| Abstract: |
The present study deals with an area located in the Central Eastern Desert. It lies between latitudes 25?12? to 25? 32? N and longitudes 34? 10? to 34? 50? E. Satellite data including landsat thematic mapper (TM) has been processed and Satellite images haField verification, measurements, and laboratory analyses have been used to increase the accuracy of these mapsGeomorphologically, the area could be classified into different geomorphologic units including:Denudation landforms as mountains (Umm Naqqat and Abu Daib), denudation hills, mesas and cuestas.Deposition landforms, which include alluvial fans, terraces, karst, badlands, sandsheets, and wadi deposits.Coastal plain, which include shores, beaches, lagoons, islands and coral reefs.The water resources in the investigated area could be classified into surface, ground and desalinated waters. To study the surface water, the drainage network map of the study area has been prepared that the investigated area includes nine drainage basinsVisual interpretations of the landsat thematic mapper (TM) images and field verification revealed the occurrence of different basement and sedimentary rock units. The igneous rocks could be classified into ophiolites and related rocks, metasediments, metaTwo stratigraphic successions were measured and studied at two localities namely, Wadi Mubarak and Wadi Shuni. The following formations arranged from older to younger Gebel El Rusas, Abu Dabbab, Samh, Gabir, Shagra, Organic reefs, Raised beaches and RecenGebel El Rusas Formation rests unconformably on the basement rocks. It consists of two members, the lower member only present at Wadi Mubarak. It measures 0.5 to 1.0 m thick at Wadi Mubarak. The upper member is cropping out all the area. Its thickness in Abu Dabbab Formation overlies conformably on Gebel El Rusas Formation. It consists mainly of gypsum. Its thickness in the studied successions measures 20.5 m thick at Wadi Mubarak and 22.0 m thick at Wadi Shuni. Petrographically, the Abu Dabbab Formation Samh Formation overlies unconformably the Abu Dabbab Formation. It consists mainly of thick bed of sandstone followed by calcareous claystone and shale intercalation with thin bands of gypsum. Its thickness in the studied successions measures 6.0 m thick Gabir Formation overlies conformably over Samh Formation. It consists mainly of sandstone successions. Its thickness in the studied successions measures 2.2 m thick at Wadi Mubarak and 2.0 m thick at Wadi Shuni. The petrographical study of the upper part Shagra Formation conformably overlies the Gabir Formation. It consists mainly of limestone. It measures 8.0 m thick at Wadi Mubarak and 10.0 m thick at Wadi Shuni. The Shagra Formation is described as biopelsparite. Most peloids are of fecal origin and haPleistocene organic reefs cropping out at the two localities. It consists of limestone. Its thickness in the studied successions measures 6.0 m thick at Wadi Mubarak and 5.0 m thick at Wadi Shuni. The Pleistocene organic reefs are described, as biolithiteThe Recent reefs cropping out at the two localities. It consists of limestone. Its thickness in the studied successions measures 7.0 m thick at Wadi Mubarak and 5.0 m thick at Wadi Shuni. The petrographical study indicated that limestone is composed of alThe structural elements affecting the area have been identified. These elements include bedding structures (parallel and cross lamination, ripple marks, gradded bedding and mud cracks), fractures, joints, folds and faults of different trends mainly NNW anMechanical analysis of studied sands reveals that 12 samples are unimodal (i.e., well sorted) and 8 samples are bimodal (i.e., moderate sorted). The cumulative curves of the studied sandstone seem to represent river sands, since the central parts of the cMean size for the studied sand samples show that the mean size values of Gebel El Rusas, Raised beaches and Terraces are coarse sand, Samh and Gabir formations are medium sand, Wadi deposits and beach sands are fine sand. The inclusive graphic standard deA plot of standard deviation against mean size of the most samples shows no general trend of variation, while some samples shows V- shaped (i.e., small rang grain size).The scatter plot diagram of the main size against skewness shows 6 samples of negative sign (i.e., coarse skewed) and 14 samples of positive sign (i.e., fine skewed).Mineralogical study of sandstone samples reveals that the light fractions are formed mainly of quartz and feldspars represented by few grains of orthoclase and plagioclase. The heavy fractions of the studied samples are composed of opaques (> 70 %) and noIn order to estimate the maturity of the concerned sediments, some heavy mineral ratios were calculated. These are zircon/tourmaline, zircon / rutile and zircon / rutile + tourmaline. In addition, the degrees of weathering were estimated. These are Wr1 (pThe land resources in the area have been studied including mineral deposits, ornamental stones, and building materials. The area is very rich in mineral deposits, which include; those associated with ultramafic and layered mafic rocks (as chromate and cop
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