STRATIGRAPHY AND PALEONTOLOGY

A CONTRIBUTION TO THE LITHOSTRATIGRAPHY OF THE PLIO-PLEISTOCENE SUCCESSION IN THE AREA SOUTHWEST OF WADI EL-NATRUN, NORTH WESTERN DESERT, EGYPT

Wanas, H. A., Khalifa, M. M. and Mousa, F. A.

Geology Department, Faculty of Science, Menoufia University, Egypt

Four Plio-Pleistocene lithostratigraphic rock units have been recorded in the area southwest of Wadi El-Natrun, north Western Desert of Egypt. These rock units are from base to top: Meikheimin (Early Pliocene), El-Muluk (Late Pliocene), Hagif (Late Pliocene), and Qataji (Plio-Pleistocene) formations. The Meikheimin Formation is made up of conglomeratic, calcareous sandstones and sandy to gravelly limestones. It unconformably overlies the Lower Miocene Raml Formation. The El-Muluk Formation is subdivided into three informal units (lower, middle and upper). The lower unit is dominated by a cycle of chalky limestones and carbonaceous mudrocks. The middle unit is composed of intercalated succession of fine-grained sandstones, sands and mudrocks with few siltstones. The upper unit consists mainly of mudrocks, shales, claystones, sandstones, gypsum and thin burrowed limestone bed. The Hagif Formation is subdivided into two informal units including: lower clastic unit and upper carbonate-clastic unit. The clastic unit consists of a succession of sandstones, siltstones and grey shales. The carbonate-clastic unit is made up of an interbedded succession of sandy, glauconitic, evaporitic limestones, shales and evaporites. The Qataji Formation is predominantly composed of pink colored, laminated, oncoidal and non-fossiliferous carbonates. It is unconformably overlies the Hagif Formation.

Key words: Lithostratigraphy, Plio-Pleistocene, Wadi El-Natrun, Western Desert, Egypt.

A CONTRIBUTION TO THE LATE EOCENE SIRENIAN FOSSILS OCCURRENCES AT THE NORTH OF LAKE QAROUN, FAYOUM, EGYPT

Abu El-Kheir, G. A.

Geology  Department, Faculty of Science,  New Valley University

gebely200@scinv.au.edu.eg         

 ABSTRACT

The present studying focuses on the geological significances of the uniqueoccurrences of the Late Eocene sirenian skeletons in the uppermost part of Qasr El Sagha Formation at the north of Lake Qaroun, Fayoum Depression, Egypt.The present work explains the relationship between the habitats of the sirenians and the depositional environment of the bearing layer, in addition to the taphonomic conditions of the Sirenian carcasses until the embedding of the bearing layer.Qasr El Sagha Formation is divided into two main Members, Temple Member and Dir Abu LifaMember.Dir Abu LifaMember of Qasr El Sagha Formation is the most important succession of the occurrences of Late Eocene Sirenians at the north of Lake Qaroun, Fayoum.

The Sirenian skeletons are distributed in successive vertebrate horizons, having different modes of preservations, affecting by the depositional environments.

The most important horizon of bearing Sirenian skeletons is located in the uppermost layer in Dir Abu LifaMember that represents the unconformable contact with the overlying Gebel Qatrani Formation. This horizon contains some other associated fossils such as turtles, crocodiles, shark teeth and abraded invertebrate shells and gastropods

Based on detailed field study and microscopic thin section investigation of the Sirenian skeletons, taphonomic profile and its sedimentological and biological significances were discussed.

The study indicated that the Sirenia were lived in shallow restricted lagoons, where high concentrations of herbs nutrients such as algae and others. They derived after death by some storm high currents to the nearshore area of the lagoon, highly affecting by the driving currents.

The present work will not only increase ourknowledge about the Eocene Sirenia but also will improve understanding of their habitats and the conditions of the surrounding paleo-environment.

Key words: Qasr El Sagha, Dir Abu LifaMember,Late Eocene, Eosiren, Sirenian and  Fayoum.

INDUSTRIAL ROCKS   

MITIGATION OF CLAY SWELLING BY USING NANO-COATING TECHNIQUE NILE DELTA AREA, EGYPT

El Shayeb, H a., Noah, A.b, Doaa .M b  Eid, M. a

a  Geology Department – Faculty of Science , Menofya University

b  Egyptian Petroleum Research Institute (EPRI), Nasr City, Cairo, Egypt

Shales make up about three fourths of drilled formation and over 90% of the wellbore instability problems that occur in shales. Even though shale stability has been studied for several decades, it stills a serious problem in not only the petroleum industry but also in the mining and construction industries. Before any measures are taken to address this problem, it is crucial that potentially problematic formations and the mechanisms of wellbore instability be identified. Once the mechanisms are understood, well planning, drilling fluid design, and drilling operation strategies can be implemented to ensure wellbore stability This study aims to inhibit shale swelling process throughout additive potassium chloride (KCl) and nanoparticles oxides to water-based mud and using linear swell meter and Shale compact disks. Swelling of shale cuttings increased in direction Shale x<y<z. The inhibition of swelling of these shale cuttings using 1-4% KCl achieved decreasing in swelling ranged from 17% at 2% (shale x), 22% at 3% (shale y) and 30% at 4% (shale z). Meanwhile, the effect of nanoscale oxides as inhibitor was great compared with KCl. These nanoscale oxides caused dramatic decrease in swelling of shales. Nanoscale SiO2 achieved almost 42% inhibition in swelling of shale at 0.25% in contact with OCMA bentonite. Meanwhile, ZnO and Cobalt nano particles caused less swelling decreasing at the same concentration 0.25% ranged between 25% and 37% ZnO and TiO2 respectively

Key words: Nano-Particles, clay swelling, Linear Swell Meter, inhibition

MINERALOGY AND GEOCHEMISTRY  

CONTRIBUTIONS TO THE ORIGIN OF URANIUM MINERALIZATION HOSTED BY THE DIFFERENT SEDIMENTARY LITHOFACIES OF UM BOGMA FORMATION, SOUTHWESTERN SINAI, EGYPT

Shata, A. A. 1, Mostafa, A. 2, Tolba, A. S.2, Nasr, M. M 1 and Serag El Din, H. S. 1

1. Nuclear Materials Authority (NMA), P.O. Box: 530 El Maadi, Cairo, Egypt.

2. Department of Geology, Faculty of Science, Al Azhar University (Assuit Branch), Assuit, Egypt.

This work was carried out to the Paleozoic different sedimentary lithofacies of Um Bogma Formation at Southwestern Sinai. These sedimentary lithofacies controlled the uranium mobilization in the studied Dabbet Abu Thor and El Allouga localities. The present uranium minerals in the radioactive sedimentary lithofacieswere detected by using X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) investigations.  The present study reveals the intimate relations between the laterite-bauxite lithofacies and their hosted uranium mineralization.The origin of the detected uranium minerals inferred as the result of diagenetic and biogenic processes included in surficial processes.The detected uranium minerals include uranium vanadates, phosphates, sulphates, carbonates and molybednates categories. The last uranium group (uranium molybednates) is related mainly to the gibbsite bearing lithofacies broadly exposed at Dabbet Abu Thor and condensed in faint and tiny exposures at El Allouga locality.

Key words: Uranium minerals, gibbsite, black shale, origin, Um Bogma, lithfacies, Allouga and Dabbet Abu Thor.

GEOCHEMICAL AND MINERALOGICAL STUDIES OF THE JURASSICCRETACEOUS SEDIMENTS IN NORTHERN SINAI, EGYPT

Lotfy, M. M.1 and Abdel Gawad, E 2  

1 Exploration Dept., Egy. Petro. Res. Inst. (EPRI),

2 Geology Dept, Fac. of Sci., Al-Azhar Univ., Egypt

The area comprising the northern Sinai is an important hydrocarbon province in Egypt, but the origin of the hydrocarbons and their migration is not fully understood. In this paper, we evaluate organic source facies in order to improve our understanding of the regional petroleum system. Organic-geochemical and petrographic analyses of rock samples ranging in age from Early Jurassic to Cretaceous were used in this study. Most of the samples studied had moderate to high TOC contents, and kerogen was a mixture of Types II and III with a wide range of petroleum generation potentials from very poor to very good. Pyrolysis-GC of Kerogen pyrolysate (PII) fingerprints of the ten extracted samples analyzed is all relatively similar and none are typical of good quality oil-prone source rocks. Some differences in quality are observed between the samples, which would result in generation of slightly different hydrocarbon types upon maturation or example, the sample at depth 3840 m is most typical of a poor quality, gas prone. Clay minerals are the main agent of adsorption which is consistent with the clay-rich lithology of the source rocks.  SEM microscope and X ray diffraction analytical tools shows that the early stage is characterized by formation of clay minerals and quartz overgrowth. The second stage was dominated by detrital minerals of illite, montmorillonite, Fe oxides and carbonate minerals precipitated.

Key words: Pyrolysis-GC; geochemistry; Jurassic; Kerogen; Sinai and Egypt.

HEAVY METALS CONCENTRATIONS IN WATER AND SOIL OF AL-HAMOUL AREA – KAFR EL-SHEIKH. NILE DELTA, EGYPT

Abu El-Hassan, M. M.1, Khalifa, M. M. 1, Moghanm, F. S. 2 and EI Sherif, R. E. 2

  1) Department of Geology, Faculty of Science, Menoufia University, Shiben El Kom,

 2) Soil and Water Department, Faculty of Agriculture, Kafr El Ssheikh University

Heavy metals concentration in water is one of the major problems faced worldwide and requires attention because heavy metals above their normal ranges are extremely endangered for plant, animal and human life. It was therefore of interest to conduct study to estimate concentration of heavy metals in soil, water in Kitchner drain of Al-Hamoul region. Six water samples and 12 soil samples have represented six sites covering the studied area for analyses by inductively coupled plasma-optical emission spectroscopy (ICP) Concentrations of heavy metals and Physico- chemical parameters in soil and water compared with World Health Organization (WHO) standards. Physico-chemical parameters such as pH and electrical conductivity in soil and water were also analysed. PH and electrical conductivity of all water samples was recorded below the normal range set by WHO. PH of all soil samples was recorded below the normal range set by WHO. Heavy metals in soil analyzed and resulted high concentration Cd, Ni, Fe, and Cr with mean values 22, 256, 7342 and 29.6 mg/kg respectively. Heavy metals in water of Kitchner drain analyzed and resulted high concentration Cd, Fe, and Cr with mean values 0.493, 3.561 and 0.579 mg/kg respectively and normal value of Ni mean value 1.342 mg/kg. High concentration of Cd, Ni, Fe, and Cr in soil. High   concentration   of   heavy   metals   in   soil   and   water   are   emergency   alarm   for community health and the recommendation to improve water quality of Kitchner drain.

Keywords; Soil, Water, pH, pollution, Heavy metals

WADI HAMMAD LEAD-OLDMINE DOKHAN VOLCANICS, NORTHEASTERN DESERT, EGYPT:A POTENTIAL SOURCEFOR URANIUMMINERALIZATION, GEOLOGICAL ANDSTRUCTURAL IMPLICATIONS

El Sundoly, H, Azab, I.* and .Khamis, H.

Nuclear Materials Authority, Cairo, Egypt

The late Proterozoic Dokhan Volcanics (700-650 Ma) represents an important rock unit that is widely distributed at the northern part of the Eastern Desert of Egypt. Wadi Hammad area is covered in its main part by different varieties of volcanic rocks related to the Dokhan type. The Pb-old mine location is famous with well spectacular stratified section of inter-layered lava flows and pyroclastics that intruded by porphyritic granites at its base. The structural and tectonic analysis of the area revealed that there are three compressional phases and one extensional phase. The detailed radiometric investigation for the volcanic succession revealed that there are two lithologically and structurally controlled radioactive anomalies within the ignimbrite above the Pb-bearing quartz vein which make it a potential source for uranium mineralization.

Key words: Uranium Mineralization, Geology, Volcanic, Dokan Volcanics, Quartz-Vein, Pb-Old Mine, Eastern Desert, Egypt

GEOLOGICAL CHARACTERIZATION OF QUARTZITES, SOUTHWEST GABAL UMM RIHIYAT, NORTH EASTERN DESERT, EGYPT

Shahin, T. M

 Geology Department, Faculty of Science, Al-Azhar University Cairo, Egypt

The Oligocene sedimentsof southwest Gabal Umm Rihiyatcomprise pebbles of quartz, chert, flint, and quartzite, that were affectedbyhydrothermal solutions and basaltic eruptionsduring Late Oligocene-Early Miocene time. In this study, field geology, petrography, and geochemical data were utilized to determine the genesis of quartzites. Petrographic analysis reveals that the quartzite is fine- to coarse, rounded to sub-angular, and moderately-sorted quartz grains with subordinate amount of mica, zircon, and iron oxides minerals. Quartz is the predominant authigenic overgrowth present as a matrix and sometimes hematite.Geochemically, the quartzite is considered mature, consists predominantly of quartz arenites, and have a high SiO2 content, up to 90.81wt%. All samples have SiO2/Al2O3> 10 (average ~43), which indicates high maturity consistent with the petrographic results. The CIA values of the quartzite suggest low to moderate chemical weathering conditions under humid climate. The major and trace element ratios diagrams suggest that these quartzites were predominantly derived from the felsic sources, formed in passive continental margin setting

Key words: Quartzite, geochemistry, Oligocene, Northern Eastern Desert, Egypt. 

COMPARATIVE PETROGRAPHIC AND GEOCHEMICAL STUDIES ON THE UPPER CRETACEOUSOIL SHALES IN GEBEL DUWI AREA, RED SEA COAST, EGYPT

Saeed, Z. M. 1*, El-Kammar, A. 1 (RIP.), El-Shafeiy, M. 1, and Salem, A. M. 2

1. Geology Department, Fac. of Sci., Cairo Univ., 12613, Giza, Egypt

2. Petroleum Engineering Dept, Fac. of Petroleum and mining Engineering, Suez Univ., Suez, Egyp

During the past 70 years, the Upper Cretaceous oil shales in Gebal Duwi area were dumped as ahuge amount of trash out of the phosphorite mines. Based on serveral previous studies, these oil shales were evaluated to generate commercial quantities of hydrocarbons when subjected to adequate generation conditions. Core, dumped, weathered and surface-exposed samples were collected from the oil shales that represent the most productive horizon for organic carbon. These oil shales constitute the stratigraphic interval representing the contact between the Duwi and the overlying Dakhla  formations. The samples were subjected to serveral petrographic and organic geochemical examinations in order to determine their lithologic, organic matter content, thermal maturity characteristics,Total organic carbon (TOC) and oil yield values. The results obtained show that, based on the quality and quantity of their organic matter contents. Consequently, these oil shales have high values of oil yield. They are considered as a very good hydrocarbon source rocks. These oil shales are in immature – marginally mature stage and at the beginning of the generation stage..

Keywords: Egypt, Red Sea Coast, Gebal Duwi area, Upper Cretaceous, Oil Shales, Petrography, Organic Geochemistry.

CHARACTERIZATION OF SOME EGYPTIAN WHITE SAND AND DUNES FOR UTILIZATION AS HYDRAULIC FRACTURING SAND FOR TIGHT OIL WELL LAYERS

Wahab, G.M.A. and Ibrahim, G. A.

Egyptian Petroleum Research Institute, Exploration Department, Nasr City, Cairo, Egypt

Huge quantities of pure silica sand are located along the Red sea coast; Sinai and Eastern Desert can be suitable to be fracturing sand. Frac. sand is naturally occurring with high silica content 95%, utilized as a proppant during hydraulic fracturing of tight oil and gas reservoir wells to maximize production from low permeability sandstones, shale and carbonate rocks.

This research aims to providing the characteristics of Wadi Dakhale white sand and sand dune occurrence in the Bahariya Oasis Road (Karama oil field) to be utilized as frac sand. The paper is focusing on study the occurrence, physical, chemical, and mechanical properties of silica sand at Wadi Dakhal and Bahariya Road. The assessment testing of the studied samples revealed, good results, verifying the standard requirements, where SiO2 content is 95% in Karama field and 99 % in Wadi Dakhal, crush resistance 5500 – 6500 psi, maximum turbidity is 2%, and the grain roundness are rounded to sub rounded,which complying with ISO 13503 and grain size distribution range 30/50 to 40/70 (710 um to 210 um) grading

Key words: Frac sand; Hydraulic fracturing; Silica sand; Dune ; Wadi Dakhale; Bahariya Oasis

GEOLOGY, GEOCHEMISTRY, RADIOACTIVITY AND EVALUATION OF RADIOLOGICAL HAZARD EFFECTS OF HUMR WAGGAT AND ABU DIAB GRANITES, CENTRAL EASTERN DESERT, EGYPT

El Afandy, A. H., El Shaib, G.B. and Moghazy, N. M.

Nuclear Materials Authority, Cairo, Egypt. Box, 530 El Maadi

 This work discusses the geology, geochemistry, distribution of the natural radionuclides and assesses the radiological hazard resulting from Humr Waggat and Abu Diab granites, Central Eastern Desert, Egypt. Humr Waggat granitic mass forms a circular body elongated in a NW-SE direction dissects by Wadi El Faliq, which separated this granitic mass into two parts and occupied by a vast sandy plain with some scattered islets of granites and some weathering boulders and block products. Petrographically, this granitic mass can be categorized as alkali feldspar granites, syenogranites and monzogranites. Gabal Abu Diab forms an oval- shape granitic mass elongated in a NW-SE direction and surrounded from the western and southern side by a vast sandy plain. These granites can be categorized as syenogranites and monzogranites. The granitic masses of Humr Waggat and Abu Diab intrude serpentines ,metasediments ,metagabbro, and granodiorites with intrusive contacts.

Geochemically, the studied granites are true granites in composition originated from calc-alkaline magma. They are predominantly have peraluminous to slightly metaluminous nature and considered as C-type granites. The magma of the studied granites was generated from crustal material of intermediate composition and developed in post-collision tectonic setting by partial melting of crustal materials and the crystal fractionation was the predominant process during magmatic differentiation.

The monzogranite phases in Humr Waggat and Abu Diab are the least uranium contents and the syenogranites phases in the two masses are the highest uranium contents. Also, a magmatic and post-magmatic condition play an important role in the distribution of uranium in the studied granites. The uranium and thorium contents are encountered in refractory minerals as sphene, fluorite, allanite, apatite, and zircon.

Keywords:the radium equivalent activity (Raeq), gamma activity index (Ig), alpha activity index (Iα), external hazard index (Hex), internal hazard index (Hin), external absorbed dose rate in outdoor (Dout) and indoor (Din), annual effective dose (AEDE), annual gondal dose equivalent (AGDE) and excess lifetime cancar risk (ELCR) are calculated. The studies concluded that all the environmental impacts dose rate values in the granitic rocks of Humr Waggat and Abu Diab are lower than the public permissible values and they are within the safety range for the public and not danger on the workers. Then,these rocks can be used as a building and ornamental materials.

GEOLOGY, GEOCHEMISTRY, RADIOACTIVITY AND MINERALOGY OF THE GRANITIC ROKS AT EL MISSIKAT-UM RAKHAT DISTRICT, CENTRAL EASTERN DESERT, EGYPT

El Afandy, A.H.1, Ellawa, H.A 2, El Rakaiby, M.M 1, Omar, S.A.1 and Salim, F.A.1

1- Nuclear Materials Authority, P.O. 530, El-Maadi, Cairo, Egypt.

2- Geology Department, Faculty of science, Minufiya University, Egypt.

Geochemically, the studied granites are true granites in composition and characteristics, originated from calc-alkaline magma. They are predominantly having peraluminous to slightly metaluminous nature and considered as M-type granites. Accordingly, the tonalities and granodiorites are highly fractionated I-type granites while the monzogranites and syenogranites are belonging to A2 granites which represents magmas derived from continental crust or under-plated crust that has been subjected to a cycle of continent- continent collision or island-arc magmatism.  The magma of the studied tonalites and granodiorites was generated from crustal material of basic composition and the monzogranites and syenogranites were generated from intermediate composition developed in Within Plate tectonic setting by partial melting of crustal materials. The crystal fractionation is the predominant process during magmatic differentiation. The tonalite and granodiorite phases are the least uranium contents while the monzogranite and syenogranite phases are the highest uranium contents. The red and black silica veins are the highest radioactivity and contain uranium minerals, Also, a magnetic and post-magmatic condition play an important role in the distribution of uranium in the studied granites. The uranium and thorium contents are encountered in uranium and thorium minerals as well as radioactive bearing minerals as uranophane, uranothorite, thorite, columbite, xenotime, zircon, monazite, sphene, fluorite, allanite, and apatite.

Keywords: monzogranites, syenogranites, uranophane,, uranothorite,, thorite, and, columbite, xenotime

GEOCHEMICAL CHARACTERISTICS AND THE ORIGIN OF KALABSHA KAOLIN DEPOSITS, SOUTHWEST ASWAN, EGYPT

Sharaka, H. K. (1), Abd El-Moghny, M.W. (2), El-Desoky, H. M. (2), Abdel Hafez, N. A. (2), and Abouellaban, S. A. (1)

(1) Egyptian Mineral Resources Authority, Abbassiya, Cairo, Egypt

(2) Geology Department, Faculty of Science, Al-Azhar University, Nasser City, Cairo, Egypt

Kaolin samples were collected from Wadi Kalabsha, southwest Aswan district, Egypt to study their geochemical characteristic and geochemical composition. The Lower-Upper Cretaceous succession of the studied area consists of Lake Nasser, El-Burg, Nubia group (Abu Aggag, Timsah), and Kiseiba formations. Geochemical study revealed that kaolinite is the main constituent of clay minerals, which was derived from chemical weathering of Al-rich source rocks and complete leaching under warm, semi-arid climatic conditions. Meanwhile, non-clay minerals are represented by quartz and trace minerals of anatase. The high contents of Al2O3, SiO2, LOI, and low contents of MgO, Cl, SO3, P2O5 as well as the depletion of alkali elements (e.g. CaO, K2O, and Na2O) that are attributed to high kaolinite content in these samples. Furthermore, the abundance of Cr, Ti, Zr, and V, and the absence of illite and chlorite suggested a mixture of medium to high-grade metamorphic and granitic rocks as a source rock. The studied kaolin samples were deposited in oxidation or supergene continental conditions, arid to semi-humid climatic environmental condition zone due to intensive chemical weathering and high chemical maturity. Besides, all the studied kaolin samples were derived from the per-aluminous source rocks.

Keywords: Kaolinite; Geochemistry; Protoliths; Kalabsha; Southwest Aswan; Egypt.

STRUCTURE GEOLOGY

TECTONIC EVENTS AT GABAL HAMRAT AL JIRJAB AREA AND ITS RELATION WITH RADIOACTIVITY OF THE AREA, NORTH EASTERN DESERT, EGYPT

EL Sundoly, H.. I. and. Waheeb, A. G. *

 Nuclear Materials Authority, Cairo, Egypt.

Detailed structural study for Gabal Hamrat Al Jirjab area was carried to clarify the sequence of phases of deformation that affected the granitic rock and to determine the main phase that responsible for the distribution and localization of uranium minerals in the area.

The area has undergone a long-lasting tectonic history involving five main tectonic events, each event is beginning with compression (CP) then extension (EXT) deformation, affected the alkali feldspar granite of G. Hamrat Al Jirjab area. These events listed from the oldest to the youngest as the following: - first event is {ENE-WSW(CP), NNW-SSE (EXT)},second event is {E-W (CP) , N-S ( EXT)} , third event is {NE-SW to NNE-SSW (CP), NW-SE to WNW-ESE (EXT) }, fourth event is {WNW-ESE to NW-SE (CP), NNE-SSW to NE-SW (EXT)} and the fifth and final event is {NNW-SSE to N-S (CP), ENE-WSW to E-W (EXT)}.

Structural analysis revealed that the main extensional phase allowed the mineralized hydrothermal solutions to migrate upward is N-S (EXT) phase of deformation. Tension joints revealed that area subjected to extensional phases of deformation trending WNW-ESE, NNE-SSW and N-S directions; as well as, the shear joints indicated that the area are subjected to compressional phases of deformations trending NNE-SSW, NE-SW, E-Wand WNW-ESE directions and extensional phases trending NE-SW, ENE-WSW, E-W, NNW-SSE and WNW-ESE directions. 

Key words: tension and shear joints, stress analysis, uranium, and G. Hamrat Al Jirjab granite.

RESOLVED SHEAR FOR THE URANIUM MINERALIZED FAULT CONTACTS AT GABAL ABU HAMR AND GABAL GATTAR, NORTHERN EASTERN DESERT, EGYPT

. Waheeb , A. G *

Nuclear Materials Authority, Cairo, Egypt.

*Corresponding author. E-mail address: anton_oon@yahoo.com

The uranium mineralization can be easily seen along the structural contact between the metavolcanics and the younger granite at G. Abu Hamr. This occurrence is recorded along a major fault trending NNE-SSW to NE-SW .Also, at G. Gattar the mineralization occur along the contact between the Hammamat sediments and the younger Gattarian granite and found along a major fault trending ENE-WSW to NE-SW direction (mostly trending NE-SW direction). This trend is parallel to one of the major shear zones that have been dominated at the Egyptian basements (Qena-Safaga and Idfu –Marsa Alam shear zones).

The determination of the direction and sense of resolved shear stress for the two mineralized fault contacts indicate that it is directed NE-SW related to the youngest Red Sea- Gulf of Suez rifting extensional force which affected Egypt since the Tertiary time. So that, we can state that the Red Sea rifting has a great effect on the investigated areas and allowed the uranium bearing hydrothermal solution to migrate along the structural contact between the younger granites and their surrounding rocks .The mineralization are concentrated along and adjacent to these faults contact

Key words: Resolved shear, uranium, structural control, G.Abu Hamr and G.Gattar. 

PALEOECOLOGY

THE GEO-ENVIRONMENTAL CHARACTERISTICS OF THE DOWNSTREAM OF WADI ALLAQI BIOSPHERE RESERVE ON THE LIGHT OF THE CLIMATIC CHANGES.

Mekki, M. S. * (1), El-Mezayen, A. M. (2), El-Desoky, H. M. (3)and Khalil, A. E. (4)

(1) Egyptian Environmental Affairs Agency (EEAA), Nature Conservation Sector (NCS),

(2) Professor of Geology, Geology Department, Al-Azhar University, boys, Cairo,   

(3) Professor of Geochemistry, Geology Department, Al-Azhar University, boys, Cairo,

 (4) Professor of Geochemistry and Mineralogy, National Research Centre, Cairo

The erection of the Aswan High Dam resulted in the creation of a great lake and forty two branches – commonly termed khors - which were created afterwards. The formation of the huge reservoir of Aswan High Dam produced remarkable changes in the ecology of the local desert ecosystem. Inundation from the lake has penetrated through the wadis deeply into the hyper arid environment of the Eastern Desert. The accumulation of water after the construction of the High Dam participated in changing the landscape geomorphology of the shorelines of the southern part of the River Nile in Egypt.

The current article focuses on the overall geomorphological outlook of the northern downstream part of Khor Allaqi. The impacts of the climatic changes reflected in the transgression and regression of the water body inside Wadi Allaqi due to the amounts of the rainfall on the Ethiopian plateau as well as the major meteorological parameters and the associated vegetation cover have been  assessed and investigated. The vegetation cover decreased about 12.9 ha in the period from 1960's to 2016 which is attributed to climatic changes

Keywords:The Geo-environmental characteristics; Wadi Allaqi Biosphere Reserv; The climatic changes; Global warming; Vegetation cover

REMOTE SENSING

IGNEOUS ACTIVITY AROUND KHARIT BASIN USING REMOTE SENSING DATA ANALYSIS, SOUTH EASTERN DESERT, EGYPT

Abuelella, I. 1, Sakran, S. 1, Khalifa, K. 2, and Abdelhalim, A. 1

1 Geology Department, Cairo University, Faculty of Science, Giza, Egypt.

2 Agreements and Exploration Department, GANOPE, Cairo, Egypt.

Kharit area lies at the southern part of the Eastern Desert in Egypt, where the Phanerozoic rocks dominated with reasonable volcanic igneous rock.  The analyses applied on ASTER imagery data sets led to identification of multiphase of igneous activity and highlight new areas recorded igneous activity. The igneous activity in the study area are described either ring complexes (Zargaat El-Naam and Tarbtei North) or dispersed basaltic intrusions. The ring complexes occur along contact areas between Precambrian basement complexes and Mesozoic sedimentary rocks. The dispersed basaltic intrusions appeared in NW alignments within sedimentary rock or near contact zone between Precambrian basement complexes and sedimentary rocks.

Keywords: Igneous activity; ASTER; Kharit Basin; South Eastern Desert.

MANGANESE ORE INVESTIGATION USING REMOTE SENSING AND GIS TECHNIQUES, IN ABU SHAAR EL QIBLI AREA, EASTERN DESERT, EGYPT

Mahdy, A. (1) *, Yehia, M. A. (2) and Abdelmalik, K.W.(3)

(1)       Egyptian Mineral Resources Authority

*  Corresponding author. E-mail address: mahdyahmed707@gmail.com

(2 and 3)  Geol. Dept., Fac. of Science,  Ain Shams University, Cairo, Egypt

The present study aims to investigate the use of spectral signature   of multispectral Landsat-8 data in geological investigation of mineral resources, besides petrographic and chemical analysis as well as filed verification to investigate the occurrence of manganese deposits of Abu Shaar el Qibli Area, Eastern Desert, Egypt Several methods used for spectral enhancement of multispectral images are used on the Landsat 8 (Operational Land Imager; OLI) image in order to detect manganese layers in the study area. The imagery subjected to several data enhancement techniques before interpretations that included; principle component analysis, band ratio and band algebra. ENVI 5.1 and ArcGIS 10.2 packages were used for digital/mathematical processing steps and to apply the resulted models in the study area. The spectral signature curve behavior for four samples of manganese deposits had measured and examined carefully and its relationship with the surface reflectance (SR) values of Landsat 8 data, these relationship considered the factor for determination of the sensitive response bands for manganese interaction. Spectral signature is used to detecting the best formulas to mapping manganese layers. Interpretations done based on observations made after these manipulations, which gave characteristic differences for the manganese layers. The results confirmed by field verification and reveal a new method of integrated image interpretation in terms of spectral and spatial resolutions in identifying different rocks and minerals. The integration of those sensitive bands and the two mentioned methods are the main objectives of the present investigation. This should permit to create the manganese spatial distribution map for the study area. The measured spectral signature reflectance curve of the manganese resampled to meet the spectral characteristics of Landsat bands; both curves carefully examined to determine the most significant response bands for manganese, which were found to be bands 1, 4, 6 and 7. The examined spectral behavior led to seven significant band ratios. The results illustrate LANDSAT’s ability to provide information on defining manganese minerals, which are valuable for mineral exploration activities and support the role of PCA as a very effective and robust image processing technique for that purpose

Keywords: Abu Shaar el Qibli, Remote Sensing, PCA, Band Algebra, Manganese

INTEGRATING NEAR-SURFACE GEOPHYSICS, REMOTE SENSING, AND GIS DATA FOR ASSESSMENT OF WATER RESOURCES IN THE NORTHEASTERN PART OF THE EASTERN DESERT, EGYPT

Sharkawy, M. S.(1), Abd El Nabi, Si. H (2). Helaly, A. S (2), Araffa, S. A.S *(3) and Hassan, N. M (.4)

(1(  Department of Petroleum Geology, Faculty of Petroleum and Mining Sciences, Matrouh University, Egypt

(2) Department of Geophysics, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt

)3) National Research Institute of Astronomy and Geophysics, Helwan, Cairo, Egypt

(4 ) Department of Geology, Faculty of Science, Menoufia University, Egypt

and hydrogeological have been useful for delineating different water bearing areas. The Wadi Ghweiba and Wadi Badda basins represent the main basins in the studied area. The total area of Wadi Ghweiba is 1046 km2 of total runoff of about 7,187,315 m3/year with surface runoff 3,851,731 m3/year and net groundwater recharge of 3,335,584 m3/year. For Wadi Badda, the total area is 403 km2 and the total runoff of about 5,410,139 m3/year with surface runoff about 3,207,946 m3/year and net groundwater recharge of 2,202,193 m3/year. Forty-seven vertical electrical soundings (VES) were carried out using the Schlumberger configuration of AB/2 up to 1500 m. The Dar-Zarrouk parameters suggest that the northern, central and southern parts of the investigated area are fresh water-bearing.

Key words: Remote Sensing, GIS, D-Z parameters, and Groundwater

SUBSURFACE AND PETROLEUM GEOLOGY

RESERVOIR QUALITY DETERMINATION VIA WELL-LOG ANALYSIS OF ABU MADI FORMATION AT SOUTH MANSOURA AREA (ONSHORE NILE DELTA, EGYPT)

Elatrash, A.M. (1), Abdelwahhab, M. A. (2), Wanas, H. A. (3), El-Naggar, S. I. (4) and Elshayeb, H. M. (5)(1, 5) Department of Geology, Faculty of Science, Menoufia University

(2) Geology Department, Faculty of Science, Al-Azhar University, Nasr City, Cairo

(3) Derpatment of Petroleum Geology & Sedimentology, Faculty of Earth Sciences, King Abdulaziz University, Jeddah, Saudi Arabia

(4) Alamein Petroleum Company, Maadi, Cairo, Egypt

South Mansoura Area in Onshore Nile Delta represents a Messinian fluvio-estuarine depositional system, encompassing various sedimentary facies associations. The main hydrocarbon bearing facies are fluvial channel sandstones, filling the Eonile canyon. Well logs data, of 6 wells (namely; S.Aga-1, Aga-1, South Mansoura-6, N.Aga-1, South Mansoura-1, and Salaka-1) were used in this study, through computer processed interpretation. Petrophysical analysis, in terms of determining effective porosity, shale content, water saturation, and hydrocarbon saturation, of sandstones fluvial channesl of Abu Madi Formation, was the main focus of this research. This was performed in order to characterize Abu Madi sediments and determine its reservoir quality. The results showed that Abu Madi fluvial channel sandstones reveal good/efficient petrophysical properties adequate for bearing considerable amounts of hydrocarbons in South Mansoura Area of the Onshore Nile Delta.

Keywords: Petrophysical properties; Abu Madi Formation; South Mansoura Area; Onshore Nile Delta; Egypt

GEOLOGICAL PETROPHYSICAL ANALYSIS OF BAHARIYA FORMATION FOR THE DETERMINATION OF RESERVOIR QUALITY IN BED-2 FIELD, BADR EL DIN AREA, NORTH WESTERN DESERT, EGYPT

Ali, E.H. 1*, Abdelhafez, N. A. 1 and Abdelwahab, M. A. 2

1 Geology Department, Faculty of Science, Al-Azhar University, Nasr City, Cairo, 2 Oman Sea  PetroServices LLC. - Sultanate of Oman

Oil and gas are contained in pores of reservoir rocks such as sandstones and carbonates. In order to assess a possible hydrocarbon reservoir, the porosity and hydrocarbon saturation are needed to be known, which together define the amount of hydrocarbons per unit volume of rock.

Petrophysics, in its simplest form, is the calculation of porosity and fluid saturations as a function of depth in a well (Luthi, 2001). Wire-line logging evaluation is a vital part in the petroleum industry and is accepted as the most reliable and accessible geophysical-geological method for determining the petrophysical rock characteristics and locating hydrocarbons in well-bores (Schlumberger, 1974). The Bed-2 Field is located in Badr El Din Area, North Western Desert of Egypt. The main hydrocarbon bearing formation is the Late Cretaceous (Cenomanian) Bahariya Formation. The Well log data of eight wells (Bed 2-1, Bed 2-2, Bed 2-3, Bed 2-4, Bed 2-5, Bed 2-7, Bed 2-8, and Bed 2-10), were used through computer software program (IP,4.2) investigations in this study. the present study aims to Petrophysical analysis, in terms of determining the petrophysical properties (effective porosity, shale content, and fluid saturation) of Bahariya Formation, was the main objective of this study, to determine the quality of the reservoir in Bed-2 Field. We have found that Bahariya formation has good quality petrophysical properties capable of carrying large amounts of hydrocarbons in Bed-2 Field.

The experimental results and discussions show the petrophysical maps of Bahariya Formation, show matching between the petrophysical features. They show that the net pay and effective porosity tend to increase towards the northeastern part and northwestern part, while the shale content and water saturation tend to decrease towards this part.

Key words: Petrophysics; Bahariya Formation; Bed-2 Field; Reservoir Quality.

RESERVOIR CHARACTARIZATION OF ZONE) B) MEMBER OF UPPER BAHARIYA FORMATION, FARAS FIELD, NORTH WESTERN DESERT, EGYPT

Abd El Gawad, E. A., Abdelhafeez, Th.H., Fathy, M, and Saadoun, M

Geology Department, Faculty of Science, Al-Azhar University, Egypt

Faras Field is located within the Qattara Depression of the Abu Gharadig Basin within the North Western Desert of Egypt. (Fig.1) shows that the study area is bounded by latitudes 27º 10’ to 27º 50' N and longitudes 30º 00' to 30º 40' E, approximately 145 km south of the coastal town Marsa Matruh.

The present work is devoted to study the subsurface setting and reservoir characteristics of the study area to evaluate the hydrocarbon potentiality in the porous zones encountered in Bahariya Formation including the Upper Bahariya Formation and Lower Bahariya Formation. In this study we will focus on the Upper Bahariya Formation which subdivided into six members (Upper Bahariya, Zone A, Zone B, Zone C, Zone D and Zone E) mainly (Zone B), penetrated in five wells (Faras-3, Faras-26, Faras-34, Faras-41 and Faras-46) distributed in the area of study (Fig.2), according to the lithological identification and the petrophysical analysis. based on interpretation of well log analysis of five wells to highlight on the subsurface formation evaluation in the study area. Using software programs, such as Petrel 2017 software program (Shlumberger,(2017), and interactive Petrophysics version 3.6 (Shlumberger,2010). All inferred petrophysical parameters are represented vertically as litho-saturation cross plots and laterally as different iso-parametric maps such as effective porosity (Øeff), shale content (Vcl), net pay thickness, water saturation (Sw) and hydrocarbon saturation (Shr) maps. These maps revealed that the promising hydrocarbon bearing zones are characterized by their low clay contents, moderate effective porosity, thick net-pay, low water saturation which in turn, high hydrocarbon saturation.

The net reservoir distribution map shows that the reservoir thickness of Zone B Member of Upper Bahariya Formation, (the main reservoir in the study area), ranges between 10 -34 ft.  The effective porosity map shows that the reservoir porosity ranges between 24-32%, the shale content map shows that the shale content ranges between 3-22%, the water saturation map shows that the water saturation ranges between 20-60% and hydrocarbon saturation varies from 40- 80%.  

Keywords: Reservoir Characterization, Petrophysics, Subsurface, Faras, Upper Bahariya formation.

PETROPHYSICAL EVALUATION OF BAHARIYA RESERVOIR AT AMAN FIELD, WESTERN DESERT, EGYPT

brahim, M. (1) and. Abdel Fattah, N. (2)

(1) Egyptian Mineral Resources Authority.

(2) Geophysics Department, Faculty of Science, Cairo University.

This study is concerned with the evaluation of hydrocarbon potentials in the Shushan basin, northern western desert, Egypt, with a special attention for Bahariya formations. The area under study is affected by two normal faults forming a horst block. The downthrown side of F1 and F2 is directed towards the northeast and southwest trends respectively these two normal faults take same direction for main fault which affected Shushan Basin WNW-ESE. There are possibilities for hydrocarbon entrapment and particularly in the Bahariya formation. The expected immigration direction will be central part of study area between to fault which made horst and closure for hydrocarbon entrapment which makes a good closure for hydrocarbon entrapment.

Keywords: Well-Log Analysis, Net Pay Cutoff Calculation , Petrophysical Parameters

HYDROGEOLOGY

THE IMPACT OF GEOLOGICAL FACTORS ON THE GROUNDWATER AQUIFERS IN SAHL BARAKA AREA AND ITS VICINITIES, EL-FARAFRA OASIS, WESTERN DESERT, EGYPT

Aziz, A.(1), Sabet, H. S. (2) and Ghoubachi, S.Y. (3) 

(1, 3) Geology Department, Desert Research Center, 1 Mathaf El Matariya St.

(2) Geology Department, Faculty of Science, Al-Azhar University, Cairo, Egypt

The present work deals with the impact of the geological factors on the presence of the groundwater in the Sahl baraka area and its vicinities. The Geological and structure factors control the occurrences and flowing of the groundwater of the study area. Extracted groundwater in the study area is available from the Post Nubia (fracture limestone) and Nubia sandstone aquifers. Fracture limestone aquifer represented by Tarawan and Khoman chalk Formations. On the other hand the Nubia sandstone aquifer represented by Bahariya sandstone Formation. Nubia sandstone aquifer herein is subdivided into 3 aquifer units (A, B and C) according to their lithological characters and the majority wells tapping that aquifer exist under flowing artesian conditions. Results indicated that, the area is affected by sets of faults, fractures and joints that increase permeability and facilitate the upward leakage of the groundwater from Nubia sandstone aquifer to Post Nubia. The groundwater salinity of some wells tapping unit A reaches of 497 mg/l, while the groundwater salinity of the fracture limestone aquifer reaches of 529.5 mg/l. 

Keywords: Sahl Baraka area, Geology, Post Nubia aquifer and Nubia sandstone aquifer.

GROUNDWATER QUALITY AND ITS SUITABILITY FOR DRINKING AND IRRIGATION IN AKHMIM DISTRICT, SOHAG, EGYPT

Hagage, M.* (1), Madani, A. (2), Elbeih, S. F. (1), Faid, A. (1) and El Kammar. A. (2)

(1) The National Authority for Remote Sensing and Space Sciences (NARSS), Cairo,

(2) Geology Department, Faculty of Science, Cairo University, Egypt

In light of the limited surface water resources in Egypt, groundwater plays an increasing role for agricultural, industrial and domestic needs. Groundwater has a special significance in Akhmim District where it is the second source for freshwater used for the various purposes. However, it is currently threatened by pollution from different sources. Therefore, field studies and GIS techniques, were integrated to evaluate the groundwater quality at Akhmim District and evaluate its feasibility to be used safely for different purposes. Results showed the existence of several human activities that affect the quality of groundwater and its suitability for drinking and irrigation purposes. To avoid groundwater degradation, strict restrictions need to be applied on the use of untreated or treated wastewater for irrigation, sewage networks must be established in all residential areas, and factories must treat wastewater before discharging it.

Key words: Akhmim, Groundwater quality, suitability, Water Quality Index (WQI), GIS

DELINEATION OF GROUNDWATER ORIGIN IN NUBIAN SANDSTONE AQUIFER USING HYDROLOGIC ISOTOPES, BAHARIYA OASIS, EGYPT

Abd El-Latif, R. M.  1, Ahmed, K. A. 1, and Gomaa, M. A. 2

1 Hydrology Department, Desert Research Center, Cairo, Egypt

2 Hydrogeochemistry Department, Desert Research Center, Cairo, Egypt

Water stress is rapidly increasing in Egypt mainly due to expansion in agriculture and tourism. In this paper, we focus on groundwater of the Nubian Sandstone Aquifer System (NSAS) of the Bahariya Oasis to assess the capability of water stable isotope analysis (d D–d 18O) to delineate the understanding on monitoring the origin in time of a given water mass and isotopic tracers. Geochemical studies of groundwater of the Nubian Sandstone Aquifer (NSA) of the Bahariya Oasis reveal complex distributions and very much depletion in d 18O (-11 to -8.39) and d D (-85.96 to -73.36). The results suggest that all groundwater samples were distributed below the left part of the global meteoric water line (GMWL). The correlation  between δ2D and δ18O values indicate that the groundwater was recharged by precipitation (i.e. meteoric water origin). The stable hydrogen and oxygen isotope signatures of the Nubian aquifer System (NAS) of the Bahariya Oasis show discrete zonal distributions, indicating that the hydraulic connections between most water bearing bodies are similar. Accordingly, the Nubian sandstone aquifer in Bahariya Oasis is described as a multilayered artesian aquifer that behaves as one hydrogeologic system the stable isotope compositions showed that groundwaters in the Nubian Sandstone Aquifer seems to be a mixture of the recent meteoric water and paleo-groundwaters. A hypothetical mixing model is proposed to illustrate the contribution percentage of the two sources received by each sample depending on the topographic and the geological situation of each sample. The results of the mixing model suggest that groundwater from the Nubian Sandstone Aquifer has paleowater contribution percent ranging from 75 % to 100 % and rain contribution percent ranging from less than 1 % to 25 %. The relationship between deuterium excess and TDS for the groundwater samples shows that the deuterium excess values of groundwater of the Nubian Sandstone Aquifer (NSA) in the study area are lower than 10‰. This means that the increase in groundwater salinity was not caused by evaporation but mineral dissolution.

Keywords: Stable isotopes, Paleowater, Nubian Sandstone Aquifer (NSA), mixing model, Bahariya Oasis

ASSESSMENT OF WATER RESOURCES OF WADI NASAB FOR SUSTAINABLE DEVELOPMENT, GULF OF AQABA, SOUTH SINAI, EGYPT

Ahmed, K. A.1, Abd El-Latif, R. M. 1, El-Shamy, I. Z.2

1 Hydrology Department, Desert Research Center, Cairo, Egypt

2 Geology Department, Faculty of Science, Helwan University

 

The present study is an attempt to assessment the watershed characterization and potentiality of Wadi Nasab, southeast Sinai, Egypt using Remote Sensing (RS) and Geographic Information System (GIS) techniques. Thirty morphometric parameters (e.g. stream numbers, orders, lengths, frequency, as well as bifurcation ratio, drainage density and relief) were measured depending on SRTM data of Digital Elevation Model (DEM) with 30m resolution that enhanced by topographic maps (1: 50,000). The parameters were computed using ESRI’s ArcGIS 10.5, enriched by some Visual Basic (VB) code to compute stream numbers according to Strahler Theory Based on the values of the effective morphometric parameters, flash flood hazards were identified and evaluated.

The land use map was constructed from the geomorphological units of Wadi Nasab basin as well as the field observations. The drainage area of Wadi Nasab watershed is 370 km2. The morphometric analysis indicates that the watershed is of five stream orders with dendritic type of drainage pattern and homogeneous nature. The relief aspects such as Basin relief, relief ratio, Dissection index, ruggedness number and visual interpretation of the DEM indicate the overall steepness of the drainage basin, high overland flow and youthful or rejuvenated stage of geomorphic development with minimum denudation stage. On the other hand, Areal aspects as the drainage density, texture, circulatory and elongation ratios …etc. prove that the basin is less elongation shape, moderate stream frequency, moderate drainage texture which indicate moderate infiltration capacity and higher runoff with greater flow velocity results in potentiality of downstream flooding in the basin.

Moreover, the extracted thematic layers include slope, stream power (SPI) and topographic wetness (TWI) indices reveal availability of basin flooding. Accordingly, this basin most probably have moderate chance for groundwater recharge in the normal circumstances but with the proposed recommendation dams and dikes, good groundwater prospect occurred where the most rainfall infiltrate to recharge the aquifer via permeable soils and/or fractured and weathered rocks. Based on the Melton ratio which have a direct influence on flooding prone area, the predicting hydrogeomorphic hazards classification of Nasab basin is watershed prone to flooding. Hydrogeomorphic hazards must be identified in order to develop appropriate management strategies and design protective works. A flood control dam system has been reviewed, planned and recommended to construct in some sites in Nasab watershed to reduce damage from a flood surge. This system is very important to enhance recharging the existing aquifers. It is estimated that the proposed system for protection in W. Nasab can store as a maximum 10 Mm3 of runoff water with an efficiency of about 60 % of the maximum rainstorm.

The results of current study reveal that Nasab basin received a total 17 × 106 m3 of rainfall (February 2020) led to water harvesting potential of about 3.4 × 106 m3and total losses amounts about 13.6 × 106 m3.

Keywords: GIS; Morphometric analysis; Flash floods; Hydrological model; HEC-RAS; Wadi Nasab; Bedouin settlement; Sinai Peninsula; Egypt.

STUDY OF GROUNDWATER RESOURCES MANAGEMENT IN KHARGA OASIS, WESTERN DESERT, EGYPT

Abd El-Latif, R. M.

Hydrology Department, Desert Research Center, Cairo, Egypt

The increasing world population requires innovative approaches to water management and the use of existing technologies to explore and develop water resources effectively, in order to meet the developmental challenges facing human population. The study area identified the most promising areas for land reclamation projects and building new communities especially outside the Nile Valley and Delta part (NVD) of Egypt. The Kharga Oasis in the western desert of Egypt is an arid area that mainly depends on groundwater from the Nubian Sandstone Aquifer System (NSAS). In 1960s, Egyptian government started to use groundwater from the non-renewable Nubian Sandstone Aquifer System (NSAS) to expand agricultural sector. Due to over-use of NSAS groundwater, especially in Kharga Oasis, for industrial and agricultural applications during the last two decades, a significant drawdown of the water table has been observed. Because of this drawdown, an urgent and effective management strategy is required Management of groundwater resources can be enhanced by using numerical models to improve development strategies in the study area. However, the lack of basic data often limits the implementation of these models. A local mathematical model using Visual MODFLOW Flex 6.1 (Waterloo Hydrogeologic, 2019) was developed in the Kharga Oasis to analyze the behavior of the Nubian Sandstone Aquifer System (NSAS). Traditionally, model calibration in groundwater relied on manual trial-and-error adjustment of the model independent parameters (e.g., hydraulic conductivity, recharge, boundary conditions) until a good match between modeled and observed heads occurred. This will help in proposing different development scenarios and predicting the aquifer response to water abstraction. Accordingly, the local prediction simulation was used to evaluate two possible future development plans - Ordinary and Promising Scenarios - for the NSAS in the study area. The results of these scenarios run demonstrate that the groundwater potentiality in the Kharga Oasis is high. Fortunately, the results obtained from the Promising scenario indicate that cones of depression will be disappeared with long time from the southern and the northern sector of the Kharga Oasis and the maximum drawdown is raised from 113m (Ordinary) to 65.34 m (Promising) for the prediction year 2050 and raised from 121.31m (Ordinary) to 66.58 m (Promising) for the prediction year 2100.

Keywords: Groundwater modelling flow; Visual MODFLOW Flex software; Nubian Sandstone; Groundwater resources management; Kharga Oasis; Egypt.

HIGHLIGHTS ON THE SURFACE WATER RESOURCES IN WADI SAAL, AND THE POSSIBLE IMPACT ON GROUNDWATER, SOUTH SINAI, EGYPT

Abd El Latif, R. M.  1, Ahmed, K. A. 1, El-Shamy, I. Z. 2

1 Hydrology Department, Desert Research Center, Cairo, Egypt

2Geology Department, Faculty of Science, Helwan University

Since there is a direct relation between the geomorphological characteristics and the hydrological processes within the drainage basin, it’s important to develop a morphometric database as a primary step to understand the context of landform development. Its characteristics; and the pattern of its contribution to the hydrological system, However, using of Digital Elevation Model integrated with GIS environment can save time, effort, and provides accurate results. The aim of this paper is to analyze numerically the geomorphological characteristics of Saal drainage basin, south Sinai, Egypt, and its sub basins in details through deriving more than 22 morphometric parameters of all aspects and to evaluate and develop deep understanding of their hydrological implications. The drainage pattern in Saal basin is dendritic which indicates the presence of uniform resistance of rock to the drainage in the basin.

The visual examination and the areal indices estimated of shape of the Saal basin show that it is an elongated. Estimated geomorphic characteristics evidences (high Rb (Mean 4.4), moderate drainage density (1.78), moderate drainage frequency(2.33)  and low risk for flooding (zone A)), as well as the existence of thick alluvial deposits with good hydraulic properties covering the wadi floor of Wadi Saal furnish a suitable environment for the infiltration of running water and high replenishment groundwater potentiality for the underlying aquifers. This paper offers a morphometric database that can be used in sustainable management of water resources and future planning applications of rain water harvesting and flash flood risk assessment. The rainfall/runoff relationship and the peak runoff of the ungauged Saal hydrographic basin are calculated by using RM model (Rational Method model).

The application of the RM model is essentially depending upon the well-defined watershed parameters, which include; the rainfall intensity, the relief factors, the geological framework and the vegetation density. The Agroclimatology daily rainfall data were obtained from the NASA Langley Research Center (LaRC) POWER Project in the period (1982–2020) are used for the compilation of the Intensity-Duration Frequency (IDF) Curve. The degree of hazard is determined based on the morphometric parameters of the studied basin. The calculated value of peak runoff for the promising Saal basin is 2.7 x 106 m3 / hour. Flash Flood Protection Interventions of Wadi Saal flood can be achieved, using proposed Gabion structures dams in sites that of high Rb reaches in the selected watershed in order to reduce flow velocity and to promote recharging the alluvial aquifers.

Keywords GIS: Morphometric analysis; Flash floods; Hydrological model; Rational Method (RM) model; Wadi Saal; Bedouin settlement; Sinai Peninsula; Egypt.

GEOPHYSICS

TECTONIC TREND ANALYSIS AND THEIR EFFECT ON GROUNDWATER CHARACTERIZATION IN SOME SPECIFIC WADIES, IN SAINT CATHERINE AREA SOUTH EASTERN SINAI, EGYPT

El Nazer, A.M.  (1), Helaly, A. S.  (2), Hassan, S. M.  (3) and Abdel Gawad, A. M. (4)

(1) Egyptian Mineral Resource Authority (EMRA), Cairo, Egypt.

(2, 4) Department of Geophysics, Faculty of Science, Ain Shams University, Cairo, Egypt.

(3) National Authority for Remote Sensing and Space Sciences (NARSS), Cairo, Egypt

Magnetic and geoelectrical methods are applied in Saint Catherine area, southeastern Sinai, Egypt to determine the main structural trends, the tectonic origin of the area in addition to their effects on groundwater potentialities in some wadies in the considered area.

Magnetic data were represented by the total magnetic intensity map (TMI), which was processed through the reduction to the pole (RTP) technique. Then analyzing and processing RTP to produce regional and residual separation maps, second vertical derivative (SVD), source parameter imaging (SPI). After that analyzing RTP, regional and residual and (SVD) by using source edge detection (SED) and tilt angle derivative to produce trend analysis maps. The analysis and interpretation of the magnetic data concluded that at shallower depth levels, the predominant fault trend is NE-SW whereas at deep levels, the fault trend is also NE-SW. Therefore, the different fault trends at different depths as indicated by magnetic anomalies most probably indicate that the deformation of the area is related then thin skinned deformation and the faults affecting the Precambrian basement in the area play an important role in the study area. As show on SPI map the thickness of sedimentary cover is about 650m in the southwestern side and increases gradually to about 5 km towards the northern part and change occasionally in the narrower wadies.

Geo-electrical resistivity technique is used to detect the source of the groundwater and subsurface structure in some specific wadies. This technique was applied in the form of vertical electrical soundings (VES). Eighteen VES's are distributed through three profiles with AB/2 from 1 m to 500 m have been carried out. The results of geo-electrical survey delineate several features of the groundwater aquifers description as; the first geoelectrical layer consists of wadi deposit with thickness ranges between 1 m to 5 m it is considered dry, due to its higher resistivities. The thickness of second layer (Quaternary-Cambrian Sandstone) varies from 4 m to 42 m (1st aquifer layer). The third geoelectrical zone contains the weathering Precambrian rocks with thickness in range of 12 m to 273 m and the groundwater accumulated in the fractured of this zone (2nd aquifer layer). The fourth geoelectrical zone consists of massive basement where it shows high resistivity values. The study showed that the aquifers are related with structure elements.  

Keywords: Magnetic, Electrical Resistivity, Trend analysis, Tectonic origin, Saint Catherine, Egypt.

GEOPHYSICAL ASSESMENT OF MOGHRA AQUIFER TO THE WEST OF WADI EL-NATRUN, NORTH WESTERN PROVINCE, EGYPT

. Arafa, S. A. S (1), El-Shayeb, H. M. (2), Hassan, N. M. (2) and Hegab, M. G. M. (3)

1 National Research Institute of Astronomy and Geophysics (NRIAG)

2 Faculty of Science, Menoufia University

3 Research Institute for Groundwater (RIGW), National Water Research Center

Groundwater resources play an essential role in confrontation water resources scarcity in arid regions. The present work aims to identify Moghra aquifer to the west of Wadi El-Natrun. Depth to basement rocks, structural elements, depth to the aquifer, and its geometry will be detected using gravity and geoelectric resistivity tools. The potential field data (Bouguer gravity map) had been analyzed for various filtering processes. The regional-residual separation, Euler deconvolution, and radially averaged power spectrum are applied to constrain fault trends and depth to the basement. It was found that the trends of faults are NE – SW, SE – NW, E - W and N - S, while the main ones are NE–SW, and SE–NW. It was found that the depths of basement differ from less than 5000 m to more than 7000 m.

Vertical Electrical Soundings (VES) were measured at forty stations to define different subsurface geoelectrical units and the water-bearing zones. There are six geoelectrical units. The sixth unit is considered the one contains groundwater. The values of resistivity for this unit range between 8 and 50 Ohm.meter, and the expected depths of its uppermost surface differs from 106 m to 196 m from the surface. Relying on resistivity values, and the uppermost surface depth of the aquifer, priority map for the preferred locations for drilling groundwater wells was constructed.

Keywords: Groundwater aquifer, Gravity method, Geoelectric resistivity, Priority.

INFERENCES ON BASEMENT CONFIGURATION OF NORTHERN RAS QATTERA RIDGE, NORTHERN WESTERN DESERT, EGYPT; AS DEDUCED FROM POTENTIAL FIELD DATA INTERPRETATION

Azab,  A.  and Soliman, S. A.

Egyptian Petroleum Research Institute (EPRI)

Ahmad Alzomor Street, Alzohoor District, Nasr City, Cairo, Egypt

A combined gravity-magnetic anomalies interpretation to the north of Qattara Depression was done, supported by geologic background and wells, to better understanding the deep settings, which affect the shallower structural configurations. The work started by removing the regional trend of the deep crust from the original maps, to reduce the ambiguity inherent in the potential field data interpretation.  A set of second vertical derivative maps were prepared and used to overcome shortcoming for   subsurface situation of the original maps.

The optimum level of separation was calculated and subjected to further analyses with eye-focus on the ridges, sub-basins, faults, and igneous intrusions that possibly interrupt the basin-floor and the surrounding platforms. Various data-enhancement apperoeches were applied on the optimum SVD anomalies, to yield a better resolution of their source bodies and structures.

The outputs were discussed in terms of regional geology of the north Western Desert, to make the geological findings more reliable. The integrated approach reveals a good correspondence between the gravity and magnetic anomalies and their gradients. The deep and shallow constituents were overprinted by the Syrian arc folding, which apparently cut across the study area in the ENE-direction.

The easterly-oriented structural elements are dominant everywhere, that cut by the NW-SE(GOS) faults, forming several alternating anticlinal uplifts and synclinal troughs. The gravity-magnetic signatures are mainly sourced from a homogeneous basement of acidic composition and uneven topography. The floor of the Northern Basin is entirely subdivided into a number of sub-basins, separated from each other by local ridges, with regional northward dipping and lack of magmatic flows.

Keywords: Gulf of Suez, Western Desert, Applied Geophysics, Northern Basin, Qattara Depression.