Karst and Cave RSS news feed Like us on Facebook! follow us on Twitter!
Community news

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 prusik knot is a knot tied by looping a smaller diameter rope around a larger standing line (rope) that has the property of sliding with no load on the knot, but will hold when it is loaded (e.g. when the weight of a caver is applied) [13]. see also ascender; mechanical ascender; prusiking; standing line.?

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

What is Karstbase?

Search KARSTBASE:

keyword
author

Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for availability (Keyword) returned 54 results for the whole karstbase:
Showing 1 to 15 of 54
Variation among populations of the yroglobitic Amphipod Crustacean Crangonyx Antennatus Packard (Crangonyctidae) living in different habitats Il. Population distribution., 1982, Dickson Gary W.
Population densities and factors affecting the distribution of the troglobitic (i.e., obligatory cavernicole) amphipod Crangonyx antennatus were examined in two distinct aquatic habitats. Observations were made seasonally for one year in six Lee Co., Virginia (U.S.A.) caves, three with mud-bottom pools and three with gravel-bottom streams. Pool habitats were found to contain greater C. antennatus densities than stream habitats, while the highest seasonal densities were recorded in August. Availability of food is considered to be the major factor allowing these increased population densities. The population distribution of C. antennatus was not found to be related to current velocity, water depth, macro-detrital food sources or isopods densities in both pool and stream habitats. The distribution of C. antennatus was observed to be related to substrate type. Substrate selection appeared to be passive in five of the amphipod populations, while in one cave, substrate selection may be influenced by competitive interactions. The fact that population distributions were not related to environmental parameters which differ markedly between habitats indicates that this troglobitic species retains ecological flexibility.

Prediction of Climatic Temperature Data for Karst Areas in the Central and Southern Tablelands of New South Wales, 1983, Halbert, Erik J. M.

The use of multiple regression analysis is shown to overcome current limitations in availability of climatic temperature data for caving sites in the Central and Southern Tablelands of New South Wales. The developed equations are used to calculate climatic data for Jenolan, Wellington, and Oberon which agree well with recorded data at these sites. The equations are also used to calculate data for six major caving areas in New South Wales, including the tourist areas Wombeyan and Yarrangobilly and frequently visited areas such as Bungonia and Wee Jasper.


A new topofil, 1992, Warild, Alan

A light, compact, reliable instrument for surveying difficult vertical caves has been a drean of cave surveyors for many years. The topofil described goes a long way towards fulfilling that ideal, although there are still problems of availability and user error. Even so, the author is of the firm opinion that topofils are ideal for expedition and deep cave surveys.


Abstract: Eastern Australian Quaternary mammal faunas: their palaeoclimatic and faunistic setting - and their potential IN: Proceedings of the Wombeyan Karst Workshop November 19-22, 1993 , 1993, Ride, W. D. L.

The availability of extensive palaeoclimatic information and the realisation that the cave deposits of eastern Australia extend back into the Tertiary, and the recognition that virtually the whole of the characteristic marsupial fauna are arid adapted, it seems likely that the caves have the potential to illustrate the whole of the spectacular and rapid Australian radiation after the loss of the rainforests.


SPELEOGENESIS IN AEOLIAN CALCARENITE - A CASE-STUDY IN WESTERN VICTORIA, 1994, White S. ,
Most studies of karst landscapes and their processes have been concerned with consolidated, often well-jointed limestones. There are particular problems involved in the study of karst procesess in softer, less-compact limestones such as chalk, coral reefs, and aeolian calcarenite. Previous studies in aeolian calcarenite indicated these problems and a scheme was developed of speleogenesis in aeolian calcarenite. A study of karst processes in aeolian calcarenite at Bats Ridge in western Victoria has developed this scheme further. The karst features and processes at Bats Ridge are an integral part of the landscape of a mid-Pleistocene calcarenite dune system. The resolution of problems of the rapid subaerial speleogenesis in the area is achieved by the synthesis of the known karst features of the ridge and the geology and geomorphology of the area. Karst development on this aeolianite ridge depends on lithological conditions as well as the availability of aggressive water capable of solution. The diagenesis of the calcarenite is occurring now and must have been occurring by the mid-Pleistocene. This simultaneous lithification of the carbonate dunes into aeolian calcarenite rock and the development of solutional karst features in the dunes is the characteristic feature of the speleogenesis in this area. It is the formation of a hardened kankar layer (cap rock) in the dunes of sufficient compressive and tensile strength to support cavities, which is the result of these interrelated factors, that has strongly determined the formation of the karst features

Stable Isotope Analysis of Human Remains: A Tool for Cave Archaeology, 1997, Trimble, C. C. , Macko, S. A.
Stable isotope analysis of human remains is a research tool that can provide paleodiet information for archaeological sites, such as caves, where traditional evidence may be missing or out of context. Unlike other lines of evidence, the stable isotopes of carbon and nitrogen in human bone reflect the chemistry of the diet and therefore provide a direct measure of the foods consumed. As an example, the data from isotopic analyses of bone from the Mer site (44LE280), a cave in Lee County, Virginia, are presented. Although this site lacks faunal and floral remains to provide basic information about the availability and potential utilization of food resources, the stable isotope data from other sites throughout Virginia and North Carolina provide a basis for comparison. The d13C and d15N values for the cave burials suggest a diet composed of primarily C4 plant proteins and some terrestrial animal proteins.

Proteus for sale and for science in the 19th Century, 1999, Shaw, Trevor R.

The cave-dwelling amphibian Proteus, first described in 1768, and possibly pictured as early as the 11th century, was by 1800 known to many scholars. From 1814 when the animals were more widely found, they were sold in markets, at inns in Postojna and sometimes outside the cave there; and guidebooks drew attention to their availability. The paper documents all this and examines what happened to the animals. Some were given to zoos; others were kept by amateur naturalists; some went to laboratories; and a few were eaten. One was offered to Darwin.


Spatial and temporal patterns of bacterial density and metabolic activity in a karst aquifer, 2001, Simon K. S. , Gibert J. , Petitot P. , Laurent R. ,
Karst aquifers are heterotrophic ecosystems fueled by organic matter imported from the surface. The temporal pattern of floods influences organic matter import and the spatial distribution of organic matter and biofilms in aquifer structural zones. We investigated spatial and temporal patterns of bacterial density and activity as indicators of energy availability and microbial dynamics in a karst aquifer. During baseflow, bacterial density and microbial hydrolytic activity were similar in the upper and lower zones of the aquifer. Floods apparently scoured aquifer biofilms and trans ported soil bacteria into the aquifer, increasing inactive bacterial density in the water column. Respiring bacterial density did not respond to floods and changed little over time. The overall proportion of total bacteria that were respiring was very high on some dates, resulting from a reduction of inactive cell density during flood recession. Floods appear to be key events in scouring senescent microbial assemblages in karst aquifers and stimulating microbial recolonization of the aquifer matrix. We conclude that a conceptual model of karst aquifer structure and function should incorporate changes caused by alternation between flooding and drying in the aquifer

Mn-Fe deposits in shallow cryptic marine environment: examples in northwestern Mediterranean submarine caves, 2001, Allouc J, Harmelin Jg,
Black coating of hard substrates by Mn and Fe oxides has long been reported from shallow, dark, submarine caves. However, these littoral metallic deposits have never been studied in detail, despite expected analogies with deep-sea polymetallic crusts. Submarine caves are characterized by darkness and low rates of exchanges with the open sea. Lack of primary production and confinement of inner water bodies result in marked oligotrophy and extremely reduced biomass, i.e. conditions close to those prevailing in deep-sea habitats. Field evidences suggested that the formation of Mn-Fe coatings was closely tied to these particular environmental conditions. The goal of this study was to examine the detailed features of Mn-Fe coatings from dark caves with different local conditions, and to try to identify the processes responsible for their deposition. Study sites and methods Three sublittoral, single-entrance, caves were sampled by scuba diving along the coasts of Provence (France, Mediterranean Sea) (fig. 1). The first site is a large karstic cave (Tremies Cave, 16 m depth at entrance floor, 60 m long; Marseille-Cassis area) with an ascending profile which results in a buffered thermal regime and markedly oligotrophic conditions due to warm water trapping in its upper part (fig. 1 and 2). Wall fragments were sampled at 30 m (medium confinement : zone B) and 60 in (strong confinement : zone C) from the cave entrance. The second site is a large tubular cavity open in conglomerate formations (3PP Cave, 15 m depth at entrance floor, 120 m long; La Ciotat) with a descending profile which results in relative permanence of winter temperatures within the inner parts, complex water circulation and presumed greater input of sedimented particles than in the preceding cave (fig.1 and 2). Wall samples were taken at 25 m, 70 in and 100 m from entrance. The third site is a small, horizontal, cave open in quartzite formations (Bagaud Cave, 7 in depth at entrance floor, about 10 m long; WNW of Port-Cros Island, bay of Hyeres). Sampling was performed on walls of a narrow corridor between an anterior room and a smaller inner room. A sporadic outflow of continental waters is located in the inner room. The samples were preserved in 50% ethylic alcohol or studied soon after their sampling. Before carbon coating and SEM examination, or microanalyses with SEM-associated spectrometers, they were treated in a 33% Chlorox solution and thereafter washed in demineralized water and dried. Micromorphology At low-medium magnification (<20,000), the aspect of coatings varies between caves and, especially, between inner-cave locations. All the described structures are made up of Mn and Fe oxides. In Tremies Cave, coatings of walls from zone B are composed of irregular erected constructions (height : 10s to 100s μm) formed by the aggregation of roughly ovoid primary concretions of about 10 μm (fig. 3). The surface of those primary concretions displays numerous lacunose to reticulate films (pores, about 0.5 μm in diameter, are often subrounded). Remnants of these films and organomorphic corpuscles occur also within the primary concretions (fig. 4). On younger substrates (broken wall exposed since 1970), primary concretions are poorly developed and no prominent construction is visible (fig. 5). In more confined conditions (zone C), the erected constructions of ancient coatings are smaller and less numerous than in zone B but are well individualized (fig. 6). In this zone: C, besides some remnants of lacunose to reticulate films (fig. 7), there is an appearance of filaments and ovoid corpuscles (height/width : 10-30/5-15 μm), which seem to be linked to filaments by a short stalk (fig. 8). In 3 PP Cave, at 25-70 m from entrance, wall coatings present porous heaps of primary concretions (fig. 9). The surface and the inside of the latter comprise remnants of lacunose to reticulate films that evoke those observed in Tremies Cave (fig. 10 and 11). On younger substrates (hard parts of sessile invertebrates), coatings are restricted to micrometric organomorphic corpuscles with some remnants of lacunose or fibrous films (fig. 12). At 100 in from the entrance, coatings are shaped by numerous erected constructions, more or less coalescing (fig. 13). Besides remnants of lacunose films, the primary concretions contain interlacing filaments (diameter : 0.2-0.3 μm) forming cords or veils (fig. 14). In Bagaud Cave, the primary concretions are aggregated in irregular heaps (fig. 15). Lacunose films are particularly frequent and tend to form three-dimensional mamillated structures that were not observed in the other caves (fig. 16). In particular, there is an appearance of tubular structures (fig. 17) and of numerous hemispheroidal structures (diameter : 4-5 μm) with an upper orifice (fig. 18 and 19). At higher magnification (20,000), whatever the cave and inner-cave location, the aspect of oxide deposits is rather smooth or, especially, microgranular (fig. 20). Mineral composition The composition of coatings is different between caves and according to their inner-cave location. In both large caves (Tremies and 3 PP), the Mn/Fe ratio increases with the distance from the cave entrance, i.e. when exchanges with the open sea diminish (fig. 21a). This trend is particularly clear in Tremies Cave, where the confinement gradient is strongly marked. Besides, the Mn/Fe ratio also seems to increase when films are present in the analysed volume (some cubic micrometers) (fig. 21b). In Bagaud Cave, the Mn/Fe ratio reaches high values despite the small size of this cave and its low confinement level. Discussion and conclusions SEM observations suggest that in each studied cave, the Mn-Fe coatings are biosedimentary deposits. Genesis of these deposits is assumed to result mainly from the replacement of biofilms (composed of cells and slime, i.e, of extracellular polymeric substance produced by microorganisms) generated by microbial populations colonizing the cave walls. Considering the darkness of the cave-locations, microbes consist mainly in bacteria, but fungi are probably responsible for the filaments and ovoids corpuscules (evoking sporocysts) occurring in innermost parts. Observations at different scales of the morphological features of oxide deposits reveal a structured organisation which varies along the strong environmental gradients (particularly the confinement level) that occur from the entrance to the innermost parts : erected constructions made up of primary concretions become more and more defined and acquire a pseudo-columnar shape. The aspect of biofilms appears to be controlled by the same environmental parameters. In open or relatively open environments, they frequently show a three-dimensional development (with frequent skullcape-like shapes), while in more confined conditions they exhibit a planar layout. These changes reflect either the adaptation of the slime-producing bacteria to the local trophic resources (correlated to the rate of exchange with the open sea) and water movements, or spatial replacement of taxa. It is assumed that slime (mainly composed of water and exopolysaccharides) induces a local increase of the concentration in dissolved Mn and acts as an ion exchange resin that allows the retention of Mn on the functional groups of EPS. These conditions promote the nucleation of Mn oxide crystallites in the slime. Then. the anionic character of Mn oxides in seawater, and their capacity to catalyse the oxydation of Mn2 to Mn4, allow the process to go on without any other biological intervention; thus, the process of crystal growth becomes possible. In caves where Mn is only supplied by seawater (Tremies and 3 PP), the average value of the Mn/Fe ratio of coatings is negatively correlated to the local availability of nutrients. This trend is probably linked to changes in the selectivity of slimes towards the processes of retention of cations, because this ratio is clearly influenced by the occurrence of biofilms. However, independently from trophic resources, the Mn/Fe ratio can be notably increased when additional Mn is provided by the seeping or flowing of continental waters (Bagaud Cave)

Revising the Karst Map of the United States, 2002, Veni, G.
The production of the recently published Living with karst: Afragile foundation required a map showing the distribution of karst in the United States. William Davies et al. (1984) produced the last such map. I used their work as the basis in developing a revised US karst map, but delineated karst primarily on lithology rather than cave lengths. The categories are: exposed and buried carbonate and evaporite karst, and volcanic and unconsolidated pseudokarst. The new US karst map updates the previous map with data from more detailed regional karst maps. Scale and information availability limited the accuracy of the new map. Buried evaporites and unconsolidated pseudokarst are underrepresented due to insufficient delineation. I had to interpolate from available information to adjust for discrepancies due to different map projections and differences between maps. The new US karst map improves on earlier versions but is still incomplete and of low precision in some areas. Production of detailed karst maps with drainage basins and other land management factors is best left to state agencies. The US Geological Survey is developing a new US karst map and the NSS Section of Cave Geology and Geography is assisting with that effort. Uniform standards need to be established for definitions, scale, and map projections. Section members include the countrys most knowledgeable karst geoscientists and they play key roles in developing an accurate and definitive US karst map.

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

Symposium Abstract: Does quarrying affect water availability in the adjacent unsaturated zone?, 2003, Smart P. L. , Groves C, Cant E, Jones A. , Maurice L.

Cadmium and zinc adsorption maxima of geochemically anomalous soils (Oxisols) in Jamaica, 2003, Davies Be, Vaughan J, Lalor Gc, Vutchkov M,
Soil samples were collected from a Miocene limestone area of Jamaica (Manchester Parish) where unusual accumulations of Cd and other metals have been described previously. The source of the metals is natural (geological). The soils are aluminous Oxisols and, geochemically, are closely similar to local karst bauxite deposits. For comparison a karst bauxite sample was collected from Alabama (USA) and an Ultisol sample from South Carolina (USA). All the Jamaican soils were in the pH range neutral to slightly alkaline and CaCO3 contents ranged from 1.3 to 23.1 %. Mean total Cd = 102.5 mg/kg (range 13.6-191.8 mg/kg) and mean Zn = 362.6 (range = 125.8-683.3) mg/kg. These values are higher than world averages. The mean readily exchangeable Cd was 0.05 (range 0.01-0.15) mmol/kg and for Zn mean = 0.02 (range 0.01-0.02) mmol/kg. Adsorption data were obtained experimentally and modelled using the Langmuir isotherm. For the Manchester soils the mean Cd adsorption maximum was 9.15 (range 2.26-32.0) mmol/kg; the values were higher than the karst bauxite sample (0.08 mmol/kg) or the Ultisol (0.08 mmol/kg). Reliable Zn isotherms were not obtained for all soils; for three Manchester soils the mean Zn sorption maximum was 2.99 mmol/kg compared with 3.13 mmol/kg for Cd in the same three soils. Mean Al and Fe values are 38.7% Al2O3 and 17.7% Fe2O3 compared with the Ultisol (14.5% Al2O3,11.3% Fe2O3) and the bauxite (52.6% Al2O3, 0.7%Fe2O3). Interpretation of the major element values and the known mineralogy of the soils implies that the high adsorption maxima of the Manchester soils can best be explained by their calcareous nature. It is concluded that the Manchester soils have ample adsorption capacity to trap any incoming Cd or Zn solutes

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

Hydrogeologic and climatic influences on spatial and interannual variation of recharge to a tropical karst island aquifer, 2003, Jones I. C. , Banner J. L. ,
[1] The hydrology and geochemistry of groundwater in tropical island aquifers, such as on Barbados, are significantly influenced by tropical climatic conditions. Recharge to these aquifers is the product of regional and local climate patterns that control rainfall. Oxygen isotopes can be used to estimate the amount and timing of recharge on these islands because seasonal fluctuations of rainwater oxygen isotopic compositions are related to the amount of rainfall. This study shows that estimates of average annual recharge to the limestone aquifer on Barbados vary widely, displaying a more direct relationship to the distribution of rainfall throughout each year than to total annual rainfall. Recharge estimates are higher during years when rainfall is concentrated in the peak wet season months than during years when rainfall is more evenly distributed throughout the year. The El Nino-Southern Oscillation appears to be partially responsible for these rainfall and recharge fluctuations. Knowledge of interannual variation of recharge and processes responsible is important because recharge variation must be considered when setting groundwater management policies related to groundwater availability

Results 1 to 15 of 54
You probably didn't submit anything to search for