Conference Presentations by Abdalla El Sheikh
Geological study has been done in the Hamisana area, which lies in the Red Sea
State -north east... more Geological study has been done in the Hamisana area, which lies in the Red Sea
State -north east of Sudan, bounded by Lat 20° N to 21° N and Long 34° E to 35°
E, and covered over most part by geological formation that belong to the Arabian
Nubian Shield (ANS).
The area is very characteristic in lithological, structural and tectonic setting but it
lies in desert and accessibility is very difficult, so there are not enough detailed
geological studies. Using remote sensing, geographical information system (GIS),
structural analysis, geochemical evaluation and geological field observations the
present study has managed to shed light on geological characteristics of the area.
Color composite, band ratio, color transform and principle component analysis
(PCA) were applied in Landsat ETM+ image to increase the discrimination
between various lithological units, and augmented with GIS enabled the
protection of a detailed geological map.
The area is dominated by the highly sheared meta-volcanogenic group of low
grade which is intruded by Syn to late ‐ and post‐Orogenic igneous intrusions in
addition to mafic –ultramafic rocks.
The structural analyses show that the Hamisana Shear Zone (HSZ) is a broad
deformation at shearing trending N-S. From field check points a structural map is
constructed where five phases of deformations are recognizable: D1 is foliation,
D2 is upright tide folding, D3 is the NE-SW folding, D4 is the open refolding in E-
W and D5 is the reactivation of the N-S shearing, these phases including in three
episodes.
Many types of discrimination diagrams were used in geochemical analysis to
determine tectonic setting and geochemical environments from these diagrams.
The ultra-basic rocks from the mantle sequence are mainly metamorphic
peridotite and mafic and ultra-mafic cumulated which are harzburgite and
dunite. Pillow lavas and sheeted dykes are Tholeiitic within MORB and back arc
basin basalt. Chromite in the area is podiform chromite. Post and syn-orogenic
granite from trace element analyses are within plate granites (WPG).
Papers by Abdalla El Sheikh
Geosciences and Engineering
This study aims at identifying target zones for groundwater exploration in basement terrains usin... more This study aims at identifying target zones for groundwater exploration in basement terrains using geological, geomorphological, and geoelectrical methods. The study area is located on the northwestern side of the Red Sea Hills in the western Hamissana area. It is part of the Arabian Nubian Shield (ANS), which dates to the Pan-African Era. The study area is covered by Precambrian basement rocks which are overlain by alluvial deposits. The climate in the region is arid. As a result, severe water shortage is experienced. The geological and geomorphological investigations were carried out to locate potential sites for groundwater prospecting. On this basis, three categories of groundwater potential zones were delineated as good, moderate, or poor. The electrical resistivity method using vertical electrical sounding (VES) technique was used to determine the vertical geological profile of the study area. The sequence was revealed to consist of four zones: a high-resistance unsaturated zo...
Geophysical investigation has been carried out to explore the groundwater occurrence in the area ... more Geophysical investigation has been carried out to explore the groundwater occurrence in the area between Wad Elhelew and Khashm El Girba towns, Kassala and Gedaref States, eastern Sudan. Vertical electrical sounding technique was applied using Schlumberger Array (configuration), with a maximum half separation AB/2 = 900 -1000 m. The study area covered by (177) points of vertical electrical sounding (VES) measurements distributed to cover the study area at the both sides of the River Atbara and Setit, (Figure 9). The VES points distributed to fill the gabs where there are no wells and to detect the boundary of the aquifers. Based on variations in apparent resistivity of various formations and sequences the study area was divided into three sectors; upstream area, Middle area and downstream area. Three geo-electrical sections constructed in the study area in E-W direction. From the data interpretation; the Aquifer zones in the study area seems to be wider upstream and gets narrower do...
Groundwater balance in the Khor Arbaat basin, Red Sea State, eastern Sudan
Hydrogeology Journal, Nov 3, 2009
... The groundwater recharge in the Khor Arbaat basin occurs either when the area is flooded by s... more ... The groundwater recharge in the Khor Arbaat basin occurs either when the area is flooded by surface water, or when groundwater flows through the upper gate, or when rainfall infiltrates directly in the area between the upper and the lower gates. Sir Alexander Gibb and ...
Open transactions on geosciences, Jun 30, 2014
ABSTRACT Groundwater represents the available source of fresh water in the northeastern part of K... more ABSTRACT Groundwater represents the available source of fresh water in the northeastern part of Khartoum State for drinking as well as for irrigation purposes. The objective of this study involves the assessment of the occurrence and potentiality of the groundwater in order to meet the increasing demand of water. The adopted methodology involves the digital processing of Landsat 8 OLI image and geophysical vertical electrical sounding (VES). VES data was processed and interpreted with the aid of IP2WIN computer Software. The outcome of the present study showed that the area is located in the transition zone between the basement and sedimentary terrains. The River Nile represents the main source of groundwater recharge from W and SW directions, with minor recharge source from the direct precipitations and seasonal valleys for the shallow groundwater aquifers. The depths to the basement vary from that basement exposed at the surface to more than 200m a.s.l. at the western part of the area. The very high resistivity values (>400 ohm/m) reflects the hard basement rocks, the high values (250-400 ohm/m) were interpreted as dry soils and gravels, while low resistivity values (<250 ohm/m) are related to sedimentary rocks. The conducted geo-electrical resistivity survey indicated that the basement exposed at the ground surface at the central part of the study area, while the considerable thickness of sedimentary rocks in the eastern and the western side of the area is preserved as a result of structural faulting. In term of sedimentary thickness and the recharge source, the western part of the area is considered the most potential zone for groundwater occurrence.
Arabian Journal of Geosciences, Aug 17, 2010
The River Gash Basin is filled by the Quaternary alluvial deposits, unconformably overlying the b... more The River Gash Basin is filled by the Quaternary alluvial deposits, unconformably overlying the basement rocks. The alluvial deposits are composed mainly of unconsolidated layers of gravel, sand, silt, and clays. The aquifer is unconfined and is laterally bounded by the impermeable Neogene clays. The methods used in this study include the carry out of pumping tests and the analysis of well inventory data in addition to the river discharge rates and other meteorological data. The average annual discharge of the River Gash is estimated to be 1,056×10 6 m 3 at El Gera gage station (upstream) and 587× 10 6 m 3 at Salam-Alikum gage station (downstream). The annual loss mounts up to 40% of the total discharge. The water loss is attributed to infiltration and evapotranspiration. The present study proofs that the hydraulic conductivity ranges from 36 to 105 m/day, whereas the transmissivity ranges from 328 to 1,677 m 2 /day. The monitoring of groundwater level measurements indicates that the water table rises during the rainy season by 9 m in the upstream and 6 m in the midstream areas. The storage capacity of the upper and middle parts of the River Gash Basin is calculated as 502×10 6 m 3 . The groundwater input reach 386.11×10 6 m 3 /year, while the groundwater output is calculated as 365.98×10 6 m 3 /year. The estimated difference between the input and output water quantities in the upper and middle parts of the River Gash Basin demonstrates a positive groundwater budget by about 20×10 6 m 3 /year
North Kordofan State represents the world’s main supplier of Gum Arabic in addition to considerab... more North Kordofan State represents the world’s main supplier of Gum Arabic in addition to considerable amount of livestock. Nevertheless, the area suffers from acute shortages of fresh water supply for both human and animal consumption. The overall objective of the present study is the investigation of groundwater occurrence through an integrated methodology incorporating remote sensing, lineament mapping, structural analysis and geophysical studies via electrical resistivity methods. The study area is located in semi-arid zone with annual average rainfalls range between 150 to 250 mm. Topographically, the area is flat with slight slope to the northeast. Wadi Almilk and its tributaries represent the main source of groundwater recharge in addition to the direct precipitations. The alluvial, fractured and weathered basement are the main yielding groundwater source. The area is a part of a basement terrain, where the structural setting represents the main controlling factor of the aquifer...
The beach and coastal plain of the Red Sea Region of northeastern Sudan have witnessed considerab... more The beach and coastal plain of the Red Sea Region of northeastern Sudan have witnessed considerable impact as a result of the growing population. Optimum design and construction of foundation in the coastal plain require detailed surveys of geomorphology and geological conditions combined with geotechnical investigations of soil and marine formations. The study area is about 60 km extends from Port-Sudan to Suakin harbor at the Red Sea coast of Sudan. The coastal plain of the Red Sea is underlain by Tertiary and Mesozoicsediments, overlying unconformably the basement rocks. The raised beach complex consists of marine and continental clastic deposits and reef limestone of Pleistocene and Recent ages overlying the Tertiary formation. The objectives of the current study are to carry out detailed investigation of the subsurface stratigraphy and weathering grade; modeling of the subsurface layering, and to determine the suitable layers for foundation construction. According to facies cla...
Applications of Remote Sensing and GIS in Geological Mapping, Mineral Prospecting and Groundwater Investigations in the Arabian-Nubian Shield: Cases from the Red Sea Hills of NE Sudan
The Geology of the Arabian-Nubian Shield, 2021
In the last decades Sudan became one of oil production countries. Extensive exploration works wer... more In the last decades Sudan became one of oil production countries. Extensive exploration works were conducted which depend largely on the acquisition of seismic data for detailed information about the subsurface geological structures and formations. During the exploration works, a considerable number of bad seismic lines were recorded, which affect the quality of seismic data used in the oil exploration activities. The bad seismic reflection may be attributed to many elements' such as the existence of volcanic rock within the sedimentary formations or due the occurrence of loose sand and lateritic soil on the surface of the basin. The objective of the present study is to investigate the causing factors of the bad seismic reflection through the integrated interpretation of remotely-sensed data and geophysical data including seismic and magnetic data. This study will rely on the utilization of remote sensing techniques such as standard colour compositing, PCA and band rationing techniques to delineate the surface features of the areas show poor seismic reflection phenomena. The outcome of the present study was evident that this area is dominated by iron deposits that lead to absorption of the seismic waves, where the bad reflection seismic data will be delineated. The results of these investigations will help in the planning of the future oil exploration works. Based on the study outcomes, the iron deposits dominated areas are note suitable for seismic shooting, unless the artificial parameters should be enhanced or digging below the iron band to avoid the energy loss.
موازنة المياه الجوفية لأعلي وأوسط حوض نهر القاش، شرق السودان
The study area lies in the Red Sea region of NE Sudan, which belongs to the Nubian Shield that or... more The study area lies in the Red Sea region of NE Sudan, which belongs to the Nubian Shield that originated during the Pan African Era. The Hamisana Shear Zone (HSZ) is a broad zone of cataclastic deformation in the Nubian Shield formed as prominent N-S trending major structure. The objective of this work is to recognize the structural manifestations through the remotely sensed data and field measurements for demarcation of the major structural styles and to study the structural evolution of the study area with respect to the tectonic events of the Nubian-Arabian Shield in NE Sudan. A set of four Landsat 7 ETM+ scenes (p172r45, p172r46, p173r45 and p173r46) has been mosaicked and subset to obtain a full coverage of the study area. Remote sensing data were supplemented by field observations and intense structural measurements. Ductile deformation has been obtained in macro-and meso-scales under different folding styles representing different deformation phases. In Landsat imagery, many...
The integration of remote sensing and satellite gravity data for regional geological mapping in poorly exposed geological terrains: cases from Sudan
Gravity data in Sudan are acquired in sedimentary basins that of great interest to the petroleum ... more Gravity data in Sudan are acquired in sedimentary basins that of great interest to the petroleum companies. The basement terrains do not attract the attention of the geophysicists. In this case, the satellite gravity qualifies itself as an alternative for studying the basement terrains from the stand point of lithologies and structures. Geological mapping represents the first step in deciphering the economic potentiality of an area and understanding its tectonic evolution. The traditional field-based mapping is not operational in terms of time, man power and costs. The utilization of remote sensing data in geological mapping have opened new horizon in mapping large areas in relatively short time frame, with little labors and low costs. However, remote sensing depends on the surface reflectance of the materials under investigation. Accordingly, areas characterized by poor rock exposures are hardly mapped via remote sensing means. The satellite gravity has the capability of revealing ...
Groundwater Resources Assessment for IDPs camps and Hosting Communities around Nyala Town, South Darfur State, Sudan
Over two million internally displaced persons (IDPs) are present in the three Darfur States. They... more Over two million internally displaced persons (IDPs) are present in the three Darfur States. They depend on groundwater from alluvial and fractured basement aquifers as the main source of water supply to secure their daily demands. The study is mainly oriented to investigate the groundwater resources in the IDPs camps and the hosting communities around Nyala Town, which represents one of the main IDPs settlements in Darfur region. The study is based primarily on 10 electronic logger's records in addition to the manual measurements and the analysis of the existed hydrogeological and hydrological data. The outcome of the present study indicates that only a little amount of the total precipitation replenishes the groundwater aquifers. The alluvial aquifers are vastly replenished through direct infiltration from precipitation and surface runoff. The fractured basement aquifers are characterized by less groundwater storage capacity compared with the alluvial aquifers; they show good ...
Journal of South American Earth Sciences
North Kordofan State represents the world’s main supplier of Gum Arabic in addition to considerab... more North Kordofan State represents the world’s main supplier of Gum Arabic in addition to considerable amount of livestock. Nevertheless, the area suffers from acute shortages of fresh water supply for both human and animal consumption. The overall objective of the present study is the investigation of groundwater occurrence through an integrated methodology incorporating remote sensing, lineament mapping, structural analysis and geophysical studies via electrical resistivity methods. The study area is located in semi-arid zone with annual average rainfalls range between 150 to 250 mm. Topographically, the area is flat with slight slopeto the northeast. Wadi Almilk and its tributaries represent the main source of groundwater recharge in addition to the direct precipitations. The alluvial, fractured and weathered basement are the main yielding groundwater source. The area is a part of a basement terrain, where the structural setting represents the main controlling factor of the aquifers...
Arbaat water balance published
The Khor Arbaat basin is the main source of potable water supply for the more than 750,000 inhabi... more The Khor Arbaat basin is the main source of potable water supply for the more than 750,000 inhabitants of Port Sudan, eastern Sudan. The variation in hydraulic conductivity and storage capacity is due to the heterogeneity of the sediments, which range from clay and silt to gravely sand and boulders. The water table rises during the summer and winter rainy seasons; it reaches its lowest level in the dry season. The storage capacity of the Khor Arbaat aquifer is estimated to be 21.75×10 6 m 3 . The annual recharge through the infiltra-tion of flood water is about 1.93×10 6 m 3 . The ground-water recharge, calculated as underground inflow at the 'upper gate', is 1.33×10 5 m 3 /year. The total annual groundwater recharge is 2.06 × 10 6 m 3 . The annual discharge through underground outflow at the 'lower gate' (through which groundwater flows onto the coastal plain) is 3.29×10 5 m 3 /year. Groundwater dis-charge due to pumping from Khor Arbaat basin is 4.38×10 6 m 3 /year...
Hydro-geophysical study in Al-Khogalab basement-sedimentary basin transition area using Vertical Electrical Sounding method, Khartoum State, Central Sudan
Open Transactions on Geosciences, 2014
ABSTRACT Groundwater represents the available source of fresh water in the northeastern part of K... more ABSTRACT Groundwater represents the available source of fresh water in the northeastern part of Khartoum State for drinking as well as for irrigation purposes. The objective of this study involves the assessment of the occurrence and potentiality of the groundwater in order to meet the increasing demand of water. The adopted methodology involves the digital processing of Landsat 8 OLI image and geophysical vertical electrical sounding (VES). VES data was processed and interpreted with the aid of IP2WIN computer Software. The outcome of the present study showed that the area is located in the transition zone between the basement and sedimentary terrains. The River Nile represents the main source of groundwater recharge from W and SW directions, with minor recharge source from the direct precipitations and seasonal valleys for the shallow groundwater aquifers. The depths to the basement vary from that basement exposed at the surface to more than 200m a.s.l. at the western part of the area. The very high resistivity values (>400 ohm/m) reflects the hard basement rocks, the high values (250-400 ohm/m) were interpreted as dry soils and gravels, while low resistivity values (<250 ohm/m) are related to sedimentary rocks. The conducted geo-electrical resistivity survey indicated that the basement exposed at the ground surface at the central part of the study area, while the considerable thickness of sedimentary rocks in the eastern and the western side of the area is preserved as a result of structural faulting. In term of sedimentary thickness and the recharge source, the western part of the area is considered the most potential zone for groundwater occurrence.
Groundwater balance in the Khor Arbaat basin, Red Sea State, eastern Sudan
Hydrogeology Journal, 2009
... The groundwater recharge in the Khor Arbaat basin occurs either when the area is flooded by s... more ... The groundwater recharge in the Khor Arbaat basin occurs either when the area is flooded by surface water, or when groundwater flows through the upper gate, or when rainfall infiltrates directly in the area between the upper and the lower gates. Sir Alexander Gibb and ...
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Conference Presentations by Abdalla El Sheikh
State -north east of Sudan, bounded by Lat 20° N to 21° N and Long 34° E to 35°
E, and covered over most part by geological formation that belong to the Arabian
Nubian Shield (ANS).
The area is very characteristic in lithological, structural and tectonic setting but it
lies in desert and accessibility is very difficult, so there are not enough detailed
geological studies. Using remote sensing, geographical information system (GIS),
structural analysis, geochemical evaluation and geological field observations the
present study has managed to shed light on geological characteristics of the area.
Color composite, band ratio, color transform and principle component analysis
(PCA) were applied in Landsat ETM+ image to increase the discrimination
between various lithological units, and augmented with GIS enabled the
protection of a detailed geological map.
The area is dominated by the highly sheared meta-volcanogenic group of low
grade which is intruded by Syn to late ‐ and post‐Orogenic igneous intrusions in
addition to mafic –ultramafic rocks.
The structural analyses show that the Hamisana Shear Zone (HSZ) is a broad
deformation at shearing trending N-S. From field check points a structural map is
constructed where five phases of deformations are recognizable: D1 is foliation,
D2 is upright tide folding, D3 is the NE-SW folding, D4 is the open refolding in E-
W and D5 is the reactivation of the N-S shearing, these phases including in three
episodes.
Many types of discrimination diagrams were used in geochemical analysis to
determine tectonic setting and geochemical environments from these diagrams.
The ultra-basic rocks from the mantle sequence are mainly metamorphic
peridotite and mafic and ultra-mafic cumulated which are harzburgite and
dunite. Pillow lavas and sheeted dykes are Tholeiitic within MORB and back arc
basin basalt. Chromite in the area is podiform chromite. Post and syn-orogenic
granite from trace element analyses are within plate granites (WPG).
Papers by Abdalla El Sheikh