Abotalib Z. Abotalib

University of Southern California | USC · School of Engineering

Paleoclimatic regimes over Saharan Africa alternated between dry and wet periods throughout the Pleistocene Epoch, and it is during the wet periods that the Saharan fossil aquifers were recharged. We investigated the role of groundwater-related processes in shaping the Saharan landforms (e.g., theater-headed valleys [THV]; depressions , escarpments...

Chronological and geochemical data from scarp and scarp-foot depression sediments (SSDS) have been used for deciphering Saharan paleoclimates and patterns of migration of anatomically modern humans (AMH). U-Th dating of thick accumulations of SSDS indicates prevalent deposition during long-lasting cool glacial periods (marine isotope stage [MIS] 6,...

Eastern Arabian Peninsula represents the main natural groundwater discharge area of the Arabian platform fossil aquifer system. In such settings, connections between aquifers could strongly affect the flow dynamics, water quality and availability as well as karst formation and landscape evolution. Geological structures such as folds and faults are...

The recurring slope lineae on Mars have been hypothesized to originate from snow melting, deliquescence, dry flow or shallow groundwater. Except for the dry flow origin, these hypotheses imply the presence of surficial or near-surface volatiles, placing the exploration and characterization of potential habitable environments within the reach of exi...

Shallow aquifer mapping and large-scale characterization of groundwater dynamics in the Saharan-Arabian desert is largely impeded by the limited hydrological datasets from sparse and unevenly distributed well logs. Today, as these aquifers are depleting at alarming rates in response to climatic and anthropogenic stresses, accurate knowledge of thei...

Egypt observes one of the highest water budget deficits in Africa that is mainly compensated by intensive reuse of untreated agricultural drainage water in the Nile Delta. The implications of untreated water reuse on increasing soil pollution levels remain poorly characterized; however, a large-scale pollution can compromise crop production and wat...

The past decade witnessed the initiation and boom of the Artisanal and Small-scale Gold Mining (ASGM) activities in the hyper-arid southern Egypt. The ores are mined in the Eastern Desert and then transported to the densely populated farming communities in the Nile Valley, where the river provides the water resources needed for ore processing. In s...

Waterways’ regeneration is proposed as one of the main mitigation strategies for addressing the alarming water budget deficit in the populous, hyper-arid Egypt, relying primarily on the Nile as its most important water source. The latter is increasingly under pressure from a rise in internal consumption, droughts, and upstream damming. We perform h...

The present study addresses the origin and evolution of the mega-scale topographic depressions (area: up to 45,000 km2) in the hyperarid Sahara Desert using integrated field, remote sensing, structural, and geochemical observations acquired over the plateau bounding the Farafra Oasis from the east. The plateau (height: 300 m) is formed mainly of ka...

We thank Wheeler et al for positively confirming our results’ reproducibility; however, we show herein that their critique misrepresents the aim, approach, and interpretations reported in Heggy et al (2021 Environ. Res. Lett. 16 074022), which remain valid. The reply herein demonstrates that Wheeler et al incorrectly interpreted Heggy et al ’s (202...

Using Health personal protective equipment (PPE) such as face masks, safety foot shoes and protective suits has expanded dramatically due to COVID-19 pandemic leading to a widespread distribution of the PPE, particularly the face masks, in the environments including streets, dump sites, seashores and other risky locations. The environmental degrada...

Using Health personal protective equipment (PPE) such as face masks, safety foot shoes and protective suits has expanded dramatically due to COVID-19 pandemic leading to a widespread distribution of the PPE, particularly the face masks, in the environments including streets, dump sites, seashores and other risky locations. The environmental degrada...

The focus of this study is to locate shallow groundwater (SGW) occurrences in arid lands using the Western Desert (WD; area: ∼680,000 km²) of Egypt as a test site. The SGW in the study area originated from paleo-precipitation during previous wet climatic periods. In wet periods, fossil groundwater was at higher levels, ascended along high-angle fau...

The reply herein shows the factual incorrectness of the comment by Eladawy, Asefa and El Nour, which is primarily supported by miscitations and misinterpretations of published research, as well as by claims from social media and unreliable TV interviews. The comment mistakenly omit the different components of the calculated total water budget defic...

Mega-streamlined landforms on Earth and Mars have been attributed to aeolian, glaciogenic, fluvial, and tectonic processes. Identifying the forces that shaped these landforms is paramount for understanding landscape evolution and constraining paleo-climate models and ice sheet reconstructions. In Arabia, east-northeast trending, kilometer-scale str...

More extreme and prolonged floods and droughts, commonly attributed to global warming, are affecting the livelihood of major sectors of the world's population in many basins worldwide. While these events could introduce devastating socioeconomic impacts, highly engineered systems are better prepared for modulating these extreme climatic variabiliti...

Mass gathering events commonly encounter environmental challenges that necessitate assurance of water quality and food security. The current outbreak of the coronavirus disease 2019 (COVID-19) call for maintaining safe drinking water supply and providing assessment tools of drinking water quality to avoid contamination in water sources or distribut...

The absence of large archaeological settlements in the Eastern Arabian Peninsula suggests that most of the recent wet periods occurring during climate oscillations in these areas were short-lived. However, a ~ 2-by-3-km buried rectangular feature was discovered opportunistically in the southeast of the Qatar Peninsula while performing radar subsurf...

During the last decade, the desert fringes of the Nile Valley in Egypt witnessed a vast expansion of groundwater-fed reclaimed lands. However, waterlogging and drainage-induced groundwater quality issues started to be of concern in many locations in these developed areas. In this study, an integrated methodology (landscape analysis , electric geoph...

The Nile River is a unique environmental system and essential water resource for its basin riparian nations. Population growth, changes in precipitation patterns, damming and usage rights disputes present extreme challenges in utilizing and managing the basin’s primary water resource. These stress factors are of particular concern for highly popula...

Digital elevation models (DEMs) are the cornerstone for hydrological and geomorphological modeling. Herein, two Nile-tributary catchments (Wadi Al Rishrash and Wadi Atfeh) in Egypt are selected to examine the contribution of different DEMs to the accuracy of hydrological and geomorphological analyses in the hyper-arid Sahara. DEMs sources include:...

Mega-streamlined landforms on Earth and Mars have been attributed to aeolian, glaciogenic, fluvial, and tectonic processes. Identifying the forces that shaped these landforms is paramount for understanding landscape evolution and constraining paleo-climate models and ice sheet reconstructions. In Arabia, east-northeast, kilometer-scale streamlined...

Contemporary cities continue to face significant geoenvironmental challenges due to constant rapid urbanization. Furthermore, the governments of cities worldwide are considering the green cities approach to convert their cities’ weaknesses into opportunities. The 2030 Saudi vision supports smart growth concepts, with a vision of speeding up economi...

Satellite gravity missions represent an important contemporary source of data for both hydrological and oceanic studies. The present study assesses the seasonal variability of Mediterranean Sea level using temporal observations from the Gravity Recovery and Climate Experiment (GRACE) mission. The GSM and GAD solutions from the German Research Centr...

The role of faults in controlling groundwater flow in the Sahara and most of the hyper‐arid deserts is poorly understood due to scarcity of hydrological data. The Wadi Araba Basin (WAB), in the Eastern Sahara, is highly affected by folds and faults associated with Senonian tectonics and Paleogene rifting. Using the WAB as a test site, satellite ima...

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 s...

The impact of land cover/land use (LCLU) changes on surface runoff and groundwater contamination have been widely investigated, yet their impact on groundwater mixing is still poorly understood. The stress on resources in the Nile Delta triggered a vast migration of urban, agricultural, and industrial activities to its desert fringes exposing the Q...

The rapid increase in the population of many of the older major cities within the countries of the Saharan-Arabian Desert is steering vast and disorganized urban expansion and in many cases introducing adverse environmental impacts such as soil erosion, rise in groundwater levels, and contamination of shallow aquifers, as well as development of def...

Mega-streamlined landforms (MSL) can be attributed to multiple erosional processes. Identifying the forces that shape these landforms could advance our understanding of the earth’s paleoclimate, constrain ice sheet reconstructions, and assist in interpreting extraterrestrial analogues. Field and satellite-based observations support a Late Ordovicia...

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 mitig...

Global warming and anticipated increase of rainfall frequency and magnitude are linked to enhanced rockfall activity worldwide. Arid environments, which currently receive limited amount of annual rainfall, will be particularly subject to frequent and unpredictable rockfall activity that can substantially jeopardize human lives and infrastructures....

Lake-aquifer interactions have been the subject of investigation and debate for decades. Traditional investigation methods include measurement of water flux across the groundwater–surface water interface, application of heat and environmental tracer methods, conducting numerical simulations of the water flow, and mass balance–based approaches. We f...

Water resources in the Nile Delta have been subjected to ongoing deterioration in quality and quantity as a result of decreasing Nile water flux, poorly managed groundwater abstraction and anthropogenic activities along the course of the Nile branches and drainage canals. Therefore, a proper assessment of water quality is essential to determine the...

Even though assessment of aquifer characterization and recharge mechanisms in rift-related basins, especially in arid environments, is essential for developing sustainable management strategies and food security assurance, a little attention has been paid to understand these parameters. In this manuscript, we utilize an integrated remote sensing, h...

The Nile Delta is home to half of Egypt's population and has ample agricultural, industrial, and cultural resources, yet the land subsides in response to many natural and anthropogenic impacts. We report the recent subsidence rate and patterns in the Nile Delta using the synthetic aperture radar Sentinel-1 data of 144 images obtained between 2015...

Reduction of the formation fluid pressure in response to oil and gas abstraction and the consequence reservoir compaction and the movement of the overburden result in prominent surface ground deformation. In this study, we use Interferometric Synthetic Aperture Radar (InSAR) for measuring the ground deformation over mega oil fields in Kuwait, where...

In this study, we delineate the distribution of ENE-oriented mega-linear features in NW Saudi Arabia and investigate their origin using observations extracted from satellite images (e.g. ALOS PALSAR, Landsat, and SRTM) geologic maps, and field observations. These features extend, north of latitude 24°N, over the peneplained Neoproterozoic Arabian S...

Exhumed Paleozoic glacial deposits and landforms of the North Gondwana are reported here for the first time from the South Eastern Desert (SED) of Egypt. Using field observations and remote sensing datasets (Advanced Land Observing Satellite [ALOS], Phased Array L-band Synthetic Aperture Radar [PALSAR] radar, multispectral Landsat TM datasets, and...

Natural and human-induced groundwater dynamics in hyper-arid aquifers play a crucial role in the evolution of the landscape. The area overlying the Saq Aquifer, in particular the Al-Qassim area within the central part of the Kingdom of Saudi Arabia, has witnessed numerous land deformation (land subsidence and issures) events throughout the last two...

There is a general agreement that deep aquifers experience significant lag time in their response to climatic variations. Analysis of Temporal Gravity Recovery and Climate Experiment (GRACE), Soil Moisture and Ocean Salinity mission (SMOS), satellite altimetry, stable isotopic composition of groundwater, and precipitation and static global geopoten...

Sand sheets and barchan dunes are a dominant landscape feature of the hyper-arid deserts of North Africa and the Arabian Peninsula. The ability to characterize their morphology, moisture content, internal layering and structure provides unique insights into both the local and regional paleoclimatic conditions that prevailed during their formation a...

Understanding the role of geological structures in controlling groundwater flow in fossil aquifers is central for proper assessment of groundwater dynamics and aquifer connections. In such settings, connections between deep and shallow aquifers could potentially affect groundwater quality and availability as well as karst formation and landscape ev...

Groundwater mounding is the localized rise of groundwater table against the regional hydraulic gradient, when a focused recharge rate to an aquifer exceeds the rate at which water is conveyed away from the recharge zone. Groundwater mounds (GM) commonly occur in shallow aquifers under humid conditions by the infiltrating storm water through high co...

Understanding the mechanism of formation of fluvial landforms on Mars, is essential for a proper assessment of its paleoclimatic and current hydrologic conditions. The origin of Martian theater-headed valleys (THV) has long been a subject of debate with several hypotheses including groundwater sapping, mega-flooding, lava flows, and landslides. We...

The nature and timing of Saharan wet periods were attributed to the intensification of paleo-monsoons during interglacial periods or intensification of paleo-westerlies in glacial periods. Regardless of whether the wet periods were glacial or interglacial in origin, the excessive precipitation during these periods led to considerable rise of ground...

Wadi Qena basin represents one of the most promising regions for future development in Egypt. Fresh water supplies are crucial for such plans. We provide an integrated remote sensing (Landsat, ASTER DEM, Geoeye-1), geophysical (aeromagnetic), isotopic (δ18O, δ2H), field (stratigraphic and structural interpretation) and geochemical (major dissolved...

We developed and successfully applied data-driven models that heavily rely on readily available remote sensing datasets to investigate probabilities of algal bloom occurrences in Kuwait Bay. An artificial neural network (ANN) model, a multivariate regression (MR) model, and a spatiotemporal hybrid model were constructed, optimized, and validated. T...

Paleoclimatic regimes over Saharan Africa alternated between dry and wet periods throughout the Pleistocene Epoch, and it is during the wet periods that the Saharan fossil aquifers were recharged. We investigated the role of groundwater-related processes in shaping the Saharan landforms (e.g., theater-headed valleys [THV]; depressions, escarpments,...

The wet climatic periods in the Quaternary in north Africa and in Arabia were traditionally attributed to intensification of paleo-monsoons during interglacial periods and progressive northward migration of monsoonal front. In N Africa, the monsoonal model could not account for: (1) progressive W to E depletion (Morocco: -20 to -40‰; ; Libya: -70 t...

There is considerable debate on the origin, age, and paleoclimatic setting of Late Quaternary deposits within the basement complex of the Sinai Peninsula. Our research in Wadi Feiran focused on documenting the sedimentology, stratigraphy, geochemistry and chronology of Late Quaternary deposits in the Feiran (lat. 28.706 N; long. 33.665; elevation:...

Structural control on the groundwater flow in arid regions is still poorly understood. Understanding the distribution of structural discontinuities (i.e. faults, joints and shear zones), their cross cutting relationships, and their relation with the regional hydraulic gradient are critical for deciphering the complexity of water resources distribut...

Wadi Qena basin represents one of the most promising regions for future development in Egypt. Fresh water supplies are crucial for such plans. We provide an integrated remote sensing (Landsat-8, SRTM, Radarsat-1, Geoeye), geophysical (aeromagnetic, gravity data), isotopic (δ18O, δ2H), field (stratigraphic and structural interpretation) and geochemi...

The origin of the Martian outflow channels (OC) remains a subject of debate. Two popular models were proposed: groundwater sapping and megaflooding. Understanding the origin of the OC can provide constraints on the presence of life on Mars and on its timing. We adopted an integrated approach (remote sensing, geo-statistical, isotopic, geotechnical...

The Quaternary wet climatic periods in north Africa and Arabia have been traditionally attributed to intensification monsoons and progressive south to north migration of the monsoonal front during interglacial periods. The intensification of the paleo-westerlies during glacial periods, not the monsoons, can account for the following observations: (...

An integrated [very low frequency (VLF) electromagnetic, magnetic, remote sensing, field, and geographic information system (GIS)] study was conducted over the basement complex in southern Sinai (Feiran watershed) for a better understanding of the structural controls on the groundwater flow. The increase in satellite-based radar backscattering valu...

The crystalline complex and overlying sedimentary sequences in southern and central Sinai are highly dissected by numerous faults, shear systems, and dikes, hereafter referred to as discontinuities. Understanding the distribution of these discontinuities, their cross cutting relations, and the hydraulic gradient gives clues as to the distribution o...

An integrated approach using remote sensing, landscape analysis and statistical methods was conducted to assess the role of groundwater sapping in shaping the Saharan landscape. A GIS-based logistic regression model was constructed to automatically delineate the spatial distribution of the sapping features over areas occupied by the Nubian Sandston...

The River Nile is the main source of fresh water in Egypt. Most of Egypt’s River Nile water (>85%) originates as precipitation over the Ethiopian highlands and is channeled by the Blue Nile. The construction (years: 2011 to 2017) of the Renaissance Dam (reservoir capacity: 70 x 109m3) on the Blue Nile poses an extreme threat to Egypt’s population....

The Nubian Sandstone Aquifer System (NSAS) is the largest groundwater aquifer in the Sahara spanning the political boundaries of four countries in north-eastern Africa; Egypt, Sudan, Libya, and Chad. The NSAS represents as a potential water resource for future development programs in these countries. Thickness of the aquifer ranges from tens of met...

We integrated (in a Geographic Information System [GIS] environment) observations from remote sensing data (Gravity Recovery and Climate Experiment [GRACE], Environmental Satellite [Envisat], Tropical Rainfall Measuring Mission [TRMM], Landsat Thematic Mapper [TM], Google Earth images) with geophysical (Very Low Frequency [VLF], Vertical Electrical...

This paper attempts to utilize observations extracted from remote sensing data sets and available published data (e.g., geologic and soil maps) to characterize the physical environment of Gebel El-Hamza area (area: (1116 km2) on the northeast fringes of Greater Cairo, Egypt. The term “physical environment” encompasses the climatic, geological, geom...

The groundwater flow and potentiality for groundwater accumulation in the fractured basement rocks and the overlaying alluvial deposits were examined in Wadi Feiran basin using remote sensing (Landsat ETM, Ikonos, and Envisat, TRMM, and SIR-C radar images), field (well location, depth to water table), and geophysical (Very Low Frequency [VLF], magn...

Paleoclimatic regimes of the North African Sahara Desert alternated between dry and wet periods throughout the Pleistocene Epoch and it is during these wet periods that the fossil aquifers in North Africa were recharged. The largest of these aquifer systems is the Nubian Sandstone Aquifer System (NSAS; area: 2.2 million km2) in Egypt, Libya, Sudan...

Compilation between the previous studies about the river systems evolution and integrating them with the remotely sensed data-based landscape analysis provide a new vision to the river systems evolution in Egypt during the Cenozoic Era. Relics of geomorphologic features left in the old basins related to these rivers suggest the existence of a natur...

The spatial characteristics of land cover are useful for understanding the various impacts of human activity on the overall ecological conditions of the urban environment. The multi-temporal Landsat images (TM) between the years of 1990 and 2003 were used together with the Geographic Information System (GIS) techniques to evaluate the environmental...