كلية النفط والمعادن
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Item Resistivity and Self-Potential InvestigationsOfSubsurface Water Seepage PhenomenonAt Omdurman(ALNEELAIN UNIVERSITY, 2002-08) Mohsin Ali Elhag FahalABSTRACT The Omdurman subsurface water seepage problem constitutes a serious phenomenon at present because of the high- density population and lavish use of water. The Omdurman region is covered by rather flat Cretaceous Nubian sandstones with gentle centripetal dips that hinder the outflow of the groundwater into the River Nile. The sandstone bands are intercalated with mudstone layers or lenses, and injected by Tertiary basalts along the bedding planes. Both rock types are impervious and retard the inliltration of the surface water, hence over-flooding. Plastic clay soil (Banat east, Al- Abassia and AL-Ahlya square) when present may also hamper vertical water seepage, cause swelling potential and consequent damage. Geophysical investigations applying resistivity and selt potential (SP) methods are conducted to reveal the occurrence and distribution of the impervious layers underneath, and to detect the location and characteristic features of the subsurface streamlines. The results obtained indicate the presence of significant almost horizontal bands and lenticular bodies of mudstone intercalated with the sandstones of the Nubian formation. Some of these bands are situated close to the land surface e.g. at Bait- Almal, Al-Mulazmean, A1-Busta, Banat east and Al-Arda l districts. These layers have been successfully delineated by the electrical resistivity method. Geo-electrical sections and maps were constructed to show their locations, thicknesses, attitudes and inclinations. The mudstone layers being impervious prevent water infiltration from natural and artificial sources and can therefore, create temporary perched aquifers located at the interface between the superficial deposits and the top very layer or lens of the mudstones. From these aquifers water is expected to rise up and seep into the surface land and cause damage. Negative SP anomalies show the occurrence and variable intensities of the subsurface streamlines. The distribution of the SP contour lines indicate the haphazard orientation of water flow, hence, the phenomenon appears to be of local nature. 2Item ON the unification of physical fields(ALNEELAIN UNIVERSITY, 2008) ahmed hasan kathem meftahAbstract The most appropriate space for symmetry is the space of fiber bundle . The gauge group is symmetry group . The connection of fiber bundle represents the physical potential and the curvature manifests the field . It is for this reason that the theory of fiber bundles is extensively utilized in the study of gauge fields . In this research we consider the problem of unification of physical fields via the theory of fiber bundles . We treat gravitational field and the superimposed charges . We also treat the Euler — Lagrange equations in their global forms which are independent of coordinates . With the help of the bundle metric , the Euler — Lagrange equations of the unified field is obtained . Our main work and contribution concentrates on the interpretation of a charged particle as a geodesic in the fiber bundle where the projection is the usual path of the particle in Minkowski space . VItem Palynological and palaeoenvironmental interpretation of the Late Cretaceous to Tertiary strata of the Melut Basin (southeast Sudan)(ALNEELAIN UNIVERSITY, 2007) Ali Ahmed Mohamed Eisawim ABSTRACT A Late Cretaceous to Tertiary non-marine sequence of the Melut Rifi Basin in the southeastem Sudan was palynologically investigated. The recovered palynomorphs are overwhelmingly of terrestrial origin; few specimens of brackish water dinoflagellates and scolecodonts were encountered within the Lower Miocene and Oligocene/Miocene assemblages. The recovered palynomorphs are generally well preserved and fairly diversified. Based on the stratigraphic distribution of ninety-five selected spores and pollen species, compiled from three wells in the northem Melut Basin, eight palynozones covering the Campanian through the Neogene have been proposed. The identified zones are designated as Assemblage Zone I through VIII in stratigraphically ascending order as follows: Assemblage Zone I (Campanian), Assemblage Zone II (Campanian/Maastrichtian), Assemblage Zone III (Maastrichtian), Assemblage Zone IV (Mid-Late Paleocene), Assemblage Zone V (Early-Mid Eocene), Assemblage Zone VI (Oligocene/Miocene), Assemblage Zone VII (Early Miocene) and Assemblage Zone VIII (Late Miocene/ Pliocene). Out of more than 150 palynomorphs identified in the present investigation, only 25% of the species are Late Cretaceous elements, the remaining are Cenozoic material. In the Cenozoic assemblage, angiosperm pollen are most diverse, but pteridophytic spores and freshwater algae are most abundant. The angiosperm pollen are represented, among others, by Striatopollis, Bambacacidites, Retitricolpites, Retitrescolpites, Psilarriporites, Peregrinipollis, Pachydermites and Graminidires. The fem spores are represented by genera such as Deltoidospora, Cyathidires, Polypodiaceoisporites, Pteridacidiles, and Verrucatosporites, which represent the most abundant component of the Paleogene/Neogene palynomorph assemblages. Late Cretaceous angiosperm pollen are represented by Fuveotricolpites cf. giganleus, Cristaecolpites echinaceus, Monocolpopolleniles spheroidires, Auriculiidiles reticulatus, Syncolporites schrankii, as well as several pollen attributed to the Palmae and Proteaceae. Aquatic fern spores such as Gabonisporis vigourouxii and Ariadnaesporites spinosus and the hepatic spore Zlivisporis blanensis are present in the Campanian-Maastrichtian assemblages but disappear from the record in the Cenozoic assemblages.iv The coexistence of abundant structured organic palynodebris with the spores of aquatic ferns of the families Salviniaceae and Marsiliaceae observed within the Late Cretaceous sediments suggests swampy conditions within a predominantly fluvial setting. Frequent occurrence of pollen grains assigned to the Palmae group indicates the prevalence of warm, humid conditions during the Late Cretaceous, although seasonal aridity might be suggested due to the presence of Ephedripites spp. recorded from the Campanian and Campanian/Maastrichtian of well AY-3. Late Paleogene and Neogene assemblages are characterized by abundant amorphous organic matter, freshwater algae, appreciable amounts of fem spores and Gramineae pollen. Deposition in aquatic habitats such as fluvial plain and coastal swamps under warm-humid conditions is inferred. The occurrence of Gramineae pollen points towards the development of grassy areas under generally dry climate with marked rainy seasons. A presumably short marine invasion might have taken place during the Oligocene-Miocene, inferred from the rare occurrence of brackish water dinoflagellates and scolecodonts within the assemblage.Item HYDROCHEMISTRYOF GROUNDWATER IN KHARTOUM STATE CENTRAL SUDAN(ALNEELAIN UNIVERSITY, 2002-02) Hussien Salim AwadAbstract The groundwater chemistry of Khartoum State between longitudes 32° 00'-33° 0O’E and latitudes 15° O0’-16° 00'N was evaluated and assessed using different hydrogeological methods. Groxmdwater in the region occurs in two hydraulically interconnected aquifers. The siliciclastic sediments of the Cretaceous Omdurman Formation form the lower one, and the mostly unconsolidated sediments of the Cretaceous-Tertiary- Quaternary Umm Ruwaba Formation comprise the upper one. The evaluated hydrodynamic properties revealed unconfined conditions in most parts of the aquifers system and partial confinement in some parts, where clayey zones occur. The analysis of flow system indicated a regional flow direction towards the northwest, with a local flow regime towards the east. Preliminary assessment of grormdwater chemistry was investigated by using different statistical technique such as X-Y plots, correlation, cluster, principle components, and factor analyses. The results of analyzing data by these techniques showed negative correlation between the exchangeable ions, Na-Ca and Na-Mg, which means ion exchange process is active. The strong correlations among Na’ and Cl‘ ions, TDS and EC indicate that salinization is related to the increase of concentration of these ions. Dissolution process of evaporitic mineral is suggested by the strong positive correlations between Ca”, Mg” and SO42" Groundwaters were classified by -grouping them‘ into faeies~ For ~the—purpose of -classification, the pattern diagram of Lee, trilinear plots of Hill-Piper, Durov and by Chadha diagram. Three main types of hydrochemical facies were recognized, Ca-Mg-HCO,, Ca-SO,-HCO, and Na-Ca-S04-Cl. The spatial distribution of these facies and hydrochemical sections, indicate that the anionic facies changes in the flow direction from HCO,’ to SO42’ and finely to Cll. The cationic facies is mostly affected by ion-exchange process of calcium and magnesium by sodium. Mixing is an important and active process that has affected the water facies in the region. The saturation state of groundwater showed that, it is saturated with respect to carbonate minerals and undersaturated with respect to CO2 and sulphate. Assessment of groundwater quality at different locations indicated its suitability for all purposes except at few specified localities.Item Geophysical Exploration for Groundwater in Crystalline Rocks, El Obeid Area, North Kordofan, Sudan(Alneelain University, 2005-04) Abd El Rahman Ahmed AbbasharThe study area lies between latitudes 13° 22’ and 13° 05’ North and longitudes 30° 20’ and 30° 12’ East. The geology of the study area comprises the superficial deposits of Qoz sand, sands of different grain size, sandy clay, clay and silt overlie the Basement complex rocks. The Basement complex rocks consist of gneiss, quartzite, schist, granite and pegmatite. This type of geological formation is recognized as a poor aquifer for occurrence and accumulation of groundwater. Only in certain circumstances water may exist; that is in the presence of geological structures like fractures, joints, cracks faults.... Etc. The water quantity depends on resistivity of rainfall and infiltration in the study area. - In the current study geophysical techniques (electromagnetic and resistivity) were conducted to investigate the groundwater occurrence in the area. Ten electromagnetic profiles of total length 11.5 km, were conducted in the study area. The measurement reflects considerable fracturing, faults and cracks trending in North-South direction parallel to the streams or Wadis channel. ' Seven horizontal electrical resistivity profiles of total length 4.3 Km were carried out in the study area to locate anomaly sites and to verify the measurement done by electromagnetic profiles. These resistivity measurements insure the viability of locating sites by using the electromagnetic methods by giving better results in delineation of Basement rock structures. \ Finally fifteen vertical electrical soundings were applied in the study area in the center of the anomaly that shown by conduction of electromagnetic and electric resistivity profiles. These VES results confirm the result depicted by electromagnetic and electric resistivity profiles and, show depth to fresh Basement rock more than 54 meter in Kurbage locality, 77 — 135 m in El Sunut locality and 69 — 75 m in Jebel Kordofan locality which is a best locality compared to other two localities ( Kurbage and Elsunut ) in term of water quantity, quality and depth to water.Item Structural Control, Metamorphic Evolution and Genesis of the Gold Mineralization of Abu Khalag area, Central Bayuda Desert, River Nile State, Sudan.(Al-Neelain University, 2006-08) Mohammed Al NagashiThe study area constitutes part of east central Bayuda Desert; it lies about 400 Km North of Khartoum. It is composed of gneisses, schists, quartzites, calcsilicate rocks, marbles and amphibolites, which are metamorphosed under greenschist facies of regional metamorphism. These rocks were subjected to folding, shearing and fracturing accompanying metamorphism. The results of Abu Khalag rocks geochemical data show tholeiitic trends of high- grade amphibolites which indicate oceanic environment. The low-grade metavolcanosedimentary rocks show a calc-alkaline affinity, which suggests an island arc paleotectonic environment. The syn-tectonic intrusions have calc-alkaline affinity indicating a subduction related emplacement setting. The low-grade metasediments show a shelf environment of deposition. i Syn to late-granitoid intrusions were emplaced in weak planes of the above- mentioned units and have local thermal and metasomatic aureoles. Field observations have indicated that most of Au mineralized quartz veins in the study area are structurally and lithologically controlled. The auriferous quartz veins can be sub-divided into two phases, occupying fault planes, schistosity, bedding and traces of axial fold planes in permeable and reactive amphibolites and calcsilicate host rocks. The structural, mineralogical and geochemical characteristics together with the style of wall rock alteration of the investigated auriferous quartz veins suggest that they belong to the mesothermal type of gold mineralization. The study involves collecting samples of quartz veins and stream sediments. The background and threshold values are proposed for quartz veins as 0.2 ppm and 0.57 ppm respectively, and for stream sediments as 0.041 ppm, 0.3 ppm respectively. This study indicates that the trace elements Cu, Pb and Zn have greatest potential as indicator of gold mineralization and pathfinders.Item Hydro-geophysical Investigations of the . Upper Aquifer Abyei area, South Kordofan State, Sudan(Al Neelain University, 2008-03) Khalid Musa Mohamoud AliThe Geological and Geophysical Electrical method in combination with Hydrogeological methods were applied to study the availability and potentialities of the groundwater resources and quality in the upper part of Um Ruwaba Fonnation in Abyei Locality- South Western Sudan. The geological succession in the study area consists of Basement complex overlain by Nubian Cretaceous Sandstone Formation, Um Ruwaba Fonnation, and Superficial deposits. Baggara basin composed of Nubian sandstone formation overlain by Um Ruwaba series considered as main aquifers in the study area. Umm Ruwaba Series is composed of a variety of sediments, coarse and fne, well sorted and poorly sorted, penneable and impenneable. The depth to water table for upper aquifer varies from 09 m to 45 m. and from 36 m to 127m for the lower aquifer; the transmissivity generally varies between 6.42 X l0'3 m2/s and 3.39 X l0'3 ml/sj the average Hydraulic conductivity lies between 3.4 X l0'4 m/s and 9.61 X l0'4 m/s and the average porosity between 28% and 39%. ' The hydraulic gradient in this particular part is ranging from 0.002 to 0.003. The low hydraulic gradient indicates relative homogeneity and isotropy of good porosity and permeability of the aquifer. The close spacing of the groundwater flow contours in the northeast, west and east of the study area indicates relative anisotropic aquifer. The Wide spacing contours at the middle part of the northeast side are particularly due to the thick saturated sedimentary section and the high transmissivity of Um Ruwaba fonnation. The final directional component merge to the SW of the study area, the resultant flow moves out of the study area in the direction to the Bahr El Arab. The surface and near surface layer reflect wide range of resistivity values from 6 to 200 Qm. A few anomalous values are shown to fall between 540- 2240 Qm (VES 17, 18 &l9). The lower range generally describes clays & sandy clay sediments. This unit extends to an average depth of 40 m. The second unit in the column is indicated by a range of 18 — 280 Qm, high resistivity values observed on the top of the layer especially under VES (8), (9), (10) and (11) with the resistivity values 546, 688, 898 and 468 Qm respectively reflecting dry gravelly and/or coarse sandy formation. The lower resistivity values zones in the second unit is interpreted as Water bearing horizon as it lies generally below the static water level in the region. The aquifer also shows low resistivity values at the bottom of VES (5), which probably refer to sandy clay fonnation. The water bearing horizon shows depth of 30-140 m below ground surface. The third layer is characterized by consistent resistivity values ranging between 5- 20 Qm this unit is most probably clays, which dominates underneath. This unit is known here as the upper clays of the Baggara basin. The chemical composition of water indicates Na-Ca-Mg-HCO3 water type which is suitable for drinking, irrigation and industrial purposes.Item The Hydrogeology Of Jebl Mara Area With Special Emphasis On Water Quality,Western Sudan(Al Neelain University, 2004) Sami Hashim Mohamed MahmoudThe study area situated between longitude 24°.00'—25°.00' east and latitude l2°.30' and l4°.OO' north. The aim of the study is to cover the geology, hydrology with special emphasis on water quality (qualitative and quantitative). A field work was carried out several times to the study area as to collect water samples and field observations. Water samples from hand pumps, dug wells, wadis and hot springs were collected from the area in dry and wet season. Physical, chemical, and bacteriological analyses were done in different laboratories by applying standard methods given by A.P.H.A., and A.W.W.A., standard methods. Major cations, some, some trace elements and other water properties were examined for all samples in three recognized laboratories. Seasonal variation (dry & wet) of physico-chemical properties major cations, major anions, some trace elements shown by drawing seasonal variation graphs and aerial distribution maps of all elements. A comparison between water from wadis and hot springs was also done. The study revealed that samples from wells (hand & dug) consists of variable concentrations of ions all of them fall within the permissible limit given by Word Health Organization (W.H.O., 1984) except manganese, total iron zinc concentration were high and above the recommended values. Great deficiencies of iodine were detected throughout the study area (low or nil values) in all samples taken. About 95% of samples from wells (hand and dug) classified as Calcium-Sodium-Bicarbonate-Chloride type, and 5% as Calcium—Magnesium-Bicarbonate-Chloride type .Item GEOLOGY AND GEOCHEMISTRY OF EL TUWAL OPHIOLITIC COMPLEX AND ENVIRON S —_EAST CENTRAL SUDAN(Neelain University, 2008) Musab Awad Ahmed Hassan EljahABSTRACT Some 22400 sq. km have been regionally mapped around El Tuwal ophiolitic complex, east-central Sudanhtogether with a detailed geological map of the complex. The area is composed of gneisses, schists, quartzites and marbles, together with the ophiolitic rocks of E1 Tuwal complex, and basic metavolcanics of island-arc character. The layered sequences are intruded by syn-orogenic, I-type granitoids and unfoliated, “younger granite”, A-type complexes. The latter occur as hilly massifs rising above the subdued, flat clayey plains. Numerous dykes and quartz veins cut the older sequences among which is a prominent andesite dyke, some 20 km. long, cutting the syn-orogenic granites. .Late Cretaceous Nubian sediments overlie unconformably the basement sequences along the northeastem margin of the Butana area, and southeast of El Tuwal ophiolitic complex. Tertiary to Quaternary clayey cover usually obscures the subdued layered sequences. The ophiolitic rocks are clearly emplaced onto the other basement rocks by a SE-dipping thrust fault. They are composed of serpentinites and minor pyroxenites, which occupy the base of the complex, followed by gabbros and pillowed basic volcanics. Juxtaposed with structural contacts are the basic island-arc metavolcanics. The syn-orogenic granites cover a wide compositional spectrum exemplified by biotite and hornblende granites, granodiorites and tonalities to gabbros in decreasing abundance. The younger granite complexes are made up of granites, syenites, gabbros and volcanics in decreasing order of abundance. New geochemical data revealed that the ophiolitic rocks, associated arc metavolcanics and the syn-orogenic granitoids have geochemical signatures of subduction zone magmatism found in supra-subduction zone ophiolites and other arc rocks. The presence of podiform chromites in the studied serpentinites is considered to be typical of supra-subduction ophiolites with Cr# similar to those of subvolcanic ophiolites and boninite-derived chromites particularly those thought to be associated with fore-arc rifling. The “younger granite” complexes represent alkaline, within-plate continental igneous activity. The amphibolite facies gneisses, schists and marbles possibly represent earlier continental shelf sediments of the Saharan Metacraton. The ophiolitic rocks and the metavolcanics possibly represent ensimatic, thrusted material after the collision of the Nubian-Arabian Shield with the older sialic continental Saharan Metacraton during the late Proterozoic, Pan-African tectono-thermal event. The geological setting of the Butana area favours gold mineralization, and the granitoid rocks and the marbles can sustain successful building materials industry.Item GEOLOGY AND GEOCHEMISTRY OF EL TUWAL OPHIOLITIC COMPLEX AND ENVIRONS — EAST CENTRAL SUDAN(Al Neelain University, 2008) Musab Awad Ahmed Hassan EljahSome 22400 sq. km have been regionally mapped around El Tuwal ophiolitic complex, east-central Sudan, together with a detailed geological map of the complex. The area is composed of gneisses, schists, quartzites and marbles, together with the ophiolitic rocks of El Tuwal complex, and basic metavolcanics of island-arc character. The layered sequences are intruded by syn-orogenic, I-type granitoids and unfoliated, “younger granite”, A-type complexes. The latter occur as hilly massifs rising above the subdued, flat clayey plains. Numerous dykes and quartz veins cut the older sequences among which is a prominent andesite dyke, some 20 km. long, cutting the syn-orogenic granites. .Late Cretaceous Nubian sediments overlie unconformably the basement sequences along the northeastern margin of the Butana area, and southeast of El Tuwa] ophiolitic complex. Tertiary to Quaternary clayey cover usually obscures the subdued layered sequences. The ophiolitic rocks are clearly emplaced onto the other basement rocks by a SE-dipping thrust fault. They are composed of serpentinites and minor pyroxenites, which occupy the base of the complex, followed by gabbros and pillowed basic volcanics. Juxtaposed with structural contacts are the basic island-arc metavolcanics. The syn-orogenic granites cover a wide compositional spectrum exemplified by biotite and hornblende granites, granodiorites and tonalities to gabbros in decreasing abundance. The younger granite complexes are made up of granites, syenites, gabbros and volcanics in decreasing order of abundance. New geochemical data revealed that the ophiolitic rocks, associated arc metavolcanics and the syn-orogenic granitoids have geochemical signatures of subduction zone magmatism found in supra-subduction zone ophiolites and other are rocks. The presence of podiform chromites in the studied serpentinites is considered to be typical of supra-subduction ophiolites with Cr# similar to those of subvolcanic ophiolites and boninite-derived chromites particularly those thought to be associated with fore-are rifting. The “younger granite” complexes represent alkaline, within-plate continental igneous activity. The amphibolite facies gneisses, schists and marbles possibly represent earlier continental shelf sediments of the Saharan Metacraton. The ophiolitic rocks and the metavolcanics possibly represent ensimatie, thrusted material after the collision of the Nubian-Arabian Shield with the older sialic continental Saharan Metacraton during the late Proterozoic, Pan-African tectono-thermal event. The geological setting of the Butana area favours gold mineralization, and the granitoid rocks and the marbles can sustain successful building materials industry.