Wadi Halfa Research Articles

Relationship between petrography and geomechanical properties of the sandstone: A case study from Wadi Halfa, North Sudan

Relationship between petrography and geomechanical properties of the sandstone: A case study from Wadi Halfa, North Sudan

A Comparison of the Reproductive Patterns of Oreochromis niloticus from Two Distinct Locations: Wadi Halfa, Sudan, and Aswan, Egypt

A Comparison of the Reproductive Patterns of Oreochromis niloticus from Two Distinct Locations: Wadi Halfa, Sudan, and Aswan, Egypt

Daily and annual performance analyses of the BIPV/T system in typical cities of Sudan

• A mathematical model of the BIPV/T system is established. • The energy-saving potential of the system for different regions of Sudan is analyzed. • Wadi Halfa has the highest total annual electrical power output. • The BIPV/T HVAC system satisfies a high percentage of the heating needs of Sudan. In this paper, a numerical study is carried out to investigate the performance of a coupled BIPV/T-AHU system in Sudan. A mathematical model was utilized, Matlab Simulink was used to do simulation. Results showed good agreement with experimental data from the literature. The problem studied in this paper is reducing the energy required for heating in winter (preheating BIPV/T) and avoiding the high photovoltaic cell temperature in summer. We compare the energy consumption with and without BIPV/T-AHU in different cities in Sudan. The results showed that utilizing the exhaust air to cool the photovoltaic cell could reduce the PV/T cell temperature in the range ( 9 − 12 ) ∘ C , which can increase the electrical power output in a range of ( 12 − 21.44 ) W / m 2 . In winter, utilization of the preheating BIPV/T system can decrease the heating load in Wadi Halfa in the range of ( 6 − 107.1 % ) . Damazein does not need a high heating power in the daytime for the air conditioning system depending on the local climate, so the heat energy produced by the system can be used for drying, desiccant cooling, or heating water, with increasing the electric power produced by cooling PV/T cells. The results indicated a great possibility to use the BIPV / T system under the studied conditions, in addition, this study provides important information for the application of the BIPV / T system in these areas.

Wadi Halfa average monthly wind speeds in knots, 2006-2016

Wadi Halfa average monthly wind speeds in knots, 2006-2016

Modelling and analysis of an 80-MW parabolic trough concentrated solar power plant in Sudan

Abstract Concentrated solar power plants can play a significant role in alleviating Sudan’s energy crisis. These plants can be established and implemented in Sudan, as their potential is considerably high due to the climate conditions in Sudan. This study investigates the design of a parabolic trough concentrated solar power plant in Sudan and analyzes its technical and economic feasibility. The simulation of the plant’s model used System Advisor Model (SAM) software. To determine the best location for the construction of the plant, data from 15 cities in Sudan were compared with each other based on their solar radiation and land properties. Wadi Halfa, a city in the northern region of Sudan, was chosen as the location due to its good topographical properties and climate conditions. The results show that the proposed plant can generate 281.145 GWh of electricity annually with a capacity factor of 40.1% and an overall efficiency of 15%. Additionally, a simple cost analysis of the plant indicates a levelized cost of electricity of 0.155 $/kWh. As the study results are consistent with the characteristics of similar plants, the proposed plant is considered technically and economically feasible under the conditions at its location.

Remote sensing based water resources and agriculture spatial indicators system

Integrated automated application for Water Resources and Agriculture Spatial Indicators System (WRASIS) using remote sensing Data was developed to monitor and assess different developments projects in agriculture field. This system is based on the analysis of remotely sensed time series data of (Agriculture Moderate Resolution Imaging Spectra-radiometer MODIS NDVI – Rain-Fall Estimate RFE 2.0). Three agriculture projects located in Sudan; White Nile sub-basin “Assalaya Project (AAP)”, Wadi Halfa (WHAP) at Atbara Basin, and Ginude agriculture project at Blue Nile sub-basin are taken for pilot study using this newly developed system which is includes GIS-based procedures for computing water and agriculture spatial indicators. The data used is derived from satellite images product at different spatial and temporal resolution. These products were extracted automatically and stored with their analyses and results in special database, which could be used with easily manner to obtain and compute indicators and perform statistical data analyses. WRASIS has specific tools to analyze and display data in a tabular form, classify maps and display statistical charts as well. WRASIS runs in three main phases; data-base preparation, model calculation (data analysis), and finally system tools and outputs. The outputs are either basic indicators (one indicator for one-time step) or advanced indicators. Many satellite images with diverse products and resolutions could be added to the system in data preparing phase for other applications at any area. In the present study and from monitoring and assessments of the three agriculture projects, the effect of supplementary irrigation is clear.

Is this the right time for Sudan to replace diesel-powered generator systems with wind turbines?

Access to electricity is vital in rural regions of Africa. There is substantial potential to utilise wind energy, yet investment in renewable energy projects is trivial because it has been insufficiently endorsed. As a result, most people living in remote regions of Africa rely entirely on diesel-powered generators, which expel pollutants in substantial amounts. These adversely affect the health of people and the environment. Sudan – one of Africa's largest countries – has a range of resources from which renewable energy could be generated, including favourable wind power generating conditions. This paper represents the first effort in literature to use a strategic perspective to explore how viable wind energy systems are in Sudan. It reports a study using the Hybrid Optimization Model for Electric Renewables (HOMER) across 21 diverse sites in Sudan. It identifies the optimal wind turbine system and best locations and analyses the costs involved and how much pollution could be prevented by implementing wind farms instead of diesel systems. The results establish that the optimal type of wind turbine across the investigated locations is the Enercon E−138 EP3. Wind farm use is expected to avoid almost 49 million kg/year of pollutants and reduce energy cost by US$0.91317/kWh. The optimal sites for utilising wind energy were Wawa, Dongola, Karima, Wadi Halfa and Al-Goled in order of suitability and their low costs of electricity and high wind speed records. Wind turbine pricing is predicted to reduce over time, so the study varied the cost of wind turbines to understand the impact on project economics. A reduction in wind turbine costs by 10 % lowered energy cost to between US$0.03681/kWh and US$0.04052/kWh. A further 25 % price drop reduced the cost of energy to between US$0.03067/kWh and US$0.03376/kWh. This study reveals the significant potential of integrating renewable energy into the energy mix of Sudan and provides an essential reference for wind farms in the energy sector across other developing countries.

Petrography, Diagenesis and Paragenesis of Wadi Halfa Oolitic Ironstone Formation, North Sudan

Utilizing petrography, diagenesis and paragenesis are the major step to study the sediments of Wadi Halfa Oolitic Ironstone Formation for their origin and economic potential. Petrographical analysis of Wadi Halfa Oolitic Ironstone Formation were carried out depending on the investigation of six vertical lithofacies profiles from the region of Wadi Halfa. The petrographic classification of sandstone samples of Wadi Halfa Oolitic Ironstone Formation according to mineral composition (quartz, lithic fragments, and feldspars) are classified as quartzarenite 66.7%, sub lithic arenite 20.9% and subarkose 12.5%. The provenance of the sandstone revealed that all sample were derived mainly from interior stable craton. The stable craton offered good environments for detrital constitution to be recycled and transported for relatively long-distance. The present study adopted an intergranular pressure solution (IGV) diagram for IGV values more than 50 percent for all studied samples indicating that more of their original porosity has been destroyed cementation rather than by compaction processes for most samples.

Determination of the optimal solar photovoltaic (PV) system for Sudan

Electricity access in Africa is a major challenge in rural areas. Despite considerable potential for the use of solar energy, investments in renewable energy projects are minimal due to poor promotion of solar energy. As a result, many people still rely on private diesel generators, which release significant levels of pollutants, and have negative effects on both humans and the environment. Situated in the sunbelt, Sudan is one of the largest countries in Africa endowed with an extremely high solar irradiation potential. However, no work has been done in the literature with a strategic context to study specifically the feasibility of renewable energy systems in Sudan despite the abundance of solar resource. The aim of this study was to utilize Hybrid Optimization Model for Electric Renewables (HOMER) to identify the optimal solar photovoltaic (PV) system for Sudan’s conditions, identify the best locations, and analyze the costs and the pollution that might be avoided by employing a PV system in place of a diesel system. HOMER simulation results demonstrated that the optimal type of PV for Sudan is the Studer VarioTrack VT-65 with Generic PV. The utilization of a solar PV system will avoid the production of approximately 27 million kg/year of pollutants and will reduce the cost of energy to USD$ 0.08746/kWh. The optimal locations found in Sudan for utilizing solar energy were Wawa, followed by Kutum, Wadi Halfa, Dongola and Al-Goled due to their low costs of electricity, high clearness index and high levels of solar radiation. Given the recent rapid decrease in PV pricing and predictions for continued reductions, the costs of PV were varied to deliver an understanding on the impact of PV costs on the project economics. Reducing the PV costs by 25% has a significant impact; the cost of energy produced reduces in the range of USD$ 0.06697/kWh and USD$ 0.06808/kWh, while a reduction in PV costs of 50% further reduces the cost of energy, ranging between USD$ 0.05273/kWh and USD$ 0.05361/kWh in the top five locations in Sudan. The output of this study is projected to raising the potentiality awareness of renewable energy in Sudan and delivering a valuable reference regarding the optimal utilization of solar PV system in energy sector.

Barite Concretions in Wadi Halfa Oolitic Ironstone Formation, North Sudan

During our examination of the outcrops of the sedimentary formations in northern Sudan, we found discoidal-shape grains of the heavy mineral, barite in a sandstone of the Wadi Halfa Oolitic Ironstone Formation, which was recorded by all the earlier workers as a reworked sandstone. Petrography-wise, the framework of the sandstone consists of very angular to angular quartz grains, in which monocrystalline grains dominate over polycrystalline grains. Barite is the main cementing material of this sandstone, which occurs as concretions. Barite concretions indicate that more of the original porosity has been destroyed by cementation rather than by compaction processes with the inter-granular porosity being reduced mainly due to cementation. The origin of these concretions, as a cementing material in the sandstone, is ascribed to the reaction of Ba with some soluble sulfate to form the extremely insoluble heavy barite that appears as rounded concretions. The sulfur of the sulfate may be from the hydrothermal fluids related to submarine volcanism and/or biogeochemical processes. The deposition of these concretions might have taken place not long after the formation of the sandstone. The source of the barium, however, remains an unsolved problem. Further work is needed to interpret the origin and occurrence of these concretions along the region of Wadi Halfa.

Adil El-Tayar: renowned NHS transplant surgeon who died from covid-19

Photo credit: Abbas Ghazanfar On 25 March Adil El-Tayar, a renowned organ transplantation specialist, became the first working NHS surgeon to die from covid-19 in hospital in the UK. A healthy and active 64 year old, he is thought to have contracted the virus at a hospital in the Midlands, where he worked during the week. He cared deeply about the NHS, an institution he had spent his life serving. Born in Atbara, Sudan, a railway city on the Nile, El-Tayar was the eldest son of a government clerk and a housewife. He had 11 siblings. A close knit community, Atbara had been built by the British to serve the railway line between Port Sudan on the Red Sea coast and the Wadi Halfa in the north. It was here that the first Sudanese labour movement started in 1948. El-Tayar attended the local school and was a diligent student. During his childhood, one of his brothers, Osman, became ill and died without suitable medical treatment. Although El-Tayar rarely spoke about his brother’s death, he named his …

Contribution of Research Projects and Environmental Impact Assessment Studies to Fauna Biodiversity in Sudan

Eighteen species of ants were recorded for the first time in Sudan including Lepisiota omeri n. sp.; Parasitological surveys of freshwater fishes of the Sudan during 2006 to 2014revealed the presence of four genera of parasitic crustacean; 42 species belonging to 19 monogenean genera parasites were collected from 26 fish species. Out of these the following five species are new to science (n. sp.): Quadriacanthus fornicatus, Q. pravus, Q. zuheiri, Q. mandibulatus and Dogielius senegalensis. Seven new records to the Sudan helminthes were added. These are: two cestodes (Monobothrioides tchadensis and Proteocephalus glanduligerus); one digenetic (Clinostomum complanatum larva) and three nematodes (Capillaria sp., Spinitectus sp. and Philometra bagri. Recording of Barsonella lafoni as a n. sp. of Proteocephalidean (Cestoda) from Clarias catfishes was based on material from Tarkana Lake (Kenya) and Wadi Halfa, Lake Nubia, Sudan.

English

Wadi Halfa Oolitic Ironstone Formation (WHOIF) covers large areas around Wadi Halfa border town in Northern Sudan. The detrital framework grains of sandstone of WHOIF are composed of sub-angular to sub-rounded quartz grains followed by feldspars, lithic fragments, micas and heavy minerals. The dominant cementing materials are iron oxides, carbonate cement, and some clay minerals. Twelve block samples were carefully selected and collected from six sites to represent different parts of vertical lithofacies sections of the studied formation. The petrographical characteristics of the specimens were first studied and the specimens were then subjected to laboratory tests to determine some of their basic physical and engineering properties. The physical tests constituted unit weight, specific gravity and water absorption. The measured engineering properties included uniaxial compressive strength (UCS) and ultra-sonic pulse velocity (UPV). The UCS and UPV were measured for specimens parallel and perpendicular to the bedding planes of the studied samples. The geotechnical study shows that the UCS values of WHOIF generally range from strong 83.7 MPa to very strong 153.7 MPa for perpendicular direction to bedding planes. Very good statistical correlation coefficient was developed between UCS and UPV. Good correlation was obtained between water absorption, porosity and UPV. These relations indicated that a decrease in void ratio and porosity resulted in an increase in UCS and UPV. An increase in water absorption of sandstone yielded a decrease in ultrasonic pulse velocity and uniaxial compressive strength. Key words: Wadi Halfa Oolitic ironstone formation, lithofacies, uniaxial compressive strength, ultrasonic pulse velocity.

Determination of some heavy metals content in the body of two popular fish species O.niloticus and L. niloticus, in lake Nubia, Wadi Halfa, Sudan

Determination of some heavy metals content in the body of two popular fish species O.niloticus and L. niloticus, in lake Nubia, Wadi Halfa, Sudan

The Land of the š3sw (Nomads) of yhw3 at Soleb

The temple of Amun-Ra at Soleb, constructed in Kush (Nubia) during the reign of Pharaoh Amenhotep III in the 18th Dynasty and “rediscovered” in 1813 by Burckhardt, is famous for its status as the southernmost temple and its scenes of the Heb-Sed Festival of Amenhotep III. Located about 185 kilometers southwest of Wadi Halfa, the partially preserved Soleb temple of Amenhotep III on the west bank of the Nile, just south of the Third Cataract, can be difficult to access. According to the building inscription of Amenhotep III from Thebes, the Soleb temple was named Khaemmaat and was dedicated to Amun-Ra and to Amenhotep III as a deity. A New Kingdom cemetery was nearby to the west, and subsequent rulers Akhenaten, Ay, and Tutankhamun also had modifications made to the temple. Even as early as 1829, the expedition of Major Felix which visited the site recognized that the prisoner inscriptions on visible columns were commemorating the victories of Amenhotep III, but after the centuries, Sector IV of the hypostyle hall was in ruins, toppled, and partly covered by sand. However, following the 1957–1963 excavation expedition led by Michela Schiff Giorgini, the uncovered remains were analyzed and reconstructed with the available pieces which had been discovered and identified. The columns of the hypostyle hall, decorated with bound prisoner reliefs and the names of peoples or places rendered in Egyptian hieroglyphs, are of significant geographical and historical importance.

Inverted topographic features, now submerged beneath the water of Lake Nasser, document a morphostratigraphic sequence of high-amplitude late-Pleistocene climate oscillation in Egyptian Nubia

The Nile Valley between the Second Cataract at Wadi Halfa and the First Cataract at Aswan has been inundated behind two dams – the Aswan Dam, first built in 1902, and the High Dam (Sa'ad el A'ali), that blocked the flow of the Nile in 1964. The anticipated loss of archeological monuments in Lake Nasser, the reservoir behind the High Dam, initiated an international campaign to protect, move, or at least document as many of those monuments as possible.The UNESCO Campaign to Salvage the Monuments of Nubia included two projects that undertook to record the prehistoric archeology of the reservoir area; each of those projects engaged geologists to help place archeological sites in rigorous stratigraphic contexts. Thus, the Nile Valley between Wadi Halfa and Aswan was the site of an intensive investigation of late-Cenozoic geologic history.In this paper we summarize the principal stratigraphic elements of the suite of sediments and landforms that characterize the late-Cenozoic geology of Egyptian Nubia. Those elements include:1.Early Nile Gravel (ENG), a Nile flood-plain gravel deposited while humans were manufacturing Acheulean artifacts in the Nile Valley.2.Wadi Conglomerate (WCGL), a wadi-floor gravel topographically inverted to form sinuous ridges in the time after deposition of ENG.Because of the deep incision of the Nile Valley and immediately adjacent tributary wadis, the terrain close to the Nile, within the Reservoir area, preserves multiple generations of wadi inversion, a complex morphostratigraphic sequence not described from other areas in Egypt. The oldest body of WCGL was deposited at the same time as the ENG was accumulating.3.Late Nile Sediments (LNS), a section of younger (∼27,000-5000 14C yrs BP) sediment representing both local components and Nile-deposited components, that enclose a rich inventory of prehistoric cultures younger than Acheulean.Although examples of WCGL can be studied at locations remote from the Aswan Reservoir, most outcrops of ENG, WCGL, and LNS described in the field in Egyptian Nubia are now submerged under the water of the Reservoir.

In Situ: The Contraindications of World Heritage

In light of contemporary discussions on the preservation of world heritage, this article considers the cultural costs of archaeological reconstruction and site development. Popular, political and scholarly discussions often presume that the preservation of material heritage functions as a shining knight battling the dark forces of destruction. Yet far from purely constructive, sites we think of as authentically historical are often reconstructions. Their resurrection often depends on the erasure of intermediary traditions and the displacement of local communities, making them highly contested political symbols. As political frameworks shift, the tension between preservation and destruction established through this process often serves as propaganda. Examining the effects of archaeological site reconstruction on local populations at Tadmur (Palmyra, Syria); Geyre (Aphrodisias, Turkey); Wadi Halfa (Abu Simbel, Egypt and Sudan); and Bamiyan (Afghanistan), this article examines the dangers in the instrumentalization of world heritage as a rhetoric of ownership that pits civilization against barbarism without considering the complex costs that accrue as we access the past. The past can only retain value for the future if it does not come at the cost of the living present.

Taphonomy of old archaeofaunal collections: New site-formation and subsistence data for the Late Paleolithic Nile Valley

Archaeofaunal remains play an important role in the studies of Late Pleistocene human adaptations in Africa. Salvage excavations and surveys along the Nile Valley, in the Kom Ombo Plain (Upper Egypt) and opposite Wadi Halfa (northern Sudan), respectively conducted in the 1960s by Yale and the University of Colorado produced several Late Paleolithic (ca. 22.5–14.5 years BP) faunal assemblages which have never been published. Here I present a comprehensive taphonomic and zooarchaeological analysis of the faunal assemblages, with the aim of, first, understanding their integrity through identifying the depositional, post-depositional and collection biases and, second, characterizing the latest Pleistocene animal economy in the Nile Valley. The faunal assemblages come from both surveys and controlled excavations and in most cases the collections appeared to have been fully retained. The excavated remains were deposited in thin horizons representing small camps, associated with diverse lithic assemblages and sometimes hearth features. In one case the fauna originates from a large cemetery (the 6B36 site, opposite Wadi Halfa). Taphonomic criteria indicate that the faunas are anthropogenic and attest to consumption of predominantly medium and large ungulates as well as hippopotamus. The preservation of the material is variable and was chiefly affected by dispersal processes and the pace of burial. The assemblages' characteristics and their context suggest non-intensified animal exploitation and consequently low site-occupation intensity in the Nile Valley during the latest Pleistocene.

Diet reconstruction through stable isotope analysis of ancient mummified soft tissues from Kulubnarti (Sudanese Nubia)

Carbon and nitrogen stable isotope values were measured in tissues of Nubian mummies from two Christian cemeteries (AD 550–800) located on the island of Kulubnarti about 130km south of Wadi Halfa in Sudanese Nubia. Protein suitable for isotopic analysis for dietary reconstruction was extracted from soft tissue samples of 90 naturally mummified individuals (47 adults, 42 immatures and one of unknown age at death). The isotopic data indicated that the diet of these Nubian populations included a mix of C3 and C4 plants (predominantly C3) in addition to a relatively small contribution of animal protein from terrestrial sources and no aquatic protein sources. A significant difference was found regarding the δ13C values between the two cemeteries which may indicate a diet enriched in 13C (more C4 plants) in the individuals buried in the Kulubnarti R cemetery. No significant difference in the δ15N values was found between the two cemeteries indicating nearly the same proportion of animal protein in the diets of the two population samples. Significant differences were found between different soft tissues in the nitrogen isotopic signatures with meninges and periosteum being the most 15N-enriched tissues, followed by skin, while cartilage was the least 15N-enriched tissue. No significant differences were found in the δ13C values between different tissues. Although the δ13C and δ15N values from bone collagen of the same material showed significant differences between age groups, the soft tissue samples did not show any significant isotopic differences between age and sex categories. Moreover, comparing soft tissue with bone collagen results showed 15N-enrichment in the soft tissues, most probably as a result of physiological and fractionation differences between the collagen of the soft tissues and bone collagen.

Discovery of a New Style of Magnetite Mineralization, South of Wadi Halfa Town, Northern Sudan

Discovery of a New Style of Magnetite Mineralization, South of Wadi Halfa Town, Northern Sudan