Forward and Inverse Resistivity Modelling on Complex Three Dimensional Structures Using the Finite Element Method

Abstract

Dispositif électrique choisi pour la prospection de surface___________________ VI.1.2 Simulation des données et paramètres d'inversion _________________________ VI.1.3 Hétérogénéité conductrice ____________________________________________ VI.2.1 Hétérogénéité résistante _____________________________________________ Résumé : Données collectées en surface _______________________________________ VI.2 DONNEES COLLECTEES SUR DES STRUCTURES DE GEOMETRIE COMPLEXE ________________________________________________________________ VI.2.1 Le modèle ________________________________________________________ VI.2.2 Dispositif électrique choisi ___________________________________________ VI.2.3 Utilisation de différentes valeurs du pas d'ajustement des paramètres __________ VI.2.4 Effet du modèle de départ ____________________________________________ VI.2.5 Effet du bruit de mesure ________________________________________________ VI.2.6 Utilisation d'un modèle de référence ___________________________________ VI.2.7 Calcul de la région d'investigation (ROI) ___________________________________ Résumé : Données collectées sur des structures de géométrie complexe ______________ CHAPITRE VII CONCLUSIONS ET PERSPECTIVES _________________________ VII.1 APPORTS DU TRAVAIL ____________________________________________ VII.1.1 Utilisation de CESAR-LCPC pour la modélisation électrique ________________ VII.1.2 Modélisation directe ________________________________________________ VII.1.3 Modélisation inverse ________________________________________________ VII.2 PERSPECTIVES ___________________________________________________ BIBLIOGRAPHIE _______________________________________ ANNEXE TECHNIQUE ___________________________________ Les éléments de CESAR-LCPC pour un problème de diffusion ______________________ Particularités du progiciel CESAR-LCPC ________________________________________ Particularité du solveur _______________________________________________________ Conditions aux limites _______________________________________________________ Stockage de la matrice globale _________________________________________________ Allocation pseudo-dynamique des tables _________________________________________

Preliminary hydrogeophysical investigation at the 10th of Ramadan City, Egypt, by 1D and 2D inversion of VES data

“…The 1D resistivity sounding method might not be sufficiently accurate for such situations. With the advent of the powerful measuring systems and the high computing power, new 2D and 3D surveys and inversion codes have been developed (e.g., Loke and Barker ; Günther ; Marescot et al ). Moreover, some authors have devoted their research work to the 2D and 3D inversion of Schlumberger sounding data (Tripp et al ; Tong and Yang ; Uchida ; Santos and Sultan ).…”

“…The electrical resistivity method has been extensively used for mapping groundwater aquifers (Chistensen and Sørensen ) and the investigation for aquifer vulnerability (Sørensen et al ). Vulnerability of an aquifer is closely related to the heterogeneity of the clayey layers above it, and the clay content defines its electrical resistivity, where clayey, low‐permeable formations tend to show low resistivities, whereas sandy, permeable formations tend to show high resistivities.…”

“…Vulnerability of an aquifer is closely related to the heterogeneity of the clayey layers above it, and the clay content defines its electrical resistivity, where clayey, low‐permeable formations tend to show low resistivities, whereas sandy, permeable formations tend to show high resistivities. The electrical resistivity method is competent for mapping both low‐and high‐resistive formations and therefore is a valuable tool for vulnerability studies (Chistensen and Sørensen ; Sørensen et al ; Goyal ; Aweto and Mamah ).…”

2D and 3D resistivity inversion of Schlumberger vertical electrical soundings in Wadi El Natrun, Egypt: A case study

“…The increase in computing power led to developing new 2D and 3D inversion codes (Günther, 2004;Loke and Barker, 1996;Marescot, et al, 2005;Santos and Sultan, 2008). However, there are a few references specifically devoted to 2D and 3D inversion of 1D Schlumberger soundings (Santos and Sultan, 2008;Uchida, 1991).…”

Geophysical evidence for the hydro‐tectonic origin of the Sabkha El Sheikh Zwayed Lake and the shallow fresh water supplies, Northern Sinai, Egypt

“…, Günther , Marescot et al . ), and there are a few works specifically devoted to 2D inversion of a resistivity data measured in 1D (Uchida , Santos et al . ).…”