitrogen in the soil store. This effect is moderated by the influence of summer temperatures on rates of mineralization, and of both summer and winter rainfall on the timing and magnitude of nitrate leaching. The pattern of nitrate leaching also appears to have been perturbed by the 1976 drought. (C) 2005 Elsevier B.V. All rights reserved

Application of spectral analysis of daily water level and spring discharge hydrographs data for comparing physical characteristics of karstic aquifers, 2005, Rahnemaei M. , Zare M. , Nematollahi A. R. , Sedghi H. ,
Bivariate time series techniques (in spectral domain) of daily rainfall and water level of piezometers or discharge of springs in karstic aquifers are employed to evaluate the lag times (delay) of aquifers response to rainfall events. The evaluation results show that the physical characteristics of karstic aquifers can be compared with each other by using the outcomes of these analyses. With attention to dual porosity idea of karstic aquifers, two lag times (t(1), t(2)) can be computed, which, are related to flow of water through larger fractures (conduit flow) and matrix of the rock (diffuse flow), respectively. Results obtained from these functions, correspond to the findings of physical characteristics, compiled from field investigations. Comparable to dual porosity idea in regard to recharge through the larger fractures (in the first step) and finer porosity of the rock (in the second step), the idea of 'Dual Recharge' in karstic aquifers is presented. Application of these techniques is verified using daily rainfall and water level of Qara, Sabzpooshan and Kaftarak piezometers and daily discharge of Qasreqhomsheh karst spring in Maharlu basin in Iran (52 degrees 20 '-52 degrees 40 ' E and 29 degrees 20 '-29 degrees 40 ' N) having different degree of karstification in their surroundings. (c) 2005 Elsevier B.V. All rights reserved

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