Northwestern Egypt Research Articles

The Reservoir potential of Middle Jurassic sedimentary deposits in the Imhotep Field, Matruh Basin, North-Western Egypt

The Reservoir potential of Middle Jurassic sedimentary deposits in the Imhotep Field, Matruh Basin, North-Western Egypt

3D geological and petrophysical modeling of Alam El-Bueib Formation using well logs and seismic data in Matruh Field, northwestern Egypt

There are several productive petroleum fields in the North Western Desert (WD) of Egypt, which received extensive investigations regarding their petroleum potential. However, a few studies tackled the Matruh Oil Field, which contains the oil prolific Early Cretaceous Alam El-Bueib Formation (AEB Fm) reservoir. The reservoir intervals of the AEB Fm show substantial lithological variations across the basin. Therefore, it is necessary to analyze the vertical and lateral distributions in terms of their lithological and petrophysical properties. To achieve this objective, wireline logs of four wells and 20-2D seismic lines were used to construct a depth-structure contour map for the studied part of the field. This map was used to build the field’s structure model and to identify the fault patterns in the basin through several seismic lines. Analyses of well logs data and lithology were used to estimate the petrophysical properties of AEB sandstone units AEB-1, AEB-3A, AEB-3C, and AEB-6. Results show that the AEB-6 Unit is the most promising hydrocarbon-bearing unit. It has a net pay of 20–160 feet, a shale volume of 5–20%, an effective porosity of 14–20%, and a hydrocarbon saturation of 70–88%. The structure-depth maps indicate a number of normal faults with two principal NE-SW and NW–SE trends, which probably act as structural traps in the Matruh Oil Field. The constructed structure-depth maps and calculated petrophysical parameters were used to build a three-dimensional reservoir model. A blind well was used to validate the accuracy and reliability of the facies, porosity, and saturation models for the AEB Fm units, ensuring a good match between log-derived data and built models. The AEB Fm shows regional heterogeneous variations in its petrophysical characteristics. It exhibits unconventional reservoir characteristics in a N–S direction and conventional reservoir characteristics in an E–W direction. This observed heterogeneity shows the need to carry out further investigations to comprehensively assess the hydrocarbon potential of AEB Fm in different areas of the Matruh Basin.

Organic petrographic, geochemical, and sequence stratigraphic analyses for evaluating the hydrocarbon potential of Middle Jurassic–Lower Cretaceous rocks in Shushan Basin, northwestern Egypt

Integrated organic petrographic and geochemical analyses were made on organic-rich marine carbonate and mixed clastic-carbonate rocks of Middle–Late Jurassic and Early Cretaceous age from the Shushan Basin, Egypt to evaluate their hydrocarbon potential. Analyses allowed the identification of depositional settings, paleoclimate, and three third order genetic stratigraphic sequences (SQ) with deposits assigned to highstand (HST), lowstand (LST) and transgressive systems tracts (TST). Deposition of the source rocks in the rifting Shushan Basin resulted from the interaction between Neotethyan sea level changes, tectonic, and climate. The good reducing conditions developed during the Neotethyan Middle–Late Jurassic (Bajocian–Kimmeridgian) second order sea level rises and the climatically induced carbonate sedimentation resulted in the deposition of the organic-rich carbonates of the Khatatba Formation (SQ 1, early–middle TST) in inner–middle shelf settings under anoxic–dysoxic conditions. The Late Jurassic (late Kimmeridgian) uplifting resulted in the deposition of the organic-lean mixed clastic–carbonate strata of the Masajid Formation (SQ 1, latest TST) in the same shelfal and reducing conditions, which experienced a notable dilution of organic matter. The late TST deposits of SQ 1 are good to very good oil-producing source rocks, where they show average good to very good generative potential of late mature (late oil-to early wet gas-window) highly oil-prone organic matter. The Early Cretaceous (Valanginian–Albian) uplifting associated with the rifting of the Shushan Basin overprinted the Neotethyan late Valanginian–Hauterivian second order sea level rises, Aptian second order highstand sea level, and Albian second order sea level rise. The coeval climatic shift toward more humid conditions resulted in the clastic-dominated deposition of the organic-lean regressive units of SQ 2 (HST and LST of Alam El Bueib, Alamein, and Dahab formations) and SQ 3 (HST and LST of the lower–upper Kharita Formation) in marginal marine settings under anoxic–dysoxic to oxic conditions. The HST and LST deposits of the SQ 2 and SQ 3 show poor to good organic richness of early–mid mature (early–peak oil-window) oil/gas-prone and gas/oil-prone organic matter, respectively and exhibit average fair oil source rock potential with no gas generation.

Clustering of children’s oral diseases in families and villages in a rural setting in Egypt

BackgroundThis study assessed the clustering of children’ caries experience, plaque accumulation and gingival inflammation in families and villages in Northwestern Egypt and the factors related to the severity of these conditions.MethodsThis was a secondary analysis of a 2019 household survey of children in villages around Alexandria, Egypt. Clinical examination assessed primary and permanent teeth caries experience (dmft/ DMFT using the World Health Organization criteria), plaque accumulation (Plaque Index (PlI)) and gingival inflammation (Gingival Index (GI)). A child questionnaire assessed child’s age, sex, the frequency of toothbrushing (at least twice daily versus less) and frequency of consuming eight types of sugary products (daily sugar consumption score, sum of sugary products consumed daily). Mothers’ questionnaire assessed the number of children in the family, mother’s education (at least high school versus less), at least twice daily toothbrushing and daily sugar consumption similar to the child. Multilevel regression analyses assessed clustering, calculated by the intraclass correlation coefficient (ICC) of the three conditions in families and villages. Regression estimates (B) and 95% confidence intervals (CIs) of individual and family factors were calculated.ResultsComplete data were available for 450 children (246 families, seven villages], mean = 9.9 years-old and 56% females. The mean caries experience score = 3.6, mean plaque index = 1.5 and mean gingival index = 1.2. Caries experience, plaque accumulation and gingival inflammation were not clustered in villages (ICC < 0.01) but clustered in families (ICC = 0.10, 0.44 and 0.29). Child factors significantly improved model fit for caries experience and gingivitis (p < 0.001) but not plaque accumulation (p = 0.90). Family factors did not improve any model fit (p > 0.05). Child’s age was significantly associated with caries experience (B= -0.48, p < 0.001) and gingival inflammation (B = 0.032, p < 0.001). Children who brushed their teeth twice daily had significantly more caries experience (B = 1.04, p = 0.01).ConclusionThe three oral conditions were not clustered in villages but clustered in families. Plaque accumulation showed the greatest within-family clustering. Family factors were not associated with the three conditions and individual factors indicated the need for interventions to promote preventive behaviors and identify families at risk of oral conditions.

The Emergence of Terrace Farming in the Arid Zone of the Levant—Past Perspectives and Future Implications

Terrace farming installations occupy vast desert areas in the Southern Levant. Their construction in harsh environments raises critical questions focusing on the natural, political, and economic circumstances promoting their construction and operation. The present review, based on new observations and previously published materials, focused on three different arid regions located across the Southern Levant, namely the Eastern Marmarica of Northwestern Egypt, the Negev Desert of Israel, and the Petra region in Jordan. The comparison between the regions allows us to uncover the forces behind this vast phenomenon, and to draw conclusions on the relevance of these arid zones to past and present agricultural productivity. The results of this study showed that the environmental conditions in the Southern Levant provided soil and water throughout the entire Holocene, and that terrace farming was a well-known method to the early inhabitants of the region. However, the actual implementation of the vast phase of terrace farming was diachronic across the region, according to the political and economic circumstances promoting their construction at each location. As enhanced desertification is expected to accelerate during the coming decades, the maintenance of agricultural terraces is vital for the conservation of agricultural productivity in the forthcoming warming world, especially in arid lands.

Influence of environmental-friendly bio-organic ameliorants on abiotic stress to sustainable agriculture in arid regions: A long term greenhouse study in northwestern Egypt

The problem of soil salinity is rapidly increasing, with more than 950 million hectares affected by salinity stress (Arora et al., 2017). The amelioration of saline-sodic soils using chemical ameliorates could increase CO2 emissions and soil degradation. Therefore, amending saline-sodic soil with environmentally friendly bio-organic ameliorants such as brewer's spent grain (SG) and Azospirillum (A. brasilense) bacteria could represent a safe and cheaper approach compared to other organic (compost; CT) and mineral fertilizers. Under greenhouse conditions, maize was grown in saline-sodic soil amended with bio-organic ameliorants. Nine treatments were included; (i) SG1 (23.8 t ha−1); (ii) SG2 (47.6 t ha−1); (iii) TC1 (23.8 t ha−1); (iv) TC2 (47.6 t ha−1); (v) injection of A. brasilense with corn seeds (Az); (vi) combination of A. brasilense and SG (Az + SG1); (vii) combination of A. brasilense and compost (Az + TC1); (viii) mineral fertilizers (NPK) and (ix) the control (CK). The results revealed that soil amended with Az and SG2 significantly decreased the exchangeable sodium percentage (ESP) and higher cation exchange capacity (CEC). Compared with the control, the exchangeable sodium (Ex-Na+) concentration was decreased by 53.2 and 49.27%, for Az and Az + SG1 treatments, respectively. The fresh- and dry weight observed for Az + SG1, SG2, and Az treatments were increased compared to TC1, TC2, NPK, and CK treatments. The grain and biological yields were higher in Az + SG1 and SG2 than in TC2, NPK ameliorants, and CK. The bio-organic ameliorants alleviated the abiotic stress, enhance the growth and productivity of corn plants, decrease soil ESP and Na+ content, and enhance soil fertility. In conclusion, the application of SG2 can enhance the growth, and productivity of maize grown under salinity-sodicity stress. Therefore, SG2 and Az + SG1 are recommended for direct application in saline-sodic soil.

3E enhancement of freshwater productivity of solar still with heater, vibration, and cover cooling

This study focused on experimentally increasing the productivity of freshwater from solar stills. The performance of a single solar still system could be augmented with the combination of an electric heater, vibration motion, and thermoelectric cooling. The study investigated the effects of combining two of these components and finally combining all of them on freshwater productivity. The electric heater and vibration motion are used to enrich the evaporation rate, while thermoelectric coolers are used to enhance the condensation rate, leading to high freshwater productivity. The proposal, construction, and testing of two identical solar stills were performed under the local climate conditions of the city of Alexandria in northwestern Egypt during the summer and winter times. The two solar stills had a 1-m2 base area. An electric heater of 450 W was placed inside the modified solar still. The modified solar still was fixed on four coiled springs. A 1-hp power DC motor, an inverter, a control unit, and two 330-W photovoltaic solar panels were attached to the modified solar still. Eccentric masses were mounted on the rotating disk attached to the DC motor to generate the vibration. Under the same climate conditions, the daily output of freshwater was measured experimentally for the modified case and the conventional solar. The daily rates of freshwater productivity in summer were investigated for four cases and the conventional one. Results showed that the peak daily freshwater productivity achieved with the solar heater, thermoelectric coolers, and vibration motion was 12.82 kg/day, with a maximum estimated cost of 0.01786 $/L/m2.The exergoeconomic of the modified solar still with heater, vibration, and thermoelectric cooler was greater than that of conventional ones. The highest CO2 mitigation of the case (5) and that of the conventional solar desalination were about 160 tons and 28 tons, respectively.

Morphological identification and molecular characterization of economically important ticks (Acari: Ixodidae) from North and North–Western Egypt

Ticks represent a major source of growing economic and public health concern, especially in the tropics and sub-tropics. Towards evidencing ticks’ invasion in the North and North–Western parts of Egypt, the present study aimed to investigate the morpho-molecular aspects of those ectoparasites using stereomicroscopy, scanning electron microscopy (SEM) and sequencing of the mitochondrial 16S ribosomal DNA gene (rDNA) and nuclear second internal transcribed spacer (ITS2). Our analysis confirmed the presence and well–distribution of Rhipicephalus sanguineus s.l. infesting dogs and sheep (Alexandria governorate), Rhipicephalus annulatus infesting cattle (Beheira governorate), and Hyalomma dromedarii infesting camels (Marsa Matruh governorate) from North/North–Western Egypt. 16S rDNA and ITS2 sequences of the ticks were amplified using universal and gene–specific sets of primers, sequenced and analyzed. Lengths of amplified 16S rDNA sequences in all examined tick species were found to be similar in size (approximately 460 bp); however, they differed in base pair constitutions, whereas ITS2 lengths were 1,500 bp, 1,550 bp, and 1,800 bp for Rh. annulatus, Rh. sanguineus s.l., and Hy. dromedarii, respectively. Phylogenetically, based on the 16S rDNA results, Rh. sanguineus s.l. ticks clustered with the southeastern Europe lineage from Romania and Greece, Rh. annulatus ticks were similar to Turkish populations, and Hy. dromedarii were close to the isolates from Tunisia. Similarly, based on ITS2 sequences, Rh. sanguineus s.l. from dogs were showing 99% similarity to Nigerian populations; however, those collected from sheep were closer to Iranian populations with 4.1% nucleotide divergence between the two populations of different hosts. Rh. annulatus ticks were identical to a population from Romania, whereas Hy. dromedarii was close by 99.7% similarity to a population from Kenya. This is the first study reporting nucleotide sequences of 16S rDNA and ITS2 in integration with morphological identification of ticks from this part of Egypt.

Integrated organic geochemical/petrographic and well logging analyses to evaluate the hydrocarbon source rock potential of the Middle Jurassic upper Khatatba Formation in Matruh Basin, northwestern Egypt

The present national and international pursuit of converting Egypt into a regional hub of natural gas in the East Mediterranean region resulted in conducting extensive exploration activities in several areas of northern Egypt. Therefore, organic petrographic, geochemical, and geophysical analyses were carried out on the upper Khatatba Formation from the OBA 2-2A well in the Matruh Basin.Restoration of the original sedimentological and geochemical characteristics of the upper Khatatba Formation suggest deposition of this formation in deltaic settings. Few shale and partly calcareous shale units of the Upper Safa and the uppermost Zahra members accumulated in TST in prodelta settings under dysoxic-anoxic conditions. These shale units had an original gas/oil-prone organic facies BC. Other shales and partly calcareous shales of the Upper Safa and Zahra members accumulated in HST in deltafront settings under relatively oxic conditions and had an original lower gas-prone organic facies C.The Upper Safa Member had an original active fair to excellent organic richness (0.76–7.35, avg. 3.38 TOCo(live) wt%) and hydrocarbon source rock potential (S2o: 2.22–17.97, avg. 8.05 mg HC/g org. C). It was characterised mainly by original active mixed gas/oil-prone kerogen type IIIo(live)-IIo(live) (HIo(live): 200.27–297.34, avg. 238.03 mg HC/g TOCo(live)) and subordinately by gas-prone kerogen type IIIo(live) (HIo(live): 181.50 mg HC/g TOCo(live)). The Upper Safa Member had original poor to fair proportions of active oil-prone (0.15–1.47, avg 0.68 TOCo(live, oil) wt%) and higher fair to very good proportions of active gas-prone (0.61–5.88, avg. 2.70 TOCo(live, gas) wt%) kerogens. The Upper Safa Member originally possessed poor to very good oil (S2o(oil): 0.44–3.59, avg. 1.16 mg HC/g org. C) and good to very good gas (S2o(gas): 1.77–14.37, avg. 6.44 mg HC/g org. C) generation potential. The carbonates and partly calcareous shales of the uppermost Safa and the Zahra members possessed poor oil and gas generation potential due to their organic-lean status.The present-day organic geochemical characterization indicates that the Upper Safa Member still shows active fair to excellent organic richness (0.68–6.75, avg. 3.11 TOCpd(live) wt%). However, this member shows a relatively lower present-day good to very good/excellent source rock potential (S2pd: 1.33–10.78, avg. 4.83 mg HC/g rock) and lower active kerogen quality IIIpd(live) (HIpd(live): 115.97–198.21, avg. 151.07 mg HC/g TOCpd(live)). This is related to the current high thermal maturation (gas-window: Tmax: 459–468, avg. 469 °C, thermal alteration index: TAI of 4-) and conversion of the original kerogen IIIo(live)-IIo(live) into oil and gas. The present-day high organic richness, high remaining generative potential, high shale volume of the thermally mature gas-prone kerogen, classify the Upper Safa Member as an active fair to excellent shale gas play in the Matruh Basin. Intrabasinal and interbasinal correlations across northwestern Egypt indicate that the upper Khatatba Formation shows locally and regionally dual source and reservoir rock characteristics due to the lateral facies changes.

Parenting practices and oral health behaviors of children in rural Egypt: gender differences in a household survey

BackgroundParenting practices influence children’s health and development. The current study aimed at assessing gender differences in children’s perception of the parenting practices of both parents, and in the association between children’s oral health behaviors and parenting practices.MethodsA cross-sectional household survey of 6–12 year old children was conducted in a rural area in Northwestern Egypt in 2019. Clinical examination assessed caries and gingivitis. The Alabama Parenting Questionnaire assessed parenting practices in five domains (positive parenting, involvement, inconsistent disciplining, poor monitoring and corporal punishment) and the World Health Organization questionnaire assessed oral health behaviors including sugar consumption and daily toothbrushing. Sugar consumption was the dependent variable in linear regression and daily toothbrushing was the dependent variable in logistic regression. Parenting practices were the explanatory variables adjusting for confounders. Effect modification by child gender was assessed.ResultsThe response rate was 94.1% (n = 433), mean age = 9.9 years, 44.1% boys, 17.8% with daily toothbrushing and mean sugar consumption score = 3.4/8. Girls perceived more mothers’ positive parenting than boys (mean = 14.15 and 13.46) and boys perceived more poor monitoring and corporal punishment. Boys and girls differed in the association between sugar consumption and fathers’ inconsistent disciplining, poor monitoring (P = 0.004 and 0.02) and mothers’ corporal punishment (P = 0.02), and also daily toothbrushing and mothers’ involvement, positive parenting (P = 0.05 and 0.02), fathers’ positive parenting (P = 0.02), mothers’ inconsistent discipling and poor monitoring (P = 0.01 and 0.04).ConclusionsThere were differences between boys and girls in perceiving mothers’ and fathers’ parenting practices and in the association between these parenting practices and toothbrushing and sugar consumption.

Growth, Yield, and Bunch Quality of "Superior Seedless" Vines Grown on Different Rootstocks Change in Response to Salt Stress.

The growth and quality of vines are negatively affected by soil salinity if enough salts accumulate in the root zone. As part of the current study, we estimated the remediating effects of rootstocks under salinity. For this reason, “superior seedless” vines were grafted onto three different rootstocks, such as SO4, 1103 Paulson, and own-root (“superior seedless” with their own-root). The experiment was conducted in the 2019 and 2020 seasons. This study examines the effects of different rootstocks on vine growth, yield, and quality using “superior seedless” vines grown in sandy soil with salinity. Four stages of berry development were examined (flowering, fruit set, veraison, and harvest time). At harvest, yield characteristics (clusters per vine and cluster weight) were also assessed. Each parameter of the growth season was influenced separately. The K+ and Na+ ratios were also significantly increased, as were the salinity symptoms index and bunch yield per vine and quality. Rootstock 1103 Paulson improved photosynthetic pigments, K+ accumulation, Na+ uptake, and cell membrane damage in “superior seedless” vines compared to other rootstocks, according to the study results. As determined in the arid regions of northwestern Egypt, the 1103 Paulson can mitigate salinity issues when planting “superior seedless” vines on sandy soil.

Sequence stratigraphy and distribution of organic-rich Lower Cretaceous mixed clastic-carbonate strata in Matruh Basin, northwestern Egypt: Constrains on the Tethyan sea level changes, palaeoclimate, and tectonics

Integrated palynological, lithological, and geophysical analyses of the Lower Cretaceous (upper Hauterivian-Aptian) in Matruh Basin enabled conducting a high-resolution sequence stratigraphic analysis. Fluctuations of the continental/marine palynomorphs ratio reflect changes in the Tethyan 3rd order sea levels and are mirrored by eminent vertical changes in the spontaneous potential and the lithofacies. These are used with abundance of the marine phytoplanktons and opaque/translucent phytoclasts ratio to identify three 3rd order (SQ1: 132.4–120.8 Ma, SQ2: 120.8–115.2 Ma, and SQ3: 115.2–113 Ma) and seven 4th order genetic sequences and to study the impact of the allogenic and autogenic processes on their deposition.Deposition of the deltaic clastic systems tracts of the lower-middle Alam El Bueib (late Hauterivian-early Barremian) and Dahab (late Aptian) formations reflect the interaction between the regional humid climate and the Tethyan 3rd order sea levels, which superimposed the Tethyan 2nd order sea level. Interferences of minor regional tectonics were also important. The argillaceous deposits possess large amounts of terrestrial organic matter of low hydrogen index (HI: 185.8–211.5 mg HC/g TOC) indicating gas organic facies. These deposits show relatively high organic richness (1.81–2.50 TOC wt %) due to relatively low sediment dilution and water circulation (i.e. suboxic-anoxic conditions) and high primary productivity due to high riverine nutrient inputs.Deposition of the inner-middle shelf clastic-carbonate systems tracts of the upper Alam El Bueib and Alamein formations (latest Barremian-middle Aptian) reflects the interaction between the climatically induced low terrigenous influx and carbonate sedimentation due to shift to relatively dry climate, changes in the Tethyan 3rd order sea levels, and the middle Aptian regional minor uplift. These systems tracts show relatively large amounts of terrestrial organic matter, a notable marine organic matter signature, and intermediate HI (283.1–239.0 mg HC/g TOC) indicating gas/oil organic facies. The shales and siltstones are relatively organic richer (1.88–2.28 TOC wt %) than the pure and the argillaceous dolostones (1.46–1.94 TOC wt %). This organic richness is related to combined low sedimentation rates, low water circulation (i.e. dysoxic-suboxic to suboxic-anoxic conditions), and relatively high primary productivity.Overall, the Tethyan sea level changes, regional climate, and regional tectonics played a major role in the deposition of the organic-rich syn-rift Lower Cretaceous deposits in Matruh Basin.

GIS-based evaluation and statistical determination of groundwater geochemistry for potential irrigation use in El Moghra, Egypt

The El Moghra area is located in northwestern Egypt in the Western Desert. It is classified as the first priority of the national project to reclaim 1.50 million feddan of Egypt's desert lands. Groundwater quality assessment of the El Moghra aquifer is essential because irrigation water requirements in the El Moghra area depend solely on groundwater. A geochemistry analysis was conducted for 230,000 feddans from forty-six groundwater samples collected during the drilling process of deep wells in year 2018 and 2019. Our study's main objective is to determine whether the groundwater in the El Moghra aquifer is suitable for irrigation use. ArcGIS was used to prepare the geospatial distribution maps of major elements. Hydrochemical characteristics and groundwater types were identified from descriptive analyses of groundwater samples. Multivariate statistical analysis was run using SPSS; correlation coefficients were first determined; then, a correlation matrix was generated. Principal component analysis was performed and a covariance matrix with varimax rotation was produced. Results revealed the alkalinity and the high salinity of groundwater in the project study area. Most of the samples had a total hardness greater than 300 mg/l. Sodium chloride (Na-Cl) is the dominant type for groundwater samples. The mechanism controlling groundwater chemistry depends on rock weathering. Principal component analysis results showed that two eigenvectors among ten have a 72.86% contribution to the cumulative variance. The higher TDS values (14,008 mg/l) confirm the ions release when the upward groundwater flow from the lower Nubian Sandstone aquifer system to the upper quaternary aquifer occurs. Additionally, the geospatial maps of ion distribution showed that the frequent release of minerals happens in the northwestern part of the project study area: the eastern Qattara Depression. A perfect correlation between sodium and chloride distributions was obtained, and it is identical to the electrical conductivity distribution as well. Our study recommends very salt-tolerant crops as canola, barley, quinoa, and jojoba to be planted in the project area. Drought-tolerant crops as Barbary fig and Jatropha are also recommended. Applying irrigation water frequently with short intervals between irrigations to avoid soil drying and surface clusters' formation, as well as enhance leeching of salts away from the root systems, is essential.

Diversity and characterization of culturable haloalkaliphilic bacteria from two distinct hypersaline lakes in northern Egypt

Soda lakes characterized by salinity and elevated pH, these lakes represent a vast reservoir of novel microbial diversity of potential applications. In this article, two distinct salt lakes in northwestern Egypt were explored for the diversity of cultivable aerobic haloalkaliphilic bacteria. Physicochemical analyses revealed that samples possessed the characteristic features of alkaline hypersaline lakes (high pH, high Na+, and Cl− content with low Mg+2). The phenotypic characterization showed great diversification between members of the same genus. They were characterized phenotypically based on their cell and colony morphology, production of extra-cellular enzymes, some metabolic activities and antibiogram profile. Phylogenetic analysis was performed using 16S rRNA sequence. All strains were haloalkaliphilic belonging to phylum Firmicutes. They were affiliated to the genera Alkalibacillus, Salinicoccus, Gracilibacillus, Thalassobacillus, Halobacillus, Staphylococcus, and Bacillus. Surprisingly, Thalassobacillus species were only isolated from the sediment of Marsa-Matrouh lake (MML), while members of the genera Alkalibacillus, Salinicoccus and Staphylococcus were isolated from the sediment of Al-Hamra lake (AHL). Members of the genus Gracilibacillus were among the common community of the two lakes.

Morphometric and molecular differentiation between Egyptian Stellagama stellio vulgaris and S. stellio salehi (Reptilia: Agamidae)

From the seven recognised subspecies of Stellagama stellio, S. s. vulgaris is found in northwestern Egypt and S. stellio salehi in the south Sinai and are known to be very similar. A Principal Component Analysis was carried out for 14 morphometric fea­tures, PCA1 accounted for a little cumulative variation (87.03%) between the two subspecies with a strong canonical correlation (r = 0.999). PCA2 accounted for a high cumulative variation (98.04%) with a strong canonical correlation (r = 0.985) and head height (HH) was the only major parameter for the significant difference. Within 398 sites of 16S rRNA gene sequenced, 6 base substitutions were recorded between S. s. vulgaris and S. s. salehi and the pairwise genetic divergence was calculated as 1.5%, which is comparable to that found between some other conspecific agamids. Neither the morphometric nor the molecular data support the distinction of two different subspecies. No genetic difference was found between S. s. salehi and S. s. brachydactyla which occurs from northern Sinai over Jordan to Saudi Arabia.

Assessment and Spatial Analysis of Sensitivity to Desertification in Wadi El Natrun, Northwestern Egypt using MEDLAUS model

Land degradation is a global environmental issue, given the various negative impact on socio-economic and ecological implications. It leads to reduced production capacity in addition to soil erosion, physical /chemical /biological /economic land deterioration, and long-term loss (or degradation) of vegetation. When a severe deterioration in drought areas called the process of desertification i.e. arid, dry sub-humid and semi-arid areas. Desertification processes reduces the productivity of the soil and as a result effect on food stocks. The main objective of this study is integrating remote sensing data and a geographic information system (GIS) to evaluate the environmental sensitivity for desertification in Wadi El Natrun, Egypt based on the Mediterranean Desertification and Land Use (MEDALUS) approach. The collected soil data; from description of represented soil profiles and analysis of soil samples, in addition to climate, plant cover, and management data were considered for assessing the sensitivity of desertification. The obtained results showed that 10.4 % of Wadi El Natrun area is considered severe sensitivity to desertification as a result of alkalinity and salinity, while the moderately sensitive area occupies approximately 10.93 % of the study area. The low sensitive one exhibits 76.3 %. This area is described by high soil quality because of the study area is one of the new development areas which were not affected by the factors of desertification. It can be concluded that the desert extension of El-Beheira Governorate (i.e. Wadi El Rayan) is one of the areas that possess valuable land resources which should be considered for future land reclamation projects. Similar international studies are recommended to be achieved with the use of multi-criteria GIS modeling (i.e. MEDALUS) which considered all relevant factors in the form of thematic layers for easier implementation and assessments. Present study represents one of the initial attempts to use the MEDALUS model for desertification assessment in the desert extension of El-Beheira Governorate.

Palynostratigraphy and paleoecology of a Lower Cretaceous (upper Barremian–lower Aptian) succession in the Shushan Basin, northwestern Egypt: inferences on intra- and inter-basinal correlations

Recent national and international demand for additional resources of the fossil fuel resulted in extensive hydrocarbon exploration activities in Egypt to further explore possible petroliferous rock units that were conventionally deemed as barren or having non- commercial reserves such as the Alam El Bueib Formation. This increased the stress to enrich the lithological correlation of this formation across the north Western Desert to better understand its regional lithological characteristics and thus its potential regional reservoir/source rock quality. Palynostratigraphic analysis of Lower Cretaceous successions in the Tut-1X and Amoun-1X wells in the Shushan Basin, north Western Desert enabled the recognition of the upper Alam El Bueib Formation in both wells, in contrast to a previous study, which suggested non-deposition of this formation in the Amoun-1X well. This highlights the important role of the palynology as a key stratigraphic tool, which helped effectively in recognising this problematic monotone clastic formation, where other marine microfossils are lacking. This also shows that recognition of this formation based on lithological criteria only was impractical and misleading. Marker terrestrial and marine palynomorph taxa recovered from the upper Alam El Bueib Formation enabled dating it as late Barremian– early Aptian and were used to identify two palynological biozones that can be traced out regionally across the Shushan, Matruh, and other nearby basins. These biozones are the early Aptian Murospora florida – Afropollis operculatus – Pseudoceratium securigerum Assemblage Zone and the late Barremian Stellatopollis barghoornii – Pseudoceratium anaphrissum– Cyclonephelium vannophorum Assemblage Zone. An undifferentiated interval was recorded just below the upper Barremian strata in the Tut-1X well due to very low palynomorph recovery and absence of marker forms. Composition of terrestrial and marine palynomorph assemblages suggests the upper Alam El Bueib Formation was deposited in fluviodeltaic to proximal inner shelf settings. The Alam El Bueib Formation shows notable regional variations in thickness and considerable lateral and verti- cal changes in lithology due to local tectonics and relative difference in its depositional settings in the Shushan and Matruh basins. Regionally, the Alam El Bueib Formation shows dual reservoir/source rock characteristics, where thick and poorly fossiliferous sandstone units act as reservoir rocks, while moderately fossiliferous finer clastics and carbonates already acted as intraformational source rock intervals in some parts of the Shushan and Matruh basins.

Organic geochemical, palynofacies, and petrographic analyses examining the hydrocarbon potential of the Kharita Formation (Albian) in the Matruh Basin, northwestern Egypt

A recent study of selected samples from the Cretaceous (Albian) Kharita Formation of Egypt revealed very good to excellent source rock (SR) potential for six intraformational, organic-rich intervals. This work investigates the SR potential of the entire Kharita Formation across the Matruh Basin, using samples from two wells: the Abu Tunis 1X well from the central part of the basin, and the Siqeifa 1X well drilled on the eastern margin of the basin. More strongly reducing conditions were developed in the centre of the basin, and resulted in the deposition of more organic-rich shales by comparison to the less reducing conditions that prevailed on the eastern basin margin, where the shales contain less organic matter. Deltaic intraformational shales and carbonates in the Kharita Formation of Abu Tunis 1X constitute a significant 120 m net of the potential SR. The lower Kharita Formation contains 34 m net shale SR of good to very good/excellent organic richness, yielding values of 1.14–11.59 wt % total organic carbon (TOC). The organic matter has low Hydrogen Index (HI) values (184–389 mg HC/g TOC) and amorphous organic matter (AOM) and relatively high non-opaque phytoclast frequencies indicating mainly gas/oil-prone organofacies (kerogen Types III/II). The upper Kharita is rather important, containing 86 m net shale/carbonate SR that has fair to good organic richness (0.8–1.8 wt % TOC), and lower HI (126–250 mg HC/g TOC), a dominance of non-opaque phytoclasts, and subordinate AOM frequencies, which together indicate gas/oil-prone organofacies (kerogen III/II). In the Siqeifa 1X well, Kharita deltaic intraformational shales and shaley dolostones comprise 80 m net SR, which has mainly fair to good to less very good organic richness (0.8–2.1 wt % TOC), whilst low HI (93–220 mg HC/g TOC), dominance of non-opaque phytoclasts and subordinate AOM indicate gas-prone organofacies (kerogen Type III). A relative upward increase in deposition of lignite and coaly carbonaceous material supports a gas-prone organofacies. Whilst thermal maturity indices only point to immature to early mature (pre- to early oil-window) SRs in both the Abu Tunis 1X and Siqeifa 1X wells, hydrocarbon exploration focussing on this potential source rock may be justified in areas to the southeast of the Matruh Basin, where modelling indicates this unit may have reached the late mature oil- to main gas-generation windows.

Cretaceous (Hauterivian–Cenomanian) palaeoceanographic conditions in southeastern Tethys (Matruh Basin, Egypt): Implications for the Cretaceous climate of northeastern Gondwana

Quantitative palynological, sedimentological, and geophysical data analyses of the Cretaceous Abu Tunis 1X well from the Matruh Basin, northwestern Egypt indicate deposition of four major alternating regressive–transgressive successions. Sedimentation was largely affected by the Tethyan 2nd order sea level changes, with minor overprints by regional tectonics. The Lower Cretaceous part of the succession shows regressive sequences of deltafront to delta-top (upper Hauterivian–lowermost upper Barremian), delta channel (upper Aptian–middle Albian), and distal deltaic (upper Albian) settings that were interrupted by transgressive inner–proximal middle shelf deposits (uppermost Barremian–middle Aptian). These sediment packages correspond to Tethyan sea level fall from the late Hauterivian to late Barremian, and to the early–middle Aptian long-term sea level high stand. The Tethyan late Aptian–middle Albian long-term (2nd order) sea level rise was masked by regional late Aptian–Albian uplift, which affected deposition of the later regressive sequence. The Cenomanian shows a change in depositional setting from a proximal inner shelf (lower Cenomanian) to a middle shelf setting (middle–upper Cenomanian), corresponding to the Tethyan long-term latest early–late Cenomanian sea level rise.We demonstrate that northeastern Gondwana (Egypt) experienced different climatic conditions from other parts of the Northern Gondwana Phytogeographic Province. The climate in Egypt shifted from less warm and more humid conditions of the Hauterivian–early Barremian to a warmer and drier climate during the late Barremian–middle Aptian, although never becoming as dry as western Northern Gondwana. Warmer and more humid conditions were reestablished during the late Aptian and became even more accentuated during the Albian–Cenomanian, in contrast to the warm and much drier climate of Northern Gondwana at that time. Turonian climatic conditions may have been less humid as a result of the breakup of the Western Gondwanan supercontinent and the northeasterly drift of the African continent. The climatic conditions experienced in northeastern Gondwana developed through the early-mid Cretaceous as a result of changes in palaeolatitudinal position, variations in sea level, and shifts in the Intertropical Convergence Zone, which drove fluctuations between periods of warm humid and warm dry conditions.

EFFECT OF WASTEWATER AND FERTILIZER APPLICATION ON CALCAREOUS SOIL AND FOOD CROPS IN BORG EL ARAB – EGYPT

This paper summarizes the available information on the pollution of groundwater and irrigation canals from anthropogenic sources (sewage effluences and industrial waste water, and intensive fertilization) in northwestern Egypt Borg El Arab that leading to contamination of the soil-plant-animal. Excessive applications of fertilizers to field and vegetable crops lead to nitrate and phosphate contamination of groundwater and irrigation canals. In certain situations, nitrates exceed the dangerous level of 10 mg N/L. Industrial effluents, released without anytreatment to sewage drains, contain potentially toxic elements with a concentrations that are several fold higherthan those in domestic sewage water and exceed the maximum permissible limits for their disposal onto agricultural lands. The mean concentrations of Pb, Co, Cd and Ni in sewage water were, respectively 21,133, 700, and 2200 times higher than those in artesian water. The recommendation possible mitigation options for water pollution. There is an urgent need to effectively enforce regulations for the release of industrial effluents pertaining to primary, secondary and tertiary treatments. Educating farmers and public at large about the consequences of non-overkill Nitrogen fertilizer, pumping out shallow polluted water for drinking and domestic purposes, depleting groundwater resources, etc., is desirable