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Sequence Stratigraphy and Rudist Facies Development of the Upper Barremian-Lower Cenomanian Platform, Northern Sinai, Egypt 被引量:3
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作者 Yasser SALAMA Michael GRAMMER +2 位作者 Shaban SABER Soheir EL-SHAZLY Gouda ABDEL-GAWAD 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第1期286-310,共25页
The Lower Cretaceous sections in northern Sinai are composed of the Risan Aneiza (upper Barremian-middle Albian) and the Halal (middle Albian-lower Cenomanian) formations. The facies reflect subtle paleobathymetry... The Lower Cretaceous sections in northern Sinai are composed of the Risan Aneiza (upper Barremian-middle Albian) and the Halal (middle Albian-lower Cenomanian) formations. The facies reflect subtle paleobathymetry from inner to outer ramp facies. The inner ramp facies are peritidal, protected to open marine lagoons, shoals and rudist biostrome facies. The inner ramp facies grade northward into outer ramp deposits. The upper Barremian-lower Cenomanian succession is subdivided into nine depositional sequences correlated with those recognized in the neighbouring Tethyan areas. These sequences are subdivided into 19 medium-scale sequences based on the facies evolution, the recorded hardgrounds and flooding surfaces, interpreted as the result of eustatic sea level changes and local tectonic activities of the early Syrian Arc rifting stage. Each sequence contains a lower retrogradational parasequence set that constituted the transgressive systems tracts and an upper progradational parasequence set that formed the highstand systems tracts. Nine rudist levels are recorded in the upper Barremian through lower Cenomanian succession at Gabal Raghawi. At Gabal Yelleg two rudist levels are found in the Albian. The rudist levels are associated with the highstand systems tract deposits because of the suitability of the trophic conditions in the rudist-dominated ramp. 展开更多
关键词 Cretaceous sequence stratigraphy RUDISTS sinai EGYPT
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数值研究Sinai台球能谱和粒子波函数分布特征
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作者 张正中 陈贺胜 《扬州大学学报(自然科学版)》 CAS CSCD 2008年第1期19-23,共5页
运用边界积分方法(boundary integral method,简称BIM)求解Sinai台球低能区的能谱及其相应的本征态波函数.将Sinai台球和1/4 Sinai台球对应能量的本征态波函数进行对照,由于两者对称性的显著差异,故其部分能级的本征态波函数表现出明显... 运用边界积分方法(boundary integral method,简称BIM)求解Sinai台球低能区的能谱及其相应的本征态波函数.将Sinai台球和1/4 Sinai台球对应能量的本征态波函数进行对照,由于两者对称性的显著差异,故其部分能级的本征态波函数表现出明显的不同. 展开更多
关键词 边界积分方法 能级 sinai台球 波函数
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Age structure and static life tables of the endangered Juniperus phoenicea L. in North Sinai Mountains, Egypt:implication for conservation 被引量:4
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作者 Emad A.FARAHAT 《Journal of Mountain Science》 SCIE CSCD 2020年第9期2170-2178,共9页
Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Midd... Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Middle East.The static life tables,survival curve and age structure of J.phoenicea populations from two mountains in North Sinai,Egypt(Gabal(G.)El-Halal and G.El-Maghara)were investigated.In each mountain,fifteen plots were selected,and field measurements such as stand density,tree height,and crown diameter were conducted.Moreover,44 trees were cored and crossdated according to standard dendrochronological procedures.The results showed that the tree ages ranged from 50 to 262 years at G.El-Halal and 96 to431 years at G.El-Maghara.Mature J.phoenicea individuals dominated the study area,with only a few individuals being younger than 100 years.Moreover,seedling recruitment was extremely limited.Since the studied J.phoenicea populations showed high mortality rates among both old and young individuals,there is an imminent need for establishing a conservation program to prevent its extinction in the future.Therefore,management and conservation efforts should be made to minimize human disturbance and protect the relic habitats of this endangered species at its southern distribution limits in Africa. 展开更多
关键词 Juniperus phoenicea Age distribution Life history MORTALITY Endangered plant sinai
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Petrologic and geochemical characterization and mineralization of the metavolcanic rocks of the Heib Formation,Kid Metamorphic Complex,Sinai,Egypt 被引量:2
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作者 Ibrahim H.Khalifa Mohammed Z.El-Bialy Doa'a M.Hassan 《Geoscience Frontiers》 SCIE CAS 2011年第3期385-402,共18页
Metavolcanic rocks hosting base metal sulphide mineralization, and belonging to the Kid Metamorphic Complex, are exposed in the Samra-Tarr area, Southern Sinai. The rocks consist of slightly metamorphosed varicolored ... Metavolcanic rocks hosting base metal sulphide mineralization, and belonging to the Kid Metamorphic Complex, are exposed in the Samra-Tarr area, Southern Sinai. The rocks consist of slightly metamorphosed varicolored porphyritic lavas of rhyolite-to-andesite composition, and their equivalent pyroclastics. Geochemically, these metavolcanics are classified as high-K calc-alkaline, metaluminous andesites, trachyandesites, dacites, and rhyolites. The geochemical characteristics of these metavolcanics strongly point to their derivation from continental crust in an active continental margin. The sulphide mineralization in these metavolcanics occurs in two major ore zones, and is represented by four distinct styles of mineralization. The mineralization occurs either as low-grade disseminations or as small massive pockets. The associated hydrothermal alterations include carbonatization, silicification, sericitization and argillic alterations. The base metal sulphide mineralization is epigenetic and was formed by hvdrothermal solutions associated with subduction-related volcanic activity. 展开更多
关键词 CALC-ALKALINE SULPHIDES MINERALIZATION Metavolcanic rocks sinai
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Geochemical Constraints of the Ediacaran Volcano-Sedimentary Succession of the Sa'al Metamorphic Complex at Wadi Zaghra, South Sinai, Egypt 被引量:1
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作者 SAMUEL D.Michael MOUSSA E.Hilmy +1 位作者 AZER K.Mokhles SADEK GHABRIAL Doris 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2019年第1期50-73,共24页
The volcano-sedimentary succession around Wadi Zaghra in Sinai, at the northernmost segment of the Arabian Nubian Shield, comprises volcanic rocks interbedded with rather immature sediments. The succession is dominate... The volcano-sedimentary succession around Wadi Zaghra in Sinai, at the northernmost segment of the Arabian Nubian Shield, comprises volcanic rocks interbedded with rather immature sediments. The succession is dominated by intermediate to silicic volcanics of medium-to high-K calc-alkaline affinity. It is divided into two units, the lower unit includes intermediate rocks and dacites interbedded with graywackes, semi-pelites and pelites and topped by polymict conglomerates. This unit is subjected to folding and regional metamorphism(up to garnet zone) and is intruded by quartz diorite-granodiorite inducing, locally, low-pressure contact thermal metamorphism. The unmetamorphosed upper unit encompasses acid volcanics intercalated with litharenite, sublitharenite and minor arenite. The rhyolites of this unit pertain to the highly fractionated granites and are characterized by an agpaitic index(NK/A) ranging from 0.87 to 0.96. They may reflect either extensive interaction of subduction-related magmas with the continental crust or a change in the tectonic regime. The present lithological and geochemical characteristics of the studied sediments together with available zircon ages indicate rather distal provenance of their detritus. This detritus comprises fluvial-alluvial sediments accumulated in the intermontane basins, which are half-grabens or tilted fault blocks. The tectonic setting of the depositional basins is active continental margin and continental island arcs. Geochemical patterns of the Zaghra volcano-sedimentary succession indicate their correlation with the Dokhan Volcanics-Hammamat Clastics sequence of the Eastern Desert of Egypt. Also, the Zaghra volcanics display geochemical similarities with those exposed in Sinai, at the Rutig, Ferani and Iqna Shar'a areas. The Zaghra succession is dated as Ediacaran but is not related either to the ensimatic island arc assemblage or to the rift-related assemblage formed during the early stages of the break-up of Rodinia as previously thought. 展开更多
关键词 geochemistry Neoproterozoic Dokhan VOLCANICS Arabian-Nubian Shield sinai EGYPT
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A Novel Approach in Hydrogeochemical Exploration for Uranium Mineralization:an Example from West Central Sinai,Egypt 被引量:1
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作者 Ahmed E.EL-RAYES Mohamed O.ARNOUS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第6期1895-1913,共19页
Groundwater in contact with ore deposits may acquire a chemical composition that could be used as a guide for exploration. Eight well-water samples are collected from a known uraniummineralized area near Abu Zenima, w... Groundwater in contact with ore deposits may acquire a chemical composition that could be used as a guide for exploration. Eight well-water samples are collected from a known uraniummineralized area near Abu Zenima, west central Sinai to examine the applicability of using the hydrogeochemical technique in the search for uranium mineralization in similar arid areas. The analytical chemical data of the ground water is compared with ground radiometric measurements. The obtained results indicate that groundwater affected by uranium mineralization has a specific relativity of major anions expressed essentially as SO_4〉Cl〉HCO_3 and to a lesser extent as Cl〉SO_4〉HCO_3, associated as a rule with low magnesium content. This association constitutes a signature of uranium mineralization on the composition of groundwater in west central Sinai and could be used as an important exploration guide in the search for uranium deposits in similar areas. Anomalies in Ni, Fe, Zn and Cr and other pathfinder elements in groundwater can furnish geochemical guides to uranium ores. The immobile trace element anomalies, including Zn, Ni and Fe are strongly distributed near the orebody; whereas the relatively mobile trace elements, including Co, U, V and Cr, constitute the dispersion haloes away from the orebody. A new hydrogeochemical discrimination diagram is constructed to be used as a quick and cost effective exploration tool in the search for uranium occurrences in environmentally similar arid areas. Based on the obtained results, a new site for uranium occurrence, west of W. Baba, is delineated and recommended for future detailed geological and geochemical surveying. 展开更多
关键词 Hydrogeochemical exploration Uranium ores geospatial mapping graphical explorationtool remote sensing sinai
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Mineralogical and Physical Characteristics of White Sandstone of Abu Rodeiyim Quarry(Sinai),and its Possible Industrial Utilization 被引量:1
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作者 Mostafa Gouda TEMRAZ 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期440-446,共7页
Mineralogical, geochemical, and textural analyses of the white sandstones (Abu Thora Fm.) of Carboniferous in the Abu Rodeiyim region show that they are fluviomarine, well-sorted, highpurity, and high-grade silica S... Mineralogical, geochemical, and textural analyses of the white sandstones (Abu Thora Fm.) of Carboniferous in the Abu Rodeiyim region show that they are fluviomarine, well-sorted, highpurity, and high-grade silica SiO2 (average 99.56%). The results indicate that by simple treatment, the white sandstones can reach a high degree of purity, suitable for different industrial purposes (e.g. manufacture of silicon photovoltaic, crystal, and TV screens, art, and domestic and optical glass). 展开更多
关键词 white sand industrial utilization Abu Thora sinai
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A Multidisciplinary Approach to Mapping Potential Urban Development Zones in Sinai Peninsula, Egypt Using Remote Sensing and GIS 被引量:2
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作者 Hala A. Effat Mohamed N. Hegazy 《Journal of Geographic Information System》 2013年第6期567-583,共17页
One of the main concerns of physical planning is the proper designation of suitable sites for feasible and sustainable land use. A main importance of such issue is that it withdraws attention to the necessity of adopt... One of the main concerns of physical planning is the proper designation of suitable sites for feasible and sustainable land use. A main importance of such issue is that it withdraws attention to the necessity of adopting a multidisciplinary approach to the zoning and site selection problem. Egypt has a top priority objective to develop Sinai Peninsula and to create new sustainable and attracting communities that should ensure a stable, economic and sustainable environment in vast desert zones. Due to the difficulty in solving a zoning problem in a desert, the use of remote sensing and Geographic Information System (GIS) was to explore the desert potentials in the region. Five sub-models were created for five themes using Spatial Multicriteria Analysis (SMCA) and used as inputs to the final suitability model. These themes are: land resources, land stability, accessibility, cost of construction and land protection. A GIS-based model was designed following a sustainable development approach. Economic, social and environmental factors were introduced in the model to identify and map land suitable zones for urban development using Analytical Hierarchy Process (AHP). The suitability index map for urban development was produced by weighted overlay of the five sub-models themes. The most suitable zones for urban development in Sinai Peninsula amounted to 5327 square kilometers representing 17% of total area, whereas high suitable zones reached 40% indicating a high suitability of Sinai Peninsula lands for residing new urban communities. 展开更多
关键词 Urban Development REMOTE Sensing GIS SITE Selection Themes ANALYTICAL HIERARCHY Process sinai EGYPT
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Vegetation diversity along the altitudinal and environmental gradients in the main wadi beds in the mountainous region of South Sinai,Egypt 被引量:1
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作者 Kamal H.SHALTOUT Yassin M.AL-SODANY +2 位作者 Ebrahem M.EID Selim Z.HENEIDY Mostafa A.TAHER 《Journal of Mountain Science》 SCIE CSCD 2020年第10期2447-2458,共12页
South Sinai includes Egypt’s highest mountains that resemble an ecological island surrounded by desert.The present study aims to analyse the vegetation physiognomy along the altitudinal and environmental gradients in... South Sinai includes Egypt’s highest mountains that resemble an ecological island surrounded by desert.The present study aims to analyse the vegetation physiognomy along the altitudinal and environmental gradients in the main wadi beds in South Sinai mountainous region.This includes determining the natural,native-weed and alien vegetation in representative stands in this region,analysing their vegetation in terms of species composition,abundance and life forms and determining the national and global distribution of the associated species.This investigation also aims to describe the prevailing plant communities and assess the role of environmental conditions that affect the vegetation in this region.Thus,thirty-two stands were chosen during March-June 2018 to reflect the prevailing altitude and environmental gradients.Total species was 316(229 genera and 61 families):186 species were perennials(58.9%),while 130 were annuals(41.1%).In addition,152 species were native weeds(48.1%of total species),31 were aliens(9.8%),along with 133 natural species(42.1%).Eight species were recorded as endemic to Egypt:Anarrhinum pubescens,Euphorbia sanctae-catharinae,Hypericum sinaicum,Origanum syriacum subsp.sinaicum,Phlomis aurea,Primula boveana,Rosa arabica and Solanum sinaicum.In addition,10 species were recorded as near-endemics to Egypt and other adjacent countries:Allium desertorum,Asclepias sinaica,Centaurea scoparia,Fagonia mollis var.hispida,Hyoscyamus boveanus,Iphiona mucronata,Micromeria sinaica,Pterocephalus sanctus,Salvia deserti and Stachys aegyptiaca.In the present study,33 species are threatened and categorized as follows:8 endangered,8 vulnerable and one indeterminate,while the rest were evaluated by the authors as rares.The rich plant diversity of this region is due to its extensive mountainous massif,which supports many microhabitats.The high elevations in this region hinder the dispersal process of propagules,a situation which often tends to increase endemic and near-endemic species.The current results were discussed and compared with some related previous studies. 展开更多
关键词 CONSERVATION Elevation gradient Multivariate analysis Plant diversity sinai Threatened species
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Analysis and Tectonic Implication of DEM-Derived Structural Lineaments, Sinai Peninsula, Egypt 被引量:1
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作者 Tarek Awad Seleem 《International Journal of Geosciences》 2013年第1期183-201,共19页
Sinai Peninsula has fascinating geologic setting and is displaying a diversity of structural lineaments that have greatly influenced the distribution of natural resources and hazards. Shaded relief images derived from... Sinai Peninsula has fascinating geologic setting and is displaying a diversity of structural lineaments that have greatly influenced the distribution of natural resources and hazards. Shaded relief images derived from SRTM-DEM mosaics were used for the identification, extraction, and mapping of these structural lineaments. Statistical parameters particularly, azimuth frequency, lineament intersection, lengths, and density distribution were analyzed using SPSS software. Two additional new statistical indices;Lineament Relative Abundance Index (LRAI) and Lineament Majority-Minority Index (LMMI) were applied. Moreover, the distribution of the different statistical parameters was illustrated as contour maps through GIS environment. Basically, two dominant clusters;NW-SE and NNE-SSW trends were detected. These trends are related to major fracture systems that are characterized by extensive mean lengths and high proportion values. Furthermore, the northern and central parts of Sinai Peninsula have lower density and intersection of structural lineaments that gradually increase towards the southern part. However, the northern part of Sinai displays wider areas of majority zones than the southern part. This could be attributed to the lower density of lineaments and little tendency for multiple lineament populations. The majority zones are usually associated with NE and NW-SE in the northern part of Sinai, whereas the majority zones are of less abundance in the central and southern parts of Sinai due to the multiple orientations of lineament populations which reduce the tendency for majority. Eventually, the results of the present work could be applicable in the different geologic and environmental aspects that are based on a good understanding of the genetic and spatial relationships of fracture systems. These aspects encompass geodynamics, exploration for mineralization and groundwater, in addition to the mitigation of natural hazards such as flush flooding and earthquakes. 展开更多
关键词 sinai PENINSULA STRUCTURAL LINEAMENTS Statistical ANALYSIS SRTM Image Processing GIS
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Palaeoenvironmental Reconstruction of the Early to Middle Miocene Sequence in West Central Sinai, Egypt, as Revealed from Fossil Diatoms
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作者 Abdelfattah A. ZALAT 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第1期354-366,共13页
A detailed analysis of the diatoms from the sedimentary sequence exposed in Abu Qada basin, west central Sinai, was used to determine the palaeoenvironmental changes during the Lower to Middle Miocene. A total of 85 d... A detailed analysis of the diatoms from the sedimentary sequence exposed in Abu Qada basin, west central Sinai, was used to determine the palaeoenvironmental changes during the Lower to Middle Miocene. A total of 85 diatom species and varieties belonging to 37 genera were identified from 154 samples collected throughout the stratigraphic succession. The lithological characters of the studied samples varied between sandstone, silty interbeds, sandy shales, shales, and terminated with anhydrite and limestones. These rock units are included in two lithostratigraphic formations (Rudies and Kareem), which are separated by a marked unconformity. The distribution and preservation of fossil diatoms in the sedimentary record are examined with the aim of outlining the temporal and spatial variation in the composition of the diatom assemblages, in order to estimate the changes in depositional environments during the Lower to Middle Miocene. The distributional pattern of the recorded diatom taxa distinguished four diatom eco-zones. The environment of each eco-zone is deduced and a proposed paleobathymetric change and depositional history of the Miocene sediments in the studied area are given. 展开更多
关键词 PALAEOENVIRONMENT Miocene sequence diatoms west central sinai EGYPT
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Use of Numerical Groundwater Modeling to Assess the Feasibility of Aquifer Storage and Recovery (ASR) in the Wadi Watir Delta, Sinai, Egypt
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作者 Osama M. Sallam 《Journal of Water Resource and Protection》 2019年第12期1462-1480,共19页
The lack of water resources in Egypt’s Sinai Peninsula is a major constraint for further socioeconomic development, and flash floods in this region can damage roads and infrastructure. The Wadi Watir basin is the mai... The lack of water resources in Egypt’s Sinai Peninsula is a major constraint for further socioeconomic development, and flash floods in this region can damage roads and infrastructure. The Wadi Watir basin is the main water source for the groundwater aquifer, which supplies fresh water to Nuweiba city, where demands for groundwater are increasing. The objective of this research was to assess the hydrogeological suitability of installing Aquifer Storage and Recovery (ASR) systems in the Wadi Watir delta by using numerical groundwater models. The developed models were used to evaluate the effects of hydrogeological and operational parameters on the recovery efficiency of ASR systems at five potential locations in the study area. As the estimation of recovery efficiency depends on the salinity of recovered water, the recovered water salinity limit was assumed as 150% of the injected water salinity, where 150% refers to the point at which recovery has ended because the concentration of recovered water reached 150% of that of injected water. The most important output from the model runs was that the recovery efficiency of these ASR systems ranged from 25% to 54% with a longitudinal dispersivity of 10 m, volume of injected water of 12,000 m3, and storage period of 180 days. The main conclusions are as follows. 1) Using coupled numerical groundwater flow and solute transport models is an effective tool for predicting the effects of mixing between injected water and ambient groundwater in ASR systems. 2) The groundwater aquifer in the study area is not suitable as strategic area for ASR systems because the thickness of the water storage layer is relatively small and the distance to the sea is very close;consequently, it is recommended that artificial recharge systems be developed with existing technology to replenish the groundwater aquifer in the Wadi Watir delta. 展开更多
关键词 AQUIFER Storage and RECOVERY (ASR) Groundwater Modeling WADI Watir sinai EGYPT RECOVERY Efficiency
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Genesis and Tectonic Implications of the Kabr El-Bonaya Ultramafic Rocks,Sinai Peninsula,Egypt:Constraints from Mineralogical and Geochemical Characteristics
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作者 Moustafa Mohammed MOGAHED 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第2期393-418,共26页
The Kabr El-Bonaya mafic–ultramafic intrusion is exposed along the southeastern border of the Sinai Peninsula and the northernmost segment of the Arabian-Nubian Shield(ANS).It occurs as an elliptical intrusive body t... The Kabr El-Bonaya mafic–ultramafic intrusion is exposed along the southeastern border of the Sinai Peninsula and the northernmost segment of the Arabian-Nubian Shield(ANS).It occurs as an elliptical intrusive body that is located along the major NE–SW trending fracture zones that prevail in the Kid metamorphic complex.The ultramafic rocks in the complex comprise ultramafic cumulates of peridotites(dunite,harzburgite and wehrlite)and pyroxenite.These rocks are generally unmetamorphosed and have intrusive contacts with the country rock.Mineral chemistry and whole-rock chemical compositions of these ultramafic rocks are mostly consistent with those of residual mantle peridotites from refractory suprasubduction tectonic settings.Based on the variations of the major elements,the studied ultramafic rocks are consistent with those of a supra-subduction zone mantle,as it seems to have melted at 1–2 GPa and 1300–1450℃.Linear variations of Al2O3,Ca O,V and Ni with Mg O,coupled with incompatible and rare-earth-element depletion and mineral compositions,suggest prior events of partial melting in both wehrlites and harzburgites.The LREE enrichment in the harzburgite,as well as the development of Cr-rich spinel,is consistent with a history of melt–peridotite interaction.The calculated(Sm/Yb)N variations for the studied peridotites indicate a general increase in the addition of fluids with an increasing degree of melting from the wehrlite(~13–15 wt%of fluid)in the source,after initial spinel peridotite melting to the harzburgite(~20–25 wt%of fluid)in the same source,which is contrary to normal abyssal peridotites.The estimated equilibration temperature ranges from 1214 to 1321℃for the studied wehrlites and from 1297 to 1374℃for harzburgites.The Mg-rich nature of the analysed olivines from the studied ultramafic rocks(Fo=81.41 to 91.77)reflect their primary composition and are similar to olivines in Alaskan-type ultramafic rocks.The Fo content of the analyzed olivines decrease slightly from the dunite to the harzburgite to the wehrlite and to pyroxenite,reflecting a fractional crystallization trend.The high Cr#and very low TiO_(2)contents(0.03–0.12 wt%)of the Cr-spinels from the studied peridotites are mostly consistent with modern highly refractory fore-arc peridotites,indicating that these peridotites developed in a supra-subduction zone environment. 展开更多
关键词 cumulate ultramafic rocks Alaskan-type rocks partial melting hydrous melting conditions supra-subduction zone Kabr El-Bonaya South sinai Arabian-Nubian Shield
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Constraints of Mantle and Crustal Sources Interaction during Orogenesis of Pre-and Post-collision Granitoids from the Northern Arabian-Nubian Shield:A Case Study from Wadi El-Akhder Granitoids,Southern Sinai,Egypt
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作者 Moustafa M.MOGAHED Khaled M.ABDELFADIL 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第5期1527-1550,共24页
The Egyptian older and younger granitic rocks emplaced during pre-and post-collision stages of Neoproterozoic Pan-African orogeny,respectively,are widely distributed in the southern Sinai Peninsula,constituting 70% of... The Egyptian older and younger granitic rocks emplaced during pre-and post-collision stages of Neoproterozoic Pan-African orogeny,respectively,are widely distributed in the southern Sinai Peninsula,constituting 70% of the basement outcrops.The Wadi El-Akhder,southwestern Sinai,is a mountainous terrain exposing two granitoid suites,namely the Wadi El-Akhder Older Granites(AOG)and the Homra Younger Granites(HYG).The AOG(granodiorites with subordinate tonalite compositions)have geochemical characteristics of medium-K calc-alkaline,metaluminous to mildly peraluminous granitoids formed in an island-arc environment,which are conformable with well-known Egyptian older granitoids rocks,whereas the HYG display calc-alkaline to slightly alkaline nature,peraluminous syeno-,monzogranites and alkali feldspar granites matching well those of the Egyptian younger granites.With respect to the AOG granitoids,the HYG granites contain lower Al_(2)O_(3),FeO^(*),MgO,MnO,CaO,TiO_(2),Sr,Ba,and V,but higher Na_(2)O,K_(2)O,Nb,Zr,Th,and Rb.The AOG are generally characterized by enrichment in LILE and LREE and depletion in HFSE relative to N-MORB values(e.g.,negative Nb and Ta anomalies).The geochemical features of the AOG follow assimilation-fractional crystallization(AFC)trends indicative of extensive crustal contamination of magma derived from a mantle source.The chemical characteristics of the AOG are remarkably similar to those of subduction-related granitoids from the ArabianNubian Shield(ANS).The compositional variations from monzogranites through syenogranites to alkali feldspar granite within HYG could not be explained by fractional crystallization solely.Correlating the whole-rock composition of the HYG to melts generated by experimental dehydration melting of meta-sedimentary and magmatic rocks reveals that they appear to be derived by extended melting of psammitic and pelitic metasediments,which is similar to the most of younger granitic suites in the ANS. 展开更多
关键词 older and younger granitoids mantle-crust interaction assimilation-fractional crystallization(AFC) southern sinai Arabian-Nubian Shield
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SINAI BOWEN RUELLE MEASURE AND THE STRUCTURE OF STRANGE ATTRACTORS IN THE LAUWERIER MAP
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作者 Wang Yi\ Cao Yongluo Dept. of Math., Suzhou Univ., Suzhou 215006. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期25-34,共10页
In this paper,the Lauwerier map F a,b (x,y)=(bx(1-2y)+y,ay(1-y)) is considered for a=4 . This map possesses a nontrivial topologically transitive attractor Λ which is the closure of the unstable set of... In this paper,the Lauwerier map F a,b (x,y)=(bx(1-2y)+y,ay(1-y)) is considered for a=4 . This map possesses a nontrivial topologically transitive attractor Λ which is the closure of the unstable set of some hyperbolic fixed point. Periodic points are dense in Λ and all of them are hyperbolic with eigenvalues uniformly bounded away from 1 in norm. Moreover,any two periodic points are heteroclinically related (transversal intersection of their stable and unstable sets). The Sinai Bowen Ruelle measure supported on the attractor is constructed and its properties are studied. 展开更多
关键词 Strange attractors sinai Bowen Ruelle measure transversal homoclinic point.
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The Great Gulf of Aqaba 1995 Earthquake Design Response Spectra over Sinai Peninsula and Some Jordanian Soils
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作者 Mohamed A. Gamal Ahmed Abdelwahed 《International Journal of Geosciences》 2019年第4期463-480,共18页
The Gulf of Aqaba area is considered one of the most terrific touristic areas in the Middle East. The aim of the present work is to determine the amount of seismic hazards that the constructions may suffer due to seis... The Gulf of Aqaba area is considered one of the most terrific touristic areas in the Middle East. The aim of the present work is to determine the amount of seismic hazards that the constructions may suffer due to seismic activities. This is done by determining the design response spectrum for this area from available earthquake response spectra, then taking into consideration the soil response for some Egyptian and Jordanian soils. The main shock of the November 22, 1995, the Gulf of Aqaba and its aftershocks were mainly used in producing the design response spectrum. This earthquake was considered as the biggest earthquake that hit this area since 160 years. Its magnitude was determined as Mw = 7.2. Thousands of aftershocks with intermediate magnitude followed the main shock, such as the aftershock that occurred on November 23, 1995 with a local magnitude of ML = 5.4. The best estimate of the focus location was determined in the area between Dahab and Nuweiba cities. This great earthquake was felt in Lebanon, Syria and Israel in the North and Egypt, Saudi Arabia and Sudan in the South. The touristic areas surrounding the Gulf of Aqaba were mostly affected. Different accelerograms for this great earthquake were collected and soil responses spectra for Sinai Peninsula and some Jordanian soils were calculated. The design response spectrum shows an average spectral acceleration of about 250 cm/sec2 for frequency range between 1 - 10 HZ. Soil Amplifications were then calculated using Microtremors site response technique and maximum spectral accelerations filtered by the soil were in range between 120 - 450 cm/sec2 for the study area. The analysis presented here is intended to be used in the future to allow reducing the seismic risk, help in proper structural design and detailing of buildings and structures to account for beam-column connections and shear reinforcement. 展开更多
关键词 sinai PENINSULA RESPONSE Spectrum Soil RESPONSE Spectral Acceleration Seismic HAZARD GULF of Aqaba PGA
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Sedimentology, Structure and Depositional Environments of the Subsurface Cretaceous, North Sinai, Egypt Using Well Logs
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作者 Fouad Shaaban Amani Bourselli +1 位作者 Adam El-Shahat Mostafa El-Belqasi 《International Journal of Geosciences》 2020年第3期37-57,共21页
A complete set of well logs was used to study the sedimentology, structural and depositional environments of the subsurface Cretaceous rocks of northern Sinai, as a promising hydrocarbon province in Egypt. The sedimen... A complete set of well logs was used to study the sedimentology, structural and depositional environments of the subsurface Cretaceous rocks of northern Sinai, as a promising hydrocarbon province in Egypt. The sedimentological interpretations of well logs show sedimentary sequence of the Early Cretaceous, represented by the Neocomian, Aptian and Albian, which is composed mainly of shales and marls with minor carbonate and sandstone intercalations. Based on the Th/K ratios, the argillaceous sediments are composed of illite, montmorillonite and micas with little amounts of glauconite and chlorite. The environmental interpretations revealed sedimentological environments vary from estuarine to lagoonal and backreef of the Barremian-Aptian rocks, and from continental to estuarine in the Aptian-Albian. By contrast, the Late Cretaceous rocks, represented by the Cenomanian, Turonian, Santonian and Maastrichtian, are mainly composed of carbonates with few shale and marl intercalations. This sequence was accumulated under lagoonal to neritic and bathyal environments. The structural interpretations of well logs show that the Cretaceous section attains a wide range of dip magnitudes and dispersed azimuths all over the study area, which is probably attributed to tectonic and sedimentological processes. The inherited structural complexities indicate possible rejuvenations along old fault planes and rotation of the faulted blocks. 展开更多
关键词 NORTH sinai CRETACEOUS SEDIMENTOLOGY STRUCTURE Environment Well LOGS
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Flash Flood Risk Assessment Using Morphological Parameters in Sinai Peninsula
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作者 Ashraf M. Elmoustafa Mona M. Mohamed 《Open Journal of Modern Hydrology》 2013年第3期122-129,共8页
Flash floods are considered to be one of the worst weather-related natural disasters. They are sudden and highly unpredictable following brief spells of heavy rain. Egypt is subjected to flash floods, especially the e... Flash floods are considered to be one of the worst weather-related natural disasters. They are sudden and highly unpredictable following brief spells of heavy rain. Egypt is subjected to flash floods, especially the eastern desert and Sinai Peninsula where floods from the mountains of Red Sea and Sinai are causing heavy damage to man-made features. This manuscript presents the methodology adopted to generate a weighted risk map for main watersheds located in Sinai according to main morphological parameters. Using digital elevation model (DEM) implemented into a Geographic Information System (GIS) the Sinai watersheds were delineated and morphological parameters calculated. The parameters where then used in a multi criteria analysis process to calculate a morphological risk factor. The resulted risk maps of this study can help initiating appropriate measures to mitigate the probable hazards in the area with prioritization. 展开更多
关键词 Flash Floods MORPHOLOGY MCA sinai PENINSULA ARID Region
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Calcareous Nannofossil Biostratigraphy and Stage Boundaries of the Santonian-Eocene Successions in Wadi El Mizeira Northeastern Sinai, Egypt
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作者 Hamza Khalil Esam Zahran 《International Journal of Geosciences》 2014年第4期432-449,共18页
The stratigraphic successions exposed in Wadi El Mizeira have been dated through the analysis of the calcareous nannofossil assemblages. The results of this study indicate that the successions comprise the Santonian-L... The stratigraphic successions exposed in Wadi El Mizeira have been dated through the analysis of the calcareous nannofossil assemblages. The results of this study indicate that the successions comprise the Santonian-Late Maastrichtian (Sudr Formation), the Paleocene (Esna Formation) and the Early Eocene (Thebes Formation). The following biozones were recognized: Late Santonian, CC16 Zone;Late Santonian/Early Campanian, CC17 Zone;Early Campanian, Aspidolithus parcus Zone (CC18) Zone;Late Maastrichtian, CC25c Zone;Early Paleocene (Late Danian), NP3 Zone and NP4 Zone;Late Paleocene (Thanethian-Selandian), NP5 Zone;Early Eocene, NP9b Zone, NP10a Zone, NP11 Zone, NP12 Zone and NP14 Zone. Several stratigraphic hiatus were recorded in the studied interval including the absence of Cretaceous nannofossil Zones CC19 to CC25b and CC26 as well as the early Paleocene Zones NP1 and NP2 and probably the basal part of Zone NP3, in addition to the absence of the Zones NP6 and NP7/8. These hiatus may be attributed to environmental conditions, structural activity and/or post depositional processes. This work represents the first attempt to evaluate the nannofossil taxa of the Wadi El Mizeira, Northeastern Sinai. 展开更多
关键词 Calcareous Nannofossil BIOSTRATIGRAPHY SANTONIAN EOCENE sinai EGYPT
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A Comparison Study of Soil Samples from Sinai Province in Egypt by Using X-Ray Diffraction and Gamma-Ray Analysis
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作者 Shadiah S. Baz 《World Journal of Nuclear Science and Technology》 2015年第2期120-128,共9页
Ten soil samples from Jabal Al Qur, Wadi Baba, and Wadi Sieh in Sinai, Egypt, were analyzed by XRD spectroscopy. The XRD spectroscopy results indicate that the major, minor and trace constituents varied from one sampl... Ten soil samples from Jabal Al Qur, Wadi Baba, and Wadi Sieh in Sinai, Egypt, were analyzed by XRD spectroscopy. The XRD spectroscopy results indicate that the major, minor and trace constituents varied from one sample to another. Samples were also analyzed by HPGe gamma spectrometer to determine the activity concentration of U-238, Th-232 series and K-40. The concentrations for 238U ranged from 57.03 to 4220.41 Bq/kg with an average 1110.75 Bq/kg, for 232Th, ranged from 13.55 to130.46 Bq/kg with an average 71.85 Bq/Kg. The concentrations for 40K were in the range from 12.18 to 948.93 Bq/kg with an average value 457.09 Bq/kg. The average activity concentration values of 226Ra, 232Th, and 40K, in all the collected samples were higher than the world average. The radium equivalent (Req), absorbed dose rate (DR), the effective dose rate (Deff), and hazard indices resulted due to the natural radionuclides in soil are also calculated. The Results show that the study area is not safe for human and environments. 展开更多
关键词 sinai Soil X-Ray Diffraction Natural RADIOACTIVITY Concentration Chemical CONSTITUENT Diffract Meter
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