Two geophysical methods were used for mapping the archaeological features at Qantir village: magnetic and resistivity surveys. The magnetic survey was carried out before the resistivity survey in order to evaluate the distribution of hidden archaeological features and cultural relics. It was conducted over an area of 120 ð 100 m using a fluxgate gradiometer (Geoscan FM36) that measures the vertical gradient of the geomagnetic field. The readings were logged every 0.5 m along 20 m, zigzag traverses. The resultant data were processed and treated to produce a high-quality magnetic image. The final magnetogram and graphical interpretation plot show the distribution of high and low magnetic features that reflect the buried archaeological and nonarchaeological features. Subsequently, a resistivity survey was carried out over interesting areas identified from the initial results of the magnetogram. Four Wenner profiles were also measured, named P1W, P2W, P3W and P4W. The minimum electrode spacing used through all the profiles was 1 m and the maximum electrode spacing varied from one profile to another according to its length. These data were used to construct four apparent resistivity pseudosections. A comparison between the magnetic vertical gradient profile and resistivity inverse models was performed in order to check the value of using the Wenner configuration in parallel with the gradiometer survey. The geophysical investigation mapped some archaeological features with a high probability of indicating the presence of storage and burial chambers, bisecting walls, ditches and streets.

Saltwater intrusions into shallow aquifers near the coast are an important environmental problem along the whole coastal strip of the western desert of Egypt. This phenomenon was studied in two selected coastal depressions on the eastern side of the Matruh area by a geoelectrical survey which comprised several 1D sounding points as well as 2D and 3D resistivity‐imaging surveys. For the 2D and 3D field surveys, pole‐dipole (both forward and reverse) and pole‐pole arrays were used, respectively. The spacing between adjacent electrodes was 10 m for the 2D resistivity surveys. A 5 × 5 grid of electrodes was used for the 3D survey. The spacing between electrodes was 10 or 20 m, depending on the expected depth of freshwater in each respective area. The choice of electrode spacing was based on the results of interpretation of the depth of the freshwater–saltwater boundaries, as derived from 1D resistivity soundings using a Schlumberger array. The sounding points were distributed over the study areas and the soundings were conducted prior to the 2D and 3D survey. The data sets were inverted using the smoothness‐constrained least‐squares method. The inversion results indicate that the subsurface resistivity distributions in the whole area are highly inhomogeneous and change rapidly within a short distance. However, from the resulting models, it was possible to correlate the ranges of resistivity with subsurface geological information available from shallow boreholes. The horizontal and vertical sections presented illustrate the configuration of the subsurface conditions that would have been, most probably, insufficiently accurate in the case of 1D modelling.

Geophysical techniques, such as magnetic and geoelectric ones, are useful for ore deposit exploration, represented by titanomagnetite. Titanomagnetite is a mineral composed of oxides of titanium and iron. Forty-seven magnetic profiles have been measured using two proton magnetometers to cover the study area with a direction perpendicular to the ore outcrops. The qualitative interpretation of magnetic data indicates elongated highly magnetized anomalies extending northeast to southwest. The quantitative interpretation of magnetic data was carried out using 2D magnetic inversion. The results of the magnetic interpretation indicated ore deposits at < 10 m depth in the area with highly magnetic anomalies, and the magnetic anomalies related to the titanomagnetite ore bodies have a tabular form with thickness ranging from 7 to 100 m. Seven vertical electrical soundings were carried out along selected sites according to the geologic map and field observation for the geologic features of the ore bodies in the study area. The results of resistivity inversions indicated that there are many conductive bodies, which have resistivity values < 100 Ω m. Three electric resistivity tomography lines are made trending east-west perpendicular to the direction of exposed ore in the area. The profiles were processed using the finite element algorithm available in the Res2dinv program, and the generated models delineate the shape and orientation of the supposed ore.

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