Egyptian Desert Research Articles

The use of remotely sensed data to reveal geologic, structural, and hydrologic features and predict potential areas of water resources in arid regions

Egypt’s arid deserts resemble the Sahara. They lack water resources because of climatic conditions, although the high topographic areas receive rainfall during sporadic storms. In this article, integrating radar Advanced Land Observing Satellite (ALOS)/Phased Array type L-band Synthetic Aperture Radar (PALSAR), Landsat-8, Sentinel-2, and Shuttle Radar Topography Mission (SRTM) data reveal the geological, geomorphic, structural, and hydrological features in Wadi Batur (WB), Egypt. This defunct tributary of the Nile basin, in the eastern Egyptian desert, covers approximately 6600 km2. Analysis of the remotely sensed data shows that the northwest–southeast structures control the structures discussed in this study, which are later captured by the east–west trend. A fused ALOS/PALSAR and Landsat-8 image reveals two water outlets for the WB: one extends between the Precambrian and Phanerozoic rocks and drains in a northwestern direction to Wadi Matula in the north, and the second cuts the sedimentary rock and drains to the west, at Idfu. Ten sub-basins were extracted by using SRTM data and arranged by their infiltration properties. Eight evidential maps were combined after assigning a weight to each, and a Geographic Information Systems (GIS) technique was used to predict the groundwater recharge potential zones (GPZs). The results show that the predicted GPZs in the WB fall into six categories, ranging from excellent to bare/absent. Importantly, about 10% of the surface areas in the WB basin are characterized by an excellent recharging potential and represent the most promising zones for future groundwater extraction. Combining various datasets derived from satellite sensors is a substantial tool to detect geological features and explore groundwater resources in arid environments.

Measurements of Radioactivity Concentrations in Granites and Sedimentary- Rocks and their Leaching Components in Egyptian Deserts


 
 
 Concentrations of radionuclides in sediments and granite samples were determined by γ- ray spectrometer using High Pure Germanium Detector; HPGe, with a specially designed shield. Six different rock samples were collected from different sites: four samples of sediments from Um Bogma southwest Sinai, and two granite samples from Gabal Gattar, the northern part of the East- ern Desert of Egypt, where all samples were subject to investigation. Their samples were selected because the activity before being dissociated in sulfuric acid was less than after dissociation. The samples were dissolved in sulfuric acid with the same parameters of solid to liquid ratio; S/L, acid concentration, and leaching time. After the leaching process, the pregnant solution was separated from the residual, and the latter was dried. The two units, named the pregnant solutions and residu- als, were also measured radiometrically using the HPGe detector to determine the activity concen- trations (Bq/kg) of the different radionuclides of the six samples. The results showed that the rela- tion between the sum of activities of both pregnant solutions and residuals with the originals have different categories. In the sediment samples; the activity of solution+ residual was 72.37% from the original of siltstone, the activity of solution + residual was 90.02% from the original claystone sample, the activity of solution + residual was 92.6% from the original of shale, the activity of solu- tion + residual was 74.07% from the original claystone. In the granite samples, the activity of solu- tion + residual was 130.39% from the original of the first granite sample and 142.3% from the orig- inal of the second granite sample. This phenomenon varied in magnitude due to the different radio- nuclides in each sample. These variations depend mainly on the nature of the grain surfaces in the different rock types and their Pb content. As for leachability analysis, leaching experiments have been performed using sulfuric acid. The leaching efficiency (%) of uranium is estimated by the measurements of the HPGe detector. The result showed almost constant values for leachability. The non-frequent appearance of attenuation of gamma activities during leaching processes indicates that the acid solutions may have led to clean the grain surfaces and thus permit gamma activities of the inner grains to be measured. The treatment of the samples before measurements may have been needed.
 
 

Natural radiological characterization at the Gabal El Seila region (Egypt)

Stream sediment is a useful raw material used for building construction, mostly used in the desert parts of the world. Such sediment is a Naturally Occurring Radioactive Material (NORM), and, hence, it requires a radiological characterization to be used. This work aims to study the natural radioactivity in fifty points distributed in surface of stream sediments in the area of Gabal El Seila region, south-eastern desert of Egypt, since there is a lack of information about the radioactivity levels of the sediment samples from such recent growing interest area. The activity concentration of 238U, 232Th and 4 K natural radionuclides using a portable RS-230 γ-ray spectrometer were determined. Mean values are 38.51 ± 10.83, 33.35 ± 8.82, 659.18 ± 110.87 Bq/kg for 238U, 232Th, 4 K respectively. Radiological hazard indexes were computed and compared with the UNSCEAR and other worldwide ranges. All the results are statistically presented and discussed. They show that no significant radiation hazard coming from the studied area, with the most values lower than international recommended limits. The achievements of the present study fall within the measurements of natural environmental radiation in an unexplored area of great interest being a desert. The obtained results can be used as database for future research, and as tool for radiological awareness in the use of sediments as raw material.

The presence of radioactive heavy minerals in prospecting trenches and concomitant occupational exposure.

Uranium, perhaps the most strategically important component of heavy minerals, finds particular significance in the nuclear industry. In prospecting trenches, the radioactivity of 238U and 232Th provides a good signature of the presence of heavy minerals. In the work herein, the activity concentrations of several key primordial radionuclides (238U, 232Th, and 40K) were measured in prospecting trenches (each of the latter being of approximately the same geometry and physical situation). All of these are located in the Seila area of the South Eastern desert of Egypt. A recently introduced industry standard, the portable hand-held RS-230 BGO gamma-ray spectrometer (1024 channels) was employed in the study. Based on the measured data, the trenches were classified as either non-regulated (U activity less than 1000 Bq kg-1) or regulated (with 238U activity more than 1000 Bq kg-1). Several radiological hazard parameters were calculated, statistical analysis also being performed to examine correlations between the origins of the radionuclides and their influence on the calculated values. While the radioactivity and hazard parameters exceed United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) guided limits, the mean annual effective doses of 0.49 and 1.4 mSv y-1 in non-regulated and regulated trenches respectively remain well below the International Commission on Radiological Protection (ICRP) recommended 20 mSv/y maximum occupational limit. This investigation reveals that the studied area contains high uranium content, suitable for extraction of U-minerals for use in the nuclear fuel cycle.

Climate variability and paleoceanography during the Late Cretaceous: Evidence from palynology, geochemistry and stable isotopes analyses from the southern Tethys

The Late Cretaceous epoch witnessed significant changes in climate and considerable perturbations in the global carbon cycle, among others leading to Oceanic Anoxic Events (OAEs). Investigating the paleoceanographic setting in the southern Tethys (northern Egypt) is critical for a better understanding of the triggering mechanisms that occurred during deposition as a result of a greenhouse climate. Here we present bulk rock geochemical and stable isotopic proxies from the biostratigraphically well constrained Abu Roash A Member (180 m thick) deposited through the late Coniacian–earliest Campanian in the Abu Gharadig Basin of the north Western Desert of Egypt, to investigate whether there was a record of OAE3 and deposition of organic rich facies or oxic Cretaceous Oceanic Red Beds (CORBs). Paleoclimate in this low-latitude Tethyan setting was investigated, where warm to hot greenhouse climate prevailed based on specific dinoflagellate cyst taxa and regional correlation of the δ18Ocarb trends, despite a long-term temperature fall from the mid–Santonian onwards. Low river discharge and terrigenous input during arid conditions, inferred from elemental geochemistry and clay mineralogy, led to low marine productivity during enhanced carbonate production, and thus triggered low organic matter accumulation. The neodymium isotope signatures from bulk carbonate fractions along with available coupled ocean-atmosphere climate models indicate that the studied area witnessed a westward Tethys circumglobal current. These paleocirculation patterns caused enhanced water mixing, resulting in enhanced water column ventilation. These settings led to the deposition of organic-poor CORBs and the absence of the organic-rich OAE3 deposits.

Assessment of seawater intrusion under different pumping scenarios in Moghra aquifer, Egypt

The Moghra aquifer has shown promise in land reclamation projects conducted in the Western Desert of Egypt. Although this aquifer has hundreds of pumping wells in new urban communities built to meet the needs of the increased population, the system is threatened by the phenomenon of seawater intrusion (SWI). The present study evaluates the degree to which these pumping wells will attract seawater to the aquifer system in the Western Desert region under different pumping conditions. Using the SEAWAT module of Groundwater Modeling System (GMS) software, a three-dimensional (3D) finite-difference model is built to simulate the flow and salinity distribution in the Moghra aquifer considering the geological and hydrogeological characteristics of the aquifer system. The procedure used to solve the mathematical model relied on merging two different approaches. The first approach described the dividing lines of the transition zone due to the SWI. The second approach was applied to conduct the perfect calibration process for the aquifer system. The results show that the flow and quality of the groundwater aquifer are affected by pumping. The water level and salinity are predicted under different pumping rates, a fivefold increase in the pumping rate results that the salinity increased between 4% and 26.8% according to the well location. Moreover, the drawdown values reached 162 m, which is about 46.3% of the saturated thickness.

Subduction to post-collisional volcanism in the Northern Arabian-Nubian Shield: Genesis of Cryogenian/Ediacaran intermediate-felsic magmas and the lifespan of a Neoproterozoic mature island arc

The Neoproterozoic intermediate-felsic volcanic rocks in the Wadi Ambagy area, Eastern Desert of Egypt, comprise three units: Dokhan intermediate-felsic volcanics, post-Dokhan felsic volcanics and felsites. The Dokhan lavas are generally porphyritic and composed of andesite and dacite with subordinate basalt, whereas the post-Dokhan felsic volcanics are represented by phyric and aphyric rhyolites. The medium-K calc-alkaline nature, LILE enrichment, Ta-Nb anomalies and LREE-enriched patterns of the Dokhan volcanic rocks are consistent with development in a subduction setting. Arc crustal thickness estimation using average (La/Yb)n is ~ 32 km, indicating that these rocks were generated in a Neoproterozoic island arc with thick crust. The subduction magmas were generated by hydrous mantle melting and they evolved by fractional crystallization. In contrast, the post-Dokhan felsic volcanics and felsites have medium- to high-K and shoshonitic affinities, respectively. They are highly silicic with weak to absent Ta-Nb anomalies and significant Nb, Zr, Hf and REE enrichment, which increases from the post-Dokhan felsic volcanics to the felsites. These geochemical features suggest generation in a post-collisional to within-plate tectonic setting by partial melting of mafic or intermediate arc crustal sources. SHRIMP U-Pb zircon dating indicates a crystallization age of ~ 660 Ma for the subduction-related Dokhan andesite and dacite, reflecting a magmatic arc lifespan longer than previously considered. The change of setting from subduction to post-collisional was accompanied by an increased role of crustal sources in the generation of the felsic magmas, resulting in differentiation of the accreted arc crust.

Characteristic of gold mineralization associated with granites at Hamash old gold mine, South Eastern Desert, Egypt

Well-known controversy over the genesis of orogenic gold mineralization in granites has been a subject of research worldwide. Hamash gold mine is considered one of the pharaohs mines in the South Eastern Desert of Egypt, where gold mineralization is hosted by granites. In this study, we utilized field, ore microscopy, and geochemical data to determine the genesis of granites and the associated gold deposits. We found that the granites, intruded into island-arc metavolcanics and metavolcanoclastic assemblages, are characterized by variable major and trace elements, calc-alkaline, and I-type granitoids that reflect a fractional crystallization. Their trace and rare earth elements reflect magma that is related to subduction tectonic setting. The gold mineralization is confined to quartz veins that cut through granitic rocks, extend in NW-SE and N-S directions, and are formed during shear-extensional tectonics. The gold is found with sulfides in quartz veins and wallrock alteration. Silicification and sericitization are the most hydrothermal alteration zones associated the ore formation, comprise an inner quartz-sericite-carbonate-chlorite-sulfide assemblage. The results of chemical analysis reveal an increase of SiO2, Fe2O3, S, and L.O.I. concentrations and moderate depletion in K2O, Na2O, and LILE suggesting that they were affected by mineral replacement reactions and sulfidation in the altered wallrocks close to Au-quartz veins. The gold is represented by tiny inclusions, with minor chalcopyrite, galena, and arsenopyrite that mainly fill the microfracture in quartz and pyrite grains. Furthermore, a general model of gold mineralization suggests that the gold was contemporaneously formed during syn-orogenic stage, transpressional deformation assigned to D2 deformation, and subduction-related thermal processes followed by gold-bearing fluids that fill the fractures, forming veins.

Assessment of radon radiological hazards in some ophiolite rocks, North Eastern Desert, Egypt

The natural stones are commonly used as interior and exterior building material. The accessory minerals of some rocks can generate a high amount of radon in the atmosphere. Ophiolitic rocks including serpentinites, metagabbros, gabbros metabasalts, metabasaltic-andesites, meta-andesites, Dokhan andesites, dacites, rhyolites, quartz diorites, tonalites, granodiorites, monzogranites and syenogranites. From the Eastern Desert of Egypt were analyzed for radon. The annual effective dose values of all studied rocks are higher than the world average due to the high radon content in the samples. The studied rocks are not recommended to be used as construction material.

Development of a Spatial Model for Soil Quality Assessment under Arid and Semi-Arid Conditions

Food security has become a global concern for humanity with rapid population growth, requiring a sustainable assessment of natural resources. Soil is one of the most important sources that can help to bridge the food demand gap to achieve food security if well assessed and managed. The aim of this study was to determine the soil quality index (SQI) for El Fayoum depression in the Western Egyptian Desert using spatial modeling for soil physical, chemical, and biological properties based on the MEDALUS methodology. For this purpose, a spatial model was developed to evaluate the soil quality of the El Fayoum depression in the Western Egyptian Desert. The integration between Digital Elevation Model (DEM) and Sentinel-2 satellite image was used to produce landforms and digital soil mapping for the study area. Results showed that the study area located under six classes of soil quality, e.g., very high-quality class represents an area of 387.12 km2 (22.7%), high-quality class occupies 441.72 km2 (25.87%), the moderate-quality class represents 208.57 km2 (12.21%), slightly moderate-quality class represents 231.10 km2 (13.5%), as well as, a low-quality class covering an area of 233 km2 (13.60%), and very low-quality class occupies about 206 km2 (12%). The Agricultural Land Evaluation System for arid and semi-arid regions (ALESarid) was used to estimate land capability. Land capability classes were non-agriculture class (C6), poor (C4), fair (C3), and good (C2) with an area 231.87 km2 (13.50%), 291.94 km2 (17%), 767.39 km2 (44.94%), and 416.07 km2 (24.4%), respectively. Land capability along with the normalized difference vegetation index (NDVI) used for validation of the proposed model of soil quality. The spatially-explicit soil quality index (SQI) shows a strong significant positive correlation with the land capability and a positive correlation with NDVI at R2 0.86 (p < 0.001) and 0.18 (p < 0.05), respectively. In arid regions, the strategy outlined here can easily be re-applied in similar environments, allowing decision-makers and regional governments to use the quantitative results achieved to ensure sustainable development.

Building a Model to Reconstruct the Hellenistic and Roman Road Networks of the Eastern Desert of Egypt, a Semi-Empirical Approach Based on Modern Travelers’ Itineraries

The Egyptian Eastern Desert, the part of the Sahara Desert that connects the Nile and the Red Sea, is rich in natural resources and meshed with multiple networks. The adoption of the camel as the main mode of transportation in the 1st millennium BC, faster and with a greater load capacity than humans or donkeys, dramatically changed the logistics used to cross this difficult terrain. Our objective, therefore, is to understand and reconstruct circulation in the region during Antiquity through location factors and the evolution of roads. For this purpose, a least-cost network specific to camel movements has been created for this arid and mountainous region. The network is based on the reconstructed itineraries of modern travelers (18th and 19th centuries) who crossed the region under similar conditions to ancient ones. These routes and the travelers’ diaries have enabled us to analyze the main travel constraints; they provide a set of data to calibrate the different movement factors of camel caravans and to validate the calculated least cost paths. The modeled network takes into account transport infrastructures, navigation conditions in plain areas, difficulties of the terrain surface, and the topographical constraints specific to camels. This methodological paper details our approach from the description of movement factors, their mapping, and their use in least cost algorithms to the creation of a network covering 253 archaeological sites and 204 desert watering places. It aims to provide the archaeological and GIS communities with the method and tools to reproduce itineraries based on the hypotheses of movement and empirical data. For this purpose, the data is available and documented by a data paper.

Evaluation of Essential Oils in Two Artemisia Species that are Grown Wildly in Eastern Desert of Egypt

The aerial parts of Artemisia judaica L. (A. judaica) and Artemisia monosperma (Delile) (A. monosperma) were collected from wild plant populations located in the eastern desert of Egypt. The essential oils (EOs) of both aerial parts were isolated by hydro-distillation (HD) and analyzed by GC/MS. The EO yields of A. judaica and A. monosperma were 6.0 and 4.0 ml/500 g herb, respectively. Piperitone (43.8 % ± 3.6), artemisia ketone (38.3 % ± 3.2) and artemisia alcohol (3.1 % ± 0.6) were the main components of A. judaica EO, while the major components of A. monosperma EO were β-pinene (56.4 % ± 4.8), δ-cadinene (18.4 % ± 2.1), α-pinene (6.8 % ± 0.9), limonene (5.4 % ± 1.1) and cis-β-ocimene (3.1 % ± 0.5). Various constituents of A. judaica EO belonged to monoterpene hydrocarbons (MH) and oxygenated monoterpenes (OM). The chemical groups of A. monosperma EO were MH, OM, sesquiterpene hydrocarbons (SH), and oxygenated sesquiterpenes (OS). The major chemical classes of A. judaica and A. monosperma EOs were OM (90.3 % ± 6.1) and MH (77.4 % ± 4.9), respectively.

<p><strong>Comparison of Egyptian and Saudi <em>Mesembryanthemum forskalii </em>Hochst. ex Boiss. as an unconventional alternative protein of wheat and barley</strong></p>

Mesembryanthemum forskalii , commonly called Forskal Fig-marigold, is a wild plant, grown naturally in Saudi and Egyptian deserts and in many countries around the world. However, nutrition value, especially its protein content, has not been studied until now. Here, we explored this plant as a new source of protein, particularly in drought or salted lands that can't be cultivated with grains and to meet the increasing of human requirements for protein. Analysis of amino acids contents showed seven essential amino acids in Egyptian and Saudi M. forskalii . Moreover, both M. forskalii have some amino acids their concentrations higher than that of wheat and barley. In addition, SDS-PAGE protein results revealed the appearance of 7 monomorphic bands in all samples; two bands appeared only in M. forskalii and not found in wheat or barley. HDN protein profile exhibited Rubisco band in all samples. The CDDP analysis indicated that M. forskalii has significant similarity with wheat or barley and share some genes with them. The observations suggest M. forskalii to be a potential new source of protein. It has many important amino acids and a valuable content of protein and can be combined or substituted with flour from cereals to enrich the diets of Saharan communities.

Detecting Crop Circles in Google Earth Images with Mask R-CNN and YOLOv3

Automatic detection and counting of crop circles in the desert can be of great use for large-scale farming as it enables easy and timely management of the farming land. However, so far, the literature remains short of relevant contributions in this regard. This letter frames the crop circles detection problem within a deep learning framework. In particular, accounting for their outstanding performance in object detection, we investigate the use of Mask R-CNN (Region Based Convolutional Neural Networks) as well as YOLOv3 (You Only Look Once) models for crop circle detection in the desert. In order to quantify the performance, we build a crop circles dataset from images extracted via Google Earth over a desert area in the East Oweinat in the South-Western Desert of Egypt. The dataset totals 2511 crop circle samples. With a small training set and a relatively large test set, plausible detection rates were obtained, scoring a precision of 1 and a recall of about 0.82 for Mask R-CNN and a precision of 0.88 and a recall of 0.94 regarding YOLOv3.

E&P Notes (March 2021)

E&P Notes (March 2021)

Palynofacies as a palaeoenvironment and hydrocarbon source potential assessment tool: An example from the Cretaceous of north Western Desert, Egypt

Optical examination employing transmitted light and UV-fluorescence microscopy of palynological preparations of eighteen cutting samples representing the Alam El Bueib Member (Hautervian-Barremian), Kharita/lower Bahariya (Cenomanian), and Abu Roash (Turonian-Santonian) formations collected from the Faghur Hj5-1 well, north Western Desert, Egypt, allows the identification of three different palynological assemblages from the studied rock units. These assemblages are mainly non-marine but apparently marine at the base of the Alam El Bueib Member, as evidenced by dinocyst occurrence. In addition, the presence of the Pediastrum and chlorophycean algae ecozone, recognised in previous works, is a good datum for the Abu Roash Formation in the north Western Desert of Egypt. Three associations of palynofacies linked to lithofacies changes are recognised and employed in identification of depositional environments. The Alam El Bueib samples yielded mixed kerogen assemblages of non-marine and marine organic facies. The Kharita/lower Bahariya interval is mostly barren, possibly due to prevailing sandstone lithofacies, except for one sample at its upper part which contains a diverse palynological assemblage. The overlying Abu Roash Formation has a homogeneous kerogen composition comprising mainly granular fluorescent AOM and algae as well as rare palynomorphs. Qualitative as well as quantitative variations of palynofacies allow the reconstruction of the depositional environment. The obtained data have the potential for discriminating spatial and redox status differences and providing also information about terrestrial/freshwater influxes. Results support the model that the Alam El Bueib Member was deposited in a marginal dysoxic-anoxic to distal suboxic-anoxic basin. The Kharita/lower Bahariya unit in the studied well was deposited under marginal dysoxic-anoxic conditions whereas the overlying Abu Roash Formation in a distal suboxic-anoxic basin. Palynofacies results also show that the studied material comprises two distinct facies of kerogen. First, Type II > I kerogen (AOM-rich) is overwhelmingly dominant in the Abu Roash Formation and a few samples from the Alam El Bueib Member which are presumed highly oil-prone, whereas Type III kerogen (phytoclast-rich) is particularly common in the Alam El Bueib Member and Kharita/lower Bahariya unit which are considered gas-prone. Thermal maturity determinations obtained from colour changes of smooth-walled palynomorphs reveal that Alam El Bueib samples belong to immature to mature stages; however, Kharita/lower Bahariya and Abu Roash samples are within the immature phase.

Integration of ASTER and geophysical data for delineating potential mineralization zones in Dungash-Atud area, Central Eastern Desert, Egypt

Dungash-Atud area, located in the southeastern Egyptian Desert, is intensively distinguished by gold mineralization and associated mineral deposits. This area was studied using the integrated analysis and interpretation of ASTER, aeromagnetic, and gamma-ray spectrometric data. For ASTER, different approaches of image processing, such as false color composite (FCC), ASTER-TIR indices, principal component analysis (PCA), and spectral mapping, have been used to determine the desired information on the geology, lithology reclassification, and the existing minerals, particularly older and younger granites, basic, and ultrabasic rocks. Also, the alteration imagery maps of different minerals, sericite, chlorite, illite, kaolinite, calcite, epidote, and quartz, are obtained and classified, in addition to Mafic and Quartz Index. The processed and interpreted aeromagnetic data helped effectively for the detection of the deep subsurface and near-surface structural elements affecting the area and inspection favorable sites of mineralization that give strong magnetization of which chromite bodies associated with serpentinite rocks. In addition, the aerospectrometric data, equivalent uranium eU, equivalent thorium eTh, potassium K%, and total count (TC), were analyzed and hence the ratio maps (eTh/K, eU/K, and eU/eTh) and ternary radioelement composite images were produced to infer the enriched sites of U and Th mineralization. The integration of these results was guided and tied with previous geological information, especially ancient and present gold mines and associated mineral deposits. Such results gave clear clue about the existing number of basic to ultrabasic parallel wide dikes injected within fault zones trending mainly parallel to the Red Sea rift tectonics (NW and NNW directions) and other faults/dikes, trending in the NE direction. The long-extended NW trending wide dykes are cutting across the whole investigated area reflecting its deeper extension. Other faults show lateral displacements representing major shear zones, trending mainly in the NE direction. The produced potentiality map using GIS technique showed that most of the ancient gold mines and/or associated mineral deposits are related and controlled greatly with the detected structural elements, dykes, and rock affinity. Hence, it is easy to follow other sites that could have a high potential for mineral deposits including a gold through further field investigation in coordination with the detailed ground geophysical survey.

Utilization of Landsat-8 Imagery and Aeromagnetic Data for Deciphering Alteration Zones and Structures: Implications for Mineral Exploration in the Southeastern Desert of Egypt

Remote-sensing (RS) and aeromagnetic data implemented notable information for mineralization potentiality detection of ore deposits within Al-Allaqi region of the southeastern Desert of Egypt. Several approaches of remote-sensing and aeromagnetic data were implemented. Results of band ratios (BR) and Principal Component Analysis (PCA) practicing Landsat-8 successfully imaging the hydrothermally altered zones and the structures outlined by lithologic contacts, faults, and porphyry features (dyke-like structures). Lineaments well extracted using aeromagnetic datasets. CET system method was applied for generating a heat map of the structural complexity. Likewise, the CET Porphyry Analysis system was performed to extract the likely near-circular porphyry features that revealing a probable site of mineralization and to validate the remote sensing observations. Integrated outcomes showed that areas of highly complex structures, density (fractures/faults) are consistent with the detected hydrothermally altered areas that are rivaled with mining zones in Al-Allaqi region of the Southeastern Desert of Egypt. This approach can be broadly appropriate to other divisions of the Southeastern Desert of Egypt for mineral prospecting.

Palynomorph biostratigraphy, palynofacies, thermal maturity and paleoenvironmental interpretation of the Bajocian–Aptian succession in the OBA D-8 Well, Matruh Basin, Egypt

A palynological study of 35 cutting samples from the Middle Jurassic–Lower Cretaceous section encountered in the OBA D-8 Well in the north Western Desert of Egypt yielded palynomorphs and particulate organic matter used to interpret the biostratigraphy, palynofacies, paleoenvironment, thermal maturation, and hydrocarbon potential of the Matruh Basin. The stratigraphically significant dinoflagellate cyst and sporomorph taxa recovered, which include Murospora florida, Aequitriradites spinulosus, Pilosisporites trichopapillosus, Callialasporites trilobatus, Tenua anaphrissa, Muderongia simplex, Systematophora sp., Gonyaulacysta jurassica, Korystocysta gochtii, Pareodinia ceratophora, and Dissiliodinium sp., permit an age assignment of the studied section as Bajocian to Aptian. Seven formal dinoflagellate cyst zones and four formal sporomorph zones are proposed for this time interval, in addition to differentiating four palynofacies assemblages and using the Rock-Eval Pyrolysis method to visually and geochemically evaluate the source rock potential. The 0.45–2.82 wt% TOC values of the studied samples indicate fair to good source rocks. An inner neritic depositional environment due to relatively high sea level is deduced for the Khatatba and Masajid formations using palynological proxies, as reflected in the lower percentages of sporomorphs relative to dinoflagellate cysts. During the Lower Cretaceous, a predominance of terrestrial sporomorphs in the Alam-El Bueib Formation suggests the advance of a fluvio-deltaic environment, possibly related to a significant sea level fall and regressive phase.

Adaptive eco-physiological mechanisms of Alhagi graecorum in response to severe aridity in the Western Desert of Egypt

The present work aimed to evaluate some eco-physiological responses of Alhagi graecorum to elucidate its osmotic adjustment and physiological adaptation mechanisms to withstand hyper-aridity. The plant samples were collected from eight locations in the Dakhla Oasis during the winter and summer of 2017. The chlorophyll (Chl a & b) contents and their ratio increased significantly during summer enabling the plants to adapt to light condition changes. There was a greater accumulation of anions and cations in plant tissues during winter more than in summer except, for K +that exhibited the opposite trend during summer. Soluble sugars (SS) and soluble proteins (SP) were higher than total free amino acids (TAA) during summer. The total phenolics (Ph) and total antioxidants (Anti. Ox.) in this plant were higher during winter than in summer; whereas total flavonoids (Flav) displayed the opposite response. The results indicated close relationships among the high macronutrient contents, cool-moist conditions, and Ph and Anti. Ox. accumulation in winter. Ph and Anti. Ox. served as active compounds for perseverance or raw material for metabolic processes that let such plants maintain an abundant rate of growth under severe arid conditions. ABBREVIATIONS A. graecorum: Alhagi graecorum; AA: ascorbic acid; Anti.Ox: total antioxidant; BSA: bovine serum albumin; Chl: chlorophyll; DW: dry weight; Flav: flavonoids; FW: gresh weight; L: location; OM: organic matter; Ph: phenolic; PWC: plant water content; Se: season; SP: soluble protein; SS: soluble sugars; TAA: total free amino acids; TCA: trichloroacetic acid; TSS: total soluble salts