References of "Dassargues, Alain"
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See detailA new single well tracer test: the Finite Volume Point Dilution Method. Theory, field application and model validation
Brouyère, Serge ULg; Batlle Aguilar, Jordi ULg; Goderniaux, Pascal ULg et al

in Calibration and Reliability in Groundwater Modelling: Credibility in Modelling (Pre-Published Proc. of ModelCARE’2007) (2007)

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See detailIdentification and quantification of sources of major solutes in a sandy, phreatic aquifer in Central Belgium through ionic ratios and geochemical mass-balance modelling
Peeters, Luk; Batelaan, Okke; Dassargues, Alain ULg

in Groundwater and Ecosystems, Proc. of the XXXV IAH Congress (2007)

In this study the processes affecting groundwater chemistry in the Eocene Brussels sands aquifer in Central Belgium are identified based on evaluation of ionic ratios of major solutes. Based on these ... [more ▼]

In this study the processes affecting groundwater chemistry in the Eocene Brussels sands aquifer in Central Belgium are identified based on evaluation of ionic ratios of major solutes. Based on these results, in combination with mineralogical and hydrogeological information of the aquifer, a geochemical mass-balance model is created to quantify the contribution of each of the processes to the observed composition of groundwater. After a rigorous validation process, a dataset of 99 groundwater samples is obtained from observation and pumping wells in the Eocene Brussels sands aquifer, which is one of the main aquifers for drinking water production in Belgium. The aquifer consists of heterogeneous alteration of calcified and silicified coarse sands, with local presence of clay drapes and glauconite-rich zones (Laga et al. 2001). The entire aquifer is overlain by Quaternary eolian deposits, mainly consisting of loam with the exception of the north east, where the Quaternary deposits are sandy loam. The groundwater in this aquifer is of Ca-Mg-HCO3-type with locally elevated nitrate concentrations. Based on the evaluation of ionic ratios and the mineralogy of the aquifer, a conceptual geochemical model is developed for mass-balance modeling, including (1) concentration of precipitation by a factor 1 to 5 due to evaporation, (2) dissolution of a pure calcite phase and a calcite phase containing 25 % magnesium by both carbonic acid and sulfuric acid, (3) anthropogenic inputs for all major cations and anions except bicarbonate, (4) dissolution of glauconite, (5) cation exchange of sodium and potassium for calcium and magnesium. The two calcite phases can be thought of as end-members of a solid solution of magnesium in calcite. The mass-balance modeling consists of a mole-balance equation for each considered element according to: [Obs] = p[Prec] + p1[Phase 1] + ... + pi[Phase i] + a [Anthropogenic] +/- c[Cation Exchange] This set of linear equations is additionally constrained by (1) defining a range for concentration factors p based on measured and calculated evaporation rates, (2) charge balance for the anthropogenic sources and (3) pi being positive or negative according to whether the phase dissolves or precipitates. The set of linear equations with the given constraints is solved using a least squares optimization. Based on the possible processes and reactions several geochemical models are tested for each sample and a model is considered adequate if the root mean squared error (RMSE) between observed and calculated concentrations is less than 10-10 mol/L and the charge balance of the calculated composition is less than 5 %. If several models are able to explain the observed concentrations, the RMSE provides an objective measure to compare the quality of the models. The best model for each sample is selected and the spatial distribution of these models is compared to the spatial variations in lithology and land-use to asses the feasibility of the proposed models. [less ▲]

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See detailCarte hydrogéologique de Wallonie, Hotton - Dochamps 55/5-6
Ruthy, Ingrid ULg; Dassargues, Alain ULg

Cartographic material (2006)

Detailed reference viewed: 144 (2 ULg)
See detailCarte hydrogéologique, Hotton - Dochamps 55/5-6, 1/25.000 : [notice explicative]
Ruthy, Ingrid ULg; Dassargues, Alain ULg

Book published by Ministère de la Région wallonne, Direction générale des ressources naturelles et de l'environnement - Edition provisoire : septembre 2006 (2006)

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See detailCarte hydrogéologique, Aye - Marche-en-Famenne 54/7-8, 1/25.000 : [notice explicative]
Ruthy, Ingrid ULg; Dassargues, Alain ULg

Book published by Ministère de la Région wallonne, Direction générale des ressources naturelles et de l'environnement - Edition provisoire : juillet 2006 (2006)

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See detailCarte hydrogéologique de Wallonie, Maffe - Grandhan 54/3-4, 1/25.000 : [notice explicative]
Ruthy, Ingrid ULg; Dassargues, Alain ULg

Book published by Ministère de la Région wallonne, Direction générale des ressources naturelles et de l'environnement - Edition provisoire : juillet 2006 (2006)

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See detailCarte hydrogéologique de Wallonie, Maffe - Grandhan 54/3-4
Ruthy, Ingrid ULg; Dassargues, Alain ULg

Cartographic material (2006)

Detailed reference viewed: 36 (2 ULg)
See detailCarte hydrogéologique de Wallonie, Aye - Marche-en-Famenne 54/7-8
Ruthy, Ingrid ULg; Dassargues, Alain ULg

Cartographic material (2006)

Detailed reference viewed: 35 (1 ULg)
See detailCarte hydrogéologique de Wallonie, Alleur - Liège 42/1-2
Ruthy, Ingrid ULg; Dassargues, Alain ULg

Cartographic material (2006)

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See detailSimulations MOHICAN pour la statistique des débits maxima (projet STATHY) : bassins de la Warchenne, la Wamme et la Gueule
Deliège, Jean-François ULg; Bourouag, Mohamed ULg; Smitz, Joseph ULg et al

Report (2006)

Le modèle MOHICAN (« Modèle hydrologique intégré pour le calcul des crues et l’amplitude des niveaux d’eau ») a été développé conjointement par l’Université de Liège (Laboratoire d’hydrodynamique ... [more ▼]

Le modèle MOHICAN (« Modèle hydrologique intégré pour le calcul des crues et l’amplitude des niveaux d’eau ») a été développé conjointement par l’Université de Liège (Laboratoire d’hydrodynamique appliquée, Laboratoire de Géologie de l’Ingénieur et d’Hydrogéologie, Centre d’Etude et de Modélisation de l’environnement) et la Faculté Universitaire des Sciences Agronomiques de Gembloux (Unité d’Hydraulique agricole) pour le compte et avec le support du Ministère de l’Equipement et des Transports, Service d’Etudes Hydrologiques (MET/SETHY) de la Région wallonne. Dans le cadre du projet STATHY visant à établir la cartographie des zones d’inondation en région Wallonne, il était nécessaire de disposer de séries étendues de débits horaires pour chaque sous-bassin versant. Le modèle MOHICAN a été utilisé à la demande du SETHY pour générer ces données sur 14 années (1991 à 2004) pour 3 sous-bassins pour lesquels la Région Wallonne ne disposait pas de données horaires suffisantes : • La Warchenne à Malmédy (+/- 29 km²), • La Wamme à Hargimont (+/- 81 km²), • La Gueule à Sippenaeken (+/- 120 km²). [less ▲]

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See detailCarte hydrogéologique de Alleur - Liège 42/1-2, 1/25.000 : [notice explicative]
Ruthy, Ingrid ULg; Dassargues, Alain ULg

Book published by Ministère de la Région wallonne, DGRNE - Première édition: 2002 - Actualisation partielle : mai 2006 (2006)

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See detailCaractérisation des nappes aquifères: une nécessité pour leur protection et leur gestion
Dassargues, Alain ULg

Scientific conference (2006, February 23)

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See detailDescription of hydrogeological conditions in the Geer sub-catchment and synthesis of available data for groundwater modelling
Orban, Philippe ULg; Batlle-Aguilar, Jordi; Goderniaux, Pascal ULg et al

Report (2006)

In the framework of Workpackage R3 Meuse, the Hydrogeology Group of the University of Liège (HGULg) will develop a groundwater flow and transport model for the Geer sub-catchment (tributary of the Meuse ... [more ▼]

In the framework of Workpackage R3 Meuse, the Hydrogeology Group of the University of Liège (HGULg) will develop a groundwater flow and transport model for the Geer sub-catchment (tributary of the Meuse). This model will be used for collaborations HYDRO H1 and TREND T2. The deliverable describes the hydrogeological conditions prevailing in the sub-catchment and provides a synthesis of available data for groundwater and transport modelling. [less ▲]

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See detailGeo-electrical data fusion by stochastic co-conditioning simulations for delineating groundwater protection zones
Dassargues, Alain ULg

in CMWR XVI - Computational Methods in Water Resources (2006)

In hydrogeology, advances in the delimitation of protection zones are made by the use of stochastic simulations integrating all available data. In practice, due to the few available measurements of the ... [more ▼]

In hydrogeology, advances in the delimitation of protection zones are made by the use of stochastic simulations integrating all available data. In practice, due to the few available measurements of the main parameters (hard data), it is very useful to integrate several secondary properties of the media as indirect data (soft data) to reduce the uncertainty of the results. In aquifers, most of the solute spreading is governed by the hydraulic conductivity (K) spatial variability, which is generally considered as the main uncertain parameter. A stochastic approach integrating hydraulic conductivity measurements (hard data), head observations and shallow electrical resistivity tomography (soft data) is presented. Results are discussed on a synthetic and on a practical case. It is shown in practice how the uncertainty of the well capture zone probability distribution (CaPD) can be reduced. Since geophysical data and head observations are easier to collect on the field then hydraulic conductivity measurements, they are generally more abundant. The methodology presented can even be used in real applications when little or no information is available about the hydraulic properties, through the conditioning on geophysical data and/or head observations. [less ▲]

Detailed reference viewed: 189 (12 ULg)