South Eastern Desert Research Articles

Precambrian basement rocks of Wadi-Khuda-Shut area, South Eastern Desert of Egypt: Geology and remote sensing analysis

Wadi Khuda-Wadi Shut area in the South Eastern Desert (SED) of Egypt is mainly made up of gneisses, ophiolitic serpentinites and intermediate schistose metavolcanics. These metamorphic rock units are intruded by syn-late-tectonic diorite, granodiorite, ultramafic-mafic, and monzogranite intrusions. The gneisses comprise biotite hornblende gneiss, hornblende gneiss and migmatites. They are of granodiorite and diorite composition. The ophiolitic serpentinite with talc carbonate rocks were thrusted over the metavolcanics with NW-SE thrust contact. The late tectonic ultramafic-mafic rock units are represented in the study area by Dahanib pluton, which is consisted of layered peridotite-dunite associated with olivine gabrro, normal gabbro and gabbro-norite as well as rare hornblende gabbro. These varieties are related to the layered intrusions rather than Alaskan-types, and formed by magmatic differentiation. The granodiorite and monzogranite represent the youngest basement rock units in the study area. The principal components and band ratios of ASTER and Landsat-8 data were successfully used for the first time in lithological discrimination and geological mapping of the study area. This study concluded that, the interpreted data of ASTER and Landsat-8 combined with field study and petrographic investigation clearly discriminated the exposed rock units. Accordingly, a detailed geological map emphasizing the lithological units in Khuda-Shut area has been presented.

Geology and mapping of laterites, South Eastern Desert, Egypt: Based on field and ASTER data approach

The area between wadi Dungash–wadi Shait in the South Eastern Desert of Egypt comprises ophiolitic nappes structurally overthrust on island arc‐related metasedimentary–metavolcanic rocks, which are traversed by several granitoids, gabbroic and basaltic rocks. This paper focuses on uncovering laterite zones utilizing field geological, mineralogical and geochemical attributes of the investigation region. Laterites are distributed at the border between Neoproterozoic and Phanerozoic rocks. The laterite deposits are developed after the emplacement of Natash flows as a result of lateritization process in tropical regions, during the Late Cretaceous. The laterite sections comprise a sequence from the top to the base, oxide laterite, plasmic laterite, saprolith and bedrock. The laterite sections consist of hematite and goethite together with small quantity of gibbsite. Geochemically, the laterite profiles are marked by an increase in Fe content and decrease in Si from the top to the bottom. Fe2O3 is the most abundant with 30.09–54.67 wt.%, Al2O3 vary from 18.01 to 32.78 wt.%, and SiO2 vary from 15.05 to 19.43 wt.%. Advanced Spaceborne Thermal Emission and Reflection Radiometer images are utilised to characterize a primer laterite zone. The band ratio 4/5 is found to be efficient in defining the laterite soil in the studied area.

Tectonic Evolution of the Polydeformed Urf Al-Mahib Belt, South-Eastern Desert, Egypt

The Urf Al-Mahib area, located to the southern part of the Eastern Desert (SED) of Egypt, is covered mainly by juvenile Neoproterozoic crust and Nubian sandstones. Field investigation and structural analyses give evidence that the area of Urf Al-Mahib developed through four successive phases of deformation (D1, D2, D3 and D4). D1 was an attenuated phase represented by tight to isoclinal folds (F1), tightly appressed fold closures and sheared-out hinges, and axial plane foliation (S1), as well as mineral and stretching lineations (L1). Structural fabrics formed during the D2 phase embrace minor- and map-scale prominent F2 overturned folds with NW (to NNW)-dipping long upper limbs and short lower overturned limbs and axial planes striking NE (to ENE)‒SW (to WSW) and dipping to the NW at moderate angles. F2 folds are geometrically- and kinematically-related to thrust propagation, and often have SE (to SSE) vergence. Thrust faults, that striking NE (to ENE)‒SW (to WSW) and dipping NW to NNW, are also common in this stage. D3 structures contain pervasive vertical to inclined mesoscopic open to very open folds (F3), whose axes plunge NW (to NNW) and SE (to SSE) at moderate to steep angles. The latest D4 deformation phase is represented by abundant small- and large-scales WNW‒ESE trending dextral semi-ductile-semi-brittle-shear zones.

Integrating aeromagnetic data and Landsat-8 imagery for detection of post-accretionary shear zones controlling hydrothermal alterations: The Allaqi-Heiani Suture zone, South Eastern Desert, Egypt

The Arabian-Nubian Shield (ANS) underwent a regional carbonation event with CO2 fluxes derived from the mantle and circulated along post-accretionary shear zones, thus affecting the redistribution of gold mineralization. Formerly, the analyses of remotely-sensed data have suggested regions of gold mineralization linked to the post-accretionary structured framework, but the results were insufficient for detailed prospecting in the ANS. In this research, aeromagnetic data and Landsat-8 imagery were integrated for delineating new high potential zones of gold mineralization in the Allaqi-Heiani Suture (AHS) zone, the ANS, South Eastern Desert (SED) of Egypt. Aeromagnetic data were enhanced using the Center for exploration targeting (CET) grid enhancement technique to detect the main structures that control hydrothermal alterations in the study area. Principal Component Analysis (PCA) technique and ratios of spectral bands were applied to Landsat-8 data for mapping zones of hydrothermal alteration associated with gold mineralization. The traced structural elements from RTP, CET and Landsat-8 maps were statistically plotted and interpreted using rose diagrams. These diagrams indicated that the NW and NE trends are the most dominant in the RTP map and that the intersection zones obtained from the CET analysis are aligned along the NW-oriented trend. While the NNW, WNW and NE trends were the most dominant ones in Landsat maps. The integration of the results indicates several new high potential zones of gold and Cu/Ni mineralization types, which are mostly concentrated at the western part of the AHS zone. The hydrothermal alteration zones and associated gold mineralization are strongly linked to NW, NE, E-W and WNW trending lineaments. The approach used in this study can be applied to other parts of the ANS and other regions with similar geological conditions around the world.

Sources and behavior of trace elements in groundwater in the South Eastern Desert, Egypt.

Due to water scarcity, the groundwater will represent an essential source of water in many communities worldwide. This study was carried out to investigate the main hydrogeochemical characteristic of trace elements composition, their sources, and its vulnerability in groundwater to the human population. Fifteen groundwater samples were collected from boreholes and hand dug wells from the South Eastern Desert, Egypt, and analyzed for Al, As, B, Fe, Mn, Cd, Co, Cr, Cu, Hg, Ni, Pb, Rb, Sb, Sr, Th, U, V, and Zn using inductively coupled plasma mass spectrometry. Multivariate analyses were applied to identify the distribution and potential source of trace elements. The groundwater is tapped from the Miocene and the fractured basement rock aquifers. The mean concentrations of trace elements exceed the guideline values of all organizations, except in some wells for Zn, Cu, and Co. Cationic trace elements declined in the order of Mn > Fe > Zn > Al > V > Ni > Rb > Sr > U > Cu > Cr > Co > Cd > Pb > Th > Sb > Hg. Oxyanions As (mean 15.48 mg/L) and B (mean 1.24 mg/L) showed very high concentrations and higher than the average WHO concentrations in water suggesting potential adverse toxicity to all aquatic organisms. Five factor analyses indicated that different geochemical contributions are involved in the chemical characteristics of groundwater in the study area. Water-rock interaction and dissolution processes in bed rocks from different coastal Miocene deposits, meta-volcanics, basic-ultrabasic rocks, granitic and meta-sediments, seawater intrusion, residential wastes, and mining activities, in addition to the pH/Eh conditions, adsorption, and surface complexation during the chemical weathering are the main factors influence the trace elements distribution in groundwater. Results from this study for the six different groundwater aquifers are a unique insight into the sources and mobility of the observed trace elements in the groundwater and can be used in the assessment of contamination for drinking water wells. The association of trace elements from different aquifers might be useful in tracers studies of water-rock interaction. Due to the enrichment of trace elements in nearshore and crystalline groundwater aquifers in the study area and in similar areas worldwide, treatment technologies, and sustainable water management processes should be applied to prevent severe risks to the communities.

Preparation of Pure Nb2O5 from Gabal El-Faliq Pegmatite, South Eastern Desert, Egypt

The present work is concerned with selective dissolution of niobium from Gabal El Faliq concentrate sample by using fluoride-free process. The chemical analysis of concentrate sample revealed the presence of high amount of ZrO2, Nb2O5, Re2O3, and HfO2 assaying 33.6, 1.99, 4.8, and 1.2%w/w respectively. Several economic minerals including zircon, samarskite, fergusonite, and xenotime were recorded in the studied sample. About 98% of Nb content was selectively dissolved at the optimum conditions of 1:2 concentrate sample: KOH weight ratio, 2.5 h fusion time, and fusion temperature of 550 °C. Organic solvent extraction process using Aliquat 336S in xylene was effectively used for preparing pure Nb2O5 (98.95%).

Environmental Radioactivity of Radon and its Hazards in Hamash Gold Mine, Egypt

Radon concentrations have been measured using Sealed Can Technique with CR-39 detector for twenty collected samples from Hamash gold mine area, South Eastern Desert of Egypt. This area is one of the most important areas of gold-bearing granites in Arabian Nubian Shield and being used as a gold mine. Radon comes into the air from the natural decay of radium deposits in the rocks depending on the geographical and the geological features of the study region. The average values of radon concentrations, exhalation rates, annual effective doses, and working levels are found to be equal to 27.18 ± 0.13 kBqm-3, 3.27 ± 0.03 Bqm-2h-1, 686.27 ± 5.15 mSvy-1 and 2.94 ± 0.02 respectively. The results indicate that the radon concentrations of all samples are higher than the recommended world limit given by ICRP and IAEA. The present study can be used to assess any changes in the radioactive background and any harmful radiation effect on the human in this area.

Mineralogical and geochemical characterization of radioactive minerals and rare earth elements in granitic pegmatites at G. El Fereyid, South Eastern Desert, Egypt

The present work deals with the mineralogical and geochemical investigations of radioactive minerals and rare earth elements associated with granitic pegmatites at Gabal El Fereyid area exposed in the south Eastern Desert of Egypt. The study area is occupied by tonalite and monzogranites, the latter is intruded by pegmatites with a distinctive distribution of economically important mineralization. The studied pegmatitic bodies occur as veins that are ranging in size from few meters to 25 m long and their width usually less than 7 m; although small pockets are present. The latter display zoning structure (concentric layering) consisting of feldspar-rich zones enveloping pockets of mica (mainly muscovite) and all zoning internal quartz core. Field work using gamma spectroscopy measurements over these pegmatites shows that some bodies are radiometrically anomalous, especially the muscovite-rich zones. The mineralogy and geochemistry (trace and rare earth elements contents) of the radioactive zones in such pegmatites were achieved.Mineral characterization of the highly radioactive zones shows enrichment in thorite, uranothorite, ishikawaite, samarskite and fergusonite minerals. The spectrometric measurements of the studied pegmatites show that they possess the highest content of radioelements as well. They show enrichment in large ion lithophile elements (LILE; Pb, Rb, Sr) and high field strength elements (HFSE; Y, Zr, Th, U, Nb) and depletion in K, P and Ti. The studied granitic pegmatites indicate moderate to large negative Eu anomaly and show clear M-type tetrad effect of REE.The mineralogical and geochemical signature of investigated pegmatites represents a NYF-type (Niobium–Yttrium–Fluorine family), whereas the enrichment of rare element is an indication of high degrees of fractional crystallization of a suite of volatile-rich magmas. Uranium and thorium mineralization in the studied pegmatite are related to magmatic (syngenetic) origin with hydrothermal (epigenetic) input. The magmatic mineralization is evidenced by occurrence of thorite and zircon, whereas the hydrothermal activity is represented by alteration of feldspars and formation of pyrite and iron oxides associated with the radioactive minerals.The high levels of radioactivity and rare earth elements mineralization in the studied granitic pegmatite bodies make them a target to exploration and to enlarge the potentiality of the highly mineralized localities.

Thorium ions recovery using activated carbon modified with triphenyl phosphine oxide: kinetic and equilibrium studies

Activated carbon (AC) modified with triphenyl phosphine oxide (TPPO) was tested for thorium(IV) adsorption. Different factors affecting the adsorption process such as pH, contact time, modified AC dose, initial thorium concentration, triphenyl phosphine oxide (TPPO) concentration and temperature were investigated to optimize Th(IV) adsorption operating conditions. Kinetic and equilibrium studies of the adsorption process have been studied. The obtained most favorable conditions for Th(IV) adsorption were: pH 3.6, 40 min contact time, 0.5 g modified AC dose, 0.02 M TPPO in toluene and 400 mg/L of thorium concentration at room temperature. The maximum sorption capacity according to Langmuir isotherm reached 71.94 mg/g for modified AC. Adsorption kinetics obeys pseudo-second order kinetic model. Thorium(IV) was efficiently desorbed from the loaded composite using 0.5 M H2SO4 solution. The optimized factors have been carried out to recover thorium(IV) from Abu Rusheid leach liquor, south Eastern Desert, Egypt.

Remote sensing-based geological mapping and petrogenesis of Wadi Khuda Precambrian rocks, South Eastern Desert of Egypt with emphasis on leucogranite

The exposed Precambrian rocks along Wadi Khuda area, South Eastern Desert of Egypt, comprise gneisses, amphibolites and migmatites associations (infrastructural rocks) which are intruded by diorite, tonalite, syenogranite and leucogranite (LG). LG forms homogeneous boss like bodies, devoid to xenoliths, except along the outer margins. Chemically and mineralogically they are dissimilar to the surrounding gneisses. In the current study, band ratio and Decorrelation Stretch image processing algorithms were proposed and applied on Landsat-8, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Sentinel-2 remote sensing data to discriminate the widely exposed lithological units in the mapped area. Geochemically, I-type classification and volcanic arc environment were revealed. LG is peraluminous (ASI average of 1.09) with normative corundum up to 1.38 for LG. The LG displays limited major and trace element variations (SiO2 = 74.5–76.2%, AI203 = 13.4–14.4%), MgO = 0.03–0.19%, Na2O = 3.6–4.6%), and Rb = 55–85 ppm) probably due to textural and mineralogical homogeneity. The contents of REE in the leucogranite are low (∑REE = 21–37), but the REE patterns are [(La/Yb)n = 2.45–9.03], [(La/Sm)n = 1.09–2.6], with negative Eu anomaly, (Eu/Eu* = 0.19–0.78). The negative Eu anomaly and the low Sr content (16–92 ppm) may be attributed to the plagioclase feldspars fractionation. The leucogranites represent residual melt of syenogranite which forms Um Itly pluton at the southern flank of Wadi Khuda entrance.

Paleozoic glaciation in NE Africa: field and remote sensing-based evidence from the South Eastern Desert of Egypt

ABSTRACT Exhumed Paleozoic glacial deposits and landforms of the North Gondwana are reported here for the first time from the South Eastern Desert (SED) of Egypt. Using field observations and remote sensing datasets (Advanced Land Observing Satellite [ALOS], Phased Array L-band Synthetic Aperture Radar [PALSAR] radar, multispectral Landsat TM datasets, and digital elevation models [DEMs]), we mapped the distribution of Paleozoic glacial features (i.e. deposits and landforms) in the SED. Two main glaciogenic facies were identified in three locations in the SED: (1) massive, poorly sorted, matrix supported, boulder-rich diamictites in Wadi El-Naam and Korbiai, and (2) moderately-sorted, occasionally bedded outwash deposits in Betan area. Inspection of radar, DEMs, and Landsat Operational Land Imager (OLI) images revealed previously unrecognized ENE-WSW trending glacial megalineations (MLs) over the peneplained Neoproterozoic basement rocks in the central sections of the SED, whose trends align along their projected extension with those of glacial features (tunnel valleys and striation trends) reported from Saudi Arabia. The glaciogenic features in the SED are believed to be largely eroded during the uplift associated with the Red Sea opening, except for those preserved as basal units beneath the Nubia Sandstone Formation or as remnant isolated deposits within paleo-depressions within the basement complex. The apparent spatial correlation of the SED glacial features with well-defined Late Ordovician deposits in North Africa and in Saudi Arabia, and the reported thermochronometric analyses and fossil records are consistent with a Late Ordovician age for the SED glaciogenic features and support models that call on the continuation of the Late Ordovician (Hirnantian) ice sheet from the Sahara into Arabia through the SED of Egypt.

Multispectral and Radar Data for the Setting of Gold Mineralization in the South Eastern Desert, Egypt

Satellite-based multi-sensor data coupled with field and microscopic investigations are used to unravel the setting and controls of gold mineralization in the Wadi Beitan–Wadi Rahaba area in the South Eastern Desert of Egypt. The satellite-based multispectral and Synthetic Aperture Radar (SAR) data promoted a vibrant litho-tectonic understanding and abetted in assessing the regional structural control of the scattered gold occurrences in the study area. The herein detailed approach includes band rationing, principal component and independent component analyses, directional filtering, and automated and semi-automated lineament extraction techniques to Landsat 8- Operational Land Imager (OLI), Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Phased Array L-band Synthetic Aperture Radar (PALSAR), and Sentinel-1B data. Results of optical and SAR data processed as grayscale raster images of band ratios, Relative Absorption Band Depth (RBD), and (mafic–carbonate–hydrous) mineralogical indices are used to extract the representative pixels (regions of interest). The extracted pixels are then converted to vector shape files and are finally imported into the ArcMap environment. Similarly, manually and automatically extracted lineaments are merged with the band ratios and mineralogical indices vector layers. The data fusion approach used herein reveals no particular spatial association between gold occurrences and certain lithological units, but shows a preferential distribution of gold–quartz veins in zones of chlorite–epidote alteration overlapping with high-density intersections of lineaments. Structural features including en-echelon arrays of quartz veins and intense recrystallization and sub-grain development textures are consistent with vein formation and gold deposition syn-kinematic with the host shear zones. The mineralized, central-shear quartz veins, and the associated strong stretching lineation affirm vein formation amid stress build-up and stress relaxation of an enduring oblique convergence (assigned as Najd-related sinistral transpression; ~640–610 Ma). As the main outcome of this research, we present a priority map with zones defined as high potential targets for undiscovered gold resources.

Geology, mineralogy and mineral chemistry of the NYF-type pegmatites at the Gabal El Faliq area, South Eastern Desert, Egypt

The Gabal El Faliq area is located in the Eastern Desert of Egypt and belongs to the Wadi Hafafit–Wadi Ghadir fold belt. Lenses and dykes of rare metal-bearing pegmatites occur along major weak zones in the area (Wadi El Gemal strike-slip and its Riedel shears), by which they are structurally controlled. These pegmatites are mineralogically complex. Moreover, they are zoned, and the intermediate zones of the pegmatite varieties contain high amounts of zircon, fergusonite-(Y), columbite-(Fe), allanite-(Ce), xenotime-(Y), monazite-(Ce and Nd), thorite and gummite. These minerals carry Zr, rare earth element (REE), Nb, Ta, Th, U >Ta, F, and they are classified into rare-metal pegmatites, specifically, the niobium, yttrium and fluorine (NYF) enrichment family. The geochemistry aspects of these pegmatites indicate Zr up to 28,984 ppm, Hf up to 1171 ppm, REE up to 19,206 ppm, Nb up to 9962 ppm, Ta up to 152 ppm, U up to 565.5 ppm, Th up to 850 ppm and Ga up to 90 ppm. They were formed under an intracontinental tectonic setting from a basaltic magma similar to the oceanic island basalts (OIBs) contaminated with the crust. Consequently, this study could be used as a guide for the exploration of rare metals in similar regions of the world.

Gold endowment in the evolution of the Allaqi-Heiani suture, Egypt: A synthesis of geological, structural, and space-borne imagery data

Field and structural studies supported by multi-sensor satellite-based imagery data are attempted to decipher the setting and controls of gold-bearing quartz veins in the central part of the greater Wadi Allaqi district in the South Eastern Desert of Egypt. Here, we assess the evolution of a complex part of the Neoproterozoic Allaqi-Heiani suture (∼730–700 Ma) with ample structures demonstrating the final Gondwanan collision. Abundant extensive N-trending folds, sinistral shear zones and oblate fold patterns and strain fabrics exemplifying an oblique convergence and torsion related to a regional ∼E-W compressional regime.In the Wadi Seiga area, the first order upright and overturned folds and thrusts (D1 structures) are mostly obliterated by intense NW-ward transpression, N-ward folding and transcurrent shearing assigned to as D2 and D3 structures. The domal crescentic and mushroom superimposed fold patterns suggest that Type 2 and Type 3 fold interference patterns were synchronous at some time during D2 or D3. Shear zones with abundant signs of plastic deformation and associated with quartz veins, within the axial planes of NNW- and NNE-trending F3 folds may imply gold mineralization during the third deformation stage (D3). The latter was supplemented or terminated by an episode of northward tectonic escape and slip reactivation of the pre-existing NW-trending faults.Integrated with field measurements, satellite-based radar and radiometer data abetted untangling the superimposed structures. Gold occurrences in the area are confined to domains of superimposed foliations, foliation deflection/steepening, foliation refraction and substantial strain partitioning, or at oppositely interfered plunging folds. The scattered small scale occurrences of ≤10 s g/t Au-bearing gold-quartz veins in such high strain zones, together with the lack of spatial association with a particular intrusive phase weigh with the metamorphic model for gold-only endowment in the area. The peak metamorphic conditions (amphibolite facies) in the central Allaqi-Heiani suture were attained not earlier than 630 Ma, during the collision of the Arabian-Nubian Shield with the Nile Craton to the west (provoked at 670–610 Ma). Gold-only endowment was complementing to the latest stages of deformation and terrane cooling between 610 and 585 Ma. Listvenitization of tectonized ophiolites and widespread sericite alteration of the island arc metavolcaniclastic rocks could have been promoted by the late-orogenic felsic intrusions (∼603 Ma) that filled oblate dilation spaces developed by structural transport to the north. The late orogenic timing of mineralization is one of many features making the Allaqi-Heiani suture comparable to well-documented global examples of accretionary metallogenic belts.

Assessment of Radiological Hazard Indices in Abu Rusheid area, South Eastern Desert, Egypt, Using Gamma Ray Spectroscopy

The radiological hazard indices were determined using NaI(Tl) detector for twenty six collected rock samples from Abu Rusheid area, South Eastern Desert, Egypt. The Eastern Desert of Egypt is a source of granitic rocks used for uranium mining and also used as raw materials for building, for that reason cataclastic (mylonitic) rock samlpes were investigated to evaluate the radiation hazard indicators and compare the values of the world average values.The results show that, the distribution of radionuclides activity concentrations in the rock sample varieties affects the values of the absorbed dose rate in the studied rocks to be higher than the worldwide limit that are not safe for human. The average values of the total annual effective dose varied from 3.30 to 7.51 mSvy-1 and the lifetime cancer risk ranged from 2.31to 5.25. From the radiation protection point, the results were found above the worldwide average. These data record the radioactivity background levels in rock samples and could be used as reference information to assess any changes in the radioactivity background level due to different geological processes in the investigated area.

Sources of Radioelement’s and REEs in The Stream Sediments Bounded by Abu Rusheid Gneiss South Eastern Desert, Egypt

Sources of Radioelement’s and REEs in The Stream Sediments Bounded by Abu Rusheid Gneiss South Eastern Desert, Egypt

Utilization of full-polarimetric SAR data (RADARSAT-2), ASTER and Landsat 8 data in geological mapping of the west Gebal Elba area, Halayeb district, South Eastern Desert, Egypt

The present study explored the potentiality of integrating principal component analysis, minimum noise fraction, independent component analysis transformation and spectral ratioing of selected bands of Landsat 8 and Advanced Spaceborne Thermal Emission and Reflection Radiometer for geological mapping in west Gebel Elba area, Halayeb district, South Eastern desert, Egypt. Data fusion of optical and radar remote sensing using Color Normalization Transformation showed an effective approach to further identify lithological units and rock boundaries. The Freeman–Durden decomposition method was used to determine the dominant scattering mechanisms and to identify the current state of the surface cover. This approach provided solution for geological mapping of the study area, which is impeded by difficult accessibility and could be generic methodology for similar studies. It enabled to identify and map rock units and lithological formations at range of validly from 73% for wadi deposits to 90 for quartz diorite.

The annual effective dose of granite rock samples using alpha track detector

Radon concentration and annual effective dose for granite samples collected from Abu Rusheid area, South Eastern Desert, Egypt, were measured using passive technique with CR-39. It is important to ...

Preparation of Highly Pure Y2O3 from Rees Concentrate of Gabal El-Faliq Granitoid Rocks, South Eastern Desert, Egypt.

The present work aims to study the processing characteristics of the geologic ore material under consideration to prepare leach liquor suitable for the recovery of highly pure Y oxide concentrate. Ammonium sulfate roasting method was applied upon the study geologic ore material and selectively recovers 88.6% of total REEs. Several roasting parameters were investigated to optimize the selective dissolution of REEs. Since, from the foregoing results, it can be concluded that, the maximum dissolution efficiency, % of REEs from Gabal (G.) El-Faliq ore material by roasting with (NH4)2SO4 was conducted at Solid/Reagent ratio: 1/2, Roasting time: 2 hrs. and Roasting temperature: 600°C.From the latter, 91% of Y content from prepared RE(NO3)3 solution using 2M TBP, hasbeen recovered at pH of 1.5 by using 2M of TBP / Kerosene for 9 min. as contact timeand O/A ratio of 1/1. More than 98% of the loaded Y was regenerated using 3M HR2RSOR4Rat A/O ratio of 2/1 and contact time of 25 min. From the latter, highly pure Y2O3 Rwasprepared after oxalate precipitation.

The Geology, Geochemistry and Mineralogy of Beryl Mineralization in Zabara Area, South Eastern Desert, Egypt

The Geology, Geochemistry and Mineralogy of Beryl Mineralization in Zabara Area, South Eastern Desert, Egypt