PHDtheses :Petroleum

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    The Hydrogeology Of Jebl Mara Area With Special Emphasis On Water Quality,Western Sudan
    (Al Neelain University, 2004) Sami Hashim Mohamed Mahmoud
    The 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 .
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    Gold Mineralization and Impacts of Its Mining on Environment
    (Neelain University, 2011) Karimeldin. Z. Al Samaui
    Abstract Mining makes a significant contribution to the national economy and local communities. This research briefly places the contribution of gold mining into the context of the wider economy and then focuses on the impact of its mining on the environment. Broadly, Sudan is endowed with multi-metal resources of which gold is the most economically attractive mineral. The gold mineralization is found, widespread in Sudan and confined primarily to the Archaean basement rocks and the Late-Proterozoic greenschist belts of the Arabia-Nubian shield. The recent studies of the Nubian-Arabian greenstone indicated that the Ariab metallogenic province is becoming one of the premier areas in the world for the development of poly-metallic base metal sulfide deposits, which contain substantial economic gold potential. Moreover, the secondary re-worked placer concentrates and detritus small nuggets of the pre-existing gold mineralization, attracted most of the present indigenous activities. The rapid expansion of formal and indigenous gold mining activities, particularly in the event of gold rushes after boom increase of gold prices, constituted one of the recent dominant challenges to economics, social developments and regional environmental impacts. Ariab open pit and Gebeit abandoned mines, which exhibited different gold extraction techniques of two genetically different ore formations, were taken as two study cases in this research. The study was based.on_the hypothesis that, mining .operations in the study areas have damaging impacts on the natural environment due to cumulative negative impacts generated from mine acidic water, leaching of heavy minerals from mine waste, relic tailings and the associated chemical effluents into the ecosystem. The results of the study have identified several features showing, positive and negative impacts, which are rather paradoxical in nature. From one side, the mining activities supported the increase of the national economy with appreciable sustainable social development as in Ariab disnict, but on the other side, undeniable negative effects at the mining sites have also accompanied these activities. Based on defined criteria, the impacts of mining and mineral processing operations were classified of low impacts at Ariab, and comparatively high at Gebeit with diiferent magnitudes on the ecosystem and communities. The chemical analysis and statistical correlations showed that, the mineral concentrations in mine waste and processed heaps, exhibit distinctive, elevated concentrations exceeding the local background and global limits by 46.1 and 99.2 times in arsenic, 4.6 and 8.4 in copper and 8.1 and 12.1 in lead respectively. The correlations between heavy minerals, Pb/Zn, Pb/Cd and As/Cd in the study area have shown also peculiar reaction behaviors due to cyanide influence and the pH level existing. Most of the heavy metals existed in the form of stable carbonate compounds of copper, lead, zinc, cadmium and as oxides of chromium, arsenic and antimony. However the drainage soil around Ariab gold mining sites has showed insignificant heavy metal pollution or acidification, derived fi'om the operation. That was, attributed to the advanced technology used and management control exerted during the mining operation. The qualitative and quantitative review of the heavy metals are presenting high elevated concentration values in the central zone where mining and processing were performed compared with the normal background (threshold) concentrations at up-stream zone. The down-stream zone concentration values were showing a close and analogous mineral distribution to the local backgroimd (threshold) and global concentration limits. This phenomenon has concluded with facts that the influence and the effects of heavy metals generated from mine waste, heap-leached tailings and mine acid water on the ecosystem is negligible. In contrast, abandoned mines tend to have far more extensive and accumulated impacts to the environment context. The dust emission has been, significantly reduced by the new installation of dust suckers and the surveillance results of dust threats on resident’s health is insignificant. Although indigenous mining has positive socio-economic contributions, but it also contributes to land degradation, loss of biodiversity, destruction of natural resources, deforestation , water and soil mercury pollution . The study showed that it is difficult to prevent pollution altogether during mining, but it is advisable to determine the optimal level of pollution or pollution connol by balancing the cost and threats of polluting activities against the improvement of the national economy and social development as strategy.
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    GEOTECHNICAL PROPERTIES OF SUB-SOIL AND GEOTECHNICAL MAPPING OF AL-KHOBAR- DHAHRAN-DAIVHVIAM AREA, KSA
    (Neelain University, 2015) KAMAL MOHAMMAD ALIFADLALLAH
    ABSTRACT The geotechnical properties of subsurface soil and rock formations of Khobar - Dhahran and parts of Dammam city , covering an area of about 675 sq.km were investigated during this study. ~ The geotechnical properties were determined through field and laboratory tests. Field testing was conducted by SPT; standard penetration tests, CPT, cone penetration test and PMT, pressuremeter tests. The- index properties as grain’ size analysis , moisture content and plasticity limits were determined in the laboratory . Strength tests as unconfined compressive strength , undrained shear strength as well as one dimensional consolidation properties were also determined . The chemical properties of soil and water samples were also analyzed . Soil types encountered within the study area were determined depending on their geotechnical properties. The study area is divided into four zones of similar properties . ' I Zone I , is a very loose to loose, saturated, sabkha soil, that consist mainly of poorly graded sand, silty sand, sandy silt and sandy clay. Vertical and horizontal extent of this material indicated that soils within zone I are mainly characterized by low bearing capacity and higher settlement. These loose bearing strata , needs to be improved before constructing even light structures as one to two storied villas , on them. Soil improvement within zone I can be done by preloading, dynamic compaction or use of stone columns. The method of soil improvement should be selected based on soil type and thickness , type of structure and loads as well as economy . Zone II , covers the coastal plain of AL-Khobar city and parts of Dammam city. Soils encountered in this stripvare, backfill and reclaimed soil ‘in the upper 2m, followed by loose sand till a depth of about 7m and dense sand till a depth of 15m to 18m. Stifl' to hard clay layers were encountered below dense sand till a depth of about 50m below existing ground surface. Zone HI covers an area of about 300sq.krn. Two major soil types were encountered in this area, the residual calcareous soils and the sand deposits. Residual calcareous soils are the product of weathering of parent calcareous rocks in the area. Sand deposits are mainly wind-blown sand that deposited on outcropping rocks, wadis or covering residual soils. Both residual soil and sa.nd deposits are dense/hard and rarely loose or sofi. Zone IV, is mainly covered by outcropping calcareous rocks of the central part of Dammam Dome. Most of these rocks belong to Rus and Dammam formation. The major rock types encountered in Zone IV are limestone , marlstone and shale. Limestone i_s generally light cream, moderately weathered, fractured, voided, partly cavemous and moderately weak to strong. Marlstone is highly to moderately weathered, fractured and voided rock with very poor to poor RQD and moderately weak to moderately strong . Shale is mostly belonging to Salia and Medra members of Dammam formation. It is highly weathered, fractured, less voided with very poor to poor RQD and weak to moderately weak strength. Groundwater was encountered at an average depth of 1.0m within sabkha flat , at a depth of 1.74m in Zone II and a depth of 3.15m in Zone III . Groundwater is generally below 10m in Zone IV . The chemical analysis of both soil and water fiom different zones , show a high to very high concentration of salts ( TDS , chloride and sulphates). These high concentrations of salts, give rise to a very aggressive and corrosive ‘environment whereby good quality concrete using sulphate resisting cement, pozzolanic materials , corrosion inhibitors and suitable water proofing membranes and sutable concrete covers are required. A multipurpose, comprehensive, medium scale geotechnicall engineering geological map is prepared. This map is considered useful, valuable and l'16lpfi1lfO1' planners, developers, designers as well as researchers interested in the area. " It is highly recommended to extent this work to cover other parts of Dammam city and its tenitories as Sihat , Qatif and Ras Tanura . A hazardous map showing locations of cavernous rocks , uncontrolled fills and liquefiable soil is also prepared . Since settlement is the controlling design criteria for cohesionless soils, other than bearing capacity , it is estimated following Burland & Burbridge (1985) , semi-empirical procedure which gives reliable values for design of shallow foundations in most areas . Standard penetration test results obtained from some -‘sites , were correlated with modulus of elasticity from pressuremeter tests conducted on the same sites . The correlated values were used in estimation of settlement and values obtained are very close to those of Burland & Burbridge method .
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    Assessement of Integrated Geophysical Groundwater Prospecting Methods ON Basement Comiplex Aqutfersin NE Nuba Mountains - Sudan
    (جامعة النيلين, 2007) NUHA ELZEIN MOHAMED
    .r.;- I r .e | ~ Abstract A _,.~~ Integrated geophysical methods were applied to map the groundwater aquifers on complex geological settings, in the crystalline basement terrain in northeast Nuba Mountains, which are structurally controlled. The water flow is controlled by the northwest-southeast extensional faults as one of several in-situ deformational patterns that are attributed to the collisioniof the Pan-African oceanic assemblage dfthe Nubian shield against the pre-Pan African continental crust to the west. The used assessments are the electrical resistivity tomography (ERT), very low frequency-resistivity (VLF-R), and the audio magneto telluric (AMT) soundings, vertical electrical soundings (VES) in addition to water quality analysis and petrophysical measurements. These measurements were designed to be overlapped in order to prove the reproducibility of the geophysical data and to provide better interpretation of the hydrogeological setting in the aquifer complex structure. Different inversion schemes, accomplished by means of a cluster analysis, were attempted for the synthetic and observed ERT data to study their reliability to map the different geometries in the complex subsurface such as fault and graben structures. The sedimentary sequence is not symmetrical due the seasonal variations of the flow direction. Variations of the basement types were also recorded by their resistivity values and consequently their weathered products influence the water quality. The VLF-R data with Transverse Electric (TE) mode has been collected using the transmission stations GBR, GBZ and RHA of frequencies 16.0, l9.6 and 23.4 kHz respectively and it was two dimension (ZD) laterally-constrained inverted in a smoothly 2D resistivity distribution model after manual incorporation of a priori data . The inverted ERT and VLF-R lines confirmed the fracture zones and the deeper basins. Eight AMT soundings were acquired. True resistivity values and their relevant thickness were calculated and viewed as three dimension (3D) surface images. The VES data was conducted, where ERT survey was not accessible, and inverted smoothly and merged with the ERT in the 3D resistivity grid. Synthetic magnetotellurics MT data enabled us to test the inconsistencies between die interpreted geophysical results and the geologic expectations across AlBetira fold. Hydrochemical analysis (analyses) was applied to 42 water samples collected from the (hand) dug wells in the study area. Extremely high saline zones due to different reasons were recorded. Petrophysical measurements of an artificial saturated aquifer, using different soil types and various water salinities, provided a range for the porosity, formation factor and resistivity of the bulk formation and the later can be represented in terms of grain size distribution. A combination between the electric conductivity (EC) data and iso-resistivity horizons provides a better resolution of the target aquifer location, type and grain size distribution. The formation factor I was estimated from the EC map and the corresponded bulk resistivity from the depth slices (W) and it varies from 1 to 6.7, except of Abu Gebiha which reaches 18. This result is confirmed by the previous petrophysical measurements and in addition to the water quality analysis, drainage pattems, and faults locations derived from VLF-R and ERT data. New target aquifers were suggested in the north eastem part of Al Terter area and along both Khor Baggara and Khor BanGadid in Al Betira area with respect to the water quality in both localities, and the southem pans of AbuGebiha town is considered as reasonable targets for groundwater supply. ii
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    GEOTECHNICAL INVESTIGATION AND FOUNDATION RECOMMENDATIONS FOR JEDDAH CITY THE KINGDOM OF SAUDI ARABIA
    (Neelain University, 2008) SOLEIMAN HASSAN KODEIH
    This thesis presents the findings of the geotechnical investigation of the subsurface conditions that have been conducted for the Jeddah City that located at the central western sector of The Kingdom of Saudi Arabia. The work was carried out to fulfill the requirements ofdoctorate degree in Engineering Geology for Jeddah area in Saudi Arabia by Al Neelain University — Graduate College -, Sudan. The field investigation was performed from October 05, 2005 through March 14, 2007. The field investigation work was carried out by mainly drilling fifty one (51) boreholes distributed at six (6) zones depending on the type of subsurface formations encountered. The zones locations are as follow: 0 Zone l: north west of Jeddah 0 Zone 2: central north east of Jeddah 0 Zone 3: south west of Jeddah Q Zone 4: central south of J eddah v Zone 5: east of Jeddah I Zone 6: central north of Jeddah Generally, Residual soil was encountered at the area of zone two and zone four and coralline formations was found at the location of zone one, three and six. Rocky formation was encountered at the area of zone five at the eastern sector of Jeddah area. The residual soils are composed of brown to light brown, medium dense to very dense, silty or clayey sand with gravel and/or some cobbles and located at the eastern sector before the mountain area (zone 5)
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    The impact of water pollution on White Nile Water quality and fisheries at Khartoum state
    (Neelain University, 2011) ABD ELGADIR MOHAMED AHMED MAN OFAL
    Abstract , A ' This study was carried out during February 2009-August 2010 to investigate the impacts of sewage and industrial disposal from Elauzozab musruf into the White Nile around Khartoum on water quality, planktonic community and accumulationvlevels of Cd and Pb in fish (Orechromis niloticus). ' ' Samples-of water and plankton were taken monthly from four sites: J ebel Aulia (upstream),Al musraf, Elauzozab (disposal site), Almogran (downstream). _ Samples of water -for'physical and chemical analysis, Gills of fish (Orechromis nil0ticus)_~were examined for accumulation level of Cd and Pb as biological indicators of water pollution. The result revealed: ‘. . ' i At the disposal site and downstream sewage effluent increased conductivity (sss umho), TDS (492 mg/L), TSS (137 mg/L), BOD (30 mg/L), COD (56 mg/L), P04-P (0.46mg/L), NO;-N (l2mg/L), Cf! (0.54mg/L), Cd= (o.s6 mg/L), Pb = (0.45 mg/L) and depleted dissolved oxygen (4_mg/L). The maximum planktonic growth occurred in winter 2010 whereas the minimum growth rates recorded in summer and July 2010 and almost disappeared in autumn 2009(August to October). The pattern of abundance in phytoplankton was almost reversed, due of many diatoms replaced by blue green algae and the appearance of Euglenophyceae. In Zooplankton copepods dominated over cladocerans and Rotifers which were of less abundance . The accumulation levels of Cd and Pb in Orechromis niloticus gills confirm the presence of high significant levels of Cd (1.518 ug\g) and Pb (2.l65ug\g) lthle concentration of Cd and Pb in water and fish gills exceeds the permitted limits by WHO and Sudanese standard for drinking water guideline.(Cr,0.005mg/1, Cd=0.005mg/1, Pb=0.05mg/l) . _ The finding contributes to understanding of distribution and dynamics‘ of pollutants in the White Nile ecosystems
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    Evaluation of the Coastal Plain Aquifer Physical Parameters in Gaza Strip
    (Al Neelain University, 2005) Samir Khalil Shaath
    Gaza Strip like some other parts of the Middle East countries has distinct and serious deficit in water. Currently, there is a water sholftag problem for most of the Gaza Strip’s residents. The quality of consulmfed water has very grave problems, as some bacteriological contamination, lasl well as increase in nitrates and chlorides to levels which already have been above the safety limit. Further more it is forecasted that the quantity of available water, which is already scarce, may drop to incompatible levelsl with an acceptable standard of living, public health, social and economid development in the region. To solve the quantity shortage problem in Gaza Strip, correct data about the physical aquifer parameters should be available. Si-ace; hydrogeological studies about Gaza Strip aquifer are not available; an' accurate scientific research will present the basis of figuring the aquifer parameters, which may help in calculating the amount of stored water in the aquifer and can be performed in the lield by either direct method, or by indirect method. Every aquifer has its own physical parameters (Characteristics), as Porosity (E), Transmissivity (T), and Storage Coefficient (S), these physical parameters control the fluids passage through the aquifer. To study any aquifer, we must calculate the aquifer phvsical parameters by executing some tests and analyze their results, from these tests the. pumping test can be used. The aim of this research is to find some physical characteristics for; the Coastal Plain Aquifer in Gaza Strip. as values for Transmissivity (T) and Storage Coefficient (S). l I This study showed that, the water quantity is decreasing year after year, and the quality of water is in continuous deteriorating. There are some suggestions to increase the water quantity in the reservoir, and it is recommended to decrease the usage of \vater and use the water wisely.
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    REMOTE SENSING AND GIS APPLICATIONS IN GEOLOGICAL MAPPING, PROSPECTING FOR MINERAL DEPOSITS AND GROUNDWATER-BERBER SHEET AREA, NORTHERN SUDAN
    (Al Neelain University, 2006-09) SAMI OMER HAG EL KHIDIR
    The geology of the East Bayuda Desert —Abiydia (Berber Sheet, NE-36-G) area in the north Sudan, has been investigated by means of remote sensing and Geo-Information System (GIS) techniques and limited geotraverses. Digital image processing of Landsat ETM+7 data and geo-spatial analysis were conducted to evaluate the use of remotely sensed data in geological mapping, mineral prospecting and hydrogeological investigation in such arid terranes. The study area represents a part of Bayuda terrane, and comprises Basement Complex rocks of Neoproterozoic age. The lithologies include the high-grade gneisses and migmatites, dismembered ophiolitic basic-ultrabasic rocks, metavolcanosedimentary sequence and supracrustal metasediments. These units have been intruded by syn- to late- and post-orogenic intrusions during and afler the Pan-African orogeny. Phanerozoic sedimentary Formations cover the Basement Complex rocks, which in turn have been covered by Cainozoic basaltic volcanics. Most of these units have been covered in parts by Quatemary Nile silts, alluvial deposits and / or aeolian sand sheets. The East African Orogen has been manifested in the study area. The collision between the west and east Gondwanaland continents resulted in at least five deformational phases, which can be traced in Satellite image. The three ductile and two brittle deformational phases result from the collision of the Bayuda terrane with Halfa and Gabgaba terranes. The first discemible deformational phase displayed by the isoclinal folds with E-W fold axis. These folds were refolded by close folds in NE-SW fold-axis fold. A third phase of open folds refolded the earlier fold with E-W fold axis. The ductile deformation has been followed by brittle deformational phase. The NE-SW trend Nakasib shear affected earlier structures, which in tum has been superimposed by N-S trend Keraf shear zone. Digital image processing was conducted to enhance the visual interpretation of the Landsat ETM+7 data. The IHS (Intensity-Hue —Saturation) transformation of the decorrelated stretched bands yielded an overall good lithologic discrimination. The two colour composite images 7, 4, l and 7, 5, 4 have been decorrelated stretched and then IHS transformed with the panchromatic band. The two colour composite images display well saturated hues and morphological signatures, which make them the best in discriminating various lithological units. The Principal Component transformations yield saturated images and resulted in a higher signal-to — noise ratio when standardized coefficients were used instead of the covariance matrices. Band ratioing images yielded geologically informative images, where both spectral and morphological information are preserved. Selective merged images were used by combined in the red-green-blue colour gun different and theless correlated images from various techniques. Colour composite images Litho-l, Litho-2 and drainage-image have been built. The Litho-1 colour composite image utilizes the PC2 (of the six bands) in red, band ratio 5/7 in green and DC2 (of bands 5, 4 & 3) in blue. The Litho-2 colour composite image utilizes PC2 (of the six bands) in red, DC2 (of bands 5, 4 & 3) in green and band ratio 3/1 *5/7 in blue. The drainage colour composite image utilizes band ratio 5/7, DC2 (of bands 5, 4 & 3), PC5 (of the six bands) in red, green and blue, respectively. These saturated and morphological expressed images display well discrimination ability of diverse lithological unit and structural elements. On the hand the drainage image created by selecting the band ratio 5/7, DC2 (of bands 5, 4 & 3) and PC5 (of the six bands) in the R, G and B, respectively. It was found that this image is superior in delineation the alluvial in the wadies, thus it was used mainly in mapping them. Geological map of Berber Sheet (scale of l:250000) has been produced utilizing the Geo- Berber database. The Geo-Berber includes the digitally processed remotely sensed data, field work and structural and petrographical data. These data combined with demographic data. The SRTM data provide the base for the elevation data in the geo-database. The extracted DEM render the 3D terrane visual image that assists the lithological discrimination by its morphological expression. The geo-spatially analysed lineaments data used in the Geo-Berber database have been produced by the spatial and structural analyses of the edge enha.nced- filtered Landsat images. Prospecting for mineral deposits has been exploited using the spectral criteria of the gossans and rock alteration associated with mineralization. The geo-spatially analysed- supervised classified colour composite images of Crosta (Feature Oriented Principal Components image) and Sabin’s ratio image proved to support the demarcation of the mineralization. The results are found to be controlled with the level of erosion as witnessed in the deeply eroded terranes as in the East Bayuda Desert and Abidiya areas. In the mineralized Ariab-NW Nakasib area that is characterized by low-level of erosion, the technique revealed optimum results in depicting the gossans. This malfunction in the remote sensing-GIS mineral prospecting model can be overcome by combining other geological and structural information in the geo-spatial analysis. A remote sensing-GIS model for depicting fractures and structurally-controlled aquifers in crystalline rocks prove to guide the prospecting of groundwater in Basement Complex terrane of the East Bayuda Desert. Digital image processing, lineament analysis and geo- spatial analysis combined with ground geophysical investigation gave best possible results as documented by the drilling activities.
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    Digital Image Processing of Landsat7 data and GIS Application for Geological Investigation in Jebel Erba Area, _ Red Sea Hills, NE Sudan _
    (Al Neelain University, 2006-09) Ibrahim Ahmed Ali Babikir
    Digital image ‘processing and Geographic Information System techniques, together with a limited reconnaissance ground truthing, have been used to investigate the geology of the area around J. Erba and J. Oda of the Sudanese‘ Red Sea Hills (RSH). The methodology fulfilled and the procedures followed during this study enabled the establishment of geodatabase named GeoRSl-I and the production of two geological maps of scale l:250,000. The area of study occupies the central part of RSH of Sudan that belongs to the Nubian Sector of the Arabian-Nubian Shield (ANS). It forms part of the Gebeit terrain that is known to be created among the other four terrains of NE Sudan (Tokar, Heya, Gabgaba and Geri) during the Pan-African event (950-50OMa) due to subduction-related processes and collisional tectonics and sutured together byidismembered-ophiolite belts and major shear zones. The geology of the area comprises high-grade gneisses, volcanosedimentary sequences metamorphosed in the greenschist facies, all intruded by syn and syn-to-late orogenic calc-alkaline intrusives and post-orogenic alkaline bimodal gabbro-granite complexes. The coastal plain is geologically characterized by Cenozoic siliciclastic and shallow marine rift- related sedimentary sequences. Pliocene-Pleistocene is represented by the thick older gravel unit and the emergent linear reef terraces. I - - i Several digital image processing techniques have been implemented to enhance the Landsat7 ETM+ digital satellite data. A Digital mosaic that covers almost all the Sudanese Red Sea Hills has been created using nine Landsat7 scenes. A 3x3 high-pass filtered color composite image with a central coefficient of 16 proves to create the most optimized images that appear relatively brighter and more saturated. Four color composite triplets of band ratio images; B3/B5, B3/B1, B5/B7; B5/B7, B5/B4, B3/Bl; B5/B7, B5/B1, (B3/B4)(B5/B4) and B5/B7, B3/Bl, B4/B3, have been composed to assist geological mapping. Directed band ratioing of the ratio color composite (B5/B7, B5/B4, B3/Bl) resulted in a well enhanced image that is characterized by satisfying saturated colors,‘ strong retention of ‘topographic expression and well pronounced lithological discrimination. Unstandardized and standardized principal component analyses have been done using the six reflected bands as well as a four selected bands. Some of their resulted images show relatively clear Landcover differentiation. Detailed lineaments investigation has been done using high-pass filtered, directional-filtered images as well aslthne DEM. The lineaments ofithe study area show a clear bimodal pattern where a dominant N-S (360° i 10°) and subdominant E-W (90° i 10°) trend. The N-S lineaments are attributed to the shear fracture system that resulted from Heya-Gebeit terrain collisional episode and the NW-SE compressional forces that prevailed during the Neoproterozoic time. The E-W trending lineaments have been interpreted to result from the locally deflected, landward extension and propagation of the Red Sea rift-related transform faults. Dykes and dyke swarms present in the study area display a prominent unimodalpattern with a prominent E-W direction. These dykes were probably emplaced during a compressive condition with a minimum principal compressive stress that trends 350°-360°. This direction corresponds to the main direction of the N-S trending Pan‘-African sinistral master faults related to Onib-Sol Hamid and Baraka major shear zones. Shuttle Radar Topography Mission (SRTM) data of 90m resolution that covers the study area have been Well utilized. Contour maps, shaded relief images as well as 3D scenes have been deduced from the SRTM data. The 3D scenes enhanced the visualization of the different geospatial data stored in the constructed geodatabase. A GIS-based geodatabase (GeoRSH) has been designed for the study area. It is structured to include all the available spatial data that have been stored in four group layers namely; the Infrastructure, Topography, Geology and Processed Satellite data group layers. GIS cartography has been implemented" to assist the final design of the two geological maps of scale l:250,000. The final layout of the two maps has been prepared in a GIS framework.
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    Integration of Geophysical Techniques for Archaeological Prospection in Sudan.
    (Al Neelain University, 2007-05) Mohamed Abdelwahab Mohamed Ali
    The geophysical data in the current study have been measured in four archaeological sites in Sudan. The studied sites include Meroe city, Domat Al-Hamadab, Musawwarat es Sufra and Jebel Barkal. The geophysical methods, which are suitable for each site, were selected on base of the physical contrast of the specific parameter of each method. This parameter represents magnetic susceptibility in magnetic method, electrical resistivity in resistivity method and dielectric permittivity in ground penetrating radar. The magnetic data in the studied archaeological sites in Sudan have been measured using three different magnetometers. The first one (caesium magnetometer with accuracy 1 0.01 nT) measures the total magnetic fields. The second one (Overhauser magnetometer :t: 0.1 nT) measures the vertical gradient of the total magnetic field and the third one (Fluxgate gradiometer :\: 0.1 nT) measures the vertical gradient of vertical component of the magnetic field using portable magnetometer/gradiometer. The magnetic surveys were complemented by resistivity mapping to investigate the archaeological features horizontally when these features have contrast in_ the magnetic susceptibility and resistivity to their surroundings. The complementary magnetic and resistivity mapping surveys have been integrated with electrical resistivity imaging (ERI) and ground penetrating radar (GPR) data, in profiles with locations selected on base of the magnetic and resistivity results. The ERI and GPR profiles provided complementary information about the variation of the anomalies related to the archaeological features with depth. The integrated interpretation of these methods leads to better understand the target features and accordingly helps the archaeologists witl1 some hints for correct conclusions. The integrated prospection results (chapter 5) convinced the archaeologist to replace some of the archaeological excavation by geophysical surveys to complete the missing parts of the site maps. Test excavations have been carried out for field check of the geophysical interpretation. This study shows how it is successful using geophysical processing techniques to improve signals of the geophysical data from archaeological sites so as to extract the maximum information from these data, and then gives better chances for successful interpretations. Basic theory and algorithms of the geophysical methods and processing techniques are used not only for explaining the successful techniques, but also for defining the problematic ones and introducing and recommending methods to overcome the encountered problems. It is demonstrated that geochemical analysis and magnetic susceptibility measurements can give some indications for explaining the success and failure of archaeological prospection using magnetic surveys. The magnetic gradient revealed the presence of some fairly clear archaeological building structures in the different studied sites. It is shown that such measurements are more effective to detect the shallow archaeological features than the total magnetic field measurements, which enhance the anomalies'of deeper sources. The geochemical analysis and magnetic susceptibility results of the collected samples, which represent the construction and the surrounding materials in the studied sites, indicate that sandstone as non-magnetic material can be detected successfully, when it is embedded in magnetic background. The fired-bricks may have higher magnetic susceptibilities. Therefore, they are shown in the magnetic images very clearly. Depending on the scale of the prospected features, comparison between coarse sampling pattern (e.g. 0.5 m) and fine sampling pattern (0.25 m) has been done. The first one was used in the reconnaissance‘ survey, but small-scale sampling pattern was required to resolve the small-scale anomalies more clearly. 3D modeling and inversion of the magnetic data of the studied area have been done using a priori infonnation, which were of great help to select a good starting model for the inversion process and then ending in a plausible model for the modeled anomalies with low rms error. ' 1D vertical electrical sounding (ID-VES) measurements have been used to give general estimation of the vertical extension of the prospected features. Furthermore, it helps to describe geological conditions of the archaeological features and their surroundings. 2D resistivity imaging profiles with small electrode- spacing (0.25 m, 0.5 or l m -depending on the scale of target anomalies) have been carried out along locations selected on base of magnetic, 1D-VES and resistivity mapping results. The resistivity inversion results of these profiles helped to estimate the vertical extensions of the archaeological targets more precisely. The applicability of combining 2-D electrical resistivity imaging (2D-ERI) profiles in 3-D data set for inversion using a 3-D resistivity inversion code is also demonstrated. High frequency (500 MHZ) ground penetrating radar (GPR) replaced 2D-ERI in arid and semi-arid area, where conditions favor the use GPR. The integrated interpretation of these methods leads to better understand the target features and accordingly helps the archaeologists with some hint for correct conclusions. This study can be used to pave the way for an increased use of geophysical techniques in the cultural heritage management of archaeological sites in Sudan.