Contribution of Electrical Resistivity Tomography (ERT) and Vertical Electrical Sounding (VES) to delineate the structural organization of the Palaeozoic Zone in the Rabat-Tiflet region (Morocco)

Abstract

In this geophysical study, we carried out four Electrical Resistivity Tomography (ERT) profiles and one Vertical Electrical Sounding (VES) in the Palaeozoic Zone in the Rabat-Tiflet region, Morocco. Measurements were accomplished in and around the limestone quarry exploited by the company named ‘Société Des Granulats de Tiflet’ (SDGT) located in our study area. The aim of this study is to delineate the structural organization, especially the spatial distribution of limestone deposits which represents the main formations of this Palaeozoic zone in the Rabat-Tiflet region. Analysis of 2D inverse model resistivity sections show some anomalous contacts and the existence of subsurface lenticular bodies with resistivity going from 100 to 1500 Ωm, potentially corresponding to limestone rock. Also, vertical electrical sounding achieving near the SDGT showed a layer with a resistivity of 317 Ωm at 6 m depth interpreted as limestone conglomerates or limestone deposits. More, during our geological survey, we observed along the Oued Bou Regreg valley and in some abandoned quarries located in the same area, lenticular blocks with different sizes globally having an NNW–SSE direction. These results contributed, even in small scall, to clarify the structural organization of the Palaeozoic Zone in the Rabat-Tiflet region. To map out with high precision this geological complex region, more electrical and seismic profiles as well geochemical studies are recommended.