Showing papers in "Hydrological Sciences Journal-journal Des Sciences Hydrologiques in 1969"
TL;DR: In this article, various models were proposed for giving the value of the storage coefficient from field measurements of piezometric levels, rainfall, geophysical and granulometric characteristics obtained during pump tests in the alluvionnal aquifer of the Rhin valley.
Abstract: Various models were proposed for giving the value of the storage coefficient from field measurements of piezometric levels, rainfall, geophysical and granulometric characteristics obtained during pump tests in the alluvionnal aquifer of the Rhin valley. Values obtained by the various methods agreed relatively well, thus indicating the uselfulness of these techniques.
40 citations
TL;DR: In this paper, a pore-volume probability density function is introduced which permits the development of a function for describing effective saturation in terms of dimensionless capillary pressure p e, that is, capillary pressures scaled in the terms of bubbles.
Abstract: Synopsis The equations of Brooks and Corey for relating effective saturation S e to capillary pressure p e describe experimental data quite well for small values of S e but overestimate p e as S e approaches unity. Using assumed functions for the distribution of pore volume with respect to pore radius, Brutsaert was able to describe experimental data satisfactorily provided that constants such as mean pore radius and the standard deviation of pore radius were determined from distribution functions derived from experimental data rather than from the assumed functions. White developed a mathematical model which described experimental data of S(p e ) satisfactorily but the technique required the determination of thirteen constants describing the relationship. In this paper, a pore-volume probability density function is introduced which permits the development of a function for describing effective saturation in terms of dimensionless capillary pressure p e , that is, capillary pressure scaled in terms of bub...
34 citations
TL;DR: In this article, it is shown that not only does topography affect the actual rainfall distribution, but also the areal variability, measured as the correlation between any two points, is also dependent on the relief.
Abstract: Synopsis In areas of accentuated relief, some of the basic assumptions made in the use of standard methods of assessing areal mean rainfall are often untenable. It is shown in this paper, that, not only does topography affect the actual rainfall distribution, but that the areal variability, measured as the correlation between any two points, is also dependent on the relief. Two methods are used to show this. Once method compares the areal variability of a flat area to one of accentuated relief, while the second method relates areal variability to topographic factors using a multiple regression technique. The conclusions reached are then used for three purposed. The first is to develop a method of ascribing objectively areas or points to a particular raingauge, taking into account the nature of the terrain. The second is to establish a procedure for estimating the rainfall at ungauged points, by taking into account the rainfall at a selected nearby rainguage and the topographic situation of the points, and...
31 citations
TL;DR: In this article, a resistivity survey in Wenner arrangement has been conducted in the water-table aquifer in the eastern part of the Coastal Area of Belgium, where Bore holes have been drilled to test the geoelectrical data and also to collect water samples.
Abstract: A resistivity survey in Wenner arrangement has been conducted in the water-table aquifer in the eastern part of the Coastal Area of Belgium. Bore holes have been drilled to test the geoelectrical data and also to collect water samples. The chemical characteristics and the distribution of different water types explain the hydrochemistry of the water-table aquifer. The fresh-/brackish-water boundary as determined by the resistivity survey has been expressed in terms of total dissolved-solids content.
27 citations
TL;DR: In this paper, the authors put emphasis on the combined influence of the climate, nature of rock and geological structure on the occurence, flow and quality of the groundwater and explained the difference and similarities between the hydrogeological regime of different provinces.
Abstract: Summary The hydrogeological character of the various provinces of Iran is treated in the following paper. The author puts emphasis on the combined influence of the climate, nature of rock and geological structure on the occurence, flow and quality of the groundwater and explains the difference and similarities between the hydrogeological regime of the different provinces. Four main and distinct hydrogeological provinces are described: 1) The Central Plateau. 2) The Zagros mountain ranges. 3) The Caspian Coastal Plain. 4) The Alborz mountains.
27 citations
TL;DR: In this paper, the authors discuss the specific problems dealing with the use of Americium 241 for measuring the water content of soil sample by attenuation of low-energy gamma rays.
Abstract: The purpose of this paper is to discuss the specific problems dealing with the use of Americium 241 for measuring the water content of soil sample by attenuation of low energy gamma rays. One of the advantages is that the optimum thickness of the soil sample is about 4 to 5 cm. However, one of the difficulties encountered is related to the determination of the absorption coefficient, which is generally lower than the theoretical value. Special attention is drawn to the problems of counting losses in the gamma spectrometer system. Experimental results are presented showing the importance of the system geometry.
21 citations
TL;DR: In this paper, the non-Darcian behavior of water in soils is discussed considering the coupling that can arise between the different transport phenomena, and it is shown that there is a reason to expect that a difference in osmotic pressure will arise when solutions flow through porous media, and that due to that difference the resulting flow be related in a nonlinear fashion to the applied pressure difference.
Abstract: The “non-Darcian” behaviour of water in soils is discussed considering the coupling that can arise between the different transport phenomena. In general, it is shown that there is a reason to expect that a difference in osmotic pressure will arise when solutions flow through porous media, and that due to that difference the resulting flow be related in a non-linear fashion to the applied pressure difference. Several numerical examples are presented illustrating this behaviour.
19 citations
TL;DR: In this article, the conection between surface and ground water is emphasized and the operational plan to solve or to avoid these problems is described This plan includes combined use of surface and sub-surface reservoirs for water concervation.
Abstract: Summary The geological and hydrological caracteristics of the ground-water reservoirs used for the Barcelona water suply are described. The conection between surface and ground water is emphasized. Ground water meets about 50% of the courrent water demands for water suply to Barcelona Metropolitan area (500 hm3 for year or 360 MGD). Present and future problems such as water pollution and water shortage, legal cuestions and education are briefty touched upon. Finally the operational plan to solve or to avoid these problems is described This plan includes combined use of surface and sub-surface reservoirs for water concervation.
8 citations
7 citations
TL;DR: In this paper, a battery of evapotranspirators was used to measure the CO2 content of the air made inside and outside the evapots, and a close correlation between CO2 and water vapor fluxes (computed by means of mass transfer equations) above the saltcedar thickets.
Abstract: Near Buckeye, Arizona, saltcedar (Tamarix pentandra) was grown on a battery of evapotranspirometers under various conditions of plant density, soil salinity, and access to water. Growth and development of these plants declined sharply at the beginning of each July, although before that time rates of growth and development had been very high. It was initially postulated that carbon dioxide might have become the limiting factor. Measurements of CO2 content of the air made at different heights inside and outside the evapotranspirometers, however, showed that this was not the case. Analysis of the data shows a close correlation between CO2 and water vapor fluxes (computed by means of mass transfer equations) above the saltcedar thickets. A reduction in fluxes during hot afternoons appears to be due to ambient temperatures over 40°C. Water use is similarly affected.
7 citations
TL;DR: In this article, a summary of the mechanisms of dispersion of miscible contituents in the liquid phase of porous materials is presented, and the transport is considered from both a microscopic (within the pore spaces) and macroscopic (an average of a representative number of pores) point-of-view.
Abstract: Synopsis A summary is presented on the mechanisms of dispersion of miscible contituents in the liquid phase of porous materials. The transport is considered from both a microscopic (within the pore spaces) and macroscopic (an average of a representative number of pores) point-of-view. An attempt has been made to point out some of the problems associated with the use of the physically measurable macroscopic variables when investigating the basically microscopic phenomenon of dispersion. Some simple reactions between soil materials and chemical substances are discussed and some applications to tracer studies are presented.
TL;DR: In this paper, a computer program written for a Univac 1108 and the use of its "control" cards for the analysis of glacier inventory data from a test area in the Canadian Arctic (Axel Heiberg Island) is outlined.
Abstract: Based on the I.H.D. Resolution 1–12 the Commission of Snow and Ice of the I.A.S.H. prepared guide lines for the recording and mapping of the worldwide distribution, water equivalent and related data of 1) the total seasonal snow cover, 2) the sea, lake and river ice, and 3) the perennial ice and snow masses on and beneath the land surfaces. Using the glacier inventory as an example, the problems of standardization and presentation of data are discussed. The operation of a computer program written for a Univac 1108 and the use of its ‘control’ cards for the analysis of glacier inventory data from a test area in the Canadian Arctic (Axel Heiberg Island) is outlined. The program presently sorts according to characteristics and classification numbers. A range of variables may be chosen and any one variable is averaged, totalled or histogrammed as instructed by the control cards. A brief description of the program is included. The development of a second stage to the program is envisaged.
TL;DR: In this article, the concept of specific yield as applied to unconfined aquifers is discussed, and it is shown that the value of the true specific yield is generally a function of both horizontal position and time.
Abstract: The concept of the specific yield as it is applied to unconfined aquifers, is discussed, and it is shown that the value of the true specific yield is generally a function of both horizontal position and time. Because of the difficulties associated with the measurement of localised fluxes and localised water-table movements necessary to obtain values of the true specific yield, the average, the bulk and the virtual specific yields are defined, all of which are just time dependent and the last two of which require the measurement of average fluxes over the catchment area. The non-constancy of the specific yield is illustrated in experimental results obtained with intermittent rainfall over a drainage installation where negative values were obtained, reaching ±∞ when the water-table height was a maximum or minimum.
TL;DR: In this paper, a two-dimensional soil model is proposed for obtaining a complete description of the variation of water-content, water fluxes and pressure during unsteady conditions of drainage and recharge.
Abstract: An attempt has been made to consider as a whole the flow of water in both saturated and unsaturated zones. It is indeed clear that the position of the water table, when considering the hydrodynamics of free surface aquifers, must be controlled by the flow occuring in the unsaturated zone (evaporation, recharge, etc…). A system of two differential equations—each one related to the saturated and unsaturated zone—is proposed for defining the position of the water table. This replaces the unique classical BOUSSINESQ equation, which is obtained by considering the free surface as the upper boundary of the flow domain. In view of experimental results obtained from the drainage of vertical column of soils, a critique of classical analogue models is made. A two-dimensional soil model is then proposed for obtaining a complete description of the variation of water-content, water fluxes and pressure during unsteady conditions of drainage and recharge. Measurements of changes of water content and pressures wi...
TL;DR: In this article, the entrapment mecanisms are poorly known and experimental results do not match satisfactorily with the diffusivity or continuum mecanics theories which do not take the entrapped gas phase into account.
Abstract: In porous media, entrapped gas is considered as an important factor reducing the transmissibility of fluids through the medium. Because entrapment mecanisms are poorly known and entrapped gas content is a function not only of water content but also of time due to the gas solubility, experimental results do not match satisfactorily with the diffusivity or continuum mecanics theories which do not take the entrapped gas phase into account. Measurement of entrapped gas content are presented together with the corresponding water content hysteresis isotherm.
TL;DR: An inexpensive continuously recording turbidity transducer on two different types of mounting has been developed at the University of Natal, and installed at two stations in the Umgeni River system as mentioned in this paper.
Abstract: Synopsis An inexpensive continuously recording turbidity transducer on two different types of mounting has been developed at the University of Natal, and installed at two stations in the Umgeni River system. The geometry and components of the transducers are detailed, and a sampler used to calibrate the transducers is also described. A portable turbidity meter has also been developed.
TL;DR: In this article, the problem of determining the rate of recharge per unit area from a terrain situated a few hundred metres from the mine workings and in this connection the velocity of flow.
Abstract: The control of karstic water inrush presents continuous difficulties at the Dorog coal-mines in the north-western part of Hungary. The efforts to control water inrush call for continuous research work. The problem was to determine the rate of recharge per unit area from a terrain situated a few hundred metres from the mine workings and in this connection the velocity of flow. Fluorescein was used as tracer material which was introduced through a borehole into the waterbearing formation. Samples were retrieved from water which entered the mine at several points. The tracer material was observed first 49 days after introduction, at a point of inrush situated 426 m distant from the point of introduction, i.e., the borehole (fig. 1). Calculations of flow velocity were based on the geometry pattern of a single point sink, or flow towards this sink. Basic criteria were the velocity computed on the basis of straight-line flow and the constant discharges at the point of inrush and introduced into the bor...
TL;DR: In this paper, the effective porosity of partially penetrated aquifers was determined for the model basin sandy aquifer available in the Centre of the USA and the results were in good agreement with the adopted values.
Abstract: The effective porosity θ e for partially penetrated aquifers was determined. The model basin sandy aquifer available in the Centre was used. The values obtained for θ e were in good agreement with the adopted values.
TL;DR: In this article, the authors defined the interstitial pressure and the suction for sands and clays, and considered the general aspect of experimental measurements of interstitialpressure with tensiometers, taking into account the apparatus characteristics, and the properties of the materials.
Abstract: We first define the interstitial pressure and the suction for sands and clays. Due to differences in behaviour of these two types of soils, the general equations for flow will be different. Next, we consider the general aspect of experimental measurements of interstitial pressure with tensiometers, taking into account the apparatus characteristics, and the properties of the materials. One of the most important conclusion is as follows: the response time of the apparatus and of the whole system are functions of the soil conductivity and of the slope of the moisture characteristics. Moreover, the response time is not a constant; it is thus quite difficult to make corrections in tensiometer measurements.
TL;DR: In this paper, the authors give data of water infiltrations in horizontal and vertical columns, and in a two dimensional model, and the characteristics of these soils are given in the article.
Abstract: The authors give data of water infiltrations in horizontal and vertical columns, and in a two dimensional model. The soils are two mixtures of sand and loam, and a natural sandy loam. The characteristics of these soils are given in the article. As a conclusion, the two dimensional problem can be approached by a linear combination of data in horizontal and vertical columns.
TL;DR: In this article, the forecast method is the least squares multiple regression, based on the observations of more than 50 years, and the largest errors of forecast were encountered in thawing conditions.
Abstract: Summary Forecasts of the discharge of the Rhine at Basel have been studied in Zurich since 1954. In this programme have cooperated hydro-power companies of Switzerland, Germany and France, French shipping-firms, and the Dutch water management authorities. For the Netherlands the forecast of the summer yield of the Rhine is of great concern, since it is the main resource of fresh water. The studies have resulted in: — since 1955, annual forecasts of the yield from snowmelt for periods of one to eight months beginning with March, and monthly and bi-monthly forecasts in winter — since 1960, forecasts issued 2 to 5 times per week for the next three days, from October to March. The forecast method is the least squares multiple regression, based on the observations of more than 50 years. For the short term forecasts, the significant predictors are discharge and rainfall, eventually the snow cover percentage on the Swiss midland plateau. The largest errors of forecast were encountered in thawing conditions. Mete...
TL;DR: In this article, the response time τ = (1/K′ S) of the system: porous cup (conductance K') and manometer (sensitivity S) can be improved by taking into account the elasticity of the tubing by analogy one can appreciate the role of entrapped air in the circuit.
Abstract: The interpretation of tensiometers measurements requires special knowledge of the mechanics of equilibrium of the tensiometer with its environment The classical concept of response time τ = (1/K′ S) of the system: porous cup (conductance K') and manometer (sensitivity S) can be improved by taking into account the elasticity of the tubing By analogy one can appreciate the role of entrapped air in the circuit In general, it is possible to theorically observe the response characteristics of the tensiometer by imposing pressure step in the system and by studying the equilibrium response Such tests showed certain anomalies of behaviour which can be attributed to very small bubbles of air entrapped to the internal wall of the porous cup However, it is necessary to check the response of the tensiometer when it is placed in the soil This is confirmed by analysis and experiments in a sandy and clayed soils
TL;DR: In this article, the behavior of unsaturated porous materials is described according to the procedure of FICK'S mixture theory, and hysteresis is included by use of the VOLTERRA'S integral form or by an approximative method using experimental results.
Abstract: Summary The behaviour of unsaturated porous materials is described according to the procedure of FICK'S mixture theory. Hysteresis is included by use of the VOLTERRA'S integral form or by an approximative method using experimental results. Several mathematical models corresponding to physically significant situations are derived from the theory.
TL;DR: In this article, the apparent change in height of the horizon over a lake will be a useful measure of the atmospheric stability, i.e. of the difference in temperature of the water and the air over it.
Abstract: It is suggested that the apparent change in height of the horizon over a lake will be a useful measure of the atmospheric stability, i.e. of the difference in temperature of the water and the air over it.