Variations in conductivity in the near-surface, such as the presence of small and localized threedimensional (3D) bodies, cause a galvanic distortion in direct current (DC), so the measured apparent resistivity is affected by a constant shift on a log scale called Static Shift. In this study, We used electromagnetic sounding techniques to correct for the static shift affecting the electric resistivity data only. The term "static shift" is used because apparent resistivity is distorted by a constant, shifting value (S) on a log scale, which lead to misleading interpretation. It was noticed that the two data sets' sounding curves at the same location have a concordant pattern. The problem was noticed in the 1D inversion models for VES and TEM were not matched together before removal of VES data shift. The TEM and VES measurements are represented on the same graph, then the shifting factor (S) is calculated for the VES curves to directly overlap the TEM curve. The 1D inversion model for VES curves after removing the shifting factor shows matched data with the TEM 1D model.

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Wadi Queih and Wadi Safaga lie in the central part of the Eastern Desert of Egypt. The airborne gamma-ray spectrometric data of the study area have been interpreted qualitatively and quantitatively and correlated with the surface lithologic units to define the anomalous uranium zones and to reveal if any association is present between the radiometric anomalies and the structural trends.The radiometric data have been treated statistically. The results revealed that the area has a wide range of radioactivity ranging from 0.1 to 23.6 Ur for the total-count (TC), 0.1 to 3.3 % for potassium (K), 0.01 to 19.1 ppm for equivalent uranium (eU), and 0.29 to 18.9 ppm for equivalent thorium (eTh). The calculated CV values for all the rock units in the study area are less than 100% for three radio-elements (K, eU, eTh), except for potassium in Thebes Formation. The younger granites and Duwi Formation have the highest radiometric values. The lowest values exist over ophiolitic metagabbro, basic metavolcanics, metasediments, serpentinites, and Umm Gheig Formation. The generated composite radioelements and composite image maps define the locations of the high anomalous radiometric and eU zones as bright white areas. The most radioactive anomalies have NW-SE and NE-SW trends. ARTICLE HISTORY

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Advanced technology in processing the old seismic data in the Gulf of Suez (G.O.S) has been used and applied using new parameters to emphasise the optimisation of geological structures and stratigraphic units as much as possible. The primary reflections in Gulf of Suez have low frequency while multiple reflections have higher frequency where there is a high reflection contrast in the shallow section represented by Zeit Formation due to alternation of shale and anhydrite that generates a lot of multiple reflections. The deeper formations will be affected by low-frequency reflections resulted from the incident energy itself with the common attenuation parameters such as transmission loss, adsorption, and spherical spreading of waves. Otherwise, the data in the Gulf of Suez suffer from a lot of loss mechanism from the salt of South Gharib Formation and anhydrite of Zeit Formation. In this study, new software are adapted to apply new technology in processing and analysis of seismic data such as VISTA 11 software from GEDCO company. After a lot of iterations of all seismic data parameters, seismic flows and parameters have been chosen to retain the primary frequency contents and relative amplitude while suppressing multiples energy. The reprocessing produced seismic sections with the increased temporal and spatial seismic resolution, facilitating more accurate interpretation of the data. Enhanced imaging of both the salt structures and the subsalt sequence has been achieved, which in turn leads to a more and better understanding of salt deformation and improve the mapping of structural subdivisions within the study area.