Geoelectric and mineralogical studies for foundation soil characterization in new Luxor city, Upper Egypt

The new Luxor city was proposed by the Egyptian government as a new constructional and building site in order to face the increasing population density around the two banks of the river Nile. It is important prior construction of buildings to characterize the foundation soil. So, vertical electrical resistivity survey and mineralogical investigation were conducted for this purpose. The results obtained from the interpretation of the sounding data indicate that the lithological succession of the study area consists of four geoelectric layers. The top layer corresponds to the surface loose sediments of conglomerate, gravel, and sand. The second geoelectric layer is composed of sand and gravel. The third layer is composed of silty clay, sandy clay, and clayey sand. The fourth geoelectric layer is composed of dry sandstone. The X-ray diffraction (XRD) results of samples collected from the clay-rich layer revealed the presence of smectite mineral as predominate clay minerals which is characterized by its swell potentiality on wetting. Accordingly, the clay zone recorded within the third layer must be taken into consideration during designing the foundations at new Luxor city especially this layer was located at shallow depth range between 1.6 and 7.5 m and attains a relatively big thickness that reach up to 33.5 m in some parts. This study emphasizes the importance of the integration of geophysical investigation and mineralogical analysis of the foundation soil for optimal characterization of a site.