Surface and subsurface structural mapping using low frequency radar: A synthesis of the Mauritanian and Egyptian experiments
Résumé
Space-borne remote sensing imaging allows precise coverage of vast regions with basic data for geological exploration while signif- icantly reducing exploration costs. These data provide valuable information for geological mapping and mineral exploration through highlighting geological structures such as lineaments, faults, and lithological contacts. The use of radar constitutes a very useful com- plement to optical remote sensing data, especially as regards to the surface but also the subsurface detection of structures. Specifically in arid desert areas, radar waves penetrate the dry surface sand sheet and highlight concealed geological structures or fossil river systems. We present a synthesis of two experiments designed to compare the contribution of radar and optical images to geological exploration using the Akjoujt region in Mauritania and the Bir Safsaf region in Egypt as study sites. Ground-Penetrating Radar (GPR) is used to evaluate volume scattering coming from subsurface dielectric heterogeneities in cases of radar penetration of the dry sand. This evalu- ation is based on correlating the reflectivity of the GPR section with backscattering coe