Department of Geology
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ItemKnockdown Insecticide Resistance (KDR) Mutation in Two Populations of Aedes aegypti from Sudan( 2021)Abstract In this study Aedes aegypti was collected from two cities in eastern Sudan. The main objectives of this study were: to provide baseline data on insecticide susceptibility status of natural populations of Aedes aegypti in two cities in eastern Sudan and to detect the knockdown insecticide resistance mutation (kdr) and determine its allele frequencies. Entomological cross-sectional surveys were carried out in Port Sudan and Kassala. Insecticides bioassays were conducted using the World Health Organization (WHO) standard kits for Permethrin (0.75%), Bendiocarb (0.1%), Malathion (5%) and DDT (4%). A diagnostic two allele-specific PCR assays were used to detect mutations in the voltage-sensitive sodium channel (vgsc) gene. In both cities, the mortality rate was 100% for both Bendiocarb and Permethrin insecticides. In Port Sudan, the mortality rate for Malathion was 98% whereas in Kassala it was 99%. In both cities, mosquitoes were highly resistant to DDT with mortality rate of 5% in Port Sudan and 38% in Kassala. The kdr allele frequencies varied greatly for DDT. The kdr susceptible allele frequency was 0.25 in Port Sudan and 0.60 in Kassala. The kdr mutation F1534 was absent in all mosquitoes exposed to Permethrin in both cities. Mosquitoes collected from Port Sudan and treated with DDT were found departed from Hardy-Weinberg Equilibrium (HWE) (P=0.038). In contrast to this, mosquitoes collected from Kassala were in HWE. The F1534C kdr mutation detected in both cities in mosquitoes exposed to DDT. This is the first record of this mutation in Sudan. A weak association between survivorship and F1534 kdr mutation was detected in Port Sudan (Odd ratio (OR) = 0.104; P = 00.049) and a strong association was detected in Kassala (OR= 9.2; P = 0.003). Conclusion: the present study findings provide baseline data for the insecticide status to use for Aedes aegypti control in each city in addition to providing baseline data regarding kdr mutation and frequency. iv المستخلص كانت األهداف الرئيسية لهذه الدراسة هي توفير بيانات أساسية عن حالة التاثر بالمبيدات الحشرية للمجموعات الطبيعية من الزاعجة المصرية والكشف عن طفرة مقاومة المبيدات الحشرية )كى. دى .ار( وتحديد ترددات اليلها. تم إجراء المسوحات المقطعية للحشرات في مدينتي بورتسودان وكسال . تم إجراءاختبارات الحساسية للمبيدات الحشرية باستخدام مجموعات منظمة الصحة العالمية المعيارية للبيرميثرين )0..5 ، )٪بنديوكارب )0.5 ، )٪ المالثيون )0 )٪والدي دي تي )4 . )٪تم استخدام اختبار تفاعل البلمره المتسلسل التشخيصي الكتشاف الطفرات في مورث قناة الصوديوم الحساسة للجهد باستخدام اختبارين من تفاعل البلمره التسلسلى الخاصين باالليل. فى كلتا المدينتين كان معدل الوفيات 055 %لكل من مبيدات البينديوكارب والبيرمثرين . بلغ معدل الوفيات للمالثيون 99 % فى كسال ،بينما فى بورتسودان كان 99 .%فى كلتا المديتين كان البعوض شديد المقاومة لمبيد ال دي.دي.تي بمعدل وفيات 0 %فى بورتسودان و38 %فى كسال. تباينت ترددات االليل بشكل كبير لل دى دى تى . بلغ تردد اليل الحساسية 0..5 فى بورتسودان و5..5 فى كسال .كانت طفرة كى دى ار اف 0054 غائبة فى جميع البعوض المعرض للبيرمثرين فى كلتا المدينتين .. وجد ان البعوض الذي تم جمعه من بورتسودان و الذي تمت معالجته بالـ مبتعدا x ً (دي.دي.تي عن هارى واينبرغ 2 (038.0 = P, test -مما يشير الى قوة تطورية فى العمل وعلى النقيض من ذلك كان البعوض الذي تم جمعه من كسال يتطابق مع حالة اتزان هاردى واينبرغ. تم اكتشاف طفرة ال كى دى ار فى كلتا المدينتين فى البعوض المعرض لل دى دى تى . تم اكتشاف ارتباط قوى بين البقاء على قيد الحياة وطفرة كى دى ار اف 0054 فى كسال )نسبة اإلحتمال ..9 , 003.0 = P ) وتم اكتشاف ارتباط ضعيف فى بورتسودان . ) P = 00.049, 5.054 اإلحتمال نسبة) الخالصة: تقدم هذه الدراسة اإلكتشاف االول لطفرة كى دى ار اف 0054فى السودان كما توفر نتائج الدراسة الحالية بيانات اساسية عن حالة المبيدات الحشرية لتوجيه خطط امكافحة ناقالت االمراض من الزاعجة المصرية فى مدينتى كسال وبورتسودان.
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ItemGeochemical Evaluation of Rare metals (Nb, Ta, Sn and W) Mineralization of Selected Younger Granites and Pegmatites in the Bayuda Desert- Sudan(University of Khartoum, 2021-01)Abstract The study area is located in central Bayuda Desert, northern Sudan. It’s bounded by Latitudes 170 52’’ 18.2’ N and 180 16’’ 09.9’ N; and longitudes 330 00’’ 33.9’ E and 320 51’’ 29.1’ E. The area is underlain by late Precambrian metasediments and metavolcanics intruded by older and younger granites. The aim of the study is to determine the contents of the rare metals Sn, W, Nb and Ta in the alkaline, post- orogenic igneous complexes of J. Sultaniyate, J. Ras Ed Dom and J. Abu Dom. The methodology includes office works, mainly the survey of the previous literature and processing of landSat imagery. This was followed by ground truthing of the results obtained from the processed images; field updating of the available geological maps, together with the collection of rock hand specimens and minerlaized chip samples. 20 samples have been analyzed because of limited budget for analysis. Subsequently, petrographic and geochemical analysis by ICP-MS method were carried out in NARGETEST Lab., Turkey and in the laboratories of the Geological Researches Authority of Sudan, Khartoum, before writing up of the final thesis. The high ratios of K/Rb and K/Ba is 540 and 130, respectively suggest late stage progressive fractional crystallization and probable mineralization. Despite of that the high content of the elements Ba and Zr, reaching 390 and 404 ppm, respectively and the relatively low Rb and Sr, namely 94 and 111ppm, respectively are not in faviour of progressive fractionation which would allow concentration of the rare metals Ta, Nb, Sn and W. The Sporadic distribution of Rb, Cs, Li, B and Sn reinforces the lack of progressive fractionation. To conclude, the present results necessitate further detailed sampling of the post-orogenic ring complexes in the area in order to decide on their economic potential of the rare metals. المستلخص تقع منطقة الدراسة في وسط صحراء بيوضة شمال السودان. يحدها خطا العرض 170 52 "18.2" و 18.0 16 "09.9" شمالاً ؛ وخطا الطول 330 00 "33.9" و 320 51 "29.1" شرقًا. تغطي المنطقة مجموعة صخور الاساس في العصر ما قبل الكمبري المتأخر و تشمل الصخور الرسوبية و البركانية المتحولة المقطوعة بمجموعتي صخور الجرانيت القدم و الجرانيت الحدث. الهدف من الدراسة هو تحديد محتوي الفلزات النادرة (Nb and Ta W,, Sn) في التجمعات النارية القلوية ما بعد التجبل في كل من جبال سلطانيات و رأس الدوم و أبودوم. تتضمن منهجية البحث الأعمال المكتبية ،مثل امسح الدراسات السابقة ومعالجة صور الاقمار الصناعية. تبع ذلك االتحقق من نتائج دراسات صور الاقمار الصناعية المعالجة, ، التخريط الجيولوجي وجمع العينات الصخرية اليدوية و كسفات الصخور المتمعدنة. تم تحليل عدد 20 عينة بسبب الميزانية المحدودة للتحليل. تمت دراسة مجهرية الصخور و التحليل الجيوكيميائي للعينات المتمعدنة بطريقة ICP-MS في معمل NARGETEST بتركيا و معامل هيئة البحوث الجيولوجية في السودان . و ذلك قبل الكتابة النهائية للاطروحة. النسب العالية من K / Rb و K / Ba و التي بلغت 540 و 130 ، على التوالي تشير إلى مرحلة متأخرة من التبلور الجزئي التقدمي والتمعدن المحتمل. و على الرغم من ذلك فإن المحتوى العالي من العناصر Ba و Zr البالغ 390 و 404 ppm علي التوالي، والمنخفض نسبيًا في Rb و Sr البالغ 94 و 111 ppm على التوالي ، غير مواتية للتجزئة التقدمية التي تسمح بتركيز الفلزات النادرة ــــــــــــــــــــــــــــــــ Ta و Nb و Sn و W. كذلك التوزيع العشوائي لـ Rb و Cs و Li و B و Sn لا يدعم التجزئة التقدمية. في الختام تستلزم النتائج الحالية أخذ عينات تفصيلية إضافية من تجمعات السدود الدائرية ما بعد التجبل في المنطقة ، من أجل تحديد إمكاناتها الاقتصادية المحتملة للفلزات النادرة.
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ItemGeology, Geochemistry and Gold Mineralization Southeast Wadi Halfa Town - Northern State - Sudan(University of Khartoum, )This study was carried out 53 km southeast of Wadi Halfa Town, Northern State, Sudan. It is aimed to investigate recourse behind the mineralization and to establish prospecting criteria in order to identify the gold mineralized zones, mineral associations and the processes that controlled the mineralization. Furthermore, priority areas for further exploration were also delineated. The methodologies adopted include processing of Landsat images, field geological mapping, sampling of rocks, mineralized zones, soils, clays and alluvial deposits, study of thin and polished rock sections and geochemical analysis of 25 samples from the mineralized rocks, quartz and the altered wall rocks. The analytical methods include inductively coupled plasma (ICP) and ICP aided by mass spectrometry (ICP-MS) analysis which is accredited for gold analysis. Field and petrographic studies of rock thin sections revealed that the study area is underlain by a Pan-African assemblage of low - to medium- grade metavolcanics and metasediments that were intruded by I-type granitoids and unfoliated, A-type granites. The layered sequences have been subjected to folding, faulting, shearing and metamorphism of the Pan-African tectonothermal orogeny. Dykes of variable composition and quartz veins intrude most of the previous rock groups. The Nubian Sandstone Formation rests unconformably on these rocks. Wadi alluvium and sand dunes represent the recent superficial deposits. The metavolcanics and associated older granitoid rocks reveal sub-alkaline geochemical affinities that evolved in a volcanic-arc environment. The geochemical analyses by (ICP-MS) methods confirmed the presence of gold in all 25 samples collected from the quartz veins and sheared rocks. The gold is found associated with sulphides in quartz veins, sheared and hydrothermally altered ferruginous quartzites, granitoids and other metavolcanic- metasedimentary sequences. 25 samples were analyzed by inductively coupled plasma (ICP) for the trace elements of which. Strong correlations with Au are shown by the pathfinders Ag (0.895 correlation value), Bi (0.856), Mo (0.921), Re (0.901), Te (0.91) and W (0.912). Moderate correlation values are exhibited by Rb (0.4), Ta (0.366) and Zr (0.4); while Sb shows a weak correlation value of 0.135. Furthermore, the multi-element geochemical data show negative relationship between Au and As, Hg, Zn, and Cu. Also, copper has strong positive correlation value (0.91) with zinc and nickel (0.816). Other element pairs which have strong positive correlation values include As- Ag - Bi, Ag - Mo, Ag - Rb, Ag - Te. Moderate positive correlations are revealed by the elements pairs As-Sn, As-U, U-Zr, Cr-Hg, Bi-Ge, Co-Sc, and Y-Zr. To conclude the geology of the study area is favorable for gold mineralization as for as the rock type and the shear deformation are concert. The bearable correlation can be used as prospecting criteria for gold in the study and environs. Also the basic and intermediate volcanic have been subjected to hydrothermal solutions produced by the associated granitic intrusions. These mineralizing solutions increased the gold concentration and were redeposited the mineral in preferred shear zone striking E-W and WNW-SSE; while the shear zone which strike NW-SE and NNE-SSW are non-productive. Areas of gold mineralization are prioritized and are recommended for exploration such as trenching and pitting. Drilling should follow suit in selected areas, depending on the results of the analyses.
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ItemGeological and Geochemical Study of Granulite and Related Rocks in Sabaloka Inlier, North of Khartoum(University of Khartoum, )A geological and geochemical study have been carried out in the Sabaloka inlier, north of Khartoum between latitudes 16⁰ 05`- 16⁰ 25` North and longitudes 32⁰ 35′ - 32⁰ 55′ East. Granulite facies rocks of Pan-African age are exposed within retrogressed gneisses and migmatites of amphibolite facies and are intruded by older granites coverd by the Cretaceous sandstone, they represent deep seated metamorphism in the thickened crust. The older granites are S- type and divided into anatectic granite, syn- tectonic granite and post tectonic granite, and all of the older granites have same geochemical character. The geochemical results obtained show that the enderbitic and calcsilicate granulite rocks are meta- igneous in origin while the semipelitic gneisses are meta- sedimentary in origin. The pressure and temperature estimated from the mineral assemblages of the granulite rocks suggested to be between 6.5 – 8 Kb and 700- 850⁰C, and the retrogression to the amphibolite facies is estimated at 4 -5.5 Kb and 400 - 550⁰C.Field observation indicated that the study area contains three phase of deformation, the first phase is isoclinal fold, the second phase is similar recumbent fold and the third phase is open concentric fold. As a result of field relations, Pressure, Temperature conditions and geochemical study, the Sabaloka represent a continental margin collided with an island arc assemblage to the east in Red Sea Hills (Arabian Nubian Shield) and formed the granulite deep in the crust which uplifted by the isostatic uplifting.
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ItemGravity and Electrical Methods for Studying the Groundwater Associated Structures in the area of Um Rimita (White Nile State), Sudan(University of Khartoum, )A Bouguer gravity anomaly map and sixty two (62) Vertical Electrical Sounding (VES) measurements in the area west of the White Nile between Latitudes 14◦40-15◦35 N and Longitudes 32◦10-32◦30 E are used to investigate the geology and subsurface structures of the region.The aim of the study is to obtain the general configuration of the Basement Complex and to provide information about the nature and structures of the formations as well as to assess groundwater associated problems. Measurements of electric resistivity were carried out along selected profiles superimposed on the Bouguer gravity map. The geoelectric cross-sections and the gravity models are constructed along the same profiles to disclose sediment variation and confirm geometry of the subsurface geology. The Basement Complex is affected by several step normal faults which make undulations on its surface where the sediments are deposited with various thickness. The main aquifer in the area is represented by the Nubian Sandstone Formation. The major depression in the study area (Sheikh el Sidig) is oriented in a NW-SE direction. A major fault bounded uplift is recorded in the west of the area. The delineated basins in the study area are relatively shallower than these basins of the Gezira and the White Nile Rift. Five (5) gravity profiles are drawn, generally perpendicular to the major axis of the structures in the area. These are lately used for quantitative interpretation. A Graph-Model Computer Software is used for gravity modeling which is based on line-integral method of computation. The electrical field curves are modeled with the aid of Resix (Interpex 1993). The interpretation results are presented in a form of geo-electrical sections. A subsurface structural map is proposed showing inferred sedimentary basins, fault troughs and uplifted Basement blocks. The basins are believed to be fault-controlled and developed by extensional tectonics. As for the mechanism and cause of faulting, the area is considered as part of the Central Sudan rift system which had been subjected to several tectonic events since Early Cambrian to Tertiary times.