Journal of the Association of Arab Universities for Basic and Applied Sciences, Apr 1, 2013
The flood plain of the Nile River has been a safe dwelling throughout history. Recently with a gr... more The flood plain of the Nile River has been a safe dwelling throughout history. Recently with a growing population and vast growing urbanization some buildings have started to experience structural damages, which are not related to their construction design, but rather to the ground conditions around the buildings' foundations. Variations in properties of the soil supporting the buildings' foundations such as soil bearing capacity, moisture content and scouring may eventually lead to the failure of these buildings. This study is attempting to characterize the variations in the soil properties around the City Star shopping mall, in eastern Cairo, where a large building has tilted over the past few years. This tilting may lead to the collapse of the whole building if it continues at the same rate. An integrated geophysical investigation including multi-channel analysis of surface wave (MASW), ground penetrating radar (GPR) and 2-D electrical resistivity tomography (ERT) was used around the affected building to help detect possible causes of deterioration. The GPR data showed a soil-fill layer overlaying a thick bottom layer of higher moisture content. The MASW data revealed a middle layer of relatively low shear wave velocity sandwiched between two relatively high shear wave velocity layers. The ERT data showed an upper low resistivity layer overlying a high resistivity layer. Integrating the interpretations of the three geophysical methods provide a combined model that reflects lateral and vertical variation in the soil properties. This variation becomes dramatic near the tilted corner of the building.
Abstract The integration of geophysical data with direct hydrogeological measurements can provide... more Abstract The integration of geophysical data with direct hydrogeological measurements can provide a minimally invasive approach to characterize the subsurface at a variety of resolutions and over many spatial scales. The field of hydrogeophysics has attracted much attention during the ...
This study integrates remote sensing and geophysical data to identify the hydrological conditions... more This study integrates remote sensing and geophysical data to identify the hydrological conditions of the Naqab reservoir watershed. The main objectives of this study are identification and the interpretation of subsurface structures and their impact on groundwater flow, the relationships between structures and groundwater and the optimum way for watershed management in this subbasin. Geophysical data including, ground magnetic survey and 1D electrical resistivity sounding helped in identifying the lithology and delineating zones of groundwater occurrence. The magnetic data delineated the basement rock, aided in characterizing the geometry of the subsurface structures that control the land surface features and constrain groundwater flow system. The interpreted subsurface structure elements include six sets of faults trending NE-SW, NW-SE, NWW-SEE, NEE-SWW, N-S and E-W. The basement depth was estimated at zero at the southern part and about 5187 m at the northern part. Two aquifer systems were characterized, the shallow aquifer of the Wata Formation (Upper Cretaceous) and the deep aquifer of the Malha Formation (Lower Cretaceous). The probability of groundwater occurrence increases towards the central part of the study area to north direction, where the thickness of the sedimentary basin reaches its maximum at the center of the study area. Different trends of faults were interpreted from the geoelectrical cross-sections along two transects. Three patterns of faults were characterized including step faults, graben faults and horst faults. These faults could be indicated on the geo-electrical section by a marked difference in the layers` thicknesses. The magnetic data confirmed the locations of the faults delineated by the electrical resistivity profiles. The outlined faults are trending mainly in NE-SW, NW-SE, NWW-SEE, NEE-SWW and E-W directions. Lineament structures delineation and drainage pattern analysis were evaluated and interpreted from the analysis of remote sensing (RS) data and geographic information system (GIS) technique. The SRTM-DEM (Shuttle Radar Topographic Mission-Digital Elevation Model) was also utilized to automatically identify and extract drainage network. Interpretation and analysis of the inferred lineament structures indicate the presence of a number of main lineament populations that trends: NE-SW, NW-SE, NNW-SSE, NWW-SEE, E-W and N-S. Meanwhile, the interpretation and analysis of drainage pattern network indicate the presence of three main lineament structures that trends: NW-SE, NE-SW and NWW-SEE. Azimuth distribution analysis of both the measured structures and drainage channels shows similar trends, except for very few differences in the prevailing trends. Similarity in orientation of lineament structures, drainage system, and subsurface structural trends were recognized in the area under study. In conclusion, the integration between remote sensing and geophysical data revealed a close matching between the surface structural lineaments and subsurface structural trends could be verified. The preferred conduits of surface runoff and groundwater flow, as well as, the proper locations for groundwater exploitation could be determined.
Electrical resistivity survey in the form of vertical electrical sounding was conducted at the 10... more Electrical resistivity survey in the form of vertical electrical sounding was conducted at the 10th of Ramadan City, Egypt, to analyse subsurface lithology distribution and the interrelation between the possible infiltrated wastewater from oxidation ponds and the surface seepage emerged at the city centre. Special interest was paid for tracing the low-resistivity clayey layer, which can act as a barrier against surface water percolation and as a low permeable zone to form local perched water system. Vertical electrical sounding data by Schlumberger electrode configuration were taken at 17 stations along a line extended from the city centre to the oxidation ponds used for wastewater treatment. The data were inverted by using 1D and 2D inversion schemes to construct geoelectrical cross section along the surveyed line. The geoelectrical layers were interpreted principally in terms of lithology and water content by correlation with borehole information. From the obtained results, four layers were identified in the subsurface medium. The upper three layers are located above the regional water table, whereas the fourth one was interpreted to be fully water saturated. The second layer from the surface is of great importance as it is the low-resistivity clayey layer. This layer is discontinuous along the survey line. Downward infiltration of wastewater from the oxidation ponds is possible especially at the pond No. 2 as the clayey layer was interpreted not to exist at the site. The infiltrated wastewater from the oxidation ponds was interpreted not to be the cause of the surface seepage emerged at the city centre because the clayey layer dips toward opposite direction. The probable sources of the seepage were considered the local surface infiltration from excess irrigation water in the nearby cultivated land and/or leakage from the underground water utilities in the city centre. the environment (EMG 1997). The cumulative impact of industrial discharges to the ambient environment can pollute water that is used for drinking and air that is breathed by workers and residents of these cities. The 10th of Ramadan City, the present case study, is the oldest and largest industrial city in Egypt. It was constructed at the eastern fringe of the Nile Delta region, along the Cairo-Ismailia desert road, between latitudes 30° 15` and 30° 25` N and longitudes 31° 37` and 31° 52 E (Fig. 1). The city is located in lack of surface water resources; therefore, it depends on groundwater as a main source for water supplies needed for drinking and agricultural and industrial activities. A Quaternary aquifer is the main groundwater reservoir in this area. It is composed of graded sand and gravel with clay intercalations. The industrial activities in the city release various solid, liquid, and gaseous wastes. Moreover, the city has attracted a
This study integrates remote sensing and geophysical data to identify the hydrological conditions... more This study integrates remote sensing and geophysical data to identify the hydrological conditions of the Naqab reservoir watershed. The main objectives of this study are identification and the interpretation of subsurface structures and their impact on groundwater flow, the relationships between structures and groundwater and the optimum way for watershed management in this sub-basin. Geophysical data including, ground magnetic survey and 1D electrical resistivity sounding helped in identifying the lithology and delineating zones of groundwater occurrence. The magnetic data delineated the basement rock, aided in characterizing the geometry of the subsurface structures that control the land surface features and constrain groundwater flow system. The interpreted subsurface structure elements include six sets of faults trending NE-SW, NW-SE, NWW-SEE, NEE-SWW, N-S and E-W. The basement depth was estimated at zero at the southern part and about 5187 m at the northern part. Two aquifer sy...
East Cairo is characterized by abundant quarries that have been used as landfill sites for solid ... more East Cairo is characterized by abundant quarries that have been used as landfill sites for solid waste. These sites have become part of the urban sprawl of New Cairo, and their detection became difficult from the ground surface. In this study, analysis of multi-temporal high-resolution satellite images and electrical resistivity tomography (ERT) data were used to detect and delineate a buried landfill site located near the Ring Road, East Cairo, Egypt. Analysis of changes detected on the satellite images revealed that the study site was a WNW-oriented Quarry until 2005 and then randomly filled with heterogeneous solid materials. ERT survey was planned based on the result of change detection. On the plan view, the ERT measurements have outlined the electrically conductive zones which are occupied by filling material and distinguished them from the resistive zones that symbolize the natural soil areas. By assimilation of the satellite images and the ERT results, two distinguished geoe...
Transient ElectroMagnetic (TEM) sounding and Ground ElectroMagnetic (GEM) profiling have been con... more Transient ElectroMagnetic (TEM) sounding and Ground ElectroMagnetic (GEM) profiling have been conducted at Hawara archeological area, El Fayoum, Egypt to investigate the subsurface water and its effect on the archeological targets at this area. This archeological site comprises Hawara pyramid, the northern necropolis and a southern mortuary complex called “labyrinth”. Nowadays Hawara area is entirely abandoned and surrounded by cultivated areas, as well as, a surface water canal named “Bahr Wahba”. The surface and underground water bodies have negative effects on the foundation of Hawara pyramid and the labyrinth site, where the entrance of the pyramid is today flooded to a depth of about 6 meters below the ground surface. TEM data have been acquired at three sites in this area comprising the cultivated land, the pyramid and the labyrinth, while the GEM survey was conducted inside the labyrinth site. Integrated interpretation of these data sets indicates that, the agricultural activ...
The mines of magnetite and hematite occupy some areas of the Eastern Desert at Wadi Abu Subeira, ... more The mines of magnetite and hematite occupy some areas of the Eastern Desert at Wadi Abu Subeira, northeast of Aswan city which is a volcanic and tectonic area. It is one of the largest arc sedimentary rock sequence affected by faulting and folding due to repeated stages of deformation. The iron deposits in this area are of oolitic type and exist in two bands inter-bedded with ferruginous sandstone and clay layers. The thickness of the bands varies from 0.5 to 3.5 m. Detailed geophysical work has been carried out on the promise site of Abu Subeira to identify the lateral and vertical distribution of the iron-ore deposits at this area. Many geophysical methods were applied in this study including Land Magnetic Survey, Electrical Resistivity Imaging (ERI), Induced Polarization (IP), and Time-Domain Electromagnetic (TDEM). Besides, rock samples from the iron ores were collected for chemical analysis. The X-ray fluorescence (XRF) and X-ray diffraction (XRD) techniques were applied for estimation of iron concentration (Fe %) and other minerals’ contents in the rock samples. The field data sets were measured along the iron ore bodies of Wadi Abu Subeira and were processed and analyzed by the proper software packages. The areas with iron ore deposits were expressed in the geophysical results by low resistivity, high chargeability, and moderate to high magnetic anomalies. Integrated interpretation of the obtained results revealed that the ore deposits exist in the form of lenses with variable thickness ranging from few meters to about 30-m thick. The mineral occurrences in Abu Subeira are managed by the major faults and the hydrothermal fluids flowing along these faults.
Vertical Electrical Sounding (VES) and Transient ElectroMagnetic (TEM) survey have been applied f... more Vertical Electrical Sounding (VES) and Transient ElectroMagnetic (TEM) survey have been applied for characterizing the groundwater aquifers at El Sadat industrial area. El-Sadat city is one of the most important industrial cities in Egypt. It has been constructed more than three decades ago at about 80 km northwest of Cairo along the Cairo-Alexandria desert road. Groundwater is the main source of water supplies required for domestic, municipal and industrial activities in this area due to the lack of surface water sources. So, it is important to maintain this vital resource in order to sustain the development plans of this city. In this study, VES and TEM data were identically measured at 24 stations along 3 profiles trending NE-SW with the elongation of the study area. The measuring points were arranged in a gridlike pattern with both inter-station spacing and line-line distance of about 2 km. After performing the necessary processing steps, the VES and TEM data sets were inverted individually to multi-layer models, followed by a joint inversion of both data sets. Joint inversion process has succeeded to overcome the model-equivalence problem encountered in the inversion of individual data set. Then, the joint models were used for the construction of a number of cross sections and contour maps showing the lateral and vertical distribution of the geoelectrical parameters in the subsurface medium. Interpretation of the obtained results and correlation with the available geological and hydrogeological information revealed TWO aquifer systems in the area. The shallow Pleistocene aquifer * Corresponding author.
From the previous results, the Cairo area is said to be an active zone and recommendation is give... more From the previous results, the Cairo area is said to be an active zone and recommendation is given to decision makers for the high hazards that Cairo suffers.
According to some new discoveries at Tap-Osiris Magna temple (West of Alexandria), there is poten... more According to some new discoveries at Tap-Osiris Magna temple (West of Alexandria), there is potentiality to uncover a remarkable archeological finding at this site. Three years ago many significant archeological evidences have been discovered sustaining the idea that the tomb of Cleopatra and Anthony may be found in the Osiris temple inside Tap-Osiris Magna temple at a depth from 20 to 30 m. To confirm this idea, PHASE I was conducted in by joint application of Ground Penetrating Radar ''GPR'', Electrical Resistivity Tomography ''ERT'' and Magnetometry. The results obtained from PHASE I could not confirm the existence of major tombs at this site. However, small possible cavities were strongly indicated which encouraged us to proceed in investigation of this site by using another geophysical approach including Very Low Frequency Electro Magnetic (VLF-EM) technique. VLF-EM data were collected along parallel lines covering the investigated site with a line-to-line spacing of 1 m. The point-to-point distance of 1 m along the same line was employed. The data were qualitatively interpreted by Fraser filtering process and quantitatively by 2-D VLF inversion of tipper data and forward modeling. Results obtained from VLF-EM interpretation are correlated with 2-D resistivity imaging and drilling information. Findings showed a highly resistive zone at a depth extended from about 25-45 m buried beneath Osiris temple, which could be indicated as the tomb of Cleopatra and Anthony. This result is supported by Fraser filtering and forward modeling results. The depth of archeological findings as indicated from the geophysical survey is correlated
Magnetotelluric (MT) soundings and gravity methods were employed to study the deep freshwater aqu... more Magnetotelluric (MT) soundings and gravity methods were employed to study the deep freshwater aquifer in the area north of Abo Zenema city on the eastern side of the Gulf of Suez, Egypt. Seven MT sites and 48 gravity stations were surveyed along northeast-southwest profiles as close as possible to a line perpendicular to the coast of the Gulf of Suez.
Continuous evaluation of groundwater aquifers in the basin of Kharga Oasis is very important. Gro... more Continuous evaluation of groundwater aquifers in the basin of Kharga Oasis is very important. Groundwater in Kharga Oasis represents the major factor for the development plans of this area as it is the sole source for water supplies required for drinking and irrigation purposes. This study is concerned by analyzing the groundwater potentiality of the shallow aquifer at the northern part of Kharga basin by integrated application of Vertical Electrical Sounding (VES) and Time domain Electromagnetic (TEM) techniques. The VES data were measured at 28 points arranged along a north-south trending line by applying Schlumberger array with a maximum current-electrode spacing (AB) of 1000 m. The TEM data were measured at 167 points arranged along 11 east-west trending lines by using a single square loop with 50 m loop-side length. The VES and TEM data have been individually inverted, where the VES models were used as initial models for TEM data inversion. The final models were used for construction of 17 geoelectrical sections and 5 contour maps describing subsurface water-bearing layers at the investigated area. Correlation of the obtained models with geologic, hydrogeologic and borehole information indicates that the shallow aquifer comprises two zones (A-up) and (B-down) separated by a highly conductive shale layer. The upper zone (A) is composed of fine to medium sand with thin clay intercalations. It exhibits low to moderate resistivities. This zone was detected at depth values ranging from 10 to 70 m below ground surface (bgs) and shows a thickness of 25-90 m. The lower zone (B) exhibits moderate to high resistivity values with expected good water quality. The upper surface of zone B was detected at 60-165 m depth.
Journal of the Association of Arab Universities for Basic and Applied Sciences, Apr 1, 2013
The flood plain of the Nile River has been a safe dwelling throughout history. Recently with a gr... more The flood plain of the Nile River has been a safe dwelling throughout history. Recently with a growing population and vast growing urbanization some buildings have started to experience structural damages, which are not related to their construction design, but rather to the ground conditions around the buildings' foundations. Variations in properties of the soil supporting the buildings' foundations such as soil bearing capacity, moisture content and scouring may eventually lead to the failure of these buildings. This study is attempting to characterize the variations in the soil properties around the City Star shopping mall, in eastern Cairo, where a large building has tilted over the past few years. This tilting may lead to the collapse of the whole building if it continues at the same rate. An integrated geophysical investigation including multi-channel analysis of surface wave (MASW), ground penetrating radar (GPR) and 2-D electrical resistivity tomography (ERT) was used around the affected building to help detect possible causes of deterioration. The GPR data showed a soil-fill layer overlaying a thick bottom layer of higher moisture content. The MASW data revealed a middle layer of relatively low shear wave velocity sandwiched between two relatively high shear wave velocity layers. The ERT data showed an upper low resistivity layer overlying a high resistivity layer. Integrating the interpretations of the three geophysical methods provide a combined model that reflects lateral and vertical variation in the soil properties. This variation becomes dramatic near the tilted corner of the building.
Abstract The integration of geophysical data with direct hydrogeological measurements can provide... more Abstract The integration of geophysical data with direct hydrogeological measurements can provide a minimally invasive approach to characterize the subsurface at a variety of resolutions and over many spatial scales. The field of hydrogeophysics has attracted much attention during the ...
This study integrates remote sensing and geophysical data to identify the hydrological conditions... more This study integrates remote sensing and geophysical data to identify the hydrological conditions of the Naqab reservoir watershed. The main objectives of this study are identification and the interpretation of subsurface structures and their impact on groundwater flow, the relationships between structures and groundwater and the optimum way for watershed management in this subbasin. Geophysical data including, ground magnetic survey and 1D electrical resistivity sounding helped in identifying the lithology and delineating zones of groundwater occurrence. The magnetic data delineated the basement rock, aided in characterizing the geometry of the subsurface structures that control the land surface features and constrain groundwater flow system. The interpreted subsurface structure elements include six sets of faults trending NE-SW, NW-SE, NWW-SEE, NEE-SWW, N-S and E-W. The basement depth was estimated at zero at the southern part and about 5187 m at the northern part. Two aquifer systems were characterized, the shallow aquifer of the Wata Formation (Upper Cretaceous) and the deep aquifer of the Malha Formation (Lower Cretaceous). The probability of groundwater occurrence increases towards the central part of the study area to north direction, where the thickness of the sedimentary basin reaches its maximum at the center of the study area. Different trends of faults were interpreted from the geoelectrical cross-sections along two transects. Three patterns of faults were characterized including step faults, graben faults and horst faults. These faults could be indicated on the geo-electrical section by a marked difference in the layers` thicknesses. The magnetic data confirmed the locations of the faults delineated by the electrical resistivity profiles. The outlined faults are trending mainly in NE-SW, NW-SE, NWW-SEE, NEE-SWW and E-W directions. Lineament structures delineation and drainage pattern analysis were evaluated and interpreted from the analysis of remote sensing (RS) data and geographic information system (GIS) technique. The SRTM-DEM (Shuttle Radar Topographic Mission-Digital Elevation Model) was also utilized to automatically identify and extract drainage network. Interpretation and analysis of the inferred lineament structures indicate the presence of a number of main lineament populations that trends: NE-SW, NW-SE, NNW-SSE, NWW-SEE, E-W and N-S. Meanwhile, the interpretation and analysis of drainage pattern network indicate the presence of three main lineament structures that trends: NW-SE, NE-SW and NWW-SEE. Azimuth distribution analysis of both the measured structures and drainage channels shows similar trends, except for very few differences in the prevailing trends. Similarity in orientation of lineament structures, drainage system, and subsurface structural trends were recognized in the area under study. In conclusion, the integration between remote sensing and geophysical data revealed a close matching between the surface structural lineaments and subsurface structural trends could be verified. The preferred conduits of surface runoff and groundwater flow, as well as, the proper locations for groundwater exploitation could be determined.
Electrical resistivity survey in the form of vertical electrical sounding was conducted at the 10... more Electrical resistivity survey in the form of vertical electrical sounding was conducted at the 10th of Ramadan City, Egypt, to analyse subsurface lithology distribution and the interrelation between the possible infiltrated wastewater from oxidation ponds and the surface seepage emerged at the city centre. Special interest was paid for tracing the low-resistivity clayey layer, which can act as a barrier against surface water percolation and as a low permeable zone to form local perched water system. Vertical electrical sounding data by Schlumberger electrode configuration were taken at 17 stations along a line extended from the city centre to the oxidation ponds used for wastewater treatment. The data were inverted by using 1D and 2D inversion schemes to construct geoelectrical cross section along the surveyed line. The geoelectrical layers were interpreted principally in terms of lithology and water content by correlation with borehole information. From the obtained results, four layers were identified in the subsurface medium. The upper three layers are located above the regional water table, whereas the fourth one was interpreted to be fully water saturated. The second layer from the surface is of great importance as it is the low-resistivity clayey layer. This layer is discontinuous along the survey line. Downward infiltration of wastewater from the oxidation ponds is possible especially at the pond No. 2 as the clayey layer was interpreted not to exist at the site. The infiltrated wastewater from the oxidation ponds was interpreted not to be the cause of the surface seepage emerged at the city centre because the clayey layer dips toward opposite direction. The probable sources of the seepage were considered the local surface infiltration from excess irrigation water in the nearby cultivated land and/or leakage from the underground water utilities in the city centre. the environment (EMG 1997). The cumulative impact of industrial discharges to the ambient environment can pollute water that is used for drinking and air that is breathed by workers and residents of these cities. The 10th of Ramadan City, the present case study, is the oldest and largest industrial city in Egypt. It was constructed at the eastern fringe of the Nile Delta region, along the Cairo-Ismailia desert road, between latitudes 30° 15` and 30° 25` N and longitudes 31° 37` and 31° 52 E (Fig. 1). The city is located in lack of surface water resources; therefore, it depends on groundwater as a main source for water supplies needed for drinking and agricultural and industrial activities. A Quaternary aquifer is the main groundwater reservoir in this area. It is composed of graded sand and gravel with clay intercalations. The industrial activities in the city release various solid, liquid, and gaseous wastes. Moreover, the city has attracted a
This study integrates remote sensing and geophysical data to identify the hydrological conditions... more This study integrates remote sensing and geophysical data to identify the hydrological conditions of the Naqab reservoir watershed. The main objectives of this study are identification and the interpretation of subsurface structures and their impact on groundwater flow, the relationships between structures and groundwater and the optimum way for watershed management in this sub-basin. Geophysical data including, ground magnetic survey and 1D electrical resistivity sounding helped in identifying the lithology and delineating zones of groundwater occurrence. The magnetic data delineated the basement rock, aided in characterizing the geometry of the subsurface structures that control the land surface features and constrain groundwater flow system. The interpreted subsurface structure elements include six sets of faults trending NE-SW, NW-SE, NWW-SEE, NEE-SWW, N-S and E-W. The basement depth was estimated at zero at the southern part and about 5187 m at the northern part. Two aquifer sy...
East Cairo is characterized by abundant quarries that have been used as landfill sites for solid ... more East Cairo is characterized by abundant quarries that have been used as landfill sites for solid waste. These sites have become part of the urban sprawl of New Cairo, and their detection became difficult from the ground surface. In this study, analysis of multi-temporal high-resolution satellite images and electrical resistivity tomography (ERT) data were used to detect and delineate a buried landfill site located near the Ring Road, East Cairo, Egypt. Analysis of changes detected on the satellite images revealed that the study site was a WNW-oriented Quarry until 2005 and then randomly filled with heterogeneous solid materials. ERT survey was planned based on the result of change detection. On the plan view, the ERT measurements have outlined the electrically conductive zones which are occupied by filling material and distinguished them from the resistive zones that symbolize the natural soil areas. By assimilation of the satellite images and the ERT results, two distinguished geoe...
Transient ElectroMagnetic (TEM) sounding and Ground ElectroMagnetic (GEM) profiling have been con... more Transient ElectroMagnetic (TEM) sounding and Ground ElectroMagnetic (GEM) profiling have been conducted at Hawara archeological area, El Fayoum, Egypt to investigate the subsurface water and its effect on the archeological targets at this area. This archeological site comprises Hawara pyramid, the northern necropolis and a southern mortuary complex called “labyrinth”. Nowadays Hawara area is entirely abandoned and surrounded by cultivated areas, as well as, a surface water canal named “Bahr Wahba”. The surface and underground water bodies have negative effects on the foundation of Hawara pyramid and the labyrinth site, where the entrance of the pyramid is today flooded to a depth of about 6 meters below the ground surface. TEM data have been acquired at three sites in this area comprising the cultivated land, the pyramid and the labyrinth, while the GEM survey was conducted inside the labyrinth site. Integrated interpretation of these data sets indicates that, the agricultural activ...
The mines of magnetite and hematite occupy some areas of the Eastern Desert at Wadi Abu Subeira, ... more The mines of magnetite and hematite occupy some areas of the Eastern Desert at Wadi Abu Subeira, northeast of Aswan city which is a volcanic and tectonic area. It is one of the largest arc sedimentary rock sequence affected by faulting and folding due to repeated stages of deformation. The iron deposits in this area are of oolitic type and exist in two bands inter-bedded with ferruginous sandstone and clay layers. The thickness of the bands varies from 0.5 to 3.5 m. Detailed geophysical work has been carried out on the promise site of Abu Subeira to identify the lateral and vertical distribution of the iron-ore deposits at this area. Many geophysical methods were applied in this study including Land Magnetic Survey, Electrical Resistivity Imaging (ERI), Induced Polarization (IP), and Time-Domain Electromagnetic (TDEM). Besides, rock samples from the iron ores were collected for chemical analysis. The X-ray fluorescence (XRF) and X-ray diffraction (XRD) techniques were applied for estimation of iron concentration (Fe %) and other minerals’ contents in the rock samples. The field data sets were measured along the iron ore bodies of Wadi Abu Subeira and were processed and analyzed by the proper software packages. The areas with iron ore deposits were expressed in the geophysical results by low resistivity, high chargeability, and moderate to high magnetic anomalies. Integrated interpretation of the obtained results revealed that the ore deposits exist in the form of lenses with variable thickness ranging from few meters to about 30-m thick. The mineral occurrences in Abu Subeira are managed by the major faults and the hydrothermal fluids flowing along these faults.
Vertical Electrical Sounding (VES) and Transient ElectroMagnetic (TEM) survey have been applied f... more Vertical Electrical Sounding (VES) and Transient ElectroMagnetic (TEM) survey have been applied for characterizing the groundwater aquifers at El Sadat industrial area. El-Sadat city is one of the most important industrial cities in Egypt. It has been constructed more than three decades ago at about 80 km northwest of Cairo along the Cairo-Alexandria desert road. Groundwater is the main source of water supplies required for domestic, municipal and industrial activities in this area due to the lack of surface water sources. So, it is important to maintain this vital resource in order to sustain the development plans of this city. In this study, VES and TEM data were identically measured at 24 stations along 3 profiles trending NE-SW with the elongation of the study area. The measuring points were arranged in a gridlike pattern with both inter-station spacing and line-line distance of about 2 km. After performing the necessary processing steps, the VES and TEM data sets were inverted individually to multi-layer models, followed by a joint inversion of both data sets. Joint inversion process has succeeded to overcome the model-equivalence problem encountered in the inversion of individual data set. Then, the joint models were used for the construction of a number of cross sections and contour maps showing the lateral and vertical distribution of the geoelectrical parameters in the subsurface medium. Interpretation of the obtained results and correlation with the available geological and hydrogeological information revealed TWO aquifer systems in the area. The shallow Pleistocene aquifer * Corresponding author.
From the previous results, the Cairo area is said to be an active zone and recommendation is give... more From the previous results, the Cairo area is said to be an active zone and recommendation is given to decision makers for the high hazards that Cairo suffers.
According to some new discoveries at Tap-Osiris Magna temple (West of Alexandria), there is poten... more According to some new discoveries at Tap-Osiris Magna temple (West of Alexandria), there is potentiality to uncover a remarkable archeological finding at this site. Three years ago many significant archeological evidences have been discovered sustaining the idea that the tomb of Cleopatra and Anthony may be found in the Osiris temple inside Tap-Osiris Magna temple at a depth from 20 to 30 m. To confirm this idea, PHASE I was conducted in by joint application of Ground Penetrating Radar ''GPR'', Electrical Resistivity Tomography ''ERT'' and Magnetometry. The results obtained from PHASE I could not confirm the existence of major tombs at this site. However, small possible cavities were strongly indicated which encouraged us to proceed in investigation of this site by using another geophysical approach including Very Low Frequency Electro Magnetic (VLF-EM) technique. VLF-EM data were collected along parallel lines covering the investigated site with a line-to-line spacing of 1 m. The point-to-point distance of 1 m along the same line was employed. The data were qualitatively interpreted by Fraser filtering process and quantitatively by 2-D VLF inversion of tipper data and forward modeling. Results obtained from VLF-EM interpretation are correlated with 2-D resistivity imaging and drilling information. Findings showed a highly resistive zone at a depth extended from about 25-45 m buried beneath Osiris temple, which could be indicated as the tomb of Cleopatra and Anthony. This result is supported by Fraser filtering and forward modeling results. The depth of archeological findings as indicated from the geophysical survey is correlated
Magnetotelluric (MT) soundings and gravity methods were employed to study the deep freshwater aqu... more Magnetotelluric (MT) soundings and gravity methods were employed to study the deep freshwater aquifer in the area north of Abo Zenema city on the eastern side of the Gulf of Suez, Egypt. Seven MT sites and 48 gravity stations were surveyed along northeast-southwest profiles as close as possible to a line perpendicular to the coast of the Gulf of Suez.
Continuous evaluation of groundwater aquifers in the basin of Kharga Oasis is very important. Gro... more Continuous evaluation of groundwater aquifers in the basin of Kharga Oasis is very important. Groundwater in Kharga Oasis represents the major factor for the development plans of this area as it is the sole source for water supplies required for drinking and irrigation purposes. This study is concerned by analyzing the groundwater potentiality of the shallow aquifer at the northern part of Kharga basin by integrated application of Vertical Electrical Sounding (VES) and Time domain Electromagnetic (TEM) techniques. The VES data were measured at 28 points arranged along a north-south trending line by applying Schlumberger array with a maximum current-electrode spacing (AB) of 1000 m. The TEM data were measured at 167 points arranged along 11 east-west trending lines by using a single square loop with 50 m loop-side length. The VES and TEM data have been individually inverted, where the VES models were used as initial models for TEM data inversion. The final models were used for construction of 17 geoelectrical sections and 5 contour maps describing subsurface water-bearing layers at the investigated area. Correlation of the obtained models with geologic, hydrogeologic and borehole information indicates that the shallow aquifer comprises two zones (A-up) and (B-down) separated by a highly conductive shale layer. The upper zone (A) is composed of fine to medium sand with thin clay intercalations. It exhibits low to moderate resistivities. This zone was detected at depth values ranging from 10 to 70 m below ground surface (bgs) and shows a thickness of 25-90 m. The lower zone (B) exhibits moderate to high resistivity values with expected good water quality. The upper surface of zone B was detected at 60-165 m depth.
The stable (δ2H, δ18O and δ13C) and radiocarbon (14C) isotopic compositions of water and hydroche... more The stable (δ2H, δ18O and δ13C) and radiocarbon (14C) isotopic compositions of water and hydrochemical information were analyzed and used to quantify the contribution of different sources, i.e., groundwater in the original Quaternary and the Miocene aquifers, surface water in the Ismailia canal and wastewater, to the Quaternary aquifer system. 14C activities and isotope data suggest that about 52% of groundwater in the Quaternary aquifer is derived from the past rainfall, i.e., presumably 5000-7800 years B.P. Northward (EC <1000 µS/cm, high HCO3- concentration, δ13C-depleted, δ18O/δ2H-enriched, and 14C ≥ 70 pMC) and southward (EC >6000 µS/cm, low HCO3- concentration, δ13C-enriched, δ18O/δ2H-depleted, and 14C ≤ 42 pMC) spatial changes in chemical and isotopic compositions of groundwater in the Quaternary aquifer are attributed to the contributions of the Ismailia canal in the north and the groundwater of the Miocene aquifer in the south, respectively. Temporal changes of isotopic composition of the Nile water in response to the construction of the Aswan High Dam are also detected and the information is used to evaluate the groundwater recharge processes from the Ismailia canal. Current contribution from the Ismailia canal (25%) is considered to be greatly enhanced through surface water diversion and related irrigation practices, i.e., freshwater ponds. Contribution of the groundwater from the Miocene aquifer was also detected locally, and it was thought to be related to the excessive pumping. Increase in nitrate concentrations, change in the stable isotopic composition of groundwater from wells adjacent to wastewater ponds, along with the information obtained from the analysis of city water balance and recent geophysical data show that local recharge from wastewater ponds (4%) occurs to the Quaternary aquifer system. The results are expected to be helpful for formulating appropriate protection and sustainable water management strategies.
Uploads
Papers by Usama Massoud