Application of Electrical Methods for the Recognition of the Geometry of the Senonian Aquifer in the West Boudnib (Errachidia-Morocco)

Abstract

The province of Errachidia-Boudnib, located in southeast Morocco, is an arid area known for its rarity of precipitation. Desertification and overexploitation of groundwater have accentuated the downward trend in groundwater levels in aquifers. This study is made for implementation in parallel with the exploitation programs, of comprehensive studies for the recognition of the aquifer of Sénonien. Geophysical methods (drilling and electrical tomography), allow the geometric configuration of the aquifer system of the region of Boudenib, to help those responsible to make good decisions on the positions of the drilling of reconnaissance or exploitation. For these, two geophysical methods were used in this study, electrical boreholes (large extent) and electrical tomography (small extent). The first method allowed us to specify the appearance of the roof of the resistant substratum R2 corresponding to the limestone-clay sandstone formations of the base of the Sénonien whose depth is between 440 and 580 m admitted aquifer; The second method based on the study of the profile by electrical tomography (BD1) profile revealed the presence of conductive lenses corresponding to an aquifer. Therefore, the Senonian aquifer formation corresponds to sands, sandstone, and sandy clays.