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The present study aims to investigate the ground water accumulations present in the area located west of the Gulf of Suez, to face the new urbanization settlements of industrial national projects in the study area using geoelectrical and magnetic measurements. Magnetic data interpretation was carried out using the RTP magnetic data (or, through analyzing the RTP aeromagnetic map) to determine the depth to the surface of basement rocks and delineate the trends of structural elements. The results of magnetic interpretation indicated that the depth to the basement surface is ranging from 1200 to 3500 m and the trends of encountered structural elements are mainly NE-SW, NW-SE, NNW-SSE and E-W directions. Seventeen vertical electrical soundings of Schlumberger configuration were measured with AB/2 ranging from 1.5 m to 1500 m at the southern part of the study area. The results of quantitative interpretation of geoelectrical data indicated that the subsurface section consists of six different geoelectrical units; the first unit represents the Quaternary gravel and sand of high resistivity values and thickness of about a few meters. The second geoelectrical unit exhibits moderate resistivity values ranging from 23 to 100 ohm m and thickness ranging from 4.5 to 67 m which represents the fresh water aquifer in the study area, while the lithology of this layer consists of sandstone and limestone which belongs to the Upper Miocene. The third geoelectrical unit is composed of sandy clay and limestone which belongs to the Middle Miocene deposits and shows low resistivity values ranging from 6 to 7 ohm m and thickness ranging from 44.5 m to 66 m. This third layer represents the second aquifer (brackish water). The fourth geoelectrical unit consists of limestone and clayey limestone which belongs to the Lower Miocene deposits and exhibits moderate resistivity values ranging from 16 to 33 ohm m, while the thickness of this unit ranges from 47-102 m. This layer represents the third aquifer (brackish water). The fifth geoelectrical unit reveals very low resistivity values of about 2-5 ohm m and

Geophysical tools such as magnetic, gravity and electric resistivity have been used to delineate subsurface structures, groundwater aquifer around Cairo-Belbies Desert road. A dipole-dipole section was measured at the central part of the study area with 2100 m length and electrode spacing 50 m for greater penetration depth. The results of the inverse resistivity data indicate that the study area includes two groundwater aquifers at different depths. The shallow aquifer water is near the surface and the deep aquifer lies at depth of about 115 m and exhibits low resistivity values ranging from 20 to 100 ohm m. One hundred and fifty-two gravity stations were measured using Autograv gravimeter (CG3), different gravity corrections (drift, elevation and latitude corrections) were applied. The corrected data represented by Bouguer anomaly map were filtered into regional and residual gravity anomaly maps. The residual gravity map indicates that the area is dissected by many faults with NW-SE, N-S, E-W and NE-SW trends. One hundred and fifty-three ground magnetic measurements are collected using two Proton magnetometers (Envimag). The corrected magnetic data are represented by total magnetic intensity map that was reduced to the magnetic pole. 3D magnetic modeling was applied to detect the depth

The new urban development is an important priority in Egypt to face a rapid increase in the population during the last few decades. As a case study, the geotechnical assessment of the New Minia City is studied applying direct current (DC) resistivity technique. In the presented study, the DC resistivity data are interpreted to (i) characterize the subsurface layer distributions, (ii) deduce the subsurface structures considering the surface geological and structural setting and borehole information and (iii) predict geotechnical parameters of the bedrock based on empirical relationships. The inversion results of DC resistivity data indicate that a lens of clay is locally capping the fractured limestone in different parts of the area. The constructed geoelectrical cross-sections show that the limestone bedrock is highly fractured regarding many normal faults trending in the NW and NE directions. In an attempt to derive empirical relationships for predicting the geotechnical parameters, the inverted resistivity values of the fractured limestone were correlated with different geotechnical parameters, Rock Quality Designation (RQD) and Unconfined Compressive Strength (UCS). It is noticed that there are good correlations between the limestone resistivity values and geotechnical parameters obtained from borehole data applying linear relations. Accordingly, the results indicate that the DC resistivity method constitutes a valuable technique to introduce a preliminary geotechnical assessment for new urban areas.

The lowermost portion of the sedimentary section in Gulf of Suez basin is mostly of low resolution and hardly interpret. This may be attributed to the bad seismic reflection that stops at a certain limit and fails to reach the deep settings, or due to non-coverage of boreholes. Herein, the gravity data was reinterpreted utilizing the stripping technique as an alternative tool to overcome the seismic failure. The process simply consists in calculating the gravity effects of the shallow rock-units and removing them from the Bouguer map, then in analyzing the remaining gravity. The ordinary seismic analysis was performed to control the geometry of the Miocene-Post Miocene formations, and density was driven from boreholes. Further analyses were done on the stripped map to obtain details about the deep sources. Generally, the study suggests a complex structure at Pre-Miocene level more than that of Miocene. It delineates two main troughs; Miocene basin to the east and Pre-Miocene basin (involves three sub-basins) to the west, separated by a structural ridge, all are northwesterly oriented. The basement is very disturbed by cross-faults, with no evidence support presence of igneous intrusions along. Two different forces (NW-SE compression and NE-SW tension) affected the region.

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The groundwater resources in the Nile Delta region are an important resource for freshwater because of rising water demand due to anthropogenic activities. The goal of this study is to quantify groundwater sensitivity to pollution in the Nile Delta by a modified GIS-based DRASTIC-LU model. In this study, we utilized two types of modified DRASTIC-LU models, generic and pesticide, to determine the groundwater vulnerability rates to contamination. The results of the generic DRASTIC-LU model showed that the research region, except for the northwestern part with moderate vulnerability of 3.38%, is highly and very highly vulnerable to pollution with 42.69 and 53.91%, respectively. Results from the pesticide DRASTIC-LU model, on the other hand, also confirmed that, except for the northwestern and southern parts with a moderate vulnerability of 9.78%, most the Nile Delta is highly and very highly vulnerable with 50.68 and 39.53%, respectively. A validation of the model generated was conducted based on nitrate concentrations in the groundwater and a sensitivity analysis. Based on the nitrate analysis, the final output map showed a strong association with the pesticide vulnerability model. Examining the model sensitivity revealed that the influence of depth to water and net recharge were the most important factors to consider.