Contribution of geophysical surveys to groundwater modelling of a porous aquifer in semiarid Niger: An overview |
| |
| Authors: | Marie Boucher Guillaume Favreau Marc Descloitres Jean-Michel Vouillamoz Sylvain Massuel Yahaya Nazoumou Bernard Cappelaere Anatoli Legchenko |
| |
| Institution: | 1. IRD, HSM, 276, avenue de Maradi, BP 11416, Niamey, Niger;2. IRD, HSM, université Montpellier-2, place E.-Bataillon, CC MSE, 34095 Montpellier cedex 5, France;3. Département de géologie, université Abdou-Moumouni, BP 10662, Niamey, Niger;4. IRD, LTHE, BP 53, 38041 Grenoble cedex 9, France;5. IRD, LTHE, Indo-French Cell for Water Science, Indian Institute of Science, 560012 Bangalore, India;6. CSIRO Land and Water, Private Bag 5, Wembley 6913, Australia |
| |
| Abstract: | Subsurface geophysical surveys were carried out using a large range of methods in an unconfined sandstone aquifer in semiarid south-western Niger for improving both the conceptual model of water flow through the unsaturated zone and the parameterization of numerical a groundwater model of the aquifer. Methods included: electromagnetic mapping, electrical resistivity tomography (ERT), resistivity logging, time domain electromagnetic sounding (TDEM), and magnetic resonance sounding (MRS). Analyses of electrical conductivities, complemented by geochemical measurements, allowed us to identify preferential pathways for infiltration and drainage beneath gullies and alluvial fans. The mean water content estimated by MRS (13%) was used for computing the regional groundwater recharge from long-term change in the water table. The ranges in permeability and water content obtained with MRS allowed a reduction of the degree of freedom of aquifer parameters used in groundwater modelling. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
