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Sustainable water resources management in desert environment has yet to be reached due to the limited hydrological datasets under such extreme arid conditions. In the Eastern Sahara, the tectonic activity associated with the opening of the Red Sea adds more complexity to developing sustainable water management by creating multiple aquifers within subsided half-grabens along the Red Sea extension. To overcome these difficulties, a two-fold approach is adopted including integrated remote sensing and geoelectrical methods using Wadi Al-Ambagi watershed in the Eastern Desert of Egypt as a test site. First, the total discharge is estimated as 15.7 × 106 m3 following the application of a uniform storm of 10 mm effective precipitation, which exceeds the storage capacity of existing mitigation measures (5.5 × 106 m3), and thus additional dams are required. Second, the subsurface geometry of alluvium and sedimentary aquifers, within subsided blocks in the Arabian–Nubian shield (ANS), is delineated using 1D direct current and 2D electrical-resistivity tomography (ERT). Findings indicate that significant thicknesses of more than 80 m of permeable sedimentary units occur within the subsided blocks. Therefore, the scarce water resources can be managed by controlling the flash floods and suggesting proper dam sites at the location of thick alluvium and sedimentary rocks, where aquifers can be recharged representing a sustainable source for freshwater. The proposed approach is transferable and can be applied in similar arid rift-related watersheds in Saudi Arabia and worldwide.
Mohamed Attwa; Mohammed El Bastawesy; Dina Ragab; Abdullah Othman; Hamza M. Assaggaf; Abotalib Z. Abotalib. Toward an Integrated and Sustainable Water Resources Management in Structurally-Controlled Watersheds in Desert Environments Using Geophysical and Remote Sensing Methods. Sustainability 2021, 13, 4004 .
AMA StyleMohamed Attwa, Mohammed El Bastawesy, Dina Ragab, Abdullah Othman, Hamza M. Assaggaf, Abotalib Z. Abotalib. Toward an Integrated and Sustainable Water Resources Management in Structurally-Controlled Watersheds in Desert Environments Using Geophysical and Remote Sensing Methods. Sustainability. 2021; 13 (7):4004.
Chicago/Turabian StyleMohamed Attwa; Mohammed El Bastawesy; Dina Ragab; Abdullah Othman; Hamza M. Assaggaf; Abotalib Z. Abotalib. 2021. "Toward an Integrated and Sustainable Water Resources Management in Structurally-Controlled Watersheds in Desert Environments Using Geophysical and Remote Sensing Methods." Sustainability 13, no. 7: 4004.
Flash flood hazard assessments, mitigation measures, and water harvesting efforts in desert environments are often challenged by data scarcity on the basin scale. The present study, using the Wadi Atfeh catchment as a test site, integrates remote sensing datasets with field and geoelectrical measurements to assess flash flood hazards, suggest mitigation measures, and to examine the recharge to the alluvium aquifer. The estimated peak discharge of the 13 March 2020 flood event was 97 m3/h, which exceeded the capacity of the culverts beneath the Eastern Military Highway (64 m3/h), and a new dam was suggested, where 75% of the catchment could be controlled. The monitoring of water infiltration into the alluvium aquifer using time-lapse electrical resistivity measurements along a fixed profile showed a limited connection between the wetted surficial sediments and the water table. Throughflow is probably the main source of recharge to the aquifer rather than vertical infiltration at the basin outlet. The findings suggest further measures to avoid the negative impacts of flash floods at the Wadi Atfeh catchment and similar basins in the Eastern Desert of Egypt. Furthermore, future hydrological studies in desert environments should take into consideration the major role of the throughflow in alluvium aquifer recharge.
Omnia El-Saadawy; Ahmed Gaber; Abdullah Othman; Abotalib Z. Abotalib; Mohammed El Bastawesy; Mohamed Attwa. Modeling Flash Floods and Induced Recharge into Alluvial Aquifers Using Multi-Temporal Remote Sensing and Electrical Resistivity Imaging. Sustainability 2020, 12, 10204 .
AMA StyleOmnia El-Saadawy, Ahmed Gaber, Abdullah Othman, Abotalib Z. Abotalib, Mohammed El Bastawesy, Mohamed Attwa. Modeling Flash Floods and Induced Recharge into Alluvial Aquifers Using Multi-Temporal Remote Sensing and Electrical Resistivity Imaging. Sustainability. 2020; 12 (23):10204.
Chicago/Turabian StyleOmnia El-Saadawy; Ahmed Gaber; Abdullah Othman; Abotalib Z. Abotalib; Mohammed El Bastawesy; Mohamed Attwa. 2020. "Modeling Flash Floods and Induced Recharge into Alluvial Aquifers Using Multi-Temporal Remote Sensing and Electrical Resistivity Imaging." Sustainability 12, no. 23: 10204.
An integrated approach is carried out to study the hydrogeological conditions in wadi systems. In this chapter, the use of remote sensing and direct current (DC) resistivity techniques was considered to manage the flash flood and explore groundwater in desert lands. As case studies, two wadis at the Eastern and Western Deserts, Egypt, are presented to show the efficiency of using the suggested integrated study. Based on satellite images, remote sensing (RS) and geographic information system (GIS) techniques are used to identify the regional geology, geomorphological features, lineaments, and active channels regarding flash flood events in desert lands. Consequently, a hydrograph and runoff modeling can be estimated for wadi systems. Furthermore, the calculated flash flood total discharges and the storage capacity of existing mitigation measures can be recognized. From a geophysical point of view, the DC resistivity method can be applied to identify the subsurface layer distributions, image the near-surface lateral heterogeneities, subsurface structures, and potential groundwater zones. Based on geophysical data inversion results, this chapter shows that it is possible to recognize sites for successful dam construction and groundwater bearing zones exploration. Accordingly, the results of these case studies represent the importance of the integrated approach for the flash flood hazards management and its harvesting.
Mohamed Attwa; Dina Ragab; Mohammed El Bastawesy; Ahmed M. Abd El-Fattah. Flash Flood Management and Harvesting Via Groundwater Recharging in Wadi Systems: An Integrative Approach of Remote Sensing and Direct Current Resistivity Techniques. Plant-Microbes-Engineered Nano-particles (PM-ENPs) Nexus in Agro-Ecosystems 2020, 107 -119.
AMA StyleMohamed Attwa, Dina Ragab, Mohammed El Bastawesy, Ahmed M. Abd El-Fattah. Flash Flood Management and Harvesting Via Groundwater Recharging in Wadi Systems: An Integrative Approach of Remote Sensing and Direct Current Resistivity Techniques. Plant-Microbes-Engineered Nano-particles (PM-ENPs) Nexus in Agro-Ecosystems. 2020; ():107-119.
Chicago/Turabian StyleMohamed Attwa; Dina Ragab; Mohammed El Bastawesy; Ahmed M. Abd El-Fattah. 2020. "Flash Flood Management and Harvesting Via Groundwater Recharging in Wadi Systems: An Integrative Approach of Remote Sensing and Direct Current Resistivity Techniques." Plant-Microbes-Engineered Nano-particles (PM-ENPs) Nexus in Agro-Ecosystems , no. : 107-119.
Wastewater leakage problem associated with sewage treatment plants deterioration has become prominent. We develop and apply procedures of GIS and direct current resistivity (DCR) techniques to investigate the wastewater seepage appearance in a semiarid urban environment. In the first stage, all surface geological and structural information is manipulated using GIS to produce geomorphological and geological maps. Waterlogged sites resulting in land degradation are distinguished by monitoring land-use/land-cover (LU/LC) changes. In the second stage, the DCR method has been performed to characterize the subsurface layer distributions and structures considering the results of GIS and LU/LC mapping data. Because the geophysical inverse problem is usually ill-posed, the active constrain balancing (ACB) approach and genetic algorithms (GA) are applied to optimize the inversion results. In the presence of high conductive layers, the limitation of DCR imaging in detecting the subsurface structure is demonstrated from the synthetic data. Moreover, we demonstrate that the joint use of GA with structure-based model (SBM) is helpful in recognition of subsurface layer distributions with non-smooth interfaces. However, ACB approach is more practical for lateral heterogeneities determination within the same rock unit than SBM with GA approach. The results indicate that the waterlogged areas and wastewater migration pathways are mainly controlled by the drainage networks and subsurface structures. Notably, the integrated approach allows us to assess geotechnical problems and to propose a suitable location for wastewater discharge management. Finally, the study can be considered as a scientific basis for desert urbanization and rational urban development planning.
Mohamed Attwa; Sara Zamzam. An integrated approach of GIS and geoelectrical techniques for wastewater leakage investigations: Active constraint balancing and genetic algorithms application. Journal of Applied Geophysics 2020, 175, 103992 .
AMA StyleMohamed Attwa, Sara Zamzam. An integrated approach of GIS and geoelectrical techniques for wastewater leakage investigations: Active constraint balancing and genetic algorithms application. Journal of Applied Geophysics. 2020; 175 ():103992.
Chicago/Turabian StyleMohamed Attwa; Sara Zamzam. 2020. "An integrated approach of GIS and geoelectrical techniques for wastewater leakage investigations: Active constraint balancing and genetic algorithms application." Journal of Applied Geophysics 175, no. : 103992.
Nowadays, geo-environmental assessment becomes an immediate concern all over the world. In general, the flow paths of pollutants and radioactive source allocations are related to rock types, subsurface layer distributions and structural settings. Thus, this chapter aims to present a non-conventional integrative approach of remote sensing, structural data and geophysical methods for geo-environmental hazard assessment. Notably, such hazards commonly result from human activities where contaminants are accumulated and spread on or beneath the ground surface. Detection of organic contamination and hydrocarbon flow path is a difficult task for geophysical techniques at hazardous waste areas. Furthermore, radioactive-emission detection is of specific value in the vicinity of mineral resources for human health and environmental preservation. Accordingly, waste management as well as a subsurface contaminant and geological structure mapping are prerequisite for urbanization, mining and civil engineering. In this chapter, we presented cases for waste management to indicate how recent technologies can be used for detection and prediction of geo-environmental hazards in urban areas and desert lands. The following techniques are used to achieve the objective of the chapter: (1) remote sensing, (2) information on structural geology, (3) direct current (DC) resistivity method and (4) airborne geophysics. Regarding four case studies, the results indicate the effectiveness of the suggested approach to map surface and subsurface geological conditions concerning the pollutants and radioactive emissions in 2D/3D. Even when the contaminant itself produces no detectable direct geophysical signature, sometimes it may be found by indirect means through the structural mapping as a guide to predict the contaminant flow paths. Accordingly, the approach will be helpful to the decision-makers to achieve sustainable development in urban and desert areas regarding the waste management aspects. Moreover, the present nondestructive approach can be considered as an initial step in waste assessment projects.
Mohamed Attwa; Ahmed Henaish; Sara Zamzam. Detection and Prediction of Geo-environmental Hazards in Urban Areas and Desert Lands Using an Integrated Structural and Geophysical Approach: Cases from Egypt. Springer Water 2019, 71 -92.
AMA StyleMohamed Attwa, Ahmed Henaish, Sara Zamzam. Detection and Prediction of Geo-environmental Hazards in Urban Areas and Desert Lands Using an Integrated Structural and Geophysical Approach: Cases from Egypt. Springer Water. 2019; ():71-92.
Chicago/Turabian StyleMohamed Attwa; Ahmed Henaish; Sara Zamzam. 2019. "Detection and Prediction of Geo-environmental Hazards in Urban Areas and Desert Lands Using an Integrated Structural and Geophysical Approach: Cases from Egypt." Springer Water , no. : 71-92.
The coastal and alluvial areas of the Red Sea Mountains are mainly being developed for resorts and tourism activities. Given the development of occasional flash floods in the central part of the Red Sea area can be of destructive consequences to the various anthropogenic activities; thus the quantitative and qualitative assessments of the hydrological parameters and groundwater occurrence are presented. As a case study, Wadi Isl at the Red Sea coast has been hydrogeologically analyzed using an integrative approach of remote sensing, GIS and direct current resistivity (DCR) tools. The time area-zones have been estimated using and Manning's equation into the spatial analyses routines embedded within the ArcGIS. In this study, a synthetic effective rainfall of 10 mm has been applied to compute the spatially distributed runoff hydrograph. The estimated total runoff volume is approximately 8 million cubic meters, and the peak discharge rate is estimated to 163 cubic meters per second, which can be destructive to the main infrastructures in the flash flood pathways. Then, the 2D-electrical resistivity tomography (2D-ERT) surveys have been carried out at various localities along the main wadi course to explore the lateral and vertical variation of alluvium thickness and the saturated zones. Notably, the groundwater occurrence is contained in the structurally controlled graben. Therefore, the study has recommended the construction a main barrier at a natural deep gorge of the main outlet in order to fully control the flash floods and to enhance the potential recharge to the underlying alluvium aquifer. The present integrative approach of both surface and subsurface data is definitely needed to maximize the flash flood benefits.
Mohammed El Bastawesy; Mohamed Attwa; Tharwat H. Abd El Hafeez; Ahmed Gad. Flash floods and groundwater evaluation for the non-gauged dryland catchment using remote sensing, GIS and DC resistivity data: A case study from the Eastern Desert of Egypt. Journal of African Earth Sciences 2019, 152, 245 -255.
AMA StyleMohammed El Bastawesy, Mohamed Attwa, Tharwat H. Abd El Hafeez, Ahmed Gad. Flash floods and groundwater evaluation for the non-gauged dryland catchment using remote sensing, GIS and DC resistivity data: A case study from the Eastern Desert of Egypt. Journal of African Earth Sciences. 2019; 152 ():245-255.
Chicago/Turabian StyleMohammed El Bastawesy; Mohamed Attwa; Tharwat H. Abd El Hafeez; Ahmed Gad. 2019. "Flash floods and groundwater evaluation for the non-gauged dryland catchment using remote sensing, GIS and DC resistivity data: A case study from the Eastern Desert of Egypt." Journal of African Earth Sciences 152, no. : 245-255.
Contrary to the usual application of individual geological and/or geophysical surveys, this paper represented a sequential use of surface structural mapping and DCR method to afford a sensible structural model in a cost effective way. Understanding the geological setting of a non-mapped area at the central part of Cairo-Suez District (CSD), Egypt, is an immediate engineering concern due to its complex deformation history. Field work is carried out to measure stratigraphic sections and establish structural characteristics of the rock units. Surface geophysical DCR sounding and electrical resistivity tomography (ERT) surveys are performed. To overcome the non-uniqueness problem of DCR interpretation, the available borehole data, detailed surface geological measurements and a sequential use of linear and non-linear inversion algorithms are applied. The practical benefits of detailed surface structural mapping are demonstrating in considering all geological parameters to a conceptual subsurface model, which would have not been identified or misinterpreted otherwise. In an integrative approach, such detailed surface data allow us to confirm the uncertain inferred regional subsurface structures based on DCR data inversion. For detailed subsurface structural characterization, the results of ERTs using coarse triangular mesh and iteratively reweighted algorithm show a good agreement with prior known surface and underground structural features. Additionally, ERTs significantly resolve the complex geological features, which constitute uncertain structures in the surface structural model. The main impact of presented integrative approach is to (i) constraint the DCR data interpretation and (ii) inform a preliminary study plan of regional structural investigation, which can be used as a platform for engineering decision–making and/or further detailed geophysical and geotechnical investigations.
Mohamed Attwa; Ahmed Henaish. Regional structural mapping using a combined geological and geophysical approach – A preliminary study at Cairo-Suez district, Egypt. Journal of African Earth Sciences 2018, 144, 104 -121.
AMA StyleMohamed Attwa, Ahmed Henaish. Regional structural mapping using a combined geological and geophysical approach – A preliminary study at Cairo-Suez district, Egypt. Journal of African Earth Sciences. 2018; 144 ():104-121.
Chicago/Turabian StyleMohamed Attwa; Ahmed Henaish. 2018. "Regional structural mapping using a combined geological and geophysical approach – A preliminary study at Cairo-Suez district, Egypt." Journal of African Earth Sciences 144, no. : 104-121.
The current study presents a new integrative approach for detailed structural mapping of a soft-linkage transfer zone using outcrop, boreholes and DCR data in the form of soundings and 2D-electrical resistivity tomography (2D-ERT). As a case study, the present approach is implied for studying the geo-engineering conditions of a highly deformed desert-land entry to reclaim at Cairo-Suez district, Egypt. The approach has led to the spatial understanding of the subsurface heterogeneity and complex structures at a level of accuracy unattainable with traditional surface structural mapping alone. For preliminary geotechnical assessment, some physical and geotechnical properties are characterized by field and laboratory measurements for collected soil samples. Moreover, the inverted DCR data are used to predict the RQD values using a polynomial relationship between RQD and the intrinsic resistivity (ρ). Notably, the calculated and actual values of RQD are, in general, in the same order considering the error factor value, and hence, the derived equation for RQD prediction is satisfactory. Therefore, the proposed approach reduces the uncertainty of the constructed structural model for engineering design. In addition, merging outcrop with DCR data allows us with a limited frame of time to partially mitigate disasters to civilization by better (i) potential location understanding and (ii) remediation plans tuning for a complex structured site.
Ahmed Henaish; Mohamed Attwa. Internal structural architecture of a soft-linkage transfer zone using outcrop and DC resistivity data: Implications for preliminary engineering assessment. Engineering Geology 2018, 244, 1 -13.
AMA StyleAhmed Henaish, Mohamed Attwa. Internal structural architecture of a soft-linkage transfer zone using outcrop and DC resistivity data: Implications for preliminary engineering assessment. Engineering Geology. 2018; 244 ():1-13.
Chicago/Turabian StyleAhmed Henaish; Mohamed Attwa. 2018. "Internal structural architecture of a soft-linkage transfer zone using outcrop and DC resistivity data: Implications for preliminary engineering assessment." Engineering Geology 244, no. : 1-13.
In coastal and semiarid regions, the scientific interest lies in imaging the saltwater intrusion and delineating freshwater aquifer zones, respectively. Direct current resistivity (DCR) and induced polarization (IP) geophysical methods are commonly used to assess hydraulic characteristics of the aquifer. Particularly, the main reason for hydrogeophysical application of both DCR and IP is that the electrical characteristics of aquifers depend mainly on the geometry of the pore space and the porosity controlling the soil and rock effective transport properties. For preliminary hydrogeological investigations, these methods are applied at a wide range of field and laboratory scales. Accordingly, the vulnerable zone to the saltwater intrusion and/or contamination can be characterized by high accuracy. Furthermore, empirical and semiempirical relationships are widely used to predict the aquifer petrophysical characteristics, e.g., hydraulic conductivity, using the inversion results of such electrical methods. Equally, conventional and nonconventional DCR inversion algorithms are developed to reduce the nonuniqueness problem of actual resistivity interpretation and, consequently, to obtain more meaningful models than previously reported. As case histories, this chapter demonstrates the efficiency of DCR method for hydrogeological assessment in Nile Delta, Egypt, emphasizing on technical constraints to achieve sustainable development in coastal and semiarid areas.
Mohamed Attwa; Halim Ali. Resistivity Characterization of Aquifer in Coastal Semiarid Areas: An Approach for Hydrogeological Evaluation. The Handbook of Environmental Chemistry 2018, 213 -233.
AMA StyleMohamed Attwa, Halim Ali. Resistivity Characterization of Aquifer in Coastal Semiarid Areas: An Approach for Hydrogeological Evaluation. The Handbook of Environmental Chemistry. 2018; ():213-233.
Chicago/Turabian StyleMohamed Attwa; Halim Ali. 2018. "Resistivity Characterization of Aquifer in Coastal Semiarid Areas: An Approach for Hydrogeological Evaluation." The Handbook of Environmental Chemistry , no. : 213-233.
The objective of this study is to evaluate the effectiveness of DC resistivity surveys for imaging the wastewater percolation around the stabilization ponds in the Tenth of Ramadan City, the desert fringes of East Nile Delta, Egypt. Detailed resistivity surveys, including DC soundings and electrical resistivity tomography (ERT), were carried out along several profiles. Furthermore, synthetic modeling of ERT was designed to optimize the survey configurations and interpretation of the results. A 2D modeling of smoothness-constrained least-squares inversion scheme was applied to delineate the possible wastewater infiltration zones from oxidation ponds. Because the geoelectrical interpretation has a degree of non-uniqueness, the resistivity inversion was constrained using borehole lithological information and soil sample laboratory measurements. The DC inversion results indicate decreasing resistivity down to a depth of 15 m around waste disposal sites. The inferred soil zone close to the oxidation ponds was a mixture of sand, silt and clay. Moreover, the clay minerals were characterized by moderate swelling that could have reduced the vertical infiltration speed, causing wastewater seepage, especially around unlined disposal sites and open surface drains. Accordingly, the medium-to-low resistivity values can be attributed to wastewater leakage in clayey sand soil. Because the area slopes generally toward the northeast, the surface seepage was dominant in the shallow impermeable sandy clay subsoil. Therefore, measuring soil parameters is a complementary method to optimize resistivity interpretation, with potential for mitigating environmental hazards from wastewater leakage around disposal ponds.
Khaled S. Gemail; Mohamed Attwa; Mohamed Eleraki; Sara Zamzam. Imaging of wastewater percolation in heterogeneous soil using electrical resistivity tomography (ERT): a case study at east of Tenth of Ramadan City, Egypt. Environmental Earth Sciences 2017, 76, 666 .
AMA StyleKhaled S. Gemail, Mohamed Attwa, Mohamed Eleraki, Sara Zamzam. Imaging of wastewater percolation in heterogeneous soil using electrical resistivity tomography (ERT): a case study at east of Tenth of Ramadan City, Egypt. Environmental Earth Sciences. 2017; 76 (19):666.
Chicago/Turabian StyleKhaled S. Gemail; Mohamed Attwa; Mohamed Eleraki; Sara Zamzam. 2017. "Imaging of wastewater percolation in heterogeneous soil using electrical resistivity tomography (ERT): a case study at east of Tenth of Ramadan City, Egypt." Environmental Earth Sciences 76, no. 19: 666.
Scientific interest within the desert-lands lies on mapping the near-surface clayey soils being made environmental engineering problems, e.g., water logging and cracked pavements. As a starting point used for urban rational development, boreholes, direct current resistivity (DCR) soundings and electrical resistivity tomography surveys and preliminary geotechnical studies are employed in an integrative approach for mapping and characterizing the foundation soil. This study is carried out at one of the main urban reclamation projects amidst desert fringes of East Nile Delta, Egypt, as a case study, where the in situ soil properties are variable even within a short distance and, consequently, difficult to be predicted. Conventional and non-conventional inversion approaches are applied for solving the inverse problems of DCR data. The results are calibrated with the drilled borehole lithology. Two main geoelectrical resistivity layers are distinguished: the upper medium to high-resistivity soils corresponding to surface poorly graded sand with gravels underlain by low-resistivity layer attributing to clayey sand with calcareous materials. The inversion results show the sequential joint use efficiency of the two approaches in mapping the near-surface layer boundaries providing realistic soil heterogeneities tomography. In respect of such results and from an engineering point of view, the exaggerated clayey soils are highly saturated in some places representing (1) medium plasticity, moderate-to-high swelling and (2) low compressive strength. It is conceivable that such soils can exhibit geotechnical problems, especially under wetting conditions. Consequently, the integrative approach is cost-effective and opens the way for engineers on where prioritized interventions are required to the urban expansion.
Mohamed Attwa; Abdelaziz El-Shinawi. An integrative approach for preliminary environmental engineering investigations amidst reclaiming desert-land: a case study at East Nile Delta, Egypt. Environmental Earth Sciences 2017, 76, 304 .
AMA StyleMohamed Attwa, Abdelaziz El-Shinawi. An integrative approach for preliminary environmental engineering investigations amidst reclaiming desert-land: a case study at East Nile Delta, Egypt. Environmental Earth Sciences. 2017; 76 (8):304.
Chicago/Turabian StyleMohamed Attwa; Abdelaziz El-Shinawi. 2017. "An integrative approach for preliminary environmental engineering investigations amidst reclaiming desert-land: a case study at East Nile Delta, Egypt." Environmental Earth Sciences 76, no. 8: 304.
To understand the impact of sea level rise (SLR) and aquifer intensive use would cause to the groundwater level and saltwater intrusion, an integrated relationship between salinity and electrical resistivity of a Quaternary aquifer is established in the northern part of East Nile Delta (El Sharkia area), Egypt. Historical data of groundwater salinity are mapped and compared with the current water samples to better understand the salinity spatial variability. The salinity maps show that salinization has increased sustainably. Additionally, the transition/dynamic zone related to SLR and/or excessive pumping can be addressed. In particular, the surface DC resistivity soundings were carried out to demonstrate the vertical and horizontal salinity distributions in the area. In the course of this study, the 1D model generation using a hybrid genetic algorithm (GA) was applied and tested using borehole information. The constructed geoeletrical cross-sections emphasize and delineate the extension of saltwater intrusion. Cleary, it is found that due to excessive pumping from shallow wells over the last decades, the subsurface resistivity and TDS vertical distributions can change rapidly within a short distance. Additionally, the results show that despite the dominance of brackish and saltwater at the northern part of the area, perched low conductive lenses are observed reflecting a low level of groundwater salinization. To obtain a link between water salinity and aquifer resistivity, an empirical relationship was derived to predict the salinity variations at different depths. In comparison with the measured total dissolved solids (TDS), the predicted salinity map appears realistic. These results demonstrate the important role of the integration between resistivity and salinity measurements for mapping the groundwater salinization with depth, and call for further research to plan and manage the area’s water resources.
Mohamed Attwa; Khaled S. Gemail; Mohamed Eleraki. Use of salinity and resistivity measurements to study the coastal aquifer salinization in a semi-arid region: a case study in northeast Nile Delta, Egypt. Environmental Earth Sciences 2016, 75, 1 -18.
AMA StyleMohamed Attwa, Khaled S. Gemail, Mohamed Eleraki. Use of salinity and resistivity measurements to study the coastal aquifer salinization in a semi-arid region: a case study in northeast Nile Delta, Egypt. Environmental Earth Sciences. 2016; 75 (9):1-18.
Chicago/Turabian StyleMohamed Attwa; Khaled S. Gemail; Mohamed Eleraki. 2016. "Use of salinity and resistivity measurements to study the coastal aquifer salinization in a semi-arid region: a case study in northeast Nile Delta, Egypt." Environmental Earth Sciences 75, no. 9: 1-18.
This study is a trial to predict the relationship between the formation resistivity data and some petrophysical properties of rocks in Tut and Khalda oil fields at the northern Western Desert, Egypt. First, the deep resistivity (deep laterolog (LLD)) and gamma ray (GR) logs are smoothed by a linear combination of simple fitting functions that satisfy the smoothness criteria, and consequently the behavior of both logs can be simulated. Next, the smoothed log data are divided into branches, where high and frequent excursions in GR and LLD logs occur. In subsequent steps, the Dar-Zarrouk parameters are calculated and followed by a smoothing process for each branch. Based on a visual inspection of these parameters with effective porosity logs, the Dar-Zarrouk parameters are divided into zones and then interpreted in terms of shale content and the potentiality of the two oil fields. The permeability trend observed in core samples showed that the calculated parameters provide an adequate qualitative prediction for the petrophysical properties including the overall permeability trends. Despite the fact that the predicted permeability trends in Khalda oil field coincides with those measured from core samples, a weak correlation is observed, which can be attributed to the reservoir heterogeneity with dominance of laminated and dispersed shale and/or iron oxides. The potentiality of the proposed method lies in its simplicity, requiring only GR, LLD, and effective porosity logs. However, it would be more meaningful if the above method is tested in areas with diverse geological environment.
Mohamed Attwa; Muhammad Nabih. Prediction of permeability anisotropy using Dar-Zarrouk parameters of deep resistivity logs: a case study in the northern Western Desert of Egypt. Arabian Journal of Geosciences 2015, 8, 10497 -10508.
AMA StyleMohamed Attwa, Muhammad Nabih. Prediction of permeability anisotropy using Dar-Zarrouk parameters of deep resistivity logs: a case study in the northern Western Desert of Egypt. Arabian Journal of Geosciences. 2015; 8 (12):10497-10508.
Chicago/Turabian StyleMohamed Attwa; Muhammad Nabih. 2015. "Prediction of permeability anisotropy using Dar-Zarrouk parameters of deep resistivity logs: a case study in the northern Western Desert of Egypt." Arabian Journal of Geosciences 8, no. 12: 10497-10508.
Geoelectrical measurements were used in association with soil engineering tests in environmental engineering investigations at Tenth of Ramadan city, east Nile Delta, Egypt. The genetic algorithm (GA) approach with structure-based (SB) model is applied towards an optimal interpretation of DC resistivity measurements. The inverted models together with borehole data and soil classification exhibit two soil types, gravelly sand and clayey sand with free lime. The survey demonstrates that the combined use of the GA with SB model provides valuable information to constraint the number of interfaces. The reliable resistivity inversion results are considered as a key role in studying the geotechnical parameters such as Atterberg limits unconfined compressive strength and swelling tests. The clay sediments are described by medium plasticity and sensitivity for swelling. Further, the free lime with water makes gill action with decreasing the compressive strength. Therefore, such soil, in turn, may cause soil water appearance on the ground surface and geotechnical problems during or after the process of any construction. In this respect, the integration of the geoelectrical survey with soil engineering properties is efficient and less time consuming for characterizing the engineering-geologic zone.
Mohamed Attwa; Abdelaziz El Shinawi. Geoelectrical and Geotechnical Investigations at Tenth of Ramadan City, Egypt: A Structure-Based (SB) Model Application. Near Surface Geoscience 2014 - 20th European Meeting of Environmental and Engineering Geophysics 2014, 1 .
AMA StyleMohamed Attwa, Abdelaziz El Shinawi. Geoelectrical and Geotechnical Investigations at Tenth of Ramadan City, Egypt: A Structure-Based (SB) Model Application. Near Surface Geoscience 2014 - 20th European Meeting of Environmental and Engineering Geophysics. 2014; ():1.
Chicago/Turabian StyleMohamed Attwa; Abdelaziz El Shinawi. 2014. "Geoelectrical and Geotechnical Investigations at Tenth of Ramadan City, Egypt: A Structure-Based (SB) Model Application." Near Surface Geoscience 2014 - 20th European Meeting of Environmental and Engineering Geophysics , no. : 1.
Mohamed Attwa; Irfan Akca; Ahmet Tugrul Basokur; Thomas Günther. Structure-based geoelectrical models derived from genetic algorithms: A case study for hydrogeological investigations along Elbe River coastal area, Germany. Journal of Applied Geophysics 2014, 103, 57 -70.
AMA StyleMohamed Attwa, Irfan Akca, Ahmet Tugrul Basokur, Thomas Günther. Structure-based geoelectrical models derived from genetic algorithms: A case study for hydrogeological investigations along Elbe River coastal area, Germany. Journal of Applied Geophysics. 2014; 103 ():57-70.
Chicago/Turabian StyleMohamed Attwa; Irfan Akca; Ahmet Tugrul Basokur; Thomas Günther. 2014. "Structure-based geoelectrical models derived from genetic algorithms: A case study for hydrogeological investigations along Elbe River coastal area, Germany." Journal of Applied Geophysics 103, no. : 57-70.
Automated vertical electrical sounding (VES) inversion schemes were applied for hydrogeological characterisation at a semi-arid area in the southeastern part of the East Nile Delta, Egypt. The apparent resistivity measurements were integrated with borehole, hydrogeological and structural information for a better description of the subsurface conditions. The final results were presented in the form of cross-sections, maps and 3D diagrams to visualise the geological and hydrogeological situations. The resistivity values derived from the VES data were used to predict the hydraulic conductivity (K) values by using two empirical relations, which depend on the direct relation between K and the aquifer transverse resistance (T) and the power relation between K and the aquifer resistivity (ρ). The estimated values were compared with the observed K values obtained from the pumping tests. The power law relation produces more reliable predicted K values that show a good correlation with the data compiled for the hydraulic gradient of the main Pleistocene aquifer in the East Nile Delta. The results also indicate that the joint use of an automated 1D interpretation algorithm and the power law empirical relationship constitute a valuable tool to characterise the hydrogeophysical properties of aquifers in the study area. Des schémas d’inversion automatique de sondages électriques verticaux (SEV) ont été utilisés pour la caractérisation hydrogéologique dans une zone semi-aride dans la partie sud-orientale de l’Est du Delta du Nil en Egypte. Les mesures de résistivité apparentes ont été intégrées à l’information hydrogéologique et structurale ainsi que des forages pour obtenir une meilleure description des conditions du sous-sol. Les résultats finaux ont été présentés sous forme de profils, de cartes et de graphiques 3D afin de visualiser le contexte géologique et hydrogéologique. Les valeurs de résistivité obtenues à partir des données de SEV ont été utilisées pour prédire les valeurs de conductivité hydraulique (K) en utilisant deux relations empiriques, qui dépendent de la relation directe entre K et la résistance transverse de l’aquifère (T) et la relation de puissance entre K et la résistivité de l’aquifère (ρ). Les valeurs estimées ont été comparées aux valeurs observées de K obtenues à partir des essais de pompage. La loi de puissance produit une meilleure prédiction des valeurs K montrant une bonne corrélation avec les données compilées pour le gradient hydraulique de l’aquifère principal Pléistocène dans l’Est du Delta du Nil. Les résultats montrent également que l’utilisation conjointe d’un algorithme automatique 1D pour l’interprétation et une loi de puissance empirique constitue un outil de valeur pour caractériser les propriétés hydrogéophysiques des aquifères dans la zone d’étude. Se aplicaron los esquemas automatizados de inversión de los sondeos eléctricos verticales (VES) para la caracterización hidrogeológica en un area semiárida en la parte sudeste del Delta Oriental del Nilo, Egipto. La medidas de resistividad aparente fueron integradas con información de perforaciones, hidrogeológica y estructural para una mejor descripción de las condiciones del subsuelo. Los resultados finales se presentaron en forma de secciones transversales, mapas y diagramas 3D para visualizar las situaciones geológicas e hidrogeológicas. Los valores de resistividad derivados de los datos de los VES se usaron para predecir los valores de conductividad hidráulica (K) mediante el uso de dos relaciones empíricas, las cuales dependen de la relación directa entre K y la resistividad transversal del acuífero (T) y de la relación potencial entre K y la resistividad del acuífero (ρ). Los valores estimados se compararon con los valores observados de K obtenidos a partir de ensayos de bombeo. La relación de la ley potencial produce valores de K predichos más confiables que muestra una buena correlación con los datos compilados para el gradiente hidráulico del principal acuífero del Pleistoceno en el Delta Oriental del Nilo. Los resultados también indican que el uso conjunto de un algoritmo de interpretación automatizada 1D y la ley potencial de la relación empírica constituyen una herramienta valiosa para caracterizar las propiedades hidrogeofísicas de acuíferos en el área de estudio. 采用自动化的垂直电探测反向方案对埃及东尼罗河三角洲一个半干旱地区的水文地质特征进行了描述。视电阻率测量数据结合钻孔、水文地质和构造信息可以更好地描述地表以下的情况。最终结果以截面、地图和3D图的形式展示出来,使地质和水文地质状况可视化。通过采用两个经验关系并利用来源于垂直电探测电阻率值预测水力传导率值(K),这两个经验关系取决于K和含水层横向电阻率(T)的直接关系及K和含水层电阻率(p)的功率关系。对估算的值与抽水试验观测到的K值进行了对比。幂次定律关系可得到更加可靠的预测K值,显示与用于东尼罗河三角洲主要更新世含水层水利梯度编制资料有很好的关联性。结果还表明,联合应用自动化1D解译算法和幂次定律经验关系构成了描述研究区含水层水文地球物理特性的宝贵工具。 Foram aplicados esquemas automatizados de inversão de sondagens elétricas verticais (VES) para a caraterização hidrogeológica duma área semiárida, na parte sudeste do Delta Este do Nilo, no Egito. As medições de resistividade aparente foram integradas com informações de furos, dados hidrogeológicos e estruturais, para uma melhor descrição das condições sub-superficiais. Os resultados finais foram apresentados na forma de seções transversais, mapas e diagramas em 3D, para visualizar as situações geológicas e hidrogeológicas. Os valores de resistividade, derivados dos...
M. Attwa; Ahmet Tugrul Basokur; Irfan Akca. Hydraulic conductivity estimation using direct current (DC) sounding data: a case study in East Nile Delta, Egypt. Hydrogeology Journal 2014, 22, 1163 -1178.
AMA StyleM. Attwa, Ahmet Tugrul Basokur, Irfan Akca. Hydraulic conductivity estimation using direct current (DC) sounding data: a case study in East Nile Delta, Egypt. Hydrogeology Journal. 2014; 22 (5):1163-1178.
Chicago/Turabian StyleM. Attwa; Ahmet Tugrul Basokur; Irfan Akca. 2014. "Hydraulic conductivity estimation using direct current (DC) sounding data: a case study in East Nile Delta, Egypt." Hydrogeology Journal 22, no. 5: 1163-1178.
Field and laboratory spectral induced polarization (SIP) measurements are integrated to characterize the hydrogeological conditions at the Schillerslage test site in Germany. The phase images are capable of monitoring thin peat layers within the sandy aquifers. However, the field results show limitations of decreasing resolution with depth. In comparison with the field inversion results, the SIP laboratory measurements show a certain shift in SIP response due to different compaction and sorting of the samples. The SIP data are analyzed to derive an empirical relationship for predicting the hydraulic conductivity (K). In particular, two significant but weak correlations between individual real resistivities (ρ') and relaxation times (τ), based on a Debye decomposition (DD) model, with measured K are found for the upper groundwater aquifer. The maximum relaxation time (τmax) and logarithmically weighted average relaxation time (τlw) show a better relation with K values than the median value τ50. A combined power law relation between individual ρ' and τ with K is developed with an expression of A · (ρ')B · (τlw)C, where A, B and C are determined using a least-squares fit between the measured and predicted K. The suggested approach with the calculated coefficients of the first aquifer is applied for the second. Results show good correlation with the measured K indicating that the derived relationship is superior to single phase angle models as Börner or Slater models.
M. Attwa; T. Günther. Spectral induced polarization measurements for predicting the hydraulic conductivity in sandy aquifers. Hydrology and Earth System Sciences 2013, 17, 4079 -4094.
AMA StyleM. Attwa, T. Günther. Spectral induced polarization measurements for predicting the hydraulic conductivity in sandy aquifers. Hydrology and Earth System Sciences. 2013; 17 (10):4079-4094.
Chicago/Turabian StyleM. Attwa; T. Günther. 2013. "Spectral induced polarization measurements for predicting the hydraulic conductivity in sandy aquifers." Hydrology and Earth System Sciences 17, no. 10: 4079-4094.
Low-frequency field and laboratory induced polarization measurements are carried out to characterize the hydrogeological conditions at Schillerslage test site in Germany. The laboratory spectral induced polarization (SIP) data are analyzed to derive an empirical relationship for predicting the hydraulic conductivity (K) in the field scale. On the other hand, the results from SIP sounding and profiling field data indicate that the method identifies the lithological layers with sufficient resolution to achieve our objectives. Two main Quaternary groundwater aquifers separated by a till layer can be well differentiated. Furthermore, the phase images are also capable of monitoring thin peat layers within the sandy groundwater aquifer. However, the field results show limitations of decreasing resolution with depth and/or low data coverage. Similarly, the SIP laboratory results show a certain shift in SIP response due to different compaction and sorting of the samples. The overall results obtained show that the integration of field and laboratory SIP measurements is an efficient tool to avoid a hydrogeological misinterpretation. In particular, two significant but weak correlations between individual real resistivities (ρ') and relaxation times (τ), based on a Debye decomposition (DD) model, with measured K are found for the upper groundwater aquifer. While the maximum relaxation time (τmax) and logarithmically weighted average relaxation time (τlw) show a better relation with K values than the median value τ50, however, the single relationships are weak. A combined power law relation between individual ρ' and/or τ with K is developed with an expression of A · (ρ')B · (τlw)C, where A, B and C are determined using a least-squares fit between the measured and predicted K. The suggested approach with the calculated coefficients of the first aquifer is applied for the second one. The results indicate a good correlation with the measured K and prove to be superior to single phase angle models as the Börner or Slater models.
M. Attwa; T. Günther. Spectral induced polarization measurements for environmental purposes and predicting the hydraulic conductivity in sandy aquifers. Hydrology and Earth System Sciences Discussions 2013, 17, 4079 -4094.
AMA StyleM. Attwa, T. Günther. Spectral induced polarization measurements for environmental purposes and predicting the hydraulic conductivity in sandy aquifers. Hydrology and Earth System Sciences Discussions. 2013; 17 (10):4079-4094.
Chicago/Turabian StyleM. Attwa; T. Günther. 2013. "Spectral induced polarization measurements for environmental purposes and predicting the hydraulic conductivity in sandy aquifers." Hydrology and Earth System Sciences Discussions 17, no. 10: 4079-4094.
Due to the continuous increase in population, successive governments in Egypt have encouraged agricultural expansion and establishment of new communities in the desert fringes of the Nile Delta. The great challenge is to develop and assess the groundwater resources in such desert areas. The overall goal of this paper is to assess the hydrogeoligcal conditions at the Cairo-Bilbeis district area and its surrounding region, considered as semi-arid area in the southeastern part of Nile delta, Egypt. Forty-eight electrical soundings using Schlumberger array were carried out to configure the subsurface layer distributions. The sounding data were inverted and constrained by available geological information. Resistivity data were visualized as cross-sections and maps. The 1D inversion results emphasizes that the Quaternary deposits constitute the main groundwater aquifer in the northern part of the study area. In the southern parts, the aquifer represents by Tertiary sand. The established relationships between aquifer characteristics and electrical parameters have been used to estimate the hydraulic conductivity values of all the sounding locations including areas where no boreholes were non-existent. The present results can be utilized in predicting hydrogeological setting in future using groundwater modeling. In addition, the relationship between land reclamation and hydrogeological conditions can be anticipated.
M. Attwa. On the Use of DC Resistivity Soundings for Characterizing the Hydrogeological Conditions in Semi-arid Region- the East of Nile Delta, Egypt. Near Surface Geoscience 2012 – 18th European Meeting of Environmental and Engineering Geophysics 2012, 1 .
AMA StyleM. Attwa. On the Use of DC Resistivity Soundings for Characterizing the Hydrogeological Conditions in Semi-arid Region- the East of Nile Delta, Egypt. Near Surface Geoscience 2012 – 18th European Meeting of Environmental and Engineering Geophysics. 2012; ():1.
Chicago/Turabian StyleM. Attwa. 2012. "On the Use of DC Resistivity Soundings for Characterizing the Hydrogeological Conditions in Semi-arid Region- the East of Nile Delta, Egypt." Near Surface Geoscience 2012 – 18th European Meeting of Environmental and Engineering Geophysics , no. : 1.
Mohamed Attwa; Thomas Günther; Michael Grinat; Franz Binot. Evaluation of DC, FDEM and IP resistivity methods for imaging perched saltwater and a shallow channel within coastal tidal flat sediments. Journal of Applied Geophysics 2011, 75, 656 -670.
AMA StyleMohamed Attwa, Thomas Günther, Michael Grinat, Franz Binot. Evaluation of DC, FDEM and IP resistivity methods for imaging perched saltwater and a shallow channel within coastal tidal flat sediments. Journal of Applied Geophysics. 2011; 75 (4):656-670.
Chicago/Turabian StyleMohamed Attwa; Thomas Günther; Michael Grinat; Franz Binot. 2011. "Evaluation of DC, FDEM and IP resistivity methods for imaging perched saltwater and a shallow channel within coastal tidal flat sediments." Journal of Applied Geophysics 75, no. 4: 656-670.