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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 stress, applied is the downward stress imposed at an aquifer boundary. it differs from effective stress in that it defines only the external stress tending to compact a deposit rather than the grain-to-grain stress at any depth within a compacting deposit [21].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Your search for lumped parameter model (Keyword) returned 7 results for the whole karstbase:
A parsimonious model for simulating flow in a karst aquifer, 1997, Barrett Me, Charbeneau Rj,
This paper describes the hydrologic system associated with the Barton Springs portion of the Edwards aquifer and presents a lumped parameter model capable of reproducing general historical trends for measured water levels and spring discharge. Recharge to the aquifer was calculated based on flow loss studies of the creeks crossing the recharge zone and on estimates of the rate of diffuse infiltration of rainfall. Flow measurements on each creek above and below the recharge zone were used to develop a relationship between how above the recharge zone and the rate of recharge. The five-cell groundwater model, each cell corresponding to one of the watersheds of the five main creeks crossing the recharge zone, was developed to support the management objectives of the City of Austin. The model differs from previous models in that the aquifer properties within cells are allowed to vary vertically. Each cell was treated as a tank with an apparent area and the water level of a single well in each cell was used to characterize the conditions in that cell. The simple representation of the hydrologic system produced results comparable to traditional groundwater models with fewer data requirements and calibration parameters. (C) 1997 Elsevier Science B.V

Identifying the flow systems in a karstic-fissured-porous aquifer, the Schneealpe, Austria, by modelling of environmental O-18 and H-3 isotopes, 2002, Maloszewski P. , Stichler W. , Zuber A. , Rank D. ,
The Schneealpe karst massif of Triassic limestones and dolomites with the altitude up to 1800 m a.s.l., situated 100 km SW of Vienna in Kalkalpen, is the main drinking water resource for the city. The catchment area of about 23 km(2) is drained by two springs: the Wasseralmquelle (196 Vs) and the Siebenquellen (310 1/s). This karstic aquifer is approximated by two interconnected parallel flow systems of: (a) a fissured-porous aquifer, and (b) karstic channels. The fissured-porous aquifer is of a high storage capacity and contains mobile water in the fissures and stagnant water in the porous matrix. The water enters this system at the surface and flows through it to drainage channels, which are regarded as a separate flow system, finally drained by both springs. The channels are also connected with sinkholes, which introduce additional water directly from the surface, Measurements of O-18 and tritium in precipitation and springs were modelled by a combined application of lumped-parameter models. Modelling yielded information on the mean values of the following hydraulic parameters: (1) The volume of water in the whole catchment area is 255 X 10(6) m(3), of which about 1.8 X 10(6) m(3) are in channels and 253 X 10(6) m(3) in the fissured-porous aquifer. (2) The total volumetric flow rate is 506 1/s, of which 77 1/s comprises direct flow from sinkholes to springs and 429 1/s are contributed to fissured-porous aquifer. (3) As the volume of the massif is 16.6 x 10 m(3), the total water saturated porosity (fissures and micropores of the matrix) is 1.5% and the channel porosity is about 0.01%. (C) 2002 Elsevier Science B.V. All rights reserved

Can we simulate regional groundwater flow in a karst system using equivalent porous media models? Case study, Barton Springs Edwards aquifer, USA, 2003, Scanlon B. R. , Mace R. E. , Barrett M. E. , Smith B. ,
Various approaches can be used to simulate groundwater flow in karst systems, including equivalent porous media distributed parameter, lumped parameter, and dual porosity approaches, as well as discrete fracture or conduit approaches. The purpose of this study was to evaluate two different equivalent porous media approaches: lumped and distributed parameter, for simulating regional groundwater flow in a karst aquifer and to evaluate the adequacy of these approaches. The models were applied to the Barton Springs Edwards aquifer, Texas. Unique aspects of this study include availability of detailed information on recharge from stream-loss studies and on synoptic water levels, long-term continuous water level monitoring in wells throughout the aquifer, and spring discharge data to compare with simulation results. The MODFLOW code was used for the distributed parameter model. Estimation of hydraulic conductivity distribution was optimized by using a combination of trial and error and automated inverse methods. The lumped parameter model consists of five cells representing each of the watersheds contributing recharge to the aquifer. Transient simulations were conducted using both distributed and lumped parameter models for a 10-yr period (1989-1998). Both distributed and lumped parameter models fairly accurately simulated the temporal variability in spring discharge; therefore, if the objective of the model is to simulate spring discharge, either distributed or lumped parameter approaches can be used. The distributed parameter model generally reproduced the potentiometric surface at different times. The impact of the amount of pumping on a regional scale on spring discharge can be evaluated using a lumped parameter model; however, more detailed evaluation of the effect of pumping on groundwater levels and spring discharge requires a distributed parameter modeling approach. Sensitivity analyses indicated that spring discharge was much more sensitive to variations in recharge than pumpage, indicating that aquifer management should consider enhanced recharge, in addition to conservation measures, to maintain spring flow. This study shows the ability of equivalent porous media models to simulate regional groundwater flow in a highly karstified aquifer, which is important for water resources and groundwater management. (C) 2003 Elsevier Science B.V. All rights reserved

Investigation of the groundwater residence time distribution in the Aladag (Kayseri-Adana, Turkey) karstic aquifer. PhD Thesis, 2004, Ozyurt, N. Nur

The Aladað karstic aquifer of Eastern Taurids Range extends between 400m and 3750m elevations and, covers an area of 1900 km2 within Adana-Kayseri-Niðde provinces. The study covers the Kapuzbaþý, Göksu shallow circulation and Yerköprü 1, Yerköprü 2 and Yerköprü 3 deep circulation springs that extend from recharge area to the Zamanti river.
The system is fed by precipitation of Mediterranean origin and total precipitation input, evapo-transpiration, net recharge and its volumetric equivalent are found to be 1113 mm, 451 mm, 879 mm and 939 106 m3. Mean annual discharges of Yerköprü 3, Yerköprü 1 and 2, Göksu and, Kapuzbaþý and Barazama springs are 449 106 m3, 82 106 m3, 299 106 m3 and 146 106 m3. Noble gas ( 20Ne, 40Ar, 84Kr) and 18O isotopes suggest recharge area elevation and temperature ranges of 1700-2100m and 2-6 oC. The helium (He) content of groundwater increases with increasing circulation depth. Year round biweekly-monthly samples’ electrical conductivity, tritium ( 3H) and 18O content reveal that Kapuzbaþý and Göksu springs and, Yerköprü 1 and Yerköprü 2 springs behave similarly among themselves.
The “CFC model ages” of the springs where, chlorofluorocarbon (CFC) contents increased from 1997 to 2002, range between 10 to 20 years and 20 to 30 years in the shallow and deep circulation parts, respectively. The 3H/3He* absolute age of groundwater from springs is around 20 +/- 2.5 years. In the computer code LUMPEDUS that was developed for unsteady state lumped parameter modeling applications, 3H, tritiogenic helium-3 ( 3He*), CFC-11, CFC-12, CFC-113, and 18O were used as environmental tracers. Serially connected plug-exponential flow model applied to all springs. All models were calibrated for observed outflux and their forecasted 3H, 3He* and 18O time series were found to be in good agreement with the observations. Mean residence times found by models are in agreement with 3H/3He* ages. According to residence time distribution suggested by models, most of the discharges comprise recharges that occurred within last 20 to 30 years. Sixty per cent of discharge comprises recharges of the last 3 to 4 years. The active reservoir volumes of Yerköprü 1-2, Kapuzbaþý, Göksu and Yerköprü 3 springs are found to be 1604 106 m3, 2808 106 m3, 5728 106 m3 and 8609 106 m3 , respectively. According to well established linear relationship between reservoir volumes and discharge elevations, an active volume increases 50 106 m3 per 1m decrease in elevation. Cumulative active reservoir volume is found to be 18749 106 m3 at 450 m elevation where Yerköprü 3 spring is located. Uppermost elevation of active reservoir is located at 836m. Groundwater’s velocity ranges from 2.09 m/day to 5.57 m/day and the corresponding hydraulic conductivities for different reservoirs are between 41.8 m/day and 212.2 m/day. The ordering of hydraulic conductivity among springs ( > > > ) seems to be related to their time of formation. Based on an assumption of 1500m of maximum hydraulic head at the recharge area, the effective porosity of the system is estimated to be 0.86 per cent.


Steady- and unsteady-state lumped parameter modelling of tritium and chlorofluorocarbons transport: hypothetical analyses and application to an alpine karst aquifer, 2005, Ozyurt N. N. , Bayari C. S. ,
Determination of a groundwater's mean residence time with the aid of environmental tracers is common in hydrogeology. Many of the lumped parameter (LP) applications used for this purpose have been based on steady-state models. However, the results may be misleading if a steady LP model is used to simulate the environmental tracer transport in an unsteady aquifer. To test this hypothesis, the results of steady and unsteady versions of several LP models were evaluated theoretically and in an alpine karst aquifer case by using tritium, oxygen-18 and chlorofluorocarbons (CFCs). The results reveal that the mean residence times obtained may be significantly different between the steady and unsteady versions of the same model. For the karst aquifer investigated, a serially connected exponential and a plug flow model were run under unsteady conditions. It is shown that outflux calibration with an unsteady model provides a firm basis in evaluating the results of models. An outflux-calibrated unsteady model predicted reasonably the observed series of water isotopes. The calibrated model's CFCs output overpredicts the observed concentrations, probably because of the time lag in the unsaturated zone of the alpine karst aquifer. Copyright (c) 2005 John Wiley & Sons, Ltd

Mixing of shallow and deep groundwater as indicated by the chemistry and age of karstic springs, 2006, Toth D. J. , Katz B. G.

Large karstic springs in east-central Florida, USA were studied using multi-tracer and geochemical modeling techniques to better understand groundwater flow paths and mixing of shallow and deep groundwater. Spring water types included Ca–HCO3 (six), Na–Cl (four), and mixed (one). The evolution of water chemistry for Ca– HCO3 spring waters was modeled by reactions of rainwater with soil organic matter, calcite, and dolomite under oxic conditions. The Na–Cl and mixed-type springs were modeled by reactions of either rainwater or Upper Floridan aquiferwater with soil organic matter, calcite, and dolomite under oxic conditions and mixed with varying proportions of saline Lower Floridan aquifer water, which represented 4–53% of the total spring discharge. Multiple-tracer data—chlorofluorocarbon CFC-113, tritium (3H), helium- 3 (3Hetrit), sulfur hexafluoride (SF6)—for four Ca–HCO3 spring waters were consistent with binary mixing curves representing water recharged during 1980 or 1990 mixing with an older (recharged before 1940) tracer-free component. Young-water mixing fractions ranged from 0.3 to 0.7. Tracer concentration data for two Na–Cl spring waters appear to be consistent with binary mixtures of 1990 water with older water recharged in 1965 or 1975. Nitrate-N concentrations are inversely related to apparent ages of spring waters, which indicated that elevated nitrate-N concentrations were likely contributed from recent recharge.


Residence time distribution in the Kirkgoz karst springs (Antalya-Turkey) as a tool for contamination vulnerability assessment, 2007, Ozyurt N. Nur
Lumped parameter modeling of environmental tracer (tritium, CFCs and tritiogenic helium-3) transport in the Kirkgoz karst springs (Antalya-Turkey) appears to be a useful tool for assessing the vulnerability to contamination. Based on tritium observations between 1963 and 2000, the springs revealed a mean residence time (MRT) of 120 years. This suggests an active transport volume of 71 billion cubic meters for the aquifer, a value that is coherent with the estimated void volume of karst aquifer based on the mass of associated travertine deposits. The CFC-11 and CFC-12 MRTs are in agreement with tritium-based MRT, after correcting for excess air effect. Excess crustal and mantle helium flux hindered the use of tritiogenic helium-3 as a potential tracer. The residence time distribution (RTD) indicates a groundwater transport system that is fed by recharges extending back to past several hundred years. This wide RTD suggests that any recent contamination that may have entered the system could progress slowly within the entire aquifer but would be unnoticed in the early period because of the dilution effect of uncontaminated past recharge waters. Once the contamination is recognized, it may last for many centuries ahead even if the contamination practice is stopped. Thus, control of contaminant release to aquifer and monitoring of contaminant level in Kirkgoz springs is an immediate task for the associated public health authorities.

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