Abstract
In the basement of southwestern Niger, weathering and fractured zones concentrate most of the groundwater. This study focuses on fractured media and aims to identify areas of productivity in this aquifer to improve the region’s water coverage. The cartographic approach developed made it possible to establish synthetic maps based on multi-criteria analysis. The hydrogeological parameters selected include fracturing data, drainage system, slope and piezometric level as well as shallow and deep lithology. The choice of these criteria is based on their physical meaning but also on the availability of data. The integration of all the criteria in a GIS allowed to generate maps of recharge and potential productivity of fractured aquifers in the area. The validation of these thematic maps with independent data confirms their utility as reference standards for accessibility for future resource exploitation. Like any spatialization tool, potential recharge maps will provide valuable information about areas where infiltration is more important, and help control and manage risk zoning. The upward evacuation effect is even more prominent along the lineaments, faults or fractures: thus, to avoid possible pollution and to locate the future hydraulic structures, the analysis of the potential recharge zones remains necessary. The potential productivity index map, in addition to the very punctual sites identified by the fracturing study, made it possible to define areas of high potential productivity.
Highlights
Basement hydrosystems generally correspond to anisotropic discontinuous media with high permeability contrasts [1]
This study focuses on fractured media and aims to identify areas of productivity in this aquifer to improve the region’s water coverage
We show that multi-criteria analysis can be used to map the groundwater potential zones in fractured aquifer system
Summary
Basement hydrosystems generally correspond to anisotropic discontinuous media with high permeability contrasts [1]. Even under arid basement conditions, where the likelihood of successful drilling is low, geospatial techniques have been suggested as an essential part of the further processing of the combined field data, and even more a powerful tool for groundwater resource mapping, prospecting, planning and management [8] [9] [10]. Throughout the southwestern Niger, the failure rate of drilling (i.e. a flow lower than 0.5 m3 per hour) is still around 40% [17] Despite this limitation, the fissured basement aquifers in Liptako are in great demand to meet the growing water needs of the population. Our view is that detailed studies and a multidisciplinary approach will improve our knowledge of the fractured basement environments and open new prospects on the optimization of the drilling failure rate reduction. The map of potential recharge areas helps to generate a potential productivity index map of underground aquifers, as well as to optimize the use of available data
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
