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Determination of seepage parameters from data of a quick water intakke test and solution of the Boussinesq equation
274A
HYDROGEOLOGY:GROUNDWATER
certain adverse effects on the natural environment. This paper deals with all of these subjects. -Author 946088 Study on variation of aquifer rock parameters by water level response to earth tide (in Chinese) Chen Jianming, Zhang Zhaodong, Yang Linzhang, Shi Ronghui & Zhang Jihong, Earthquake (Beijing), 1, 1994, pp 73-78. The relationship between the water level of artesian wells and the body strain of aquifer's tide, as well as the water level response to the earth tide under the non-linear instability, are theoretically discussed. The variation of response rate and response ratio are also discussed. The computation and analysis of water level data indicate that the response rate showed some changes before earthquakes and the background value of response ratio is I. It is identical with the theoretical value and also showed some changes before earthquakes. This demonstrates that the water level response to the solid tide might reflect some variation of aquifer's parameters. -English summary 946089 Architecture and directional scales of heterogeneity in alluvial-fan aquifers M . J . Neton, J. Dorsch, C. D. Olson & S. C. Young,
Journal of Sedimentary Research B: Stratigraphy Global Studies, B64(2), 1994, pp 245-257.
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Alluvial fans are directional landforms that extend downdip from a point source. Grain size and bed thickness generally decrease down fan. Abrupt to gradational facies relationships change down fan and may be substantially different m adjacent fans. Hydrologic properties may parallel the down-fan fining trend or may show a 'humped'pattern in a down-fan direction. As fans subside, prograde, and retrograde, a directional a.quifer is created whose complex heterogeneities require a drrectional model. The directional alluvial-fan aquifer is best characterized by three directional scales of heterogeneity (from smallest to largest): 1) within-fan, 2) between-fan and 3) cross-fan. A directional view of heterogeneities in alluvial-fan aquifers is essential for correct site characterization and for design of well networks, aquifer tests, and flow models. -from Authors 946090 Determination of seepage parameters from data of a quick water intake test and solution of the Boussinesq equation A. R. Kasimov & A. V. Lapin, Hydrotechnical Construction, 27(I0), 1994, pp 600-607; translated from: Gidrotekhnicheskoe Stroitel'stvo, 10, 1993, pp 36-40. A mathematical procedure is proposed for determining seepage parameters of an aquifer. These included the storage coefficients of a dry bed as an aquiclude, leakage of this bed underlain by a low-permeabihty interlayer and the gravitational storage of a saturated bed. Typical calculations are carried out using this procedure. -P.M.Taylor
946091 Calibration of dual-energy gamma systems for determining liquid saturations during multiphase flow in soil K . M . Bali & M. E. Grismer, International Agrophysics, 8(1), 1994, pp 1-8. The purpose of this study was to calibrate a dual-energy gamma system for simultaneous determination of aqueous and non-aqueous phase liquid (NAPL) saturations m soil columns. A dual-energy gamma system containing 241Am and la7Cs was used to study the infiltration and displacement of aqueous liquid by NAPL and vis versa. Distilled water, NaI solution, and Soltrol 130 were used as fluids. The system was calibrated to minimize errors in liquid saturations due to the random nature of gamma photons emission and drift in the photon detection equipments. The measurement accuracy in liquid saturations was substantially improved by increasing counting time and fluid attenuation coefficient. NaI salt was used to increase the attenuation coefficient of water. Measured and predicted liquid saturations during immiscible displacement in soil were consistent with mass balance measurements and anticipated deviations in saturations from probable error calculations. The calibration procedure resulted in a significant improvement in the prediction of liquid saturations using dual-energy gamma systems. -Authors
946092 Influence of seepage tlow on the passive earth pressures A. H. Soubra & R. Kastner, in: Retaining, structures Proc. conference, Cambridge, 1992, ed CR I Clayton, (Thomas Telford), 1993, pp 67-76. Upward seepage forces cause instability of sheet piling structures by the reduction of the passive earth force. Our aim in this paper is to propose an outline for the calculation of the passive earth pressures, taking into account the seepage forces. Traditionally, the determination of these pressures is made using the classical method introduced by Terzaghi. In this paper, we present a more rational method which allows a rigorous solution of the earth pressure, taking into consideration the seepage forces. This method is based on a variational approach. It is a rigorous one in regard to the limit equilibrium method as it makes no assumptions with respect to the shape of the slip surface and the normal stress distribution along this surface. The variational limit equilibrium method is equivalent to the upper-bound method in limit analysis for a rotational logspiral mechanism, hence the solution obtained is an upperbound one for a rigid perfectly plastic material obeying Hill's maximal work principle, from Authors 946093 Optimal ground water pumping model A. Wita & A. Czachowska-Aussenberg, Archives of Hydroengineering, 40(3-4), 1994, pp 51-66. The paper presents possibilities of application of linear programming to optimize water pumping from an aquifer using vertical wells. An optimization model is described, in which so-called 'response coefficients' characterizing lowering of the ground water table in some points of the aquifer, resulting from unit water discharge from individual wells, are used. The results of application of the optimization model to the problem of dry dock dewatering are presented. To verify the optimal solution resulting from the model, a forecast of ground water level changes has been calculated. -from Authors 946094 Geochemical evolution of groundwater in the Culebra Dolomite near the Waste Isolation Pilot Plant, southeastern New Mexico, USA M. D. Siegel & S. Anderholm, Geochimica et Cosmochimica Acts, 58(10), 1994, pp 2299-2323. The Culebra Dolomite Member of the Rustler Formation, a thin fractured dolomite aquifer, lies approximately 450 m above the repository horizon of the Waste Isolation Pilot Plant. A proposed model for the post-Pleistocene hydrochemical evolution of the Culebra tentatively identifies the major sources and sinks for many of the groundwater solutes. The results of the geochemical calculations and mineralogical data are consistent with the following hydrochemical model: 1) solutes are added to the Culebra by dissolution of evaporite minerals; 2) the solubilities of gypsum and calcite increase as the salinity increases; 3) equilibrium is not maintained between the waters and dolomite; sufficient Mg is added to the waters by dissolution of accessory camallite or polyhalite such that the degree of dolomite supersaturation increases with ionic strength; and 4) clays within the fractures and rock matrix exert some control on the distribution of Li, B, Mg, and Si via sorption, ion exchange, and dissolution. -from Authors 946095 A three-dimensional multiphase flow model for assessing NAPL contamination in porous and fractured media, 1. Formulation P. S. Huyakorn, S. Panday & Y. S. Wu, Journal of Contaminant Hydrology, 16(2), 1994, pp 109-130. A three-dimensional, three-phase numerical model is presented for simulating the movement of non-aqueousphasc liquids (NAPL's) through porous and fractured media. The model formulation is first derived for threephase flow of water, NAPL and air in porous media. The formulation is then extended to handle fractured systems using the dual-porosity and discrete-fracture modeling approaches. The model accommodates a wide variety of boundary conditions, including withdrawal and injection well conditions which are treated rigorously using fully implicit schemes. -from Authors
HYDROGEOLOGY:GROUNDWATER
certain adverse effects on the natural environment. This paper deals with all of these subjects. -Author 946088 Study on variation of aquifer rock parameters by water level response to earth tide (in Chinese) Chen Jianming, Zhang Zhaodong, Yang Linzhang, Shi Ronghui & Zhang Jihong, Earthquake (Beijing), 1, 1994, pp 73-78. The relationship between the water level of artesian wells and the body strain of aquifer's tide, as well as the water level response to the earth tide under the non-linear instability, are theoretically discussed. The variation of response rate and response ratio are also discussed. The computation and analysis of water level data indicate that the response rate showed some changes before earthquakes and the background value of response ratio is I. It is identical with the theoretical value and also showed some changes before earthquakes. This demonstrates that the water level response to the solid tide might reflect some variation of aquifer's parameters. -English summary 946089 Architecture and directional scales of heterogeneity in alluvial-fan aquifers M . J . Neton, J. Dorsch, C. D. Olson & S. C. Young,
Journal of Sedimentary Research B: Stratigraphy Global Studies, B64(2), 1994, pp 245-257.
&
Alluvial fans are directional landforms that extend downdip from a point source. Grain size and bed thickness generally decrease down fan. Abrupt to gradational facies relationships change down fan and may be substantially different m adjacent fans. Hydrologic properties may parallel the down-fan fining trend or may show a 'humped'pattern in a down-fan direction. As fans subside, prograde, and retrograde, a directional a.quifer is created whose complex heterogeneities require a drrectional model. The directional alluvial-fan aquifer is best characterized by three directional scales of heterogeneity (from smallest to largest): 1) within-fan, 2) between-fan and 3) cross-fan. A directional view of heterogeneities in alluvial-fan aquifers is essential for correct site characterization and for design of well networks, aquifer tests, and flow models. -from Authors 946090 Determination of seepage parameters from data of a quick water intake test and solution of the Boussinesq equation A. R. Kasimov & A. V. Lapin, Hydrotechnical Construction, 27(I0), 1994, pp 600-607; translated from: Gidrotekhnicheskoe Stroitel'stvo, 10, 1993, pp 36-40. A mathematical procedure is proposed for determining seepage parameters of an aquifer. These included the storage coefficients of a dry bed as an aquiclude, leakage of this bed underlain by a low-permeabihty interlayer and the gravitational storage of a saturated bed. Typical calculations are carried out using this procedure. -P.M.Taylor
946091 Calibration of dual-energy gamma systems for determining liquid saturations during multiphase flow in soil K . M . Bali & M. E. Grismer, International Agrophysics, 8(1), 1994, pp 1-8. The purpose of this study was to calibrate a dual-energy gamma system for simultaneous determination of aqueous and non-aqueous phase liquid (NAPL) saturations m soil columns. A dual-energy gamma system containing 241Am and la7Cs was used to study the infiltration and displacement of aqueous liquid by NAPL and vis versa. Distilled water, NaI solution, and Soltrol 130 were used as fluids. The system was calibrated to minimize errors in liquid saturations due to the random nature of gamma photons emission and drift in the photon detection equipments. The measurement accuracy in liquid saturations was substantially improved by increasing counting time and fluid attenuation coefficient. NaI salt was used to increase the attenuation coefficient of water. Measured and predicted liquid saturations during immiscible displacement in soil were consistent with mass balance measurements and anticipated deviations in saturations from probable error calculations. The calibration procedure resulted in a significant improvement in the prediction of liquid saturations using dual-energy gamma systems. -Authors
946092 Influence of seepage tlow on the passive earth pressures A. H. Soubra & R. Kastner, in: Retaining, structures Proc. conference, Cambridge, 1992, ed CR I Clayton, (Thomas Telford), 1993, pp 67-76. Upward seepage forces cause instability of sheet piling structures by the reduction of the passive earth force. Our aim in this paper is to propose an outline for the calculation of the passive earth pressures, taking into account the seepage forces. Traditionally, the determination of these pressures is made using the classical method introduced by Terzaghi. In this paper, we present a more rational method which allows a rigorous solution of the earth pressure, taking into consideration the seepage forces. This method is based on a variational approach. It is a rigorous one in regard to the limit equilibrium method as it makes no assumptions with respect to the shape of the slip surface and the normal stress distribution along this surface. The variational limit equilibrium method is equivalent to the upper-bound method in limit analysis for a rotational logspiral mechanism, hence the solution obtained is an upperbound one for a rigid perfectly plastic material obeying Hill's maximal work principle, from Authors 946093 Optimal ground water pumping model A. Wita & A. Czachowska-Aussenberg, Archives of Hydroengineering, 40(3-4), 1994, pp 51-66. The paper presents possibilities of application of linear programming to optimize water pumping from an aquifer using vertical wells. An optimization model is described, in which so-called 'response coefficients' characterizing lowering of the ground water table in some points of the aquifer, resulting from unit water discharge from individual wells, are used. The results of application of the optimization model to the problem of dry dock dewatering are presented. To verify the optimal solution resulting from the model, a forecast of ground water level changes has been calculated. -from Authors 946094 Geochemical evolution of groundwater in the Culebra Dolomite near the Waste Isolation Pilot Plant, southeastern New Mexico, USA M. D. Siegel & S. Anderholm, Geochimica et Cosmochimica Acts, 58(10), 1994, pp 2299-2323. The Culebra Dolomite Member of the Rustler Formation, a thin fractured dolomite aquifer, lies approximately 450 m above the repository horizon of the Waste Isolation Pilot Plant. A proposed model for the post-Pleistocene hydrochemical evolution of the Culebra tentatively identifies the major sources and sinks for many of the groundwater solutes. The results of the geochemical calculations and mineralogical data are consistent with the following hydrochemical model: 1) solutes are added to the Culebra by dissolution of evaporite minerals; 2) the solubilities of gypsum and calcite increase as the salinity increases; 3) equilibrium is not maintained between the waters and dolomite; sufficient Mg is added to the waters by dissolution of accessory camallite or polyhalite such that the degree of dolomite supersaturation increases with ionic strength; and 4) clays within the fractures and rock matrix exert some control on the distribution of Li, B, Mg, and Si via sorption, ion exchange, and dissolution. -from Authors 946095 A three-dimensional multiphase flow model for assessing NAPL contamination in porous and fractured media, 1. Formulation P. S. Huyakorn, S. Panday & Y. S. Wu, Journal of Contaminant Hydrology, 16(2), 1994, pp 109-130. A three-dimensional, three-phase numerical model is presented for simulating the movement of non-aqueousphasc liquids (NAPL's) through porous and fractured media. The model formulation is first derived for threephase flow of water, NAPL and air in porous media. The formulation is then extended to handle fractured systems using the dual-porosity and discrete-fracture modeling approaches. The model accommodates a wide variety of boundary conditions, including withdrawal and injection well conditions which are treated rigorously using fully implicit schemes. -from Authors