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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 formation is the fundamental unit in rock-stratigraphic classification, consisting of a distinctive mappable body of rock [10]. see also cave formation; speleothem.?

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Chemistry and Karst, White, William B.
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for recession (Keyword) returned 80 results for the whole karstbase:
Showing 1 to 15 of 80
Significance and origin of very large regulating power of some karst aquifers in the Middle East. Implication on karst aquifer classification, , Elhakim M, Bakalowicz M,
SummaryKarst aquifers are the main groundwater resource in Lebanon as well as in most Mediterranean countries. Most of them are not exploited in a sustainable way, partly because their characteristics remain unknown. Karst aquifers are so complex that the assessment of their resource and their exploitable storage requires an analysis of their whole functioning, particularly by analysing the spring hydrograph. Among all various methods, the method proposed by Mangin aims to characterize at the same time the recharge conditions and the storage and recession of the saturated zone by analyzing the spring hydrograph. This method defines two parameters, the infiltration delay i, and the regulating power k which are the roots of a classification of karst systems. This classification makes the distinction between karst and porous aquifers considering the value of the regulating power. k is assumed to be lower than 0.5 in karst, and between 0.5 and 1 for all other aquifers, 1 being the upper limit.The study of karst aquifers in Lebanon shows values of k > 0.5, and even 1; former data from the literature show that other karst springs in Middle East have comparable characteristics. In fact, what is not considered by Mangin and others, k is equivalent to a mean residence time in years of water in the saturated zone. So long residence times are normally observed in poorly karstified aquifers, or containing abandoned, not functioning karstification. The geological framework in which the studied springs are located in fact shows that these aquifers have been subject to a long, complex evolution, as a consequence of the base level rising. This rising produced the flooding of the successive karst drainage network, which does not really function anymore and provides a large storage capacity to the aquifer. The very interesting properties of these aquifers make them prime targets for fulfilling the increasing needs of water

Paleohydrology and Streamflow Simulation of three Karst Basins in Southeastern West Virginia, U.S.A., PhD Thesis, 1975, Coward, Julian Michael Henry

This study was undertaken to gain a better understanding of karst hydrology. To do this, the present day hydrology and the paleohydrology were determined in three karst basins. The basins chosen were the Swago, Locust and Spring Creek basins in Pocahontas and Greenbrier Counties, West Virginia. A number of conventional field techniques were used successfully in this study, including the following: current meter and dye dilution gauging; dye and lycopodium stream tracing; geological and cave mapping; the setting up of stage recorders; geochemistry; and limestone erosion measurements. The climate of the region was investigated to obtain realistic precipitation, temperature and potential evaporation data over the study basins.
It was found that the mean precipitation over two of the basins was 30% higher than recorded data in the valleys. The karst development of the basins was found to take place in four major stages. These were: A) initial surficial flow, B) strike controlled drainage, C) major piracies from one sub-basin to another, and D) shortening of the flow routes. The major controls on the karst development were found to be: A) the Taggard shale, B) the strike direction, which controlled early basin development, and C) the hydraulic gradient from the sink to rising, which controlled later basin development.
To better assess the quantitative hydrology, and to assist in determining the type of unexplorable flow paths, a watershed model was developed. This modelled the streamflow from known climatic inputs using a number of measured or optimized parameters. The simulation model handled snowmelt, interception, infiltration, interflow, baseflow, overland flow, channel routing, and evaporation from the interception, soil water, ground water, snowpack and channel water. The modelled basin could be split up into 20 segments, each with different hydrological characteristics, but a maximum of 3 segments was used in this study.
A total of 29 parameters was used in the model although only 10 (other than those directly measurable) were found to be sensitive in the three basins. The simulated streamflow did not match the real flows very well due to errors in the data input and due to simplifications in the model. It was found, however, that as the proportion of the limestone in a segment increased the overland flow decreased, the interflow increased, the baseflow and interflow recessions were faster, the soil storages were smaller and the infiltration rate was higher, than in segments with a larger proportion of exposed clastics. The flow characteristics of the inaccessible conduits were inferred from the channel routing parameters and it was postulated that the majority of the underground flow in the karst basins was taking place under vadose conditions.


Geomorphology of the North Karst, South Nahanni River Region, Northwest Territories, Canada, PhD Thesis, 1976, Brook, George Albert,

First investigated on the ground in June 1972, the Nahanni karst of northern Canada is the most complex karst terrain yet reported from high latitudes. It is centered at 61°28' N, longitude 124°05' W and lies within the zone of discontinuous permafrost. Mean annual temperature is 24°F and mean total precipitation 22.3 inches. Principal karst forms are fracture-located karst streets and irregularly-shaped closed depression called karst platea which may be up to 600 feet in depth. Platea often contain karst towers which are residuals of wall recession. Vertical-walled pond dolines up to 120 feet deep are common in bare karst areas while subjacent karst collapse, subsidence and suffosion depressions occur on marginal shale- and drift-mantled surfaces. Three small poljes have been identified, two produced entirely by solution, the other a structural form. These are periodically inundated. There are several peripheral fluvial canyons up to 3,000 feet deep that are blocked by glacial drift and which presently drain underground. Similarity in the hydrogeological properties of Nahanni Formation limestones at a variety of scales has led to the development of morphologically-identical karst forms which range in size from inches up to hundreds of feet. Furthermore, many of these landforms are part of a developmental sequence that at one scale links vertical-walled dolines, karst streets, platea and poljes; and at another links solution pits, grikes and joint hollows on limestone pavements. The evidence suggests that poljes form by the coalescence of dolines and uvalas just as Cvijic suggested in 1918. In attempting to explain the almost "tropical" nature of the sub-arctic Nahanni karst landform assemblage, a number of facts are of importance.
(a) The Nahanni Formation limestones have been highly warped and intensively fractures during the past one million years. Open fractures have encouraged karstification by allowing easy movement of water underground. Warping has provided the relief necessary for the development of solutional forms with a distinct vertical component.
(b) The karst can not be considered relict because it was glaciated during the Pleistocene. In addition the hydrological activity in it today is comparable with that in many humid tropical karst areas.
(c) Solutional denudation rates governed by aspects of surficial and bedrock geology may in some localized areas be equivalent to rates in humid tropical carbonate regions.
(d) At present rates, the most highly developed forms could have been produced within the last 200,000 years and because there is evidence to indicate that the karst may not have been glaciated for up to 250,000 years, such a period has been available for solutional development.
Because the Nahanni region has not been glaciated for an extremely long period, it may be one of only a few high-latitude carbonate terrains that have had time to develop fully. Its very existence questions the validity of the concept that the intensity and direction of karst development is climate-controlled. In the Nahanni at least, the structural and lithological properties of the host limestone appear to have been of greater importance. The labyrinth karst type present in regions of humid-tropical to sub-arctic climate, is an outstanding example of a structurally-controlled karst landscape. It may well be that the same controls also influence the distributions of other karst types.


Relation dbit / niveau de la mer de l'mergence littorale d'Almyros Agios Nikolaos (Crte, Grce), 1983, Bezes C. , Joseph C.
RELATION FLOW-SEA LEVEL OF SALT KARSTIC RESURGENCE BY MULTIPLE REGRESSION WITH THE WATER TABLE - The Amlyros Agios Nikolaos spring is a brackish karstic resurgence on the eastern coast of Crete. Its flow varies in the reverse order versus the sea level. The circulation of the out effect recession curve of the spring was done with the building of a multiple regression between the sea level, the spring flow and the water table. An adjustment about the mean sea level ensures the preservation of outflow.

Uranium-Series Ages of Speleothem from Northwest England: Correlation with Quaternary Climate, 1983, Gascoyne M, Schwarcz Hp, Ford Dc,
Over 180 $^{230}$Th/$^{234}$U ages have been obtained for 87 speleothems from caves in the Craven district of northwest England. Periods of abundant speleothem growth, 0-13, 90-135 and 170 to > 350 ka, are correlated with interglacial isotope stages 1, 5 and 7-9 respectively. Periods of zero growth, 14-35 and 140-165 ka, are correlated with glacial stages 2 and 6 respectively. A prominent break in growth of one speleothem, dated at about 260 ka, may be correlated with glacial stage 8. Lower-frequency growth from 35 to 90 ka is correlated with stages 3 and 4. The results may also be related to the British Quaternary sequence within the range of $^{14}$C determinations, as follows: 0-13 ka. Flandrian plus late Devensian deglaciation; 14-35 ka, late Devensian glaciation; 35-45 ka. Upton Warren interstadial. Low but finite speleothem abundance during the period 45-90 ka correlates with the early Devensian and is in good agreement with evidence indicating the non-glacial, but tundra-like, climate over this period. The Ipswichian interglacial is broadly related to the abundant growth period 90-135 ka, but is more closely defined by the interval 115-135 ka, from results of dating speleothems enclosing remains of Ipswichian fauna in one cave. By analogy with the zero speleothem abundance during the late Devensian glaciation, the period 140-165 ka may be tentatively correlated with the Wolstonian glaciation. Lack of direct stratigraphic relationships with, or absolute ages of, middle to early Pleistocene stages prevents further correlation of speleothem age data. From the frequency of abundance of speleothem basal ages for the period 0-13 ka, it appears that speleothem growth lags ice recession by up to 4 ka

The Hydrology of a Glacierised Alpine Karst Castlegaurd Mountain, Alberta, PhD Thesis, 1983, Smart, Charles Christopher

Alpine karst throughout the world has been affected by past glaciation, and yet little is known of the interactions between glacier ice and karst. This dissertation attempts to gain some understanding of the problem through the study of the Castleguard Area, Alberta, where a karst aquifer is presently overlain by temperate glacier ice.
Quantitative fluorometric tracing and hydrometric measurements generated a broad data base on aquifer behaviour. Tracer breakthrough curves were interpreted using a new systematic approach which considers an explicit set of processes likely to affect the particular tracer under the given experimental conditions. Non-linearity in aquifer behaviour and rapid groundwater velocities demonstrated the aquifer to be an extreme conduit type Conduit springs are elements in a vertical hierarchy in which the topmost springs are "overflows" and exhibit greater flow variability than their associated "underflows". A numerical model was developed to simulate a conduit aquifer. It demonstrated that pulse train and recession analysis widely accepted methods of karst aquifer investigation, could be rather misleading when applied to conduit aquifers.
Interactions between ice and groundwater were observed at two scales: regulation water appeared to feed a diffuse percolation system and supraglacial melt passed into subglacial conduits which entered open vadose shafts. Karst is unlikely to be entirely subglacial in origin because of the limited aggressiveness of subglacial waters.
The Castlegaurd karst appeared to have originated preglacially in response to the breaching of impermeable caprock. Glaciation re-ordered the landscape and produced abundant clastic debris which subsequently blocked or obstructed karst conduits. Much of the resulting karst is paragenetic and comparatively immature due to glacial disruption and slow growth rates. Geomorphic and hydrologic interactions between ice and karst depend intimately upon the relationship between the geographic zones of the glacier and the aquifer.


Further Studies at the Blue Waterholes, Cooleman Plain, N.S.W., 1969-77, Part I, Climate and Hydrology, 1983, Jennings, J. N.

Previous study of the temporal and spatial distribution of limestone solution at Cooleman Plain rested on monthly discharges and water analyses of the Blue Waterholes over 4 years. For this study automatic recording of discharge (8 years), rainfall (8 years), evaporation (7 years) and temperature (4 years) was attended by variable success in the face of interference, rigorous climate and inaccessibility. The most important aspect of the climatic data was the support obtained for the earlier assumption of similar water balances in the forested igneous frame and the grassland limestone plain. Runoff was again shown to be highly variable from year to year and to have an oceanic pluvial regime, with a summer-autumn minimum owing much to evapo-transpiration. The flow duration curve from daily discharges puts this karst amongst those where neither extremely high nor low flows are important. The stream routing pattern offsets the effect of 71% of the catchment being on non-karst rocks, damping flood events. An inflection of 700 l/s in a flow duration plot based on discharge class means is interpreted as the threshold at which surface flow down North Branch reaches the Blue Waterholes. Storages calculated from a generalised recession hydrograph parallel Mendip data where baseflow (fissure) storage provides most of the storage and quickflow (vadose) storage only a secondary part. Water-filled conduit storage (the phreas) could not be determined but is considered small. The baseflow storage seems large, suggesting that it can develop independently of caves in some measure. A quickflow ratio for floods derived by Gunn's modification of the Hewlett and Hibbert separation line method appears relatively low for a mainly non-karst catchment and is again attributed to the routing pattern. For analysis of variation of the solute load over time, estimates of daily discharge during gaps in the record where made for the author by Dr. A.J. Jakeman and Mr. M.A. Greenaway (see Appendix). A small number of discharge measures of two contrasted allogenic catchments of the igneous frame shows a unit area yield close to that for the whole catchment. Together with the guaging of most of the allogenic inputs, this supports the idea that the water yield is much the same from the forested ranges and the grassland plain. This is important for the estimation of limestone removal rates.


KARST SPRINGS HYDROGRAPHS AS INDICATORS OF KARST AQUIFERS, 1993, Bonacci O,
By analysing the hydrographs of karst springs it is possible to identify aquifer characteristics and, accordingly, the main features of a karst rock-fissure massif. Consequently, relevant data can be obtained by analysing hydrograph recession curves. This paper presents a detailed analysis and explanation of numerous cases of break points on recession curves via various values of the recession coefficient alpha in Maillet's (1905) equation. The paper also identifies the relationship between alpha and a linear reservoir coefficient by employing groundwater hydrograph methods. It is shown that the linear reservoir coefficient changes with time in accordance with changes of the flow conditions in the karst massif

The astronomical theory of climate and the age of the Brunhes-Matuyama magnetic reversal, 1994, Bassinot Fc, Labeyrie Ld, Vincent E, Quidelleur X, Shackleton Nj, Lancelot Y,
Below oxygen isotope stage 16, the orbitally derived time-scale developed by Shackleton et al. [1] from ODP site 677 in the equatorial Pacific differs significantly from previous ones [e.g., 2-5], yielding estimated ages for the last Earth magnetic reversals that are 5-7% older than the K/Ar values [6-8] but are in good agreement with recent Ar/Ar dating [9-11]. These results suggest that in the lower Brunhes and upper Matuyama chronozones most deep-sea climatic records retrieved so far apparently missed or misinterpreted several oscillations predicted by the astronomical theory of climate. To test this hypothesis, we studied a high-resolution oxygen isotope record from giant piston core MD900963 (Maldives area, tropical Indian Ocean) in which precession-related oscillations in [delta]18O are particularly well expressed, owing to the superimposition of a local salinity signal on the global ice volume signal [12]. Three additional precession-related cycles are observed in oxygen isotope stages 17 and 18 of core MD900963, compared to the composite curves [4,13], and stage 21 clearly presents three precession oscillations, as predicted by Shackleton et al. [1]. The precession peaks found in the [delta]18O record from core MD900963 are in excellent agreement with climatic oscillations predicted by the astronomical theory of climate. Our [delta]18O record therefore permits the development of an accurate astronomical time-scale. Based on our age model, the Brunhes-Matuyama reversal is dated at 775 10 ka, in good agreement with the age estimate of 780 ka obtained by Shackleton et al. [1] and recent radiochronological Ar/Ar datings on lavas [9-11]. We developed a new low-latitude, Upper Pleistocene [delta]18O reference record by stacking and tuning the [delta]18O records from core MD900963 and site 677 to orbital forcing functions

RELATIVE IMPORTANCE OF BASEFLOW AND QUICKFLOW FROM HYDROGRAPHS OF KARST SPRING, 1994, Padilla A. , Pulidobosch A. , Mangin A. ,
Evaluation of recession hydrographs, from four karst springs in Europe, provides important information concerning the flow process operating in karst aquifer systems. Three analytic equations are used to evaluate the hydrographs: Mangin's equation, that assumes the recession is composed of both quickflow and baseflow; Coutagne's equation which considers the recession to be the response of a single reservoir; and a new function, H(t) (which is derived from Coutagne's equation), that refers to the whole recession curve. Using Mangin's equation it is apparent that the saturated zone and thus baseflow exerts nearly complete control over the discharge of La Villa spring and is fairly important at Fuente Mayor and Baget springs, but is much less significant at Aliou spring. The saturated zone accounts for 100%, 90%, 91%, and 40% respectively for these springs. Using Coutagne's equation and H(t) it is concluded that for Aliou and Baget springs, water flows freely in the high transmissive zones, but in the poorly transmissive zones, there is little continuity of connection in the system. At Fuente Mayor spring the differences in these zones are not so apparent and a gradual transition occurs. However, at La Villa spring, the karst aquifer is evidently much more homogeneous and the discharge is similar to that of a porous intergranular aquifer

HYDROLOGIC RESPONSE OF A KARST WATERSHED, 1994, Felton Gk,
A ground water catchment was instrumented as a karst hydrology and water quality laboratory to develop long-term flow and water quality data. This catchment located in Woodford and Jessamine Counties in the Inner Bluegrass, Central Kentucky encompasses approximately 1620 ha, 40 water wells, over 400 sinkholes, 2 karst windows, and 1 sinking stream. The land uses consist of approximately 59% beef pasture, horse farm, and golf course; 16% row crops; 6% orchard; 13%forest; and 6% residential. The instrumentation consisted of a recording rain gage, an H-flume, a water stage recorder, and an automated water sampler. Flow data for 312 days were analyzed, and a peak flow rate prediction equation, specific to this catchment, was developed Recession curves were analyzed and found to be of two distinct mathematical forms, log curves and exponential curves. Prediction equations were good for the log-type recession curve and fair for the exponential-type recession curve. For the exponential recessions, the peak flow rate was found to be bimodally distributed The recession events were classified as either high flow or low flow, with the point of separation at 113 L/s. It was hypothesized that the flow system was controlled by pipe flow above 113 L/s and by open channel flow below 113 L/s. Subsequent analysis resulted in adequate prediction for the low flow events. Explained variation associated with the high flow events was low and attributed to storage in the karst system that was not incorporated into the predictor equation

IMPACT OF AN EXCEPTIONAL STORM EPISODE ON THE FUNCTIONING OF KARST SYSTEM - THE CASE OF THE 22/9/92 STORM AT VAISON-LA-ROMAINE (VAUCLUSE, FRANCE), 1995, Lastennet R. , Mudry J. ,
Karstification is a slow geodynamical process, controlled by the interaction between dissolution kinetics and flow dynamics. Moreover, mechanisms of network clogging by calcite precipitation or non-soluble clay accumulation are slow and continuous phenomena. This evolution of a karst system can be widely modified during exceptional rainfall episodes, such as the 22/09/92 storm (> 300 mm) near Vaison-la-Romaine. Such an impulse can modify the hydraulical behaviour of a massif, by unclogging the outlets of the saturated zone or the drainage network of the aquifer, and change hydrodynamical features of a spring (storage capacity etc.). This phenomenon has been demonstrated in a north Vaucluse karst aquifer whose recession coefficient has increased 7-fold and stored volume divided by 6

Nickpoint recession in karst terrains: An example from the Buchan karst, southeastern Australia, 1996, Fabel D, Henricksen D, Finlayson Bl, Webb Ja,
Nickpoint recession in the Buchan karst, southeastern Australia, has resulted in the formation of an underground meander cut-off system in the Murrindal River valley. Three nickpoints have been stranded in the surface channel abandoned by the subterranean piracy, and these can be correlated with river terraces and epiphreatic cave passages in the nearby Buchan River valley. The presence of palaeomagnetically reversed sediments in the youngest cave passage in the Buchan valley implies that the topographically lowest nickpoint in the Murrindal valley is more than 730 ka old, and the other nickpoints are probably several million years old. The nickpoints are occasionally active during floods, but the diversion of most surface flow underground has slowed down their retreat to the extent that they have been effectively stationary for several million years Underground nickpoint migration has been by both incision within major phreatic conduits and their abandonment for lower-level passages. The nickpoints are all present in the upstream part of the cave system, but have not migrated past the sink in the river channel, despite the long period of time available for this to happen. The sink is characterized by collapsed limestone blocks; these filter out the coarse bedload from the river channel. As a result, erosion within the cave passages is dominantly solutional and therefore slower than in the surface channel, where it is mostly mechanical. In addition, to transmit a drop in base level the cave system requires the removal of a larger volume of rock than for the surface migration of a nickpoint, because any roof collapse material in the subsurface system must be removed. These factors have slowed the migration of the base-level changes through the subsurface system, and may be a general feature in caves that have diffuse sinks as their main inputs

The influence of climatic change on exposure surface development: a case study from the Late Dinantian of England and Wales, 1996, Vanstone Simon,
Exposure surfaces represent an integral part of Asbian-Brigantian cyclothemic platform carbonates in England and Wales. These are characterized by the association of clay palaeosols, calcrete and palaeokarst and in most instances would appear to have been polygenetic. Alternating calcrete-karst stratigraphies associated with individual exposure surfaces indicate that the climate changed from semi-arid to humid to semi-arid conditions during each sea-level fall/rise cycle. Lowstand intervals were humid and resulted in karstification of the cyclothem-top sediments and the formation of a mineral soil. In contrast, regressive/transgressive phases were semi-arid and resulted in calcretization of the emergent platform carbonates. The influence that climatic cyclicity had upon exposure surface development was modulated by variations in platform bathymetry, subsidence and spatial climatic variation, and platforms exhibit their own individual record of what was essentially an idealized sequence of events. As with the sea-level oscillations responsible for cyclothemic sedimentation, the climatic cyclicity is thought to be the product of orbital forcing and probably reflects either eccentricity-driven shifts in the locus of monsoonal precipitation, or precession-driven variations in monsoonal intensity. If precessional in origin, exposure surface development represents a single minimum to minimum excursion, some 20 ka in duration, whereas if eccentricity-driven this may have been appreciably longer. Nevertheless, the immature nature of the exposure surfaces suggests that emergence was probably only of the order of a few tens of thousands of years

Analysis of well hydrographs in a karst aquifer: Estimates of specific yields and continuum transmissivities, 1996, Shevenell L. ,
Hydrograph analysis techniques have been well developed for hydrographs obtained from streams and springs, where data are cast in terms of total discharge. The data obtained from well hydrographs provide water level versus time; hence, a method of hydrograph analysis is required for situations in which only water level data are available. It is assumed here that three segments on a recession curve from wells in a karst aquifer represent drainage from three types of storage: conduit (C), fracture (F) and matrix (M). Hydrographs from several wells in a karst aquifer are used to estimate the specific yields (S-y) associated with each portion of the aquifer (C, F, M), as well as continuum transmissivities (T). Data from three short injection tests at one well indicate continuum rat this well bore is approximately 5 m(2) day(-1), and tests at numerous other wells in the aquifer yield results between 1 and 7 m(2) day(-1). The T estimated with well hydrographs from two storms indicates a T of 9.8 m(2) day(-1). Well-developed conduit systems in which water levels in wells show a flashy response typically show S(y)s of 1 x 10(-4), 1 x 10(-3), and 3 x 10(-3) for C, F, and M, respectively. Less well-developed conduit areas show more nearly equal S(y)s (8.6 x 10(-4), 1.3 x 10(-3), 3 x 10(-3)). Areas with no evidence for the presence of conduits have only one, or in some cases two, slopes on the recession curve. In these cases, water-level responses are slow. Recession curves with a single slope represent drainage from only the lower T matrix. Those with two slopes have an additional, more rapid response segment on the recession curve which represents drainage from the higher T, lower S-y, fractures in the system

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