Mahmoud Mekkawi - Academia.edu (original) (raw)

Papers by Mahmoud Mekkawi

NRIAG Journal of Astronomy and Geophysics, 13:1, 75-90,, 2024

Magnetic resonance sounding (MRS) was performed to evaluate its applicability for characterising ... more Magnetic resonance sounding (MRS) was performed to evaluate its applicability for characterising groundwater at selected locations in Aswan Governorate, Egypt. The MRS mainly detects a weak but noticeable alternating magnetic field as MRS signals when the proton spin in groundwater produces non-magnetic moments and rotates around the geomagnetic field, indicating the detection of groundwater. The MRS system was first correlated at a piezometer with a known water table depth (~80 m). Subsequently, three MRS sounding stations with unknown water tables were tested at Qism Aswan at ~ 18 km from the piezometer using NUMIS Auto magnetic resonance sounding system following the MRS site common practices. The MRS data were subjected to adaptive notch filtering to remove spiky noise and potential power line harmonics, and finally enhance the MRS signals at the selected stations. The water depth (~75-95 m) estimated from the MRS data around the piezometer largely coincides with the actual depth (~80 m) at the piezometer itself. A transient electromagnetic (TEM) profile performed near the measured MRS stations indicates no water content. Unlike the MRS data for NNL-1, the data for NNL-2 and NNL-3 match well with TEM data at shallow depths. The evaluation generally indicates that the MRS method is applicable for groundwater exploration at the selected piezometer and the other three stations. However, the method necessarily requires additional denoising efforts to comprehensively characterise groundwater occurrence and aquifer parameters.

journal of Applied Science, 2023

Many different countries use geophysical technologies in their archaeological research. In the st... more Many different countries use geophysical technologies in their archaeological research. In the study area (Menofia, Egypt), we employed magnetic and ground-penetrating radar techniques. In the southern part of Egypt's northern Delta, between the Nile Rashid and Damietta branches, is the Menofia Governorate. Tal-El Bendariya was chosen as the study location since the majority of its activity ended during the Roman era. For the magnetic survey, Tal-El Bendariya was separated into three locations (sites), and one suitable site was chosen for the GPR study. Using Geoplot, Reflexw, and Surfer software, the magnetic data and GPR data were corrected processed, and interpreted to produce images that depicted the underground artifacts that were present in the area. The magnetic data at Tal-El Bendariya revealed a significant number of anomalies with a variety of unusual geometric patterns. They are interpreted to be the location of historical hearths and kilns made of firebricks as well as fragments of ancient walls made of fire and mud bricks. The findings from the GPR data, meanwhile, point to a few scattered parts of mud brick walls. It was established that the research region at Tal-El Bendariya might have been an area of an ancient pottery industry during the Roman era after integrating the magnetic and GPR results.

Arabian Journal of Geosciences, 2023

In the Wadi Qena region, the digital elevation model (DEM), aeromagnetic, and magnetotelluric dat... more In the Wadi Qena region, the digital elevation model (DEM), aeromagnetic, and magnetotelluric data are processed and examined to outline surface water flow patterns, the subsurface structures, demonstrate their effects on the groundwater flow direction, and assess the groundwater aquifer thickness and the relationship between subsurface structures and the inherited surface water flow (drainage pattern). Wadi Qena's drainage pattern and watershed basins were delineated using satellite digital elevation data in order to accomplish these objectives. The first vertical derivative transformation was used and examined to determine the prevailing northwest-southeast and northeast-southwest structural trends impacting the region. In order to handle aeromagnetic data, it is necessary first to reduce the observed magnetic data such that they correspond to the reduced magnetic pole (RTP). The two-dimensional analytical signal technique was used to discover that the depth of the basement rocks, which in the research region serve as the bedrock of the overlying groundwater aquifer, ranges from 101 to − 1165 m relative to sea level. This information was obtained by measuring the distance from the earth's surface to the bedrock. To further define the accurate subsurface geological model in the region, the conducted magnetotelluric survey in the area was interpreted using the 1-D inversion technique, and the results were coupled with the existing drill data. The base of the groundwater aquifer was discovered to be between 350 and 410 m deep. Finally, the results are reliable and closely related to earlier geological and geophysical investigations in the studied area.

Pure and Applied Geophysics, 2023

Magnetic methods of exploration have proved to be efficient and have potential in the gold minera... more Magnetic methods of exploration have proved to be efficient and have potential in the gold mineralization industry. New magnetic processing technologies aid in improving the process of interpretation and gold opportunity identification. In this work, we show the possible application of combined digital magnetic filters to explore new gold mineralization localities with application to a well-known Au mineralization zone. Um Garayat (UG) region, southeastern desert, Egypt, is an ancient example of a potential area for gold mining. Modern analysis showed that other types of mineral concentrations are present. So, exploiting the magnetic signature of the area for future investment is of great interest. The old UG gold mine is characterized by volcanic and tectonic features such as faulting and folding that affect the arc sedimentary rock sequence of repeated deformation stages. A thorough geophysical effort has been carried out around the old gold mine in the UG area to explore the exte...

NRIAG Journal of Astronomy and Geophysics

Reducing expenses is a critical aspect of natural resource explorations, especially in the reconn... more Reducing expenses is a critical aspect of natural resource explorations, especially in the reconnaissance stage. Accordingly, GIS algorithms using the free remote sensing data were used to rank the probable mineralised zones before any future implementations of the highcost drilling and/or detailed geophysical programmes. Geological and tectonic settings, and being a historical mineral resource were motivations to choose the Allaqi-Heiani Suture (AHS), Upper Egypt, as a study area. Remote sensing data were processed for tracing the probably mineralised alteration zones, determining fractures and dominating structural systems, and mapping different geological units. Various alteration minerals including hydroxyls-carbonates, ferrous and ferric iron oxides were detected over different rock units using band ratio (BR) and Crosta techniques. Different geological units were distinguished using false colour composite (FCC) images. Moreover, an intense fractured system, demonstrating the area, was revealed by tracing lineaments using informative, spatially enhanced remote-sensed images. Fractures within the altered rocks represent 35% of the total fracturing system in the AHS to indicate a structural system controlling mineralisation occurrences. The processing of magnetic data suggested a deep/buried nature of these remotely detected lineaments/structures. Reduced to pole (RTP) and tilt derivative (TDR) maps detected the buried magnetic sources, whereas zero contours of TDR, Euler deconvolution, analytic signal and source parameter imaging (SPI) techniques traced buried contacts/structures and estimated their depths. A GIS strategy depending on the intensity of the fracturing system and the presence of more than one type of alteration was applied to potential-rank the prospective mineralised occurrences over AHS. The correlation between ranked zones with the old/known mines showed encouraging evaluation.

Geocarto International

Although the continuity of gold mining work since Pharaonic times till today, Wadi Haimur is stil... more Although the continuity of gold mining work since Pharaonic times till today, Wadi Haimur is still promised source for gold. Wadi Haimur is located in west Allaqi-Heinai-Suture (AHS), south Eastern Desert of Egypt. Gold mineralization is mainly confined within quartz-carbonate and sulphide-bearing quartz veins within sheared, altered rocks, while listvenitization plays a significant role in gold concentration along the Haimur area. Therefore, critical analyses of remote sensing data were applied to map alteration zones and delineate listvenites. Spatially enhanced images were processed to trace lineaments and weakness zones which may represent pathways of mineralized, ascended hydrothermal fluids. Ground geophysical, magnetic and geoelectric surveys were performed to study the depth-extension of mineralized bodies in the vicinity of the historical mines within Wadi Haimur. Interpretation of land-magnetic data indicates the presence of mineralized veins associated with narrow shear zones. Derivatives and highpass filters were utilized to map shallow mineralized sources and deduce their trends. Upward continuation and low-pass filters were used to detect the deep sources. Depths to magnetic bodies were estimated using Power-Spectrum, Euler and inversion of single anomalies. Geochemical sampling was performed to test the results. According to the remarkable variation in resistivity and chargeability values of resistivity and inducedpolarization tomography profiles, the subsurface lithology was classified and probable mineralized zones within the subsurface were detected. Encouraging results from regolith, trenching, rock-chip sampling and Reverse-Circulation (RC) drilling indicated the extension of auriferous anomalies within the bedrock. Good correlation of RC-holes auriferous anomalies depths and deduced depths from magnetic interpretation was revealed.

EGU General Assembly Conference Abstracts, Apr 1, 2019

EGU General Assembly Conference Abstracts, Apr 1, 2016

The study of seismic hazard assessment around greater Cairo-Egypt is very important due to conden... more The study of seismic hazard assessment around greater Cairo-Egypt is very important due to condense population (more than 20 million) in that area. Although, Egypt is characterized by low seismic activity. The seismotectonic zones and high activity are occurred along the Gulf of Aqaba–Dead Sea transform, the Northern Red Sea triple junction point, Aswan, Dahshur, and Cairo-Suez District. In this study, earthquake catalogue (up to 2015) of all seismo-tectonic zones in Egypt and its surroundings are used. Beside the seismicity analysis, gravity and magnetic maps of Dahshur area are analyses for tracing active subsurface faults that are responsible of earthquakes activity. The surface geology and subsurface faults are used to evaluate the tectonic framework in the area under study. Also, The seismicity maps, focal depths and seismic hazards values are calculated.

Journal of African Earth Sciences, 2022

Plateau. This region is adjacent to the Gulf of Suez rift, which is an active geothermal area, as... more Plateau. This region is adjacent to the Gulf of Suez rift, which is an active geothermal area, as indicated by the geothermal surface manifestations, such as thermal hot springs. It is a zone between two tectonic plates, which is expected to have several geothermal reservoirs; consequently, it represents a potential area for geothermal prospecting. Aeromagnetic data interpretation was performed to define the deep and shallow structures in the study area and their distribution to select a suitable site and perform more detailed prospection. Consequently, two sites were chosen to conduct a detailed study, with land magnetic and (1D MT) to discover variations in conductivity (resistivity) and fix the depth of predicted geothermal reservoir as well as the distribution of deep and shallow faults which can facilitate geothermal solutions flow and injection to exploit the geothermal source energy. The obtained results showed that the study area is intensely faulted with major NW-SE trend and minor E-W trend. Meanwhile, the (MT) results show several conductive and resistive zones at different depths, which could be correlated with faulting zones, suitable to predict geothermal sources and aquifers.

The Egyptian Journal of Remote Sensing and Space Science, 2022

Wadi-Allaqi district, in the southern part of the Eastern Desert of Egypt, is a historic well-kno... more Wadi-Allaqi district, in the southern part of the Eastern Desert of Egypt, is a historic well-known gold resource that has been exploited since the Pharaonic era. The study area represents the western segment of Wadi-Allaqi, about 220 km southeast Aswan city, Upper Egypt. It covers approximately 4702 km 2. Exploring new potential mineralization zones was conducted by integrating the Landsat-8 and aeromagnetic data to map different surfaces of alteration zones and trace shallow and deep mineralized bodies. The corrected Landsat-Operational Land Imager (OLI) bands were processed using the Band Ratio (BR), Crosta, selective for the Minimum Noise Fraction (MNF) transformation, and False-Color Composition (FCC) techniques were used to detect the hydrothermal alteration zones and recognize the different geological units. The enhanced eigenimage (MNF1) was processed to delineate the fractures and weakness zones over the west Allaqi-Heini Suture (AHS). The shallow residual mineralized sources have been detected and mapped using the Tilt Derivative (TDR), First Derivative (FVD) and high pass filter techniques of aeromagnetic data. The depths to the mineralized magnetic sources, and hence the roots of gold and other minerals, were obtained using the power spectrum and Euler techniques. Accordingly, new gold and mineralization potential zones were successfully delineated over the study area's ophiolitic, metavolcanics, and granitic rocks. Lineaments deduced from aeromagnetic and remote sensing data represent the pathways of the ascending hydrothermal fluids. The main trends of the dominant structural systems were detected through the statistical analyses of these lineaments.

An intensity study has been performed for Hot Spring, central Sinai, in order to illustrate the r... more An intensity study has been performed for Hot Spring, central Sinai, in order to illustrate the role of magnetotelluric (MT) and magnetic interpretation in the detection of majorsubsurface tectonic structural elements affecting both the sedimentary section and the underlying basement complex. More attention was given to the Hot Spring to spot more light on the subsurface structural features, which control the behavior of this spring. For thexecution of this investigation, MT measurements carried out with about 10 km distance, in which the Hot Spring is located at the middle of their profiles. According to the results of 1D numerical model, the area is tectonically active and there is a conductive anomaly situated just beneath the hot spring at a depth of 2.2 km. The modeling revealed that, a possible connection between this anomaly and the conductive sediments, which can be considered as the source of the phenomena.

Advances in Science, Technology & Innovation, 2019

Advances in Science, Technology & Innovation (ASTI) is a series of peer-reviewed books based on t... more Advances in Science, Technology & Innovation (ASTI) is a series of peer-reviewed books based on the best studies on emerging research that redefines existing disciplinary boundaries in science, technology and innovation (STI) in order to develop integrated concepts for sustainable development. The series is mainly based on the best research papers from various IEREK and other international conferences, and is intended to promote the creation and development of viable solutions for a sustainable future and a positive societal transformation with the help of integrated and innovative science-based approaches. Offering interdisciplinary coverage, the series presents innovative approaches and highlights how they can best support both the economic and sustainable development for the welfare of all societies. In particular, the series includes conceptual and empirical contributions from different interrelated fields of science, technology and innovation that focus on providing practical solutions to ensure food, water and energy security. It also presents new case studies offering concrete examples of how to resolve sustainable urbanization and environmental issues. The series is addressed to professionals in research and teaching, consultancies and industry, and government and international organizations. Published in collaboration with IEREK, the ASTI series will acquaint readers with essential new studies in STI for sustainable development.

NRIAG Journal of Astronomy and Geophysics, 2013

Dahshour area has recently shown a great potential of archeological findings. This was remarkable... more Dahshour area has recently shown a great potential of archeological findings. This was remarkable from the latest discovery of the causeway and the mortuary temple of the Pyramid of Amenemhat III using geophysical data. The main objective of the present work is to locate the buried archeological remains in the area of Dahshour, Southwest Cairo using magnetic survey for shallow investigations. Land magnetic data is acquired using proton magnetometer (two sensors) with a sensor separation of 0.8 m; i.e. gradiometer survey. The study area is located nearby the two known pyramids of Dahshour. The field data is processed and analyzed using Oasis Montaj Geosoftä software. The processed data is presented in order to delineate the hidden artifacts causing the magnetic anomalies. The results indicated a distribution of the buried archeological features within the study area. These archeological features are detected according to the magnetic contrast between the magnetic archeological sources (such as mud bricks, basalt and granite) and the surroundings; mainly sandy soil. The delineated archeological features at Dahshour are probably dated back to the old kingdom having a depth reach up to 3.0 m. Consequently it is highly recommended to carry out excavation to precisely classify them and high light their nature and value.

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Abstract: The south Zagros Suture Zone (ZSZ) is located in Northern Eastern part of Kurdistan reg... more Abstract: The south Zagros Suture Zone (ZSZ) is located in Northern Eastern part of Kurdistan region-Iraq and is known as volcano-tectonic area. It is characterized by its potential iron resources. In this study, we attempt to delineate the subsurface structures ...

International Journal of Gynecology & Obstetrics, 2000

Journal of Geology & Geophysics, 2017

The Geologic and Tectonic Setting The Western Desert of Egypt covers an area more than 600,000 km... more The Geologic and Tectonic Setting The Western Desert of Egypt covers an area more than 600,000 km 2 and comprises almost two thirds of the whole area of Egypt. The North Western Desert represents an important part of the unstable shelf of Northern Africa. It has been subjected to different tectonic regimes since the Paleozoic time, which were able to form the construction of many basins, sub-basins, ridges, troughs and platforms. The West Qarun concession is located to in the north part of the Western Desert (Figure 1). It is close to the Nile Delta region and the convergence boundary of three plates (Euroasian, Africa and Arabian). Also, it is affected by the opening of the Red Sea and its branches (Gulf of Suez and Gulf of Aqaba). Thus the seismic activity there is due to the interaction between the three plates. These structural features encourage foreign companies to establish condensed exploration works in this region. The Western

Arabian Journal of Geosciences, Apr 1, 2021

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.

Si la plupart des séismes sont dus à la dérive des continents1, certains d'entre eux peuvent... more Si la plupart des séismes sont dus à la dérive des continents1, certains d'entre eux peuvent être pro-voqués par les activités industrielles de l'Homme. C'est notamment le cas dans la région du lac Nasser (Egypte), où l'on a pu montrer, à partir du catalogue sismique de la zone et ...

Due to the big consuming of ground water in agricultural activities, the reservoir water of Kharg... more Due to the big consuming of ground water in agricultural activities, the reservoir water of Kharga Oasis is noticeably decreased. The demand of drilling deeper wells is increased and most of them reached to the basement rocks. The well data have been observed since 40 years. Over-exploitation of reservoir systems has caused a decline in water table in many parts in the area under studied between 60-80 m. Hot springs are found in the southern part of Kharga City of water temperature 45° C. Magnetotelluric (MT) measurements are carried out in the northern part of Kharga oasis, in order to image the deep part of its reservoir water, using available data of hydro-geology and boreholes information. The results of MT analysis in 1D and 2D show that the sediments of Quaternary and Paleocene (less than 1 km.) have low resistivity value, while the high resistivity value belongs to the basement complex of Pre-Cambrian rocks at depths greater than 1 km. Keywords: Kharga Oasis Reservoir water (KOR), hydro-geology and magnetotellurics

NRIAG Journal of Astronomy and Geophysics, 13:1, 75-90,, 2024

journal of Applied Science, 2023

Arabian Journal of Geosciences, 2023

Pure and Applied Geophysics, 2023

NRIAG Journal of Astronomy and Geophysics

Geocarto International

EGU General Assembly Conference Abstracts, Apr 1, 2019

EGU General Assembly Conference Abstracts, Apr 1, 2016

Journal of African Earth Sciences, 2022

The Egyptian Journal of Remote Sensing and Space Science, 2022

Advances in Science, Technology & Innovation, 2019

NRIAG Journal of Astronomy and Geophysics, 2013

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International Journal of Gynecology & Obstetrics, 2000

Journal of Geology & Geophysics, 2017

Arabian Journal of Geosciences, Apr 1, 2021

SSG-Saudi, 2020

The iron deposits are widespread in the eastern and western provinces of Aswan. The ironstone dep... more The iron deposits are widespread in the eastern and western provinces of Aswan. The ironstone deposits of the East Aswan are of bedded oolitic type and occur in the form of two bands inter-bedded with ferruginous sandstone and clay capping Precambrian rocks. The thickness of the bands varies from 0.5 to 3.5 meters. It was strongly influenced by multiple stage of deformation resulting in folding and faulting.
The iron-bearing minerals of the East-Aswan deposits are mainly hematite, chamosite, goethite, and other constituents like pyrite and siderite (Mücke, 2000). In order to evaluate the iron ore deposits in Um Barmil area, land magnetic survey and geochemical analyses to cover all iron ore locations. The magnetic profiles have conducted on such area, where iron ore deposits are concentrated. Rock samples are collected for chemical analysis. The X-Ray Fluoresce (XRF) and X-Ray Diffraction (XRD) techniques are applied for Iron concentration (Fe %) and other minerals contents in the rock samples at Um Barmil area.
The area is dissected by major faults striking in the NW-SE and NE-SW directions. The most interesting results are the location of the mineralization zone as well correlated with the locations of the contacts/faults deduced from high pass filter, horizontal gradient, analytical signal and tilt derivative methods. This indicates that the iron ore deposits locations at East-Aswan area are structurally controlled especially in the shallower part. The results of rock samples and cores analysis showed that the iron ore deposits are concentrated in the Um Barmil area with mean ratio reach to 42.30 %. Also, there are good agreements between magnetic interpretation, iron ore deposits occurrences and geochemical results.

SSG-2020, 2020

The gold mines are located in the south Eastern Desert, Egypt, about 180 km far from Aswan city a... more The gold mines are located in the south Eastern Desert, Egypt, about 180 km far from Aswan city and are known as volcano-tectonic area. A number of important ancient gold mines in the area have, however, received relatively little geological and geophysical attentions. Several mines occurrences (El-Haimur, Um El-Garayat, Nile Velley concessions and Kolt Um El-Garayat) are confined to E-W fold and thrust belts stacked ophiolitic slices, NW-vergent folding and thrusting, with concomitant magmatic activity.
The magnetic measurements are carried out along the old mines where the gold ores of Haimur and Um Garayat are concentered in quartz veins. Several geoelectrical (ER) profiles were measurements by using dipole-dipole configuration of electrode spacing 5, 10 and 15 m of lengths ranging from 160-240 m. In additional to more than ninety (TEM) time domain electromagnetic soundings are applied. The results indicate that the gold ore deposits are accomplished with sulfide zones which refer to low resistive zones, high chargeability with moderate to high magnetic anomalies.

Key words: South Eastern Desert, Alter mineralized zone, Land magnetic, Electrical and Electromagnetic methods.